Bluebird Question

I have bluebirds nesting at my back deck in a nestbox under the eave near the corner of the house. They have returned from last year where their 3 eggs were apparently gotten by a snake. This year they successfully raised 6 young to fledge ( I got some great pics - eggtooth peircing eggs, etc), with 3 of the 6 returning after about 10 days in the trees to feed and learn about mealworms. I cleaned out the nestbox after they fledged (was that the right thing to do?) The dad wing waved, & enticed the female with new nest material, etc. The 2nd time, she laid 4 eggs. (1 of which was stolen by a carolina wren during some necessary roof repairs to my house and some very boistrous repairmen), but the other 3 are doing fine. I have a couple other questions.: Both parents fed the fledges normally until the very day before the new eggs hatched when they aggressively chased them away from both the mealworm dish and the 2 nearby roosting trees., until the poor fledges just left (I guess). Also I have provided extra mealworms to assist the single parent male in his duties. Recently I have read that mealworms depleat calcium and that if a large amount is offered to developing young they need to be coated with a mixture (I copied a supplement recipe) or at least an Avian vitamin drop formula to ensure strong bone formation. Does anyone out there have any experience or information about any of these issues? I hope to learn how to transfer pics from my dig camera to the computer, so I can share some of my recent shots . They are not anywhere nearly as fine as Dave's, but still worth a look. This is a great site and I feel very blessed to have discovered it. Thanks ahead of time for any info or insight you may be able to share with me.

Hi Birdie and Welcome to Daves and the Bird Watching forum!

I'll let Dave answer most of your questions but you were right to clean out the nestbox after they fledged. What happened to the Mama bird?

Looking forward to seeing your pics!

I think a Red Tailed Hawk ( seen occasionally in the area) or maybe a Kestral got her :-(
I am wondering also if, since it is primarily the male who selects & "owns" the nest site area, if he most likely will find another mate and continue returning to this site as he has now 2 years in a row? It is very cool to have them on my back deck. the nest box is great for a "cavity" dweller" but not your typical Bluebird nest box. Demensions are probably the same but the front ?third is open, rather than just an entry hole. I used to use these boxes for baby squirrels when I did wildlife rehabbing.

Welcome Birdie.

As Pelle said, our resident bluebird expert is "2dCousinDave." He has continuing bluebird threads with lots of information on his experiences. If you have time to go back and read his threads you'll discover wonderful information. For example, yes, he does clean out the box after the babies fledge, otherwise the birds will build a new nest on top of the old, making the young closer to the entrance. Pelletory has put his information on nestbox cleaning in the sticky.

http://davesgarden.com/community/forums/t/805666/

His male has ruled the box since 2004, and I think he is on his 3rd female at least since I've been around (1 year!!)

So Check it out! Here is the most recent. http://davesgarden.com/community/forums/t/865530/

Hi Birdie! Glad to have another bluebird afficienado to share with. Apparently, the male is loyal to the nesting box, as is the case with the blues at my site. New scenario at OP BlueBirds are Back.

Well, The 3 babies are now fledges! They left sometime yesterday (once again, I missed it!). We are having horid thunderstorms all this week, I pray they do OK..............Daddy was here this afternoon for a mouthfull of mealworms (which I am now dusting with Calcium powder).....also the mealworms that I set out this morning are gone. He must be feeding somebody! Yippee!! The hard part for me is being patient for a week or so till he brings 'em back around to feed "at home".

Birdie - I was going to suggest calcium powder. That's what I do for our geckos (lizards). We dust all the insects they eat. I think I'll start doing it, too. Can't hurt.

Have you ever seen the blue birds hanging out with American goldfinches? I thought it was just my imagination, but I'm pretty sure they are together a lot of the time.

OP --- You could very well be right about the goldfinches, as I noticed a couple in the bluebird's Dogwood tree (near the back deck). I call it their "lookout post".

I opened a Calcium - phos. capsule and just lightly dusted the mealworms. Since Daddy's returning for more I guess they're OK.
Please someone, let me know if this is a type contraindicated and what other would be best as there are a number kinds of Calcium available.

The calcium I use for the reptiles is 2:1 Calcium/phosphorus powdered with vitamins. I would check with a pet supply store.

thanks, OP, I will take my container and actually compare to the pet shop kind....often they are the same but greatly $ inflated @ pet shops (it's the retired nurse in me...always compairing ingredients)

OP --BTW, where is Orchard Park? I lived upstate in Ithica many years ago from age 61/2 - 9, with grandparents in Mount Vernon (near Queens, I think) I remember the summers and springs as lovely (though nothing like Sandiego where I had come from) This was in the mid 50's

I am still nearly bustin a gut to understand why the parents chased away (visciously) their own 3 fledges the day before the next clutch hatched. From what I've read it seems that "they would have no chance without some adult asssistance for about 100 days", so are they doomed to death. Might I ever see them again? I read in a BB book that frequently a 1st clutch will assist with the feeding of the 2nd. I am totally confused on this. Any input out there in wing waving land??

