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Infertile/Unhatched Bluebird Eggs (Part 1)Subj: infertile eggs Date: 4/29/99 7:24:58 AM Central Daylight Time From: kridler"at"1Starnet.com (Keith & Sandy Kridler) Just re-read in the Ellis Bird Farm newsletter edited by Myrna Pearman in the spring 1999 this article about infertile eggs. I will only send the last part from Dr. R.H. Dykes, Prince George, C.( "These infertile eggs act as a medium for incubation of various types of viruses and bacteria. E-coli, strep and staph come to mind. If the nestlings break an infected egg and the yolk spills into the nest, the resulting infection could be lethal to the nestlings. I suggest that all sterile eggs be carefully removed from a nest.") I don't know if this is the "scientific" proof you wanted or just common sense.KK Subj: Unhatched Eggs Date: 6/28/99 10:03:29 PM Central Daylight Time From: statton"at"toolcity.net (statton) Chris Statton, Cochranton, NW PA A few days ago there was an inquiry concerning whether unhatched eggs should be removed from a nest. If I may, there was an interesting reference to this subject in the current issue of "Bluebird" (the NABS newsletter). This reference was a quotation from an item that was, in turn, originally published in the Ellis Bird Farm newsletter. (I hope I've given the appropriate due credit.) In any event, a Dr. R.H. Dykes of Prince George, BC – "a physician, farmer, and bird enthusiast" – is quoted as advising that unhatched eggs should be removed because they could be rife with viruses and bacteria (E-coli, strep, and staph, etc). If the eggs are infected and were to accidentally be broken by the hatchlings or adults the hatchlings could be fatally infected. Not indicated in the article, but I cannot help but wonder that it might also be possible for humans to also contract the diseases caused by these bacteria and viruses in the event of contact with them through aaccidentally broken eggs. Unrelated to those sources, I have also been told or read somewhere that the unhatched eggs can draw warmth away from hatchlings. Of course, I would recommend an appropriate waiting period to be certain there isn't just a delay in hatching of a viable egg, then that unhatched eggs be carefully removed from the nest if the adult birds do not remove or bury them in the nest. From: MSBOC"at"aol.com [mailto:MSBOC"at"aol.com] Sent: Wednesday, June 30, 1999 6:41 PM Subject: Checking for unhatched egg........ ... My next question is: I have four nestlings as far as I can ... Nancy Subj: RE: Checking for unhatched egg........ From: "eveningprimrose" primrose"at"lcii.net Greetings all, This was definitely the 2nd brood for this couple, as I saw 3 siblings follow Dad to the area Monday. So far, they have just *mocked* their mother by pecking around on the ground. They are already about as big as the parents, but I am not sure about their sex (have bad PIC's). I am guessing they are females, but since this is my 1st EABL experience, who knows? I knew that some other people around me had already had a successful set of 5? fledglings. I had the house installed by a friend in mid-March, but I kept getting HOSP nests. I removed the nest and eggs twice. They were very messy nests, which included cellophane wrappers. I didn't use the exact directions, but did string up some monofilament line around the house. I can't say that this is why I finally got my BB nest, but I did! I am sure that there are plenty of insects around the area
for food. It has been a rainy season...so the ground is ripe
for "pickin". However, I am trying to get them to
feed at a feeder, when they fledge. Thus, I bought an *expensive*
container of 30? mealworms yesterday (used as bait around these
parts). I put out 6 of them in an old Frisbee. Mom has totally
scoped out the situation and is ignoring them. Five out of six
worms appear to have died. Was I supposed to feed them, also?! Date: Sun, 11 May 2003 12:47:56 -0700 (PDT) Hi...A question about multiple infertile eggs. This year 1 of my boxes had 5 Chickadee eggs laid. Only 2 hatched & eventually fledged fine. After the 2 hatchlings were about a week old & thinking that the 3 eggs weren't hatching, I removed them from the nest. Question..has anybody ever had more than 1 ...say 2 or 3 or more infertile eggs in any box? Thanks for your answers.... Horace in N.C. Date: Mon, 12 May 2003 03:21:44 -0700 (PDT) Nancy Johnson, Gainesville, FL Hi Horace & list, One of my Eastern Bluebird nestboxes had 4 eggs and only 2 hatched in the first nesting this year. The 2 EABL eggs which didn't hatch had been moved to an outer corner of the box outside the nest and almost fell out when the box side was opened for inspection. I pulled the nest out far enough to get a good look at the 2 nestlings and found a Brown-headed Cowbird egg. I don't think the Cowbird damaged the unhatched eggs. The rejected eggs and the Cowbird egg were removed. One EABL egg broke open when picked up and it seemed completely undeveloped (infertile). The parents aggressively defended the nest, dive-bombed me
at every nest check, and the 2 babies fledged on 5/6/03. The
used nest was removed and I also had a nest box of Carolina Chickadees with 5 eggs where
only 4 hatched and fledged this past month. The infertile egg
moved around the nest as the nestlings moved around and was
still there after they fledged. Subject: Infertile Clutch We (my wife and I) have an Eastern Bluebird nest that was incubated since 4/14/03(a clutch of 5 eggs). We have now seen the female spending more time outside the box and the male has been entering the box with grass. We have also seen the female coming to the opening with grass while the male is inside the box. The eggs were still visible this morning and I could not tell that a new nest was being built over it. We are wondering if they are building a nest over the old. Should we empty the nesting box or just allow them to do their thing? Thanks From: hubertrap"at"webtv.net (Joe Huber) Hi Folks, Yes the Bluebirds sometimes build over old nests. If your nest box opens in a way you can remove the lower part,or old nest you could wait till they finish the new nest. Don't know if there is a best time to do this, but this nest will end up very close to the entrance hole where a larger bird may reach in and cause damage to eggs or chicks. Believe you should do something to lower the nest either now or later. This generally doesn't bother the adult birds as long as the latest nest is near normal. Joe Huber, Venice, Fl. Charter member NABS, Charter member OBS, Life member OBS Joe Huber... From: "Brenda Walters" brenda.walters"at"mrawct.com I have a bluebird that laid 5 eggs that did not hatch ... she laid another 5 eggs on top of the first 5 ... the second lay did not hatch either. She then went to another box and laid another 5 eggs ... you guessed it! They did not hatch, either. Is this a common occurrence? I have never seen this before. What is wrong with my poor bluebird?? Should I clean out the boxes?? This is soooo sad! Brenda in MS From: "Keith & Sandy Kridler" kridler"at"1starnet.com Keith Kridler Mt. Pleasant Texas From: "Zimmerman, Bet" The Bluebird Monitor's Guide (now my fave) says that it's common
to have 10-15% of eggs not hatch, with unhatched eggs in as
many as 25% of nests in some years. Seems like there are a lot
of posts on unhatched eggs this year--does it look like a bad
one? I had my first unhatched Bet from CT From: "Phil Berry" mrtony8"at"mchsi.com without looking at my notes, I have had easily 40 eggs not hatch this year. Most of these are the second clutch. Most of this time it rained, rained, and rained. However, one box is directly in front of a large commercial sprinkler (golf course), which pours water in the box on every cycle (I did not realize until a week ago what was happening). I watched it drench the door and opening. When the sprinkler moved away, I cautiously opened it up to see five young birds....with their wings pulled over their heads!!! They apparently grew up learning to hide when the water comes at them. This box is on its third clutch this year and all eggs have hatched and fledged. So maybe my theory is "all wet." Phil Berry Gulf Breeze, Florida ... From: "emcooper" emcooper"at"bayou.com There's definitely been more infertile eggs this year on my trail. The weather has not been as hot as previous years. There's been three clutches of five eggs where only one hatched. In one, they removed the 4 eggs and the dead baby and reworked the nest and started over. It is their third cycle and they have 4 babies as of two days ago. Evelyn Cooper Delhi, La. Louisiana Bayou Bluebird Society Bluebirds along the bayous.....where we lend a helping hand! www.labayoubluebirdsociety.org ... From: Lynn Ward lWard"at"pmai.org I also have had more infertile eggs on my trail this year than ever before. The weather this nesting season has been about the same as last. Cold, wet spring that quickly turned into a very hot & dry summer. We're just now getting enough rain. I've also had a very high mortality rate this year in tree swallows about to fledge. They'd all be alive & well the day before fledging & after fledging, in many of the boxes, there would be at least two dead. It's been kind of a strange year. Lynn Ward ... From: "Jim & Ann" jimnann"at"midwestinfo.net I have only found 1 EABL egg that hasn't hatched this year. This even though we've had more rain than we've had in several years. I just yesterday checked my trail & have two nests with four hatchlings in them & one nest of five eggs with mother sitting on it. Also one nest of tree swallow eggs with mama chirping from a close branch as I checked the nest. Jim Koehler Miltona, MN From: "emcooper" emcooper"at"bayou.com I had two members contact me yesterday about having so many infertile eggs this season. One only had one pair and both clutches of 5 eggs were infertile. No babies at all for her this year. (southern part of the state) Another, (northeastern part of the state) said his second clutch of 5 were infertile. I have not tallied mine for this year, but did have three clutches of 5 that only one hatched out of the 15 eggs. Also, had others that had infertile eggs. These two members asked me if the very rainy season we have had could have contributed to it as their nests got wet. My boxes stayed dry. Does anyone out there have any comments as to why this season there seems to be more infertile eggs for some people? Evelyn Cooper Date: Thu, 24 Jul 2003 11:59:24 -0700 Linda Violett - Yorba Linda, Calif. Evelyn and All, Nests with only one or two chicks seem to be in localized