Buzz has been putting on quite a show for everyone, feverishly bringing in dozens if not hundreds of sizable sticks to the atrium of 185 Alewife Brook Parkway. You can see the old nest from 2010 & 2011 on the left (south) side of the atrium, and the new “nest” on what we called the “annex, opposite the old 185 nest. ” I've seen a number of people watching and photographing his intense activity, pursuing sticks from almost every tree within a hundred yards of 185. This morning he was landing on the short trees along the Whole Foods side of the overpass (Mt. Alewife) breaking branches off within several feet of passersby, many of whom were oblivious.

My impression is that this is not currently a “real” nest. Belle has not been seen playing any role in its construction. Rather, it seems as though Buzz is doing it to stimulate Belle to begin thinking about copulation and egg laying again. Just one week ago something happened to her clutch of eggs in the old Abt nest. Until then, she was likely ecstatic in that she had a new mate, probably her first nest since she was hatched, and her first clutch of eggs. (We don't know her history prior to roughly April 1, but can only speculate.) Everything was going wonderfully. Until..... She apparently lost her eggs and abandoned her nest. She still had her mate of roughly 6 weeks, but....

Buzz, however, has bred at least six times, and more likely ten to twelve times. He has mated with two different females this year. Copulated with each multiple times, and took turns incubating the eggs and feeding his mate. Buzz and Ruby, an experienced pair, began laying in early March in recent years. Breeding that early provides some cushion if a clutch fails. With Ruby's death while incubating, there was clearly still time for Buzz to find a new mate and attempt to copulate and lay with her. It took roughly three weeks for Belle, an unmated female, to be courted and fed rather lavishly so that physiologically she was primed for copulation and egg laying, which puts clear demands on the female. They copulated numerous times, primarily on the radio antenna where every Redtail within miles could see the new pair that had been formed. Those other female floaters who had responded to Buzz's “post on the Redtail dating/mating site,” could now see that he was taken. A new pair bond had been established. This helped Belle physiologically prepare for the stresses of forming and laying one to four eggs.

When Ruby had died, Buzz initially began working a bit on the old nest at 185 and putting up a rudimentary protonest on the annex. Belle had visited the old 185 nest several times and apparently did not care for it at all. They quickly stopped work on it and on the annex, and Buzz began carrying sticks from the annex to the old nest at Abt, where they built a new floor over the old nest bowl.

With the loss of the old Abt nest a week ago, Buzz feverishly began working, especially at dawn and dusk, on bringing in many sticks, often huge ones, to the annex at 185. It is possible that this could become a real nest, if Belle started working on it and bringing the feminine touch to it (Everyone who watched Buzz and Ruby build a nest knew that Buzz could bring the boxes from Ikea but he had NO friggin idea of where to put everything. Wherever Buzz put a stick, Ruby picked it up and put it where it really should go. Now that you see Buzz attempting to erect a nest by himself you understand why Ruby acted as she did.

I think the real purpose of this protonest is to serve as chocolate, racy lingerie, and fine wine to stimulate Belle's reproductive hormones, so that she will become receptive to copulation and egg formation again, just several weeks after she had completed that whole damn cycle. We have seen Buzz attempt to copulate (unsuccessfully) with Belle, and have one report where they may have actually copulated, but I doubt it. She just has not been receptive to Buzz's advances so far. That doesn't mean her hormones won't get flowing, but Buzz needs to do everything he can. The poor guy has been working up a real sweat before sunrise and working until sunset bringing in sticks. He often soars around 185 with the sticks in his beak or talon, so Belle can see him doing all this XCBZ for her! He lands on the roof of 185 with the stick in his beak, so she can see. He soars around the building and over the mall, stutter flapping, proclaiming his territory, all of which he claims and defends to maintain her in the style to which she wants to become accustomed. This protonest is part of his intense effort to get her to lay again. Buzz's instincts have to be telling him it is getting really, really late to breed successfully, and if they do not attempt again this year, an entire year will be lost. An entire precious year. Redtails don't have that many years. And 2013 was ultimately a complete failure as well.

If Belle is emotionally and physiologically primed to copulate again and begin laying eggs, time will be running very tight. It apparently takes two to more likely three weeks for this all to happen successfully, laying 2-3 eggs. Maybe Belle will be able to lay only one egg because of the stress her body has just been through, but data suggests it is possible for a female to lay at least two clutches in one spring. If she is primed, they will need a new nest and then they might have to work intensely on making the annex protonest a real nest. If Belle is not inclined to consider that a viable nest site, she may not even get primed for egg-laying. If she is committed to a tree nest, they will need 2-3 weeks work to build it. A major challenge, especially if Buzz has literally been busting his butt to build this protonest on 185. (And he has been working incredibly hard on it. We've not seen him hunting and feeding when he normally would be. Everything seems to be focused on getting this nest up and mating.)

This morning Belle was sitting on the antenna. In between stick deliveries to 185, Buzz would soar over to the antenna, do a display flight around it and land on a steel beam. But Buzz clearly never received any strong encouragement from his mate. No attempted copulation this morning that we saw. (Yesterday she had seemed receptive, bending over, so that Buzz glided in and landed on her back, but she dipped forward so that Buzz quickly slipped into dead air without any chance to fertilize an egg in development.)

As Buzz senses, time literally is running out. The likelihood is that is will be too late, that this protonest might never progress to occupancy. But we don't know for sure. It is likely that much of this story will be played out in front of our eyes and cameras in the next two weeks. Maybe even the next two months.

This morning an Asian woman was watching Buzz's activity while Susan Moses and I were watching as well. She called a friend, another woman who came over with old binoculars and her IPhone. They were both fascinated by what they saw. I learned that neither could speak English, but we both knew what they were thinking, especially as the second woman tried to photograph the activity through her binos with her cell phone.... We have the rare opportunity to observe Redtail drama in person, live, up close. No web cam necessary. A rare opportunity.

I've posted a bunch of photos of Buzz's nest building, of Belle, and of them together at my Flickr page.

Best,
Paul M. Roberts
Medford, MA
phawk254@comcast.net