When I last wrote, we were unclear whether we had really finished up with peak or if there was another push still upcoming. However, it soon became clear that our highest number days were very much over. Following peak, the raptor migration really died down in the Headlands, and the next couple weeks were bordering on tortuously slow. Then, just when I was beginning to worry that if the numbers were only going to get lower from here until December that I would have to start worrying for my sanity, the second Red-tailed Hawk peak soared in and saved the day.
At the GGRO, there are two different waves of Red-tailed Hawk activity. The first usually peaks around early September, and the second around early November. It appears that these are Red-tailed Hawks coming from two different source populations. The first peak is thought to be mostly local or nearby birds, while the second is made up of longer-distance migrants from the Great Basin and even farther north up into Alaska. (You can read the abstract about it in this paper written by members of the GGRO http://aoucospubs.org/doi/abs/10.1525/auk.2009.08120). You can even see the differences between the two populations visually—we are starting to see far more dark morph Red-tailed Hawks and Harlan’s Hawks than we did in the first peak. Dark morph birds happen relatively frequently among buteos and are essentially just a bird with very dark feathers.
On the other hand, Harlan’s Hawks are a genetically distinct subspecies of Red-tailed Hawks that breed in Alaska and the far north. They used to be classified as their own species and there are still a few raptor Biologists that argue they should be, but they breed in such remote locations it’s still a little difficult to know to what extent they interbreed with the other subspecies of Red-tailed Hawks. Rather than just looking like a normal Red-tail but darker, the whole color pallet of a Harlan’s is different. They are very black and white with an icy blue/gray eye rather than warmer-toned or brown with a chocolate eye, and they have a wide range of very different-looking tail patterns. They usually have pointed tail feathers and barring into the tips of their wing feathers. They can also come in both light and dark morphs, but even the light morph looks different from a normal Western Red-tailed Hawk. However, while other Banders and Hawkwatchers have encountered them this season, I have yet to actually see one in real life, so if you want to see what they look like, let Google do it’s magic (or look at this guide I found that’s pretty helpful https://www.aba.org/birding/v42n2p30.pdf).
Along with this second Red-tail peak, we are also getting a high diversity of birds in general. The main migration peak (in terms of highest raptors per hour) that we get at the GGRO is mostly made up of Sharp-shinned Hawks and Cooper’s Hawks, but there are 19 species that we typically see each season, some of which don’t even show up until that main peak is already long gone.
We’ve been seeing far more eagles (Bald and Golden) now, and we’re still looking out for the season’s first Rough-Legged Hawk. We call the latter “Pizza birds” because Allen Fish, our Director, buys pizza for the first team that sees it. It’s a nice goal to strive for when the overall numbers have gotten a bit lower. A week ago, there were three days in a row where Hawk Watch saw all four falcons: American Kestrel, Merlin, Peregrine Falcon, and Prairie Falcon. And although most of the accipiters pass by during peak, we have been seeing more adult accipiters now. The adult Sharp-shinned and Cooper’s Hawks are so striking, with brightly-colored eyes and bright orange breasts. So overall, things are still staying quite interesting out here.
One of the other things we talk about during the second Red-tail peak is that since these birds are migrating from farther away, it’s possible that they may be in poorer condition health-wise. They are also supposedly easier to catch, possibly because they are farther into their migration and therefore hungrier, or because they are better hunters and more likely to commit to a stoop (when a bird tucks its wings in and shoots down at its target) and get caught. However, we had a Red-tailed Hawk visit us in one of the banding blinds that I am shocked made it this far. We saw it fly towards us from far away, and it looked very committed to its stoop. However, rather than continue into the trap, it swooped down several feet away and began attacking something on the ground. We finally realized that it was holding onto the elastic string that connects to one of our traps, and attempting to eat it. It probably saw it move against the ground and thought that it was a snake. However, it didn’t just try to bite it, discover it was fake, and then leave; it spent over ten minutes attempting to kill and eat the string. Every time it would lift up one of its feet, the elastic would move the string slightly, and it would attempt to kill it again. It did this over and over and over again, until it finally got frustrated and flew off, completely ignoring the rest of the trapping site.
I got to watch Bridget, the outreach intern, give one of her final Hawk Talks of the season. Hawk Talks are one of GGRO’s biggest ways to inform the public about what we do. On weekends at Hawk Hill during September and October, someone from the GGRO does a talk (complete with wooden cut-outs of different birds) about what we do here. Then, if luck holds out, the talk is followed by a live hawk demonstration, where one of the banders brings a captured hawk up to the hill to release. It was really fun to watch Bridget engage a large, mixed-age group of people and effectively communicate some relatively complex ecological concepts. We were even lucky enough to have a cooperative female Cooper’s Hawk join us for the demo. There was a little boy there who was particularly interested in raptors (he called himself an “omniologist” aka someone who studies everything) and spent about an hour chatting with Bridget and me after the talk.
I am currently in the process of training to be a site-leader for Banding. Site-leaders are the people that run a banding blind; they assign tasks, assist other banders, designate luring strategies, make sure raptor health and safety is the number one priority, and decide what to do when things start getting busy or something goes wrong. It is a huge amount of responsibility, and studying for the certification process makes me feel like I’m back in school (sometimes in a good way). It’s really nice to have other banders supporting us as interns as we go through the process, and pushing us just enough that we learn a lot and start to trust ourselves in our jobs. It’s a good learning process because even as we take on more responsibilities, we are constantly relying on the experienced network of the other people with whom we work.