areas. Three occurred recently in a cluster of adjacent boxes on one portion of a greenbelt (homeowner chemicals or site conditions are suspected since other city parks/greenbelts were not affected). Pockets of boxes with low hatch rates also occurred in a generalized area of the golf course where a reconstructed fountain/lake has a new unnatural greenish hue in the water. I suspect chemicals have been added to the fountain water but that is a low-priority question that will have to wait because swarms of bees on the golf course trail are causing far more havoc than low hatch rates. This morning I took a down a nestbox swarm from the golf course . . . and found another nestbox full of them on the way out. The golf course is very cooperative and has just removed swarms out of their natural tree cavities and they will let me "pair" boxes next year to (hopefully) siphon bees away from active boxes. So the "chemical" question will be kept on the back burner. ... From: "Dan Hanan" danhan7"at"earthlink.net I am also experiencing a lot of infertile bluebird eggs on my trail. The trail has 24 nestboxes and is located some 35 miles Southeast of Austin, Texas where the daily temperatures will get up into the high 90's or low 100's. There have been 36 infertile bluebird eggs out of 70 in the past 14 clutches. All 28 eggs were infertile in four nests. Two nests, with 9 eggs total, hatched one baby in each. There are presently four active bluebird nests with 4 babies and 12 eggs, where 5 of the eggs are surely bad as siblings have already hatched. Also, one of the four nests, with 4 eggs, appears to be abandoned. So far and not counting the present active nests, the fledge rate has been 33% and the bad egg rate has been 51%. Four babies have been lost, two to ants and two just disappeared. No embryos were found in any of the bad eggs. It appears to me, that a number of the adult birds are infertile. The good news is that more babies have fledged this year than in any of the past years. So far 23 EABL, 6 TUTI, 7 CACH, and 5 CARW have fledged and this is attributed to increased number of nestboxes. Dan Hanan ... From: "Keith & Sandy Kridler" kakridler"at"1starnet.com Keith Kridler Mt. Pleasant Texas Remember that on average that only around 80 out of 100 eggs under ideal conditions are going to hatch. Add in the number of females that get killed during the 13 days of incubation or the ones who abandon their clutch due to interference or predation and it is a wonder there are any birds out there singing at all! Eggs are very fragile and it only takes a little contamination of some common chemicals that a female bluebird can pick up on her feathers during bathing in a contaminated puddle in a yard or parking lot and transfer to the eggs. Just as we humans can apply nicotine or birth control patches to our skin and absorb the chemicals so can the developing chick within the egg shell! We have made tremendous break through in the chemical industry and the field of genetics that allow us to use more chemicals on more acres of crops and yards in the last few years. For example 68% of the 75 million acres of soybeans planted this year in the US are genetically altered so they can be sprayed with the herbicide ROUND-UP instead of using more expensive manual cultivation to control weeds. There were only 70 million acres of corn planted this year in the US but 38% of them are genetically altered for either insect control or ROUND-UP resistance. Try to remember that every human you see or meet requires 1/2 acre of either corn or soybeans that are kept weed free and insect free here in the US every year of their lives! We demand our farmers to produce bigger and better tasting, better looking produce with NO worm holes or blemishes! Try to remember that homeowners/non-farmers are using just about 1&1/2 times the amount of herbicides, fertilizers and insecticides that are being used by all the crops in the US. How many acres of grass are we fertilizing, treating with weed killers and insecticides and mowing weekly to maintain a "beautiful" yard? Just for fun ask your neighbors or co-workers if they have any insecticides or herbicides. As a Texas Master Gardener I get a lot of calls and you would be amazed at the types and amounts of chemicals in some garages that will end up on nearby yards. Yes we are still finding DDT that is made by American owned companies and sold to or made in Mexico and smuggled back across the border! If you had to collect rain water for your personal drinking and bathing from a shallow hole in your yard would you be applying herbicides and insecticides to create aesthetically prettier mono culture yard plantings? Well larger and larger numbers of infertile eggs showing up in the more urban areas of the country might be a good indicator of what humans can expect to happen to them and this to me is the reason more of those on this list should be contributing their backyard nesting data to Cornell's data pool. Without widespread data collection as proof we are just whispering warnings into the wind. By contributing golf course data from nestboxes and comparing that to urban areas and high use crop land we can actually determine the health of our environment in different areas of the country. It is actually far more important for say 100 backyard bluebirders with 15 nestboxes in their yard or in their neighbor hood to join Cornell and add their data than a single large trail with 100500 nestboxes. You can make a difference and it will only require you to give up the monetary equivalent of two "burger basket meals" (or one batch of mealworms:-)) and the commercial time in a normal two hour movie. This is a small price to pay for leaving this world a better place for our grand children! KK From: "Zimmerman, Bet" Might want to see http://www.birds.cornell.edu/publications/birdscope/Summer2001/pesticides.html (make sure you copy and past in the entire address) for a study Cornell did on unhatched eggs and pesticides. Also, they are starting a pilot study this year with The Birdhouse Network data and pesticides. Finally, see excerpt below from another analysis of 1999 data. Anecdotally, it seems like some people are saying they seem to have more unhatched eggs than previous years this year.... Bet from CT Nest-Box Data Reveal Surprising Results BY Tina Phillips _____ Please cite this Page as: Phillips, T. 2000. Nest-Box Data Reveal Surprising Results. Birdscope, Volume 14, Number 3: 3,14-15. _____ EXCERPT FROM A summary of 1999 data from The Birdhouse Network Among bluebirds, unhatched or infertile eggs occur in approximately 10 to 15 percent of nests. It92s surprising that TBN participants reported unhatched eggs in89 more than 25 percent of their nest boxes for all three bluebird species. Mountain Bluebirds showed the highest percentage of boxes with one or more unhatched eggs (28.7 percent), whereas House Wren nests with one or more unhatched eggs totaled 17.38 percent. Typically, eggs don92t hatch because one parent is infertile, the eggs are poorly incubated, or the shell is weak and doesn92t allow the embryo to develop properly. Most often, inadequate incubation occurs because of inclement weather, disturbances to the nest, or because the female is young and has had little incubation experience. As nest-box monitors, there is nothing we can do about infertile parents. We can, however, monitor boxes sparingly (once or twice weekly), avoid early morning checks (especially during incubation), and always avoid checking boxes in bad weather. These precautions will minimize disturbances to a nesting pair (especially an incubating female). ... From: NYSassy1005"at"aol.com BB List From: Elaine Piligian [mailto:birdlady5211960"at"yahoo.com]
Last month I wrote about my dilemma of having a pair of EABL with 5 eggs that did not hatch. I was advised to remove the nest with the unhatched eggs and let the EABL pair start again. I was so excited when, within a few days, the had built a new nest and had laid 5 eggs once again. Well, here we go again. The 5 eggs are sitting in the nest, still unhatched, and they should have hatched by now. The mother and father do go in and out of the box, but the mother is not staying there constantly. What should we do now. I guess we have an infertile male, right? We are now at 20 days after the last egg was laid. Is it too soon to remove the eggs and nest? It's so sad to believe that we won't have any baby bluebirds to enjoy this year. Elaine Piligian Harleysville, PA From: KCBSP"at"aol.com
[mailto:KCBSP"at"aol.com] Aww Elaine, it happens sometimes. I know of one other person that had this happen for several years in her yard. Finally I guess something happened to the male or he moved on. If you are sure of the dates I feel you could remove the eggs and nest. Third time is a charm people used to say, hope so for your sake so you can enjoy them there. Sometimes there are reasons why the birds are infertile. Look around and watch what is going on in your area if you notice anything else awry. Kathy Clark, New Cumberland, PA From: Joe Huber [mailto:hubertrap"at"webtv.net] Hi Elaine, If the female has not sat on these eggs on a regular basis, they will not hatch. Eggs can remain in the nest many days before incubation starts and still be fertile. Have you tried the feeling of eggs to see if they are warm. There is no real way to advise you yet since not much is known for sure about incubation of these eggs. I would wait a little longer to be sure eggs have been incubated by the female. Do you have other boxes in the area? This may be a good idea in case they need to start another nest. Good luck on the results. Joe Huber Venice Florida From: blmyers"at"iupui.edu [mailto:blmyers"at"iupui.edu]
I had my second clutch of eggs hatch today. I had five eggs in the clutch, and I now have 4 newly-hatched EABLs. I'm not sure if the 5th egg is a dud or not--how long should I give it, and if it is a dud, should I let the parents take care of it, or should I dispose of it? Betsy From: Dottie Roseboom [mailto:rosedot"at"mtco.com] Many times one egg will be late in hatching, especially if you just happened to be monitoring as the hatching was happening. Some people say that this is because the female started incubating the night before she lays the last egg. I'm not sure if that is the reason all the time, as I've seen a late hatching in clutches that I know were not being incubated until several days after the 5th egg was laid. And this year, our area had very strange weather, with an exceptional warm spring. I've had 3 nests to have 1 egg to hatch late, and one nest had 2 late eggs. This is a higher number than in most springs. Personally, I would leave the egg for several days, before removing it. This ensures that it isn't just a late hatching. And the parents might remove it. My philosophy is to allow the parents to do as much as they can, before I interfere. Other monitors remove "duds" within 24 hrs, because of possible breakage. If the weather is cold or rainy, I don't like to open the nestbox just to remove an egg. If you do remove the egg, try to dispose of it where snakes, cats, or raccoons will not find it - no sense in training them to associate your yard with free eggs. BTW, many late hatchlings will fledge several hours later than the earlier hatchlings. Although this may be a hassle for the parents, it gives us a wider time span to "catch" the fledging :-) Dottie Roseboom Peoria IL (central - zone 5) From: blmyers"at"iupui.edu [mailto:blmyers"at"iupui.edu]