You probably won't see them again but they should be fine. The parents have to concentrate on the new clutch and the fledglings have to learn to be on their own. I think Dave said he's only ever had 1 insist upon staying to help with the new clutch.

OK, here are my 2 cents worth:

First of all, I don't think it is so unusual for bluebirds to chase the fledglings. It happens more often than not. For several years I have contributed to several exclusively bluebird forums and have heard most of my friends there complain that they had never seen a group of fledglings stay around after a subsequent nest was started. Despite what you may read, I believe it is probably more unusual for them to be allowed to stay. And to see a juvenile from an earlier clutch help with feeding the nestlings is VERY rare. I have seen it only once and have heard of it only a few other times. In the case I witnessed, the adult female did not appreciate it at all. In fact, as soon as she observed it, she actually positioned herself near the box and intercepted the fledgling each time he tried. That fledgling actually assisted two nestlings to fledge while the parents were away. A few days later that fledgling and his siblings were chased away.

In my view they will let them stay around longer if they stay out of the way. Bluebirds, especially female bluebirds, are very concerned about the location of the nest. They instinctively fly to distant locations to dispose of fecal sacs. When they take food, including mealworms to the nestlings, they (especially the female) often take circuitous routes and wait until the coast is clear before they actually fly to the box.

Fledglings, after they have learned to feed themselves, are left pretty much on their own. Like bored children, they often follow the parents around and peek in or perch on or near the nest box or on the sparrow spooker. This obviously makes the adults nervous, particularly if there is a HOSP presence. Incidentally, while the bluebirds may not like or even understand the phenomenon of the spooker, I believe the best chance of a HOSP losing its fear of a sparrow spooker is for the HOSP to see other birds on the nest box despite the spooker.

The other situation is where there is a change in one of the adults. In each case that I have witnessed this, it has led to chasing away the fledglings from the prior “marriage.”

And lastly, it would be too simplistic to say they cannot survive unless they have parental assistance untill they reach 100 days. We simply do not know enough about their behavior to say that. At 100 days they will look like the adults and more or less blend into the woodwork and become harder to track. I have seen fledges from a first nesting that came back later in the summer and they all apparently had survived. At least they came back in equal numbers. In the short run I think survival depends on the situation and terrain that they have around them. In other words, the availability of food and shelter. The greatest immediate danger is probably from predators, like hawks or even cats, while they continue to improve their hunting and flying skills. They are vulnerable since many insects are on the ground and in the open. There are lots of insects around until October or so. Food becomes a real problem in freezing weather when they must compete with many other species for berries or buds. But they are remarkably resourceful.

When we have a heavy snow (12 to 18 inches on the ground), I see 25 or more of them together, looking for food. And as many as four or five have been reported to huddle in a nest box to survive severe cold nights. But as soon as the situation improves, they again scatter.

Dave


This message was edited Jul 11, 2008 11:50 PM

Thankyou Dave! You must have been observing BB's for many years to be so knowledgable. I know that I speak for many when I say how much your input is appreciated.
I have a friend that tells me of a nestbox in her back yard that has many that stay in it together in the winter.

Birdie - Orchard Park is a suburb 10 miles south of Buffalo, NY.

Dave - I thought I remembered you suggesting putting up a spooker as soon as the first egg is laid. I did that today. What is your gut feeling about that knowing the history of this nest box? Should I leave it up? So far the hosp are leaving the bbs alone.

I would definitely leave it up. You have very little to lose. All you need is for one HOSP to fly into the area and spoil everything. If you read my diary in BB thread #10, you know I have a new female and that I am assuming she evicted the previous one. I found about 10 blue feathers in the grass under the nestbox. Of course, it is possible a hawk took her but considering the fact that I saw this new bird several days before and she was acting very aggressively and that she was immediately on the scene the day Mama disappeared, I feel she was the doer.

We were out of town for a funeral right after the new female showed up. When we left she had all but completed her nest but had not laid an egg yet. We got back two days later and found a large male HOSP in the nestbox, peeking out. When I went out on the deck, he flew away. When I looked into the nest box, I found it in shambles, nest material strewn everywhere. In that case I put the sparrow spooker up even though there was no eggs in the box. I also set the VanErt trap in the dummy box and caught him the next day.

Spooker or no spooker, there was an egg in the nest the following day. She only laid three and it makes me wonder if maybe there was one or more eggs in the nest while we were gone and if the HOSP destroyed them. I have never had a bird lay fewer than four before.

I was successful with the cage trap, and I will put it out again Monday. I have a VanErt on deck.