I am a bad blogger. I will readily admit that. I start the field season fresh and enthusiastic and fizzle out as the season progresses. I have a pretty good excuse: as I find more and more nests (about 100 each year the last 3 years) I get side-lined into my research and am too exhausted at the end of the day to sit down and write about all the cool things I saw. If I could clone myself, I'd be in business. But that's not happening.
So, once again, the bushtit breeding season looms and, once again, I am faced with the excitement of sharing the excitement----and the reality that I will do a pretty bad job of it. Ah well.
In this lull before my 2022 research in Portland and during my sojourn in the New England winter, I'd like to share a few highlights from last year's bushtit research that never made it into the blog.
The first is what was happening at Nest 28 and Nest 20 near the border between Sellwood Park and Oaks Bottom.
Nest 20 was in a monster pine tree on a very (very) steep slope. When we first found it, it was being built in the "lower" branches (30 or so feet up) in almost the exact location as nests in 2018 and 2019. Same branch. Same awkward position for watching. The builders this year were W-X -- a male who hatched nearby in 2019 and was rebanded as WUUX -- and an unbanded female. WUUX had been around in 2020, and we assumed he had a nest somewhere, but we never found it. His sister (also originally W-X) nested that year in a tree not far from her natal nest as well. (That throws a bit of a monkey-wrench into my assertion that females don't hang around, but disperse. I'll just ignore that for the moment...).
[BTW, both W-X female and WUUX were kids of PYLX who, if you've read some of the earlier posts, you may recognize as the second male at Nest 11 in 2018.]
A week after finding Nest 20 we found Nest 28 in a pine over-hanging a very steep slope just on the edge of Sellwood Park near the parking lot. It was almost finished and was being built by an unbanded male and a female (eventually banded as XYYY and XEEE). It was about 200 meters east of Nest 20. Not far. But not all that close either.
Neither nest was in a particularly favorable position for climbing up and banding the nestlings, so we put them both in a low priority category and watched them infrequently until.......
......very interesting stuff started to happen. On several watches (which later turned out to be during egg-laying when the female mates) WUUX showed up at Nest 28 chasing and following the female relentlessly while her male sort of fluttered around after them. WUUX even visited the nest several times...peering in and then taking off again after the female. This would go on for over an hour and seemed to be almost a daily occurrence for a week. WUUX was still seen at his own nest on and off, where that female was also laying eggs. (It certainly does beg the question: what was the female at Nest 20 doing while WUUX was off dallying with the female at Nest 28? Huh. Interesting. While the cat's away....??)
After a week of this foolishness, WUUX was back at Nest 20 behaving as a dutiful dad: sharing incubation duties with the female until the eggs hatched and they began to feed the nestlings. Which is when Male #2 (banded as RRRX) showed up and began to help. Because of the difficult position of the nest, we weren't quite sure when he arrived but by the time we did see him, he was merrily feeding as if he belonged there. And WUUX was perfectly fine with it.
Because of WUUX's frequent visits Nest 28, in particular, suddenly became a nest of great interest. Was it possible that the nestlings that eventually hatched were not just those of XYYY? Was it possible that WUUX has also managed to mate with XEEE and was therefore also a dad there? It seemed very possible. And now that it was possible, we needed to get to those kids and get blood samples for DNA as well as blood from both XEEE and XYYY. Remarkably, we already had WUUX's blood from when he was a nestling. I say remarkably because in most cases where there is an interloping male chasing a female at a nest, he is unbanded and we have no idea where he came from. And we never get his blood for paternity analysis. So this was a golden opportunity. We think we know what WUUX was trying to do. We know when he was trying to do it. And, most importantly, we know who he is and we have his blood already.
Perfect. As long as we can also get blood samples from the parents at Nest 28 and from the kids we would know if he had been successful.
But that nest.....Nest 28.......it was a challenge. It seemed a risky business to climb up to it. Nonetheless, we were determined. We dragged in a long, heavy ladder and found 2 limbs close enough together to lean it against at an awkward angle of maybe 20 degrees. I crawled up very cautiously and looped a rope around the branch the nest was on and pulled it carefully towards me. This is when a hanging, enclosed nest is a big help. No matter how much it swings or tilts, those kids can't fall out.
No problem. We got to the nest. But the kids were a few days too young. In the end we had to wrestle the ladder back down and up again twice before the nestlings were "ripe." Then it was a simple matter to band them and take blood samples.
That same day we successfully banded the kids two of us stayed behind and set up a net to get samples from mom and dad. This was also a bit of challenge because there was no good place to set up the net. My assistant finally sat under the net with tape of begging nestlings and the male magically hopped right into the net and we had him. Right before the nest fledged, we got samples from the female too. Eureka! A "complete set!" (says the vampire).
Now I also think it's very possible that RRRX was a father at Nest 20 along with WUUX, especially since WUUX was frequently absent and misbehaving at Nest 28. But we'll never know because that nest was truly impossible to reach. We did, however, get a blood sample from RRRX and hope to find out later if he is somehow related to WUUX. That's yet another possibility......that males who show up to help are helping close relatives.
We shall see....only the DNA holds that answer. Until then, the mystery remains a tantalizing mystery.
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