I appreciate everyone having an answer for me for the supposed "dud" egg; however, my question got answered for me before I had a chance to log on today. I have 4 visible newborn EABS in the nest, and now no extra egg. I didn't want to pick them up, etc. to count them, so I tried to get a head count from what I could see. I can actually hear them make noises if I listen closely! They're so darned CUTE!!!!!!! The parents have been in and out of the box all day from what I could see... I also think I saw one of the newborns' siblings from the first clutch around the box as well. From: Dottie Roseboom [mailto:rosedot"at"mtco.com]
And the "invisible" egg is usually what happens in late hatchings. Be patient - the dud egg might have hatched, and you just can't distinguish all 5 babies yet. I have been fortunate this year to have had 8 chickadee eggs, which I could tell for sure that 6 hatched. After 5 or 6 days, I realized that there were 7 babies. Could I hope that the 8th one was also tangled up in there? Sure enough, by day 11, they were all circled-up, 8 beautiful little heads. Yesterday, I just confirmed that all 6 bluebird eggs also hatched (11 days). Sure is neat to be able to finally verify that the "dud" hatched. I feel that it's safer NOT to handle the chicks - so I just wait until the babies straighten themselves out. Patience is helpful in monitoring. (BTW, in most areas, it's illegal to handle chicks without permits). Have fun watching the little ones. Dottie Roseboom Peoria IL (central - zone 5) From: Horace Sher [mailto:hjsher1"at"yahoo.com]
Hello.....Prior to this year, I hardly ever had an infertile EABL egg in any of our neighborhood clutches...1st or 2nd cycles. But this year, almost every one of our EABL clutches had an infertile egg. What's going on? Have other people noticed the same thing or trend this year? I wonder if there's something in our environment..like more pollution or something else causing this? Any concrete or factual ideas? Thank you for any responses.... Horace in NC. From: Dottie, Hickory Hollow, Brown County,
Indiana [mailto:yumyumkatts"at"voyager.net] I have had infertile BB eggs before so this year is not unusual for me. This year I have had three infertile BB eggs--so far. Actually, this year is the least number of infertile BB eggs here. Dottie, Hickory Hollow Brown County, Indiana From: Keith & Sandy Kridler [mailto:txbluebirder"at"sbcglobal.net] Normally only about 80% of eggs on average will hatch. So if you have 1 out of 5 eggs that do not hatch this is actually perfect "average" hatching percentage. I have 19 pairs of Cornell's data loggers in bluebird nests with eggs this morning and two are in nests being incubated with only two eggs and one nest only has three eggs. None of these 19 bluebird nests have 6 eggs. One had a cowbird egg with four bluebird eggs but I removed it to make room for the data logger placed in the nestcup. This is the fifth cowbird egg this year in bluebird or flycatcher nests in nestboxes and NONE of the other four cowbird eggs hatched that I left in the boxes. I pulled some House Sparrow nests this week that had 8 eggs in a nest and two with 7 eggs in the nest....I hit a RECORD number of sparrow eggs in a single nest at the Frito Lay warehouse where they feed broken bags of chips to the sparrows......FOURTEEN eggs in a single nest!!!!! It actually looks like the same female laid all of the eggs due to size and color but it is two or three sets of eggs.....SO House Sparrows also have large numbers of infertile eggs sometimes. I have a photo of these 14 House Sparrow eggs sitting on a shop rag if someone wants it for a web page. These eggs are interesting because for here they are VERY light colored compared to most House Sparrow eggs. PS this means that some of these boxes were not monitored correctly in several months and the world did not end....yet:-)) KK From: markmele"at"att.net [mailto:markmele"at"att.net] Sent: Thursday, June 24, 2004 7:53 PM Subject: RE: 1 infertile EABL egg/nest I had one EABL pair that laid 5 eggs, and only one hatched. It does happen from time to time. Mark, Hillsborough, NJ From: Blubabies"at"aol.com [mailto:Blubabies"at"aol.com] From: Haleya Priest [mailto:mablue"at"gis.net] I've been fielding questions off list from 2 different folks who insisted they eggs that have been in the nest for over 20 days. They are SURE they are no good and should toss. I can't say enough about being careful about tossing what seem to be infertile eggs!!! I've seen it happen in the early spring also - sometimes it feels like eternity since she has started to lay - - - but it just isn't worth tossing eggs without having CLEAR records - not just memory - of when they were laid. Anyway - I say this because I told one of these folks to wait 5 more days before she tossed the eggs. She just emailed to say she opened the box today -and there are 2 newborns!! And if I can add - - if any newbies need a monitoring form where you can really record the important data of the nesting cycle you print forms from http://www.massbluebird.org :-) H From: Dottie Roseboom [mailto:rosedot"at"mtco.com] Haleya, Great advice! And even if people are absolutely sure that 20 days have passed, another 3 - 5 days isn't that much longer to wait before discarding eggs. In past years, I've had friends with very late-to-hatch eggs. They were so thankful that they had not pitched them. I also think that monitors need to be careful about tossing an egg to quickly, when the others have hatched. This year, the list saw pictures of chicks that hatched days apart. I just experienced this last week - 4 bluebird babies hatched over 3 1/2 days. Just like people, birds don't always follow "the norm". Dottie Roseboom Peoria IL (central - zone 5) From: Keith & Sandy Kridler [mailto:txbluebirder"at"sbcglobal.net] It was great to meet Tina at the NABS convention along with MANY new bluebirders. Sandy and I went to our first convention in 1984 at Jackson Miss. and that was the first time we could exchange information in real time and NOT have to wait days or weeks for a letter or three months for the next Sialia to come out.....We are SO spoiled today by asking a simple question and getting answers from all over the country in a matter of hours! Or able to take a picture and "develop" and share it immediately on the computer instead of waiting for two weeks for the "slide" film to come back before you even know if you caught the bird at all! Anyway lets get back to Tina and research! She mentioned infertile eggs in bluebird nests as the summer progresses seems to increase and that they might do "research" on this next year where you watch the nests closely and mark each egg as they are laid to determine if it is the first eggs laid in a large clutch or the last eggs laid that do not hatch! I always assumed it was the hot Texas summers that cut down on % of eggs hatching but June and the first week of July was cool this year and by using temperature data loggers in all types of nestboxes is showing that these eggs are NOT getting so hot that they cook but there must be other reasons for lower hatching percentages/lower fertility. OK Tina mentioned that there are between 500>600 people on this list now and MANY are able and WANT to check their backyard nestboxes EVERYDAY:-)) We are just NOW getting into the heat of summer and it would be perfect timing to start this sort of research now and work out the problems for next years research! As Ann Wick says, "First of all we must do NO HARM to the birds." So you would have to be able to pick up fragile bird eggs and mark them without breaking them.....Practice on House Sparrow eggs would be good....Try to borrow these from your neighbors:-)) Someone told me about marking eggs long ago and they used a soft, felt tipped pen and they put one dot on the big end for the first egg two dots for the second and they used the dot layout for dice up to the sixth egg laid. OK Tina what type of pen ink would not hurt the developing embryo? Would an indelible black ink pen like a Sharpie work? How do Professionals mark bird eggs? Bluebirds normally lay their eggs in the morning so being able to check the box and mark eggs from noon to just before sundown would be an advantage. As the eggs hatch you would be able to tell which egg hatched in what order and you could report to Cornell by e-mail and we would know just how long it actually takes for an egg to hatch in what order in different parts of the country..After several days past the last egg hatched the "bad" eggs could be broken open to record the number that were infertile and the number that had a developing embryo that did not break out of the egg and record what day the egg was laid. I would imagine Tina and Cornell already have this idea pretty well thought out! Anyway this is the PERFECT research for those with backyard nestboxes as many of my boxes are 20 miles away! KK From: Evelyn Cooper [mailto:emcooper"at"bayou.com] Keith, I had already noticed the increase in infertile eggs on the THIRD nesting cycle. That is, the third time a nest was made in the nestbox. I have two that only one hatched out of four and one that two hatched out of five. Others are being incubated. I too thought it was the terrible heat that cooked them, but like you said, it has been very cool for this time of the year. That is until about three days ago and now the Bluebirds have started hanging to the woods. Even around 9:00, I don't see them out everywhere as usual as it is already hot here by then. My trail is a little over two miles, but I try to check it every other day. I would really like to know who professionals mark the eggs. I would be rather apprehensive about it. They are so very fragile. It