The Hawk Identification Challenge

The GGRO field research season is rapidly approaching. On August 19, the two major research projects (hawkwatch and banding) begin. We've asked the hawks to kindly wait until then to begin migrating. Most of them will cooperate, although a few strays may have missed the memo and might already be on their way south.

A red-tailed hawk hunting in front of the Golden Gate Bridge, a sight to become increasingly more common as migration season arrives.

Meanwhile, one of the main projects of the GGRO interns (aka me) is to "learn." We're learning how to care for lurebirds. We're learning how to set up dho-gaza's, bow-nets, and mist nets for trapping hawks. We're learning how to age buteo hawks based on their molting pattern. We're learning how to fill big holes with rocks. And we're learning how to identify all 19 of the common migratory raptor species, and all of their respective morphs, in flight.

Identifying hawks in flight is a tricky ordeal, but thanks to the fact that a lot of people have been doing it for a long time, there are some tried and true techniques. Through weekly evening ID classes, powerpoint study sessions with each other, and the occasional birding field trip, I feel like I'm slowly gaining confidence in my ability to identify a passing raptor.

It's a daunting ordeal at first - in sum, there are 68 different morphs that we could essentially see (juveniles often look very different from adults in a given species, and some species of dark morphs, light morphs, in between morphs, etc). In the classroom, we focus on learning field marks - what the hawks look like. Words like petagial marks, carpal patches, undersides, uppersides, mottling, barring, and streaking are thrown around a lot.

These are all different morphs of red-tailed hawks.

In the field, however, we get a chance to focus on something birders have termed the GISS: the general impression, size, and shape. In other words, many birders feel that field marks can only get you so far. Once you're in the field, you're going to learn a lot more information by becoming familiar with the relative size, the relative shape, and the typical behavior of a given bird. Last week, we went birding with Steve, a long-time GGRO volunteer who can tell the difference between a juvenile and adult red-tail hawk from miles away, based only on the silhouette.

I'm learning to identify birds like these with no hesitation.

We can study field marks until our brains explode, but once we get outside, that can only give us so much information. The confidence in identification will come from practice in the field. One more week until I'll be putting my hawkwatching skills to the test. Bring on the migration!