surely would be interesting for us to take part in. However, mine have all been laid and are being hatched on the third cycle for this year. I am saving some eggs for display at our meeting. (Got the Federal Permit, so don't anyone get excited!) Evelyn Cooper Delhi, LA From: Tina Phillips [mailto:cbp6"at"cornell.edu] It was wonderful to meet you and all the other dedicated NABS members. I hope everyone enjoyed their visit here despite the rain...which has become more relentless since Monday. I have spent the morning talking to Caren Cooper and Andre Dhondt about the potential for pilot testing the sequence of egg laying by marking eggs. We have agreed with Keith that if people are interested, they could begin helping us develop the protocol for marking eggs for next season. Many scientists use markers to sequence eggs, with no apparent ill effects on the eggs or developing embryos. Keep in mind that only small dots are being applied, using very light pressure. For the remainder of this season, this is what we recommend: If you are interested in conducting this pilot study, please contact Caren Cooper at cbc25"at"cornell.edu as I will be out of the office from July 16th to July 30th. Once you contact her, she may have more instructions or suggestions for you to follow, particularly in terms of recording the sequence in conjunction with data loggers, and reporting results back to us. Even if you are not participating in the data logger study, you can help us develop the protocol for marking eggs. Your feedback will help us refine the protocol which we hope to implement in the 2005 nesting season. Thank you in advance for your participation, and thanks Keith for seeing an opportunity and making it happen! Sincerely, Tina Phillips From: Evelyn Cooper [mailto:emcooper"at"bayou.com] ...I have one female that has been incubating since July 9th. Today, the eggs were still warm. My husband thinks I should remove them, but I just don't have the heart. Any suggestions? Evelyn Cooper Delhi, LA From: Dottie Roseboom [mailto:rosedot"at"mtco.com] ...IMO, if the eggs are still warm, I would leave them. The only problem I could think of would be that an incubating female is at a slightly greater risk of snake/HOSP predation, but then again, she would be safer from hawks :-) As long as her earlier fledglings are being fed, I can't think of any reason to be in a hurry to remove the nest/eggs. Probably too late for a 4th nesting? Dottie Roseboom Peoria IL (central - zone 5) NABS member From: Evelyn Cooper [mailto:emcooper"at"bayou.com] Well, she's pretty safe on both counts from snakes and HOSP. I don't have HOSP and there is a Ron Kingston Guard plus a five gallon bucket top above that on the nestbox she is using. Yes, it is too late for us in my part of the state to have a fourth nesting. I've never had but three. They have four in south LA. Yes, it is really something seeing them. However, this is the time of the year they hang to the shade in the woods a lot. Come middle of Sept., I will see them line for several miles on the power-lines down Cooper Rd. Can't wait!!! I think I am just trying to convince my husband that it is not wear and tear on her to do it. I will tell him what my good friends on BB-List say. :<)) Evelyn From: Dottie Roseboom [mailto:rosedot"at"mtco.com] Yep, I was pretty confident that you would have snake guards! I had also considered the "wear & tear" aspect. IMO, egg laying is more stressful than the actual incubation, especially, since you have the solar protection. And sometimes, when a female loses eggs that she is still attached to, she'll attempt to lay more eggs, creating undue stress. Sometimes, we disrupt a nesting cycle, and we might not even see the consequences, especially if the female starts another nest in a different location. (also understand about the convincing - let's see what some other thoughts are) Dottie Roseboom Peoria IL (central - zone 5) From: Chris Nordone [mailto:csnpt"at"comcast.net] Sent: Monday, August 16, 2004 7:30 AM Subject: Unhatched eggs ... The bluebirds in my yard have finally left their nest of unhatched eggs (18 days). This was their second clutch of eggs that hasn't hatched. As soon as their first eggs didn't hatch, they switched to another bluebird box I have and built a second nest and promptly laid eggs there. I was so hopeful for them the second time around. I'm curious to know anyone's opinion as to why these eggs haven't hatched this year? This has never happened to me with my recent years of experience with bluebirds. To have two clutches of eggs not hatch seems to me to be unusual. Is it? Are there any documented reasons in research as to why this occurs? Thanks for your thoughts. Chris From: Autumn L. Kruer [mailto:autumnk"at"iglou.com] Sent: Monday, August 16, 2004 8:13 AM Subject: RE: Unhatched eggs I thought my last nesting here wasn’t going to hatch simply because a pair of house sparrows were harassing the bluebirds so much that they were spending more time fighting them off than sitting on the nest. They had previously tried to nest in an adjacent box and gave up and switched boxes because of this. After I shot the male house sparrow, they settled comfortably on the nest. Don’t know if this is your problem, but watch the box carefully and see if something is distracting them. Autumn in Kentucky From: Lawrence Herbert [mailto:lherbert"at"4state.com] Sent: Monday, August 16, 2004 8:13 AM Subject: unhatched eggs I have regularly noticed over the years that there seem to be more abandoned complete clutches in the last cycle than at other times. I don't have an explanation, nor have I read one that I can recall. Maybe the parents just run out of energy to deal with it..... Good birding, Larry H.
From: Dottie Roseboom [mailto:rosedot"at"mtco.com] A few weeks ago, we had several posts regarding nests of infertile eggs. Some people were wondering how long to leave eggs that might have been abandoned. I believe that someone also wondered if eggs should be removed, after a certain length of time, even if they were being incubated. Through phone correspondence with Herb Unkrich, I learned how he determines if bluebird eggs are infertile. After examining 17 unhatched eggs, he observed that infertile eggs have 2 different shades of blue coloring. Imagine a ring bisecting the circumference of the egg. The upper half of the egg will be either a darker or lighter shade of blue than the lower half. The 2 colors met, forming a distinct ring around the middle of the egg. He candled these eggs and found them to have no development. A few of the eggs were also opened to verify the candling technique. If other monitors can collaborate Herb's findings; 2-toned eggs could be a helpful clue to remove infertile eggs, allowing bluebirds to quickly re-lay. I would be interested in hearing if anyone has ever noticed 2 distinct shades in eggs that hatched. Herb has 45 nestboxes and fledged more than 250 nestlings this year." Dottie Roseboom Peoria IL (central - zone 5) NABS member From: Chris Nordone [mailto:csnpt"at"comcast.net] Thanks everyone for your ideas about eggs not hatching. I guess I will admit to not being sure that this is the same pair that earlier in the season left unhatched eggs also. Someone suggested maybe toxins in area.....i.e.....lawncare. I do have a company that fertilizes our lawn...have had for a number of years and this has never been a problem before. But now, I will stop them and see what happens next Spring. Thanks for that suggestion. I was wondering about that myself and feeling guilty that I might have contributed to the problem. I did notice what Dottie, from Peoria, has mentioned......two toned eggs!!! There was an actual ring around the eggs that I noticed from the first group that did not hatch. There is a slight color differentiation above and below the ring. I haven't been able to bring myself to check this second clutch of eggs yet....I still feel so bad. I am not involved with monitoring a lot of bluebird houses, although I wish I was. I only have two boxes in my yard and this year there were no bluebird babies at all. Chris Chadds Ford, PA From: Keith & Sandy Kridler [mailto:txbluebirder"at"sbcglobal.net] ....On average only about 80% of all bird eggs laid will hatch under ideal circumstances. Ever hear of humans that try to have children only to find out that one or the other of the pair are sterile or the ones who go ten years or more before conceiving their first child? Then we all know other couples who are enjoying the birth of their 17 th child with an average of 2.4 children per couple in the USA. We have a man on the list asking about a third nesting of bluebirds in one year near Youngstown Ohio. Our family moved from near there in 1964 and there were NO BLUEBIRDS left in Northeast Ohio by about 1957 to even nest once! It was believed that widespread spraying of pesticides on crops and severe winter weather combined to thin out populations of birds then. Today homeowners in a strange quest to have the thickest, greenest one single species of grass growing in their yard often pay complete lawn care companies to fertilize, and apply pesticides and herbicides and fungicides regularly to their yards so that the homeowners can pay the lawn care specialists to mow these fast growing lawns even more often:-))) Fertilizer does not harm birds but monoculture of one grass with no weeds limits the numbers of insects in a yard. Pesticides temporarily kill out some species of insects, bacteria and even single cell creatures in the grass and soil. Some insects take years to reach adult hood and generations of insects can be wiped out in a single application. Herbicides are often "safe" in tests but again they limit the numbers of certain "weeds" that many species of fungus, bacteria, and insects and animals depend on. Did you know that ALL commercial lawn grasses are imported alien "weeds" from overseas? Kentucky and Canadian bluegrass is actually from Moscow! Have you ever seen a southern box turtle munch down on Bermuda Grass? Then we sometimes combine two common, "safe" weed killers like 2-4-D and 2-4-5-T and you end up with a super herbicide we used in Viet Nam called "Agent Orange" that affected mammals nervous systems. Today there are dozens of herbicides routinely being combined in spray tanks with fertilizers, pesticides and fungicides to "save time" in applications...These are very reactive chemicals! Few people EVER ask what is being sprayed or applied to their lawns.....or their neighbors lawns.... Fungicides help in keeping the lawn grass healthy but they kill ALL types of fungus like mushrooms and puff balls and the millions of species of related organisms we need to help break down cellulose from lawn clippings to leaves to wood fiber.... In thirty years and hundreds of millions of $ later we have only increased the numbers of ONE PERCENT of the endangered species listed in the USA but we cheerfully spread chemicals in our backyards that wipe out entire families of living organisms.....Most have never even been named yet. I NEVER wonder WHY nests of bird eggs don't hatch but I am ALWAYS amazed when even one egg hatches! KK From: Lynn Ward [mailto:lWard"at"pmai.org] Hi Chris, I have a friend who is a brand new bluebirder this year. I put up four boxes for her and she got a bluebird pair right away. It was a terribly disappointing nesting season for her... The pair laid five eggs the first time that didn't hatch. She removed the nest & eggs and they proceeded to build another nest right away. Out of four eggs, only one hatched. They built a third nest after this one fledged and laid four more - none of which hatched again. I felt bad for her but at least she got to see one nestling out of all those eggs! There didn't seem to be any reason for the eggs not to hatch as she watched this box closely and regularly. I personally have never experienced such a thing - just the normal occasional infertile egg - so I really didn't know what to tell her. Lynn Ward South Central Michigan From: lviolett [mailto:lviolett"at"earthlink.net] Regarding the removal of unhatched eggs, the topic should really be divided into two distinct segments: 1) Tossing out entire clutches of "old" eggs based on guesswork; 2) Removing unhatched eggs a week after the rest of the clutch has hatched My trail fledges over 400 Western Bluebirds each year and I no longer remove eggs unless week-old nestlings are also in the nest. Obviously, we don't want old unhatched eggs to break in the nest alongside active nestlings and attract predators or infestations. Westerns on my trail don't seem confused by unhatched eggs and I don't feel there is any benefit in removing whole clutches of eggs. Westerns will sometimes build a new nestcup over old eggs, they are capable of removing eggs and/or small dead young chicks, or sometimes an unhatched egg is found in the nest after the fledge. I tossed out a good clutch of eggs (developing chicks in them) during my early monitoring years (and KK has done the same); it would be interesting to know the total number of viable eggs are tossed out by our group each year. From: Haleya Priest [mailto:mablue"at"gis.net] I think Linda has something here. I also think folks toss out viable eggs without thinking twice. I almost lost a clutch this way - a cold cold cold day and the eggs felt cold after having been warm. I was sure they abandoned - but after taking the whole nest out in putting it in the back of my car - - about 1.5 hours later I thought - I better put them back in the box. I did. The next morning they were warm again. I was lucky!!!!:-) H From: Keith & Sandy Kridler [mailto:txbluebirder"at"sbcglobal.net] Dr. Patricia Gowaty in the southeast has spent years studying bluebirds and the things that effect the % of eggs hatching. They have done a lot of research into the % of the number of females that have multiple breedings outside of their own mate. (DNA testing of young in the nests.)The % of eggs in a nest that are NOT related to the female who incubates the eggs. AND many other aspects of breeding populations in different areas and age of the birds. This is ongoing research still. Maybe Tina Phillips can tell us where to read up on this research? Cornell, the sponsors of this list have ongoing research right now into the variations of nestbox temperature and the duration and quality of incubation temperature of different female bluebirds. NONE of this is cheap and $ normally limit the scope of the research. I have helped with the temperature data loggers and ANY of you could buy your own set of temperature data loggers and a cheap computer scanner for these and help send in more data to Caren Cooper this next year. I think you can buy a set of Temperature Data Loggers for about $20 a pair and the scanner and software to program and download the data logger is about another $25 or so from Texas Instruments. They are supposed to last about three years and all 20 of mine are still working great! (This is the cost of how many mealworms:-))) You and I can be more efficient with money and often get better or more results than a totally funded government program with US money. For example Eider ducks in Alaska are in severe decline. The Stellar and Spectacled Eider are on the threatened list and the governments Endangered Species department decided to capture and breed ten pairs of Steller's Eider ducks this year. (There are approximately 500 breeding pairs in Alaska.) They captured and penned up the 10 pairs of ducks at a cost of "only" $818,000.00 spent so far in 2004 and NEVER got even one duck to lay a single egg!!!!! The researcher in charge has called this a "Great Success" and US will spend another million $$ of the $30 million annual budget of the Endangered species funds on this project again next year:-))) Remember there are now 1,300 plus species on the endangered list and thousands more on the threatened list with tens of thousands on the different watch lists.....This means if we are going to save these species we need to get PERSONAL and get out and help directly with some of these projects. Since bluebirds are our subject and everyone wants to know why their eggs don't hatch maybe Tina Phillips can spell out how more of us can donate data to Cornell, see if we can earmark $ to expand Caren Cooper's work there at Cornell or get more states or individuals to buy their own equipment and submit data to Cornell for this research. Remember the Eider ducks now and think that after millions of $ spent to get the first eggs next year (They hope/I hope.) The researchers will still have to do "research" as to why "many" of these expensive eggs don't hatch.....Maybe bluebirders can help save them a little money but more importantly get more eggs to hatch. KK From: jwick"at"tds.net [mailto:jwick"at"tds.net] ........my approach Linda and list members............. I use exactly the same approach as Linda with regard to removing unhatched Eastern Bluebird eggs. Unless a nestbox has been checked every day, one really does NOT know if the eggs in a particular nestbox are the same eggs laid originally. Although they MIGHT be the same eggs she laid in the original clutch, they MIGHT NOT be. Let me explain: In my own yard nestbox 2 years ago, I had a female lay a clutch and incubate those eggs for nearly 20 days. She then removed them and began laying again. This clutch hatched. If this box had been out on one of my trails, I quite possibly might have assumed the eggs were infertile as there had been eggs in that nestbox for so many days. Therefore, as long as the female is present and still incubating I do NOT remove clutches of eggs. Like Linda, I do remove unhatched eggs after the young in a given nestbox are a week old. Often unhatched eggs will have been removed by the adults as the nestlings develop. Once in awhile, I remove an unhatched egg buried in the nesting material when I routinely band the nestlings at 11-12 days of age. My personal rules insofar as bluebirding continue to be: 1) Do no harm. 2) Expect the unexpected. 3) Never say never :) Ann Wick Black Earth, WI where a female in one of my nestboxes laid her last egg on August 8th! (Rules #2 + 3 apply!!!!) From: Paula [mailto:PaulaZ"at"columbus.rr.com] ... Sorry about your unsuccessful blues this year. A couple of suggestions if I may, and some may disagree here. Regarding lawn fertilizing, I fertilize my own grass. I only use granular fertilizer and never apply insecticides or other broad leaf weed killers to the lawn. This is what I do. The bluebirds seem to thrive with this practice. I have a friend who has beautiful lawn and she does same thing, but also puts down granular grub control as well. Neither of us have had a problem with infertile eggs or losing any young. Here is my second suggestion. Try to start a bluebird trail. You sound motivated and know what you are doing. Find a local park, golf course, cemetary, church yard, school yard, etc. and call those in charge. See if they will let you put up some boxes and monitor a trail. This fall would be excellent time to install boxes or you could wait until early spring. I did this at local park 3 years ago and am loving it. The EABL and TRES seem pleased too. The HOSP are not so pleased, but that is fine as well. Paula Z, Powell (Central) Ohio From: Paula [mailto:PaulaZ"at"columbus.rr.com] Keith et al, Great post as usual... We live in one of those suburban subdivisions with the green lawns. We have been here for 17 years now and it is interesting that the lawn care companies do not serve most of our neighbors where we all had them years ago. It is so much cheaper to fertilize the grass yourself. It is simple and you can apply it right before the rain is forecast so it does a wonderful job. You can also hold off on fertilizer applications during droughts so you don't stress the grass even further. I have been fertilizing my own grass for over 10 years now and it looks better than most of the lawns that have lawn care companies. I have no need for herbicides because I am an old weed digger from way back. We don't have that many weeds actually, but I even dig up dandelions while others usually spray for them. Crabgrass does not seem to be a problem so why would I ever put down a preemergent - makes no sense to put down chemicals for problems I don't have. Now the one little gliche I have observed since I have all these bluebirds in my yard is that every spring, I find baby poison ivy plants EVERYWHERE. The EABL are eating the berries and planting them all over the yard when the seeds come out the other end. So now I just make sure to wear the garden gloves when I pull weeds - no problem here. I had a friend who wanted a box because she had seen EABL in her yard this spring. We both decided against it, however, because her neighbor sprays their yard and house with abandon. The previous year, she had discovered a dead adult EABL in her backyard. After learning about her neighbor's "lawn care" practices, I told her this was almost certainly a poisoning. Even if you don't care about wildlife, what are these chemicals doing to us and those we love? I think about it often when I'm out digging up weeds... Paula Z Powell (Central) Ohio From: Tina Phillips [mailto:cbp6"at"cornell.edu] Sent: Wednesday, August 18, 2004 12:24 PM Subject: Re: Research into eggs hatching Hi Keith, As always, thanks for your insight. You have asked two important questions: 1) how can we learn more about research on egg viability 2) how can people become more involved with data collection. First the egg viability question. There is TONS of research going on right now, thanks to the new advances of DNA fingerprinting, on all matters of breeding biology. Among other things, we are finding that birds thought to be monogamous are not as faithful as previously thought. Extra pair copulations (EPC) are being heavily studied in ornithology, along with egg dumping, egg viability, and cooperative breeding. Additionally, right here at the Lab we can examine the effect of latitude on unhatched eggs without any DNA testing, just by people from all over the country submitting their data to TBN. Caren Cooper has taken the egg viability question to another level by introducing the Incubation and Temperature Study, which continues in 2005 with all three bluebird species and also, Tree Swallows. Keith, I would argue that rather than people buying their own data loggers, and trying to program them on their own without assistance or direction, they should contact us. We have purchased enough data loggers for hundreds of people to get involved. In fact, Caren Cooper has an excess number this year. All we ask is that people sign up for TBN ($15 annual fee) and report their data. There is no extra charge for people to do the Incubation study when they join TBN. But after they join TBN, they need to contact Caren Cooper at <cbc25"at"cornell.edu> to let her know they are interested in the Incubation Study. In terms of where to read up on this kind of research, the Internet is a great place to start. Even better, if you have access to a University Library system, such as I have with Cornell, you can get online reprints of journal articles for free. If you don't have University library access, just do a Google search on phrases like "extra pair copulations", "egg dumping", "sterile eggs" or "egg viability". You can sometimes get articles from well-respected magazines such as Nature. Also, check web sites of ornithological journals such as the Auk, Condor, Ibis, The Wilson Bulletin, etc. You can sometimes download journals directly from their sites. Of course, you can always visit a local library and search for these subjects as well. Now for the second question about getting involved with Cornell's data collection. The important thing to remember is that every single person on this list can and should be donating data to Cornell. There is so much to study from unhatched eggs, to pesticide effects, to food supplementation, and nest-box competitors. BUT, we can't study these topics if we don't have a big enough sample size or our sample is geographically skewed. The strength of individual observations pooled together across the country cannot be underestimated, and this is the power of citizen science. I often get asked "why do I have to pay $15 if I am doing the data collection?" Here is where some of the money goes: data loggers cost us $10 each and then an additional $3 to mail. We also provide paper and online instructions for the data loggers and for participating in TBN. Additionally, TBN members receive a semiannual newsletter, a beautiful color poster of 10 common cavity-nesters, an annual subscription to BirdScope, the lab's quarterly newsletter, a secure place to store, view, and retrieve nest box data online, a list serve to share experiences with other monitors, and their data analyzed by scientists at the Lab. In my humble opinion, I think that is probably worth more than $15. It has always perplexed me why so many people on Bluebird-l, who seem genuinely interested in science and conservation, are not TBN participants. I realize many are NABS members, but I think TBN and NABS are complimentary to one another, and to be involved in science and conservation, nest-box monitors should belong to both organizations. After 8 years of data collection, TBN has nearly 50,000 nesting records of cavity-nesting birds. WE WANT MORE!!! So before I get off my soap box, I will make the same offer I made at the NABS convention: Join TBN for 2004 and 2005 for the price of one year - just $15! This means that you will be able to enter data for 2004 in time for the early bird deadline (Sept. 30), AND data for 2005, in addition to the above mentioned benefits. To take advantage of the 2-FOR-1 offer, I will send another email out momentarily with a form for folks to print off, fill out, and return to the Lab. If you don't have a printer, you can fill it out and send it directly to my e-mail address, or I would be happy to snail mail the form to you. I look forward to hearing from some of you. Thank you in advance for your commitment to scientific research! Tina Phillips, TBN ... From: Chris&Crystal Hill [mailto:crystaljhill"at"msn.com] This being my second year hosting cavity nesters in yard boxes, I had a clutch of five Eastern Bluebird eggs with only two hatching and fledging (July 4th) I am assuming this was a 2nd brood. Last year I had a five egg clutch with all five hatching but with a first egg date of April. All five of my CACH eggs hatched this was my first year to host them. We do not use any yard products. Crystal Social Circle, Newton County - GA NABS member From: Chris Nordone [mailto:csnpt"at"comcast.net] I've read all the posts regarding unhatched eggs and when to move them out of the box, if at all. Because I've kept a journal (I only monitor two boxes, both on my property) I know the eggs in my box are now 21 days old. I thought the blues had left (I haven't seen them for 2-3 days and the mealworms I had put out daily for them hadn't been touched), but today I saw the female in the box!!! I can't imagine that these eggs are viable. Because I'm sure of the date, should I remove eggs at this point?? Or, take the hint from the mother, and let them remain until they have totally been abandoned?? Any advice?? ... From: JOHN & BARBARA SIBIO [mailto:jsibio"at"comcast.net] I lived in a new development in the town of Sonoma, and was the only homeowner who did NOT have a lawn service. My back yard (1/3 acre) was landscaped for the birds with no grass at all, and mostly native plants. I never used pesticides, or herbicides, but my neighbors sure did. I'm positive they had no idea what their weekly service was spreading around the neighborhood. One year, I found a male bluebird dead in the nest, with his wings spread over his dead chicks. No obvious injuries to any. That hurt. Now I'm in another new development and we were able to get a low maintenance front yard in this development, so I don't have to worry about herbicides and fertilizers on my property. Several of my neighbors have the same landscaping, but others have the lawn which is difficult to maintain in our climate. They all have lawn services. One pest control company comes around once a month offering to take care of the lawns and the houses. We have a lot of ants in the area and I see the employees dressed in "moon suits" spraying all over the place. Scary. I take care of the ants myself and find it is an ongoing challenge but one that can be handled without polluting everything. I had two successful nestings this year, and no infertile eggs. I'm concerned about all the spraying that's going on at my neighbors, because we have a year round creek in back of our homes which sits below our property levels. I'm sure there is run off, but we had lots of frogs this spring and many tadpoles well into the summer. I was raised to pull and dig weeds and will continue as long as I'm able! It's good exercise and very satisfying work, but I don't think I'm going to be able to convert any of my neighbors to do the same. Now the county is spraying for mosquito control. Barbara in Cloverdale, CA From: Dottie Roseboom [mailto:rosedot"at"mtco.com] Everyone, just one caution about fertilizers - be sure to read the ingredients! Many fertilizers are now sold with herbicides. And this spring, while shopping at a garden shop, I heard an employee steer a customer toward a bag of fertilizer that now has insecticide!!! He said "While fertilizing your lawn, you can now kill ants, fleas, and ?". Sorry that I don't remember the other insect. Boy, isn't this all we need? Another way to add chemicals to our lives. For everyone living away from picky neighbors, I recommend not to grow a "monochrome" lawn. Dutch clover, and many other small plants provide lots of nectar for many different insects (read "bluebird treats"). Our lawn is alive with beautiful blooms, buzzing bumblebees, small butterflies, dragonflies, honeybees, orchard bees, hummingbird moths, cicada killers, etc. Lawns with nothing but grass, provide few insects for hummingbirds (much of their diet is comprised of tiny insects). Hummers love our yard - even when I forget to fill up their feeders. Of course, these small nectar-producing plants grow great without being fertilized. Beauty is in the eye of the beholder. A even, constant green with no splash of blooms, dancing butterflies, or the gentle buzz of numerous insects, IMHO is soooo boring! And just think, IF we ever sell our house, the new owner will feel so much satisfaction at re-establishing "that terrible lawn". Dottie Roseboom Peoria IL (central - zone 5) From: Dottie, Hickory Hollow, Brown County, Indiana [mailto:yumyumkatts"at"voyager.net] I don't take my sterile BB eggs out of the nest. I leave them in until the babies have fledged and I'm ready to remove the old nest. So far I haven't had any trouble with this practice. If all eggs were sterile, I would remove them after a couple of weeks or sooner if I had not seen the mom. So far, I haven't had that to happen. I did have a nest of five BB eggs that must have been sterile because the mom pushed them down under the nest and then laid more eggs on top. I also left them there until after the BB babies had fledged. Dottie, Hickory Hollow Brown County, Indiana From: Dottie Roseboom [mailto:rosedot"at"mtco.com] Chris, Are you counting the 21 days from the time that the 1st egg was laid, or from when you felt warm eggs (meaning that incubation had begun)? I've seen many female bluebirds take several days "off" after laying the final egg, and before incubating eggs. Because it's so late in the nesting season, I doubt that they would start another nest even if you remove the eggs. Except for eliminating possible predation, I'm not sure why it would be of benefit to remove the eggs???? I don't think that it would be any more stressful for the female to be sitting on infertile eggs, than it would be for her to return to a nest devoid of her eggs. If these eggs were in one of my nestboxes, I would leave them until the blues had not returned for at least a week. Dottie Roseboom Peoria IL (central - zone 5) From: Tina Phillips [mailto:cbp6"at"cornell.edu] Chirs, I can top your story, unfortunately. Just this morning I received a call fro a gentlemen in New Hampshire. He believes that the same female laid a clutch of 5, then 4, then 6, then 6 again, and then 5 eggs for a total of 26 eggs, in one season, all of which never hatched. I have never heard of a bluebird pair laying this many infertile eggs in one season. The man did puncture the eggs and saw that there was no development, not even a blood vessel, which points to infertility on the part of the male, female or both. My instinct tells me that assuming it is the same female, she would be infertile because even though presumed monogamous, we are now certain that even our beloved bluebirds are not as faithful as originally thought. However, I remember a few years ago (?) this same topic arose and someone mentioned a similar circumstance. Keith Kridler had stated that in the case of more than one infertile clutch from the same pair, it is the male who is infertile. I am curious as to why Keith thinks the male would be the culprit in this scenario. As an aside, the issue of egg viability is very intriguing to myself and Caren Cooper. We will be looking at the TBN database very closely to examine geographic and temporal patterns of this phenomenon. Tina Phillips Ithaca, NY From: Keith & Sandy Kridler [mailto:txbluebirder"at"sbcglobal.net] Keith Kridler Mt. Pleasant, Texas Years ago there were not as many pairs of bluebirds floating around so it was probably easier for a dominant male to prevent infidelity between the pairs. Then again this is wishful human thinking and serves little purpose in maintaining the health of a bird species. This is why it is so important for members of this list to take advantage of the two year offer and volunteer to help with some of the egg marking and data logger research over the next few years. There is no way one person can keep up with dozens of nests and spreading out the collected data base over most of North America quickly gives us better results.....Even if you only have one nesting of bluebirds a year in your yard then the everyday data collection you can add is priceless! KK From: EHDerry"at"aol.com [mailto:EHDerry"at"aol.com] Tina and All: A couple of years ago I had two consecutive clutches of infertile eggs. When checked, the 5 eggs showed no signs of any development even after 21 days or more of the female sitting on the eggs. (These were backyard boxes so we could observe the incubation going on.) We were able to determine that it most likely was the male that was sterile as the two clutches were laid by a different female: the first one had been banded and second wasn't. Two days after removing the first clutch of eggs, a female started building a nest in the box 30 feet away. Again 5 eggs were laid. None hatched. I believe it was KK who suggested it was the male who was infertile - so this may be the case you were referring to, Tina. Judy Derry Lockport, NY From: Evelyn Cooper [mailto:emcooper"at"bayou.com] It has been a few days since I checked the last nest that has been being incubated since July 9th. The eggs are now cold, so that must mean she has abandoned them. It is the only nest that all were infertile, three of them. I see no need to be in a hurry to remove them even now. I will at some point. I do remove infertile eggs with nestlings in the same nest because of reports that the eggs have broken and caused problems for them. I give it about 5 days. Evelyn Cooper Delhi, LA From: Dottie Roseboom [mailto:rosedot"at"mtco.com] Sent: Wednesday, August 18, 2004 4:14 PM Subject: Re: Unhatched eggs & chemicals For people who want the "perfect lawn", Paula has a good way to go about it: hand-pulling weeds and using a granular fertilizer. I would add: do NOT cut the grass less than 2 - 3" tall, and use a mulching mower, to leave grass clippings as a natural fertilizer. Many times, additional fertilizer is not needed. I do NOT recommend most grub control. Just read the environmental & health warnings on the bags to see that they are not benign. For people who insist on controlling grubs, there are a few organic ways to do so. LOL, moles usually do an effective job. BTW, even if you eliminate all grubs, the moles will just begin eating earthworms, which happens to be their favorite treat. With fewer earthworms & their castes, you'll have to fertilize the lawn more. A rather vicious cycle is created when we mess with Mother Nature. I hope that the impression was not created that lawn services are the only reasons that infertile eggs occur. Two problems involved in "research" Likewise, we spray the yard, we notice no dead birds. We assume everything is fine and we continue to spray. However, we do not realize that this particular chemical does not kill the individual, it just causes their offspring to be sterile. So the next spring, our bluebird eggs are not hatching and we never associate it with something that happened the year before. Of course, this was just a hypothetical situation. However, scientists are discovering that certain species of frogs are living quite well, but can not reproduce because of earlier chemical exposures. Another example is research indicating that mothers taking DES were birthing daughters growing up to have cervical cancer. Pages can be filled with true accounts of how nature has gone awry in ways that we could have never predicted. So, getting back to bluebirds, always question why you believe that something is harmful or helpful. Sometimes cause & effect are not as straight forward as they seem. Dottie Roseboom From: Bruce Burdett [mailto:blueburd"at"tds.net] Sent: Wednesday, August 18, 2004 4:32 PM Subject: Re:Unhatched eggs and lawn fertilizer Dottie, Thorstein Veblen in his "Theory of the Leisure Class" has a great section about "lawns." It's priceless. He looks at the whole origin of "lawns," and of how they became popular. Originally, of course, they were simply fields kept short by grazing cattle or deer, but when Suburban Man ceased to keep cattle he tried to retain that chic grazed-over look. Now it's considered unfashionable to have more than one species of grass in one's "lawn." For my part, when I see a lush "lawn" of uniform color, I'm filled with something, but it certainly isn't envy. If I were king, "lawn care" companies would be made illegal. Bruce Burdett From: Lawrence Herbert [mailto:lherbert"at"4state.com] Sent: Wednesday, August 18, 2004 6:11 PM Subject: removing unhatched... What I do, and have always done, is: (most of you guessed) leave well enough alone and let nature take it's course. There is quite a bit of difference between monitoring and managing. Managing requires a permit....... From: Evelyn Cooper [mailto:emcooper"at"bayou.com] Sent: Thursday, August 19, 2004 8:13 AM Subject: RE: removing unhatched... What I do is help when I see a problem. The Wildlife people do cut us some slack when they know we are helping the birds. They have bent over backwards being nice to me about it. Nature did not put that little man made nestbox out there. Evelyn Cooper From: Lawrence Herbert [mailto:lherbert"at"4state.com] Evelyn makes an excellent point. Life is certainly not just black and white. It is also many shades of gray. (And brown and green and um... blue)! Good birding, Larry H. Joplin MO. From: Dottie Roseboom [mailto:rosedot"at"mtco.com] Bruce, it's too bad that we aren't neighbors - boy, wouldn't the "perfect" lawn people hate us! BTW, we have enough honeybees that visitors will comment on it. But the bumblebees (natives) are my favorites. I used to pull dandelions - until I saw the goldfinches ignoring their expensive Niger seed for the dandelion seeds. (I'm cheap too!). So now the only lawn weeds that I'm really aggressive against are Creeping Charlie & garlic mustard. These are very invasive plants - pretty much the house sparrow of the plant world. Riding lawnmowers are another pet-peeve of mine. (were you reading my mind?) Can't believe how many huge riding mowers I see being used where the entire lot is small enough to fit into my front yard. And then these people pay good money to join a gym. LOL Of course, maybe I'm a bit prejudice against lazy people, as my mother lives on an acre lot, which she mows with a self-propelled push mower. (finally, this summer, talked her into getting some occasional help) Grazing stock, huh? Llamas & alpacas have been on my Christmas wish list for years. Then, maybe I could get a picture to rival Wendell's: a silky alpaca surrounded by swallowtails, with a bluebird approaching the alpaca's neck. ;-) Dottie Roseboom Peoria IL (central - zone 5) From: Jody Jackson [mailto:jodyrn"at"bright.net] Dottie and Bruce, My lawn would match yours.... There is very little "grass" in our lawn - which covers 3 1/2 acres. Lots of dandelions in the spring. Lovely yellow color. ;-) There is a lot of clover (bunny rabbits coming and going all summer enjoying the feast). And just FYI, we have noticed a lot more honeybees this summer. There are several places where we see wild strawberries, but keeping it mowed they do not produce fruit. But there is a pretty little white flower. We never put any fertilizer or insecticide on it. As a matter of fact, I was very upset earlier this summer when there was a small plane spraying something on the corn field that surrounds all 3 sides of my property. I don't know if it was spraying for weeds or insects...Either way I didn't appreciate it much, but we didn't notice anything different afterwards. Our "grass" was not damaged, and I didn't notice any problems with the birds. So I guess I was needlessly upset?? But we are guilty of a "riding lawnmower". My husband has back and leg problems, and I work full time. He does the mowing which takes the better part of a day to do it all. Or mostly he does it in 2 days and it takes about 3-4 hours each day. We have many "bugs" living here in the lawn. The birds have a virtual feast out there... And I think putting lots of stuff on the lawn is waste of money. Unless you walk out through our yard, you would never know it was not just grass. And if we did spend a lot of money getting all the "non-grass" plants out and replant just grass seed....how long before the "non-grass" plants will be back?.... brought in by my friendly bird friends and the wind... LOVE IT IN THE COUNTRY!! Jodyrose
From: JCGARRIOTT"at"satx.rr.com [mailto:JCGARRIOTT"at"satx.rr.com] Sent: Thursday, May 05, 2005 10:15 AM Subject: Bluebirds re-nest One pair of EABL had completed a 5 egg nesting by April 7, mother incubated for 26 days with no results. Yesterday when I looked in I saw a nest with no eggs. On closer inspection it was a new nest begun on top of the "dud" clutch. I removed the lower portion with the 5 eggs to let them start with a lower nest level (hope that was right). From: Bet Zimmerman [mailto:ezdz"at"charter.net] My favorite website on candling eggs is http://www.homestead.com/shilala/candling.html because there are some really good pictures. Good job trapping the sparrows, clearly the bluebirds appreciated it. Weather here has been cold and rainy so there has been some delay in hatching, don’t know about your way. Sometimes the female doesn’t start incubating right away when weather is a factor. I assume you are counting the 12-14 typical days from the date the LAST egg was laid. I think I’d wait maybe 10-14 days after when they were expected to hatch before removing eggs, just in case. It’s still early in the season, so they’d probably try again. Bet from CT From: Laurel Baty [mailto:laurelbaty"at"comcast.net] Thanks for the candling link. I am counting from the day the last egg was laid and incubation began. Today is day 23 and she is still incubating the eggs. I don't know of any nearby bluebird boxes although I know there are bluebirds nesting in the area. We have had bluebirds nesting in our yard for 5 years and have never had an early failure of eggs although we almost always have one infertile egg per clutch. This has been a cold spring but nothing like some of the Messages that I have read from Michigan! From: Bryan Coffey [mailto:yeffoc_nayrb"at"yahoo.com] Sent: Thursday, May 12, 2005 10:53 PM Subject: bluebird nest removal I think my bluebird box is barren. The eggs have not hatched. The last egg was laid on 4/20. The night time temperature in East TN was in the low-to-mid 30's from 4/23 thru 4/25. The female continued to incubate up until yesterday (5/11). That was the last time I saw her. I haven't seen the her at all today (5/12). Should I wait a few more days to see what may happen? Please advise. Bryan Coffey From: Laurel Baty [mailto:laurelbaty"at"comcast.net] My female bluebird finally stopped incubating today--the 27th day of incubation. Male and female are interested in another box in my yard--of course it is my trap box for house sparrows (I have trapped 6 house sparrows there this year, 1 female yesterday). The male bluebird went in the new box and removed a stray piece of grass. The female bluebird has entered the new box several times but I have not seen her carry grass into the box. From: Tommy [mailto:tmathis840"at"comcast.net] My first clutch of 5 eggs failed due to the cold weather I'm assuming. The female built another nest on top of the old nest and laid 5 more eggs. They have now been in the nest for 20 days and not hatched yet. This seems strange to have 2 failed clutches. Mom and dad both are here and she is sitting regularly. Is it possible that he's sterile? From: Torrey [mailto:torrey_canyon"at"yahoo.com] Sent: Tuesday, May 24, 2005 10:16 PM Subject: Re: 2 failed clutches? It's more likely that a problem would be with the female. If she's accumulated toxins, those could be passed along in the egg yolk. Or it could be that they're genetically incompatible & the eggs develop a lethal something-or-other. The parents could have perfectly fine young with other partners. The chicks could be partially developed in both of these scenarios, so breaking an egg open (after you're sure it's not going to hatch) wouldn't tell you much. I've got an EABL nest right now where the eggs feel chalky. 2 of the 3 eggs are very light, like there's nothing in them. The pair doesn't seem to know the difference. I check that box again on Thursday (weather permitting, of course). Torrey Moss From: Bet Zimmerman [mailto:ezdz"at"charter.net] Sent: Wednesday, May 25, 2005 5:53 PM Subject: RE: 2 failed clutches? Couldn't the male be sterile? If the egg is partially developed, it means it WAS fertile, which I would think would be useful info, no? Bet from CT From: bookfanaticef-bluebird"at"yahoo.com [mailto:bookfanaticef-bluebird"at"yahoo.com] I suppose it is possible the male is infertile. Or if the weather has still been a bit cool, or rainy, or just a bit unusual, maybe they're being unusually slow to develop. Or she may have delayed the start of incubation for a few days--I've read they'll sometimes delay up to 2 weeks after the clutch is finished--especially if weather is bad. Even if you've seen her in/around the box, she may not have been incubating--I've had several boxes lately with birds flying out of them, or hanging out on top or in a nearby tree, and to my surprise, no eggs, not even any new nest material. But sometimes, birds are just unlucky. From: Tommy [mailto:tmathis840"at"comcast.net] The eggs are fully formed, although, in the first failed clutch, one of the Tommy Mathis From: Laurel Baty [mailto:laurelbaty"at"comcast.net] I posted news of the failure of the 1st clutch of bluebird eggs several weeks ago (5 eggs laid, 1 broken by HOSP, 4 eggs did not hatch after 28 day incubation). The Bluebird pair laid 5 eggs in a different box and 1 egg hatched today! Hopefully the other eggs will hatch as well. The female laid 4 eggs 16 days ago and I assumed incubation began when there were not 5 eggs on the next day. I checked the box 5 days later and there were 5 eggs--I do not know the date the fifth egg was laid. From: RBALTRUNAS"at"cs.com [mailto:RBALTRUNAS"at"cs.com] Hi I just checked my EABL pair. Here's the data 22 May one egg Those 4 eggs are about 22-25 days old. Looks like they are goners. What happened? Sterile eggs? They are solid and clean. Should I remove them or just let them be? Ron From: Autumn L. Kruer [mailto:autumnk"at"iglou.com] I was reading a PDF document from a person who has a bluebird trail who found eggs that hatched over 50 days old. I’m dead serious. He’s now concluded to leave what he once thought were sterile eggs alone. I wish I would saved that link. I found it when I was looking for premade predator guards the other night. Autumn in Kentucky Quote from October 14, 2003, FROM: Jim Cox, SUBJECT: Lake Forest Open Lands – Project Bluebird Recovery "The most interesting event of the nesting season occurred at this site. I recorded five new BB eggs at box #1 during a monitoring visit on May 16. A previous monitoring visit on May 9 recorded a slightly damp BB nest with no eggs. Thus, the eggs were most likely laid between May 10-15. I projected that egg hatching should have begun sometime during the May 26-30 time window. No further activity of any kind was noted during monitoring visits, which were conducted twice weekly. After one month of no activity, during which time no parents were ever seen, I curtailed monitor visits to two or three times per month. From May 16-31, all of June and a monitoring visit on July 4, all five eggs remained in the nest exactly as they had been observed on May 16. I was certain the eggs had been abandoned. I was considering cleaning the box out on my next monitoring visit, which was July 16. On July 16, I looked in the box and was astonished to see three healthy BB nestlings ~ 12 days old and two unhatched eggs. Working backwards, this meant the three nestlings hatched o/a July 5. This suggested an incubation period of at least 50 days occurred. It also suggests that a nest with intact eggs should never be considered abandoned during the active nesting period." From: Christy [mailto:ke4fej1"at"email.msn.com] Hi All, This year on our trails we had two nests that waited. One was over 30 days. I would not have thought this could happen, but I had read about 30 days not being unusual for a Mom to wait until setting, but that was for the northern BBs. But this year it was colder and I think our birds waiting until they decide to sit too. From: RBALTRUNAS"at"cs.com [mailto:RBALTRUNAS"at"cs.com] In a Message dated 6/18/2005 9:33:56 PM Pacific Daylight Time, autumnk"at"iglou.com writes: over 50 days old From: Trish Culpepper [mailto:trishkcully"at"earthlink.net] Trish - Frankston, TX From: RBALTRUNAS"at"cs.com [mailto:RBALTRUNAS"at"cs.com] Hi Trish, Comparing your situation to mine, You appear to have a few sterile eggs, too. but my guys have not removed any of the eggs so probably yours won't either. When they hopefully fledge this one nestling I have, I will have to clean out the nest and old eggs. A new clutch is probably better than the old eggs. I will also break open the old eggs. If they are just yokes then they were sterile. If developed then something else went wrong. Can't do anything about whatever the findings are. Just hope there is a next clutch and it does better. Tell me what eventually happens to yours. Ron Brooksville, FL From: Sharon Peregrine Johnson [mailto:sharonpj"at"swbell.net] Sent: Friday, June 24, 2005 10:27 AM Subject: Re: BB Question I have been moditoring my BB nest and one egg hatched on Tuesday. The baby was an pink/orangish color. However since then none of the other eggs have hatched and there are no visible cracks or puncture marks. Is it possible that the other eggs are sterile? The baby that I saw on Tues. morning is a darker color now. Anyway, I will keep checking. What are your thoughts? Is this normal? Sharon in Waco From: Trish Culpepper [mailto:trishkcully"at"earthlink.net] Sent: Friday, June 24, 2005 10:34 AM Subject: Re: BB Question 'Trish - Frankston, TX From: SCooke [mailto:ncw001"at"nc.rr.com] Sent: Tuesday, June 28, 2005 7:47 AM Subject: Re: Last of my BB's Jean et al, Sharon From: Jean Carter Wilson [mailto:peanut123"at"comcast.net] Sent: Wednesday, June 29, 2005 9:28 AM Subject: Re: Last of my BB's You know, I really have no idea. Mom is still incubating these eggs. Actually, I think it's only one of them that is spoiled...the other is as warm as the eggs out front and I suspect may hatch. So Mama will only have one little one, but that's better than no little ones. I've been running the sprinkler near her box as it has been so hot and humid outside. The female BB sits in the house with her face out of the hole, cooling off. She's so cute! I wonder if it's that these are first-time parents that don't know they have to move these eggs around every hour so they incubate evenly. Not that I'm going to go out there and do it for them, probably... Continued in Part 2 |
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