The Glamorous, Fabulous Ferruginous Hawk

(I'm no longer in California. I'll try to get my last few CA-themed blog posts written in the next couple of weeks before moving on to my next adventures!)

This is an article I wrote for the Golden Gate Parks Conservancy February 2014 e-ventures newsletter. It is currently published here:  http://www.parksconservancy.org/about/newsletters/park-e-ventures/2014/02-ggro.html

“Boy, I’d love to see a ferrug right now!”

This is one of the most often spoken statements by hawkwatchers at the Golden Gate Raptor Observatory, and understandably so. Large and majestic-looking, the Ferruginous Hawk (known as the “ferrug” in hawkwatcher short-hand) is arguably one of the most beautiful raptors we see at the GGRO. Adding to its desirability, Ferruginous Hawks are spotted from Hawk Hill no more than 20 times in a given year.

The Ferruginous Hawk is so named for the rusty-brown color infused on adults’ heads, backs, and upperwings. In the world of chemistry, rust is oxidized iron, known in the olden days as ferrous oxide. Add a couple letters and “ferrous” become “ferruginous.” The hawk’s scientific name also indicates its glamorous, physical appearance: Buteo regalis, which literally translates from Latin to mean “royal soaring-hawk.”

Often confused for an eagle because of its size, the Ferruginous Hawk is the largest North American buteo, the genus of hawks that includes Red-tailed Hawks, Red-shouldered Hawks, and Broad-winged Hawks. Identified by its characteristic long, tapered wings, large head, and robust chest, the Ferruginous Hawk is only one of three North American diurnal raptors to have legs feathered all the way to the toes (in addition to Rough-legged Hawks and Golden Eagles). In adults, these leg feathers are rusty-brown, forming a characteristic “V” shape that stands out when seen in flight. The chest of the Ferruginous Hawk is usually pale white, while the underwings of adults will have various amounts of rust-colored markings (brown in juveniles). 

Perhaps the most striking feature of these hawks, however, is the tail. In flight, the underside of the adult tail looks completely white, sometimes with light barring or some rust-color shining through towards the tip. Juveniles often show two to three gray bands towards the tip on the otherwise white tail.

During my first visit to Point Reyes National Seashore, I spent almost an hour watching a juvenile Ferruginous Hawk hunting over the grasslands. Using its long wings and tail to still in the air and moving its head back and forth, the hawk actively searched for jackrabbits and ground squirrels. Occasionally, it would stoop down and fly low over the ground before returning to its height to continue looking for prey. Cooperative hunting has also been reported in Ferruginous Hawks, where a male and female work together to catch prey.

For the motivated hawkwatchers, there are a few great places in the Bay Area to see Ferruginous Hawks overwintering. In Point Reyes, Pierce Point Road and the trail to Abbott’s Lagoon are surrounded by grassland habitat, ideal for seeing Ferruginous Hawks. Other areas worth checking out include Livermore Valley in Alameda County, Chileno Valley on the Marin-Sonoma County borderlands, and the southern extension of Chalome Valley between highway 41 and Bitterwater Road. The best time of year to look for Ferruginous Hawks in these areas is between December and February.

Seeing a Ferruginous Hawk from Hawk Hill is quite a treat. Although a sighting is rare, it is clear why hawkwatchers consistently consider this elusive bird to be truly glamorous!

(Thanks to Allen Fish, Bob Power, and Tim Behr for tips on where to find wintering Ferruginous Hawks!)

Road Trapping

Yesterday, I got a chance to experience "road trapping," which involves taking our raptor banding show on the road. Essentially, we drove around until we spotted a raptor. We chucked a trap out of the window of the car, waited for a few minutes to see if we could catch the bird, and then banded it right out of the trunk of the car.

Emma and Buzz band an American kestrel. All the banding materials are in the back of the car.

We spent the entire day driving around the Davis, CA, area. However, time flew by as we were constantly stopping and occasionally banding some incredible birds. Three of the six birds we banded yesterday were American kestrels, the charismatic little falcons that I have come to love this year.

Adult, female American kestrel.

Female American kestrels are aged by the final black bar on their tails. In this case, it was an adult bird because the last black bar is so much thicker than the other bars.

We were not successful in catching every bird we set the traps out for. Even so, just getting a chance to see some of these unique raptors was worth the trip.

An adult ferruginous hawk (the first adult I've ever seen). This bird is the definition of majestic.

Dark-morph adult red-tailed hawk.

The highlight of the day, however, was banding three adult red-shouldered hawks. There is a theory the other GGRO interns have developed that any black-and-white bird (especially if there is a hint of red) will automatically qualify as one of my favorites. Recent examples include pigeon guillemots, black phoebes, and California condors. Thus, these beautiful birds immediately won me over. So much so that I am writing in an uncharacteristically gushy way about them. But I'm putting science aside for this entry, because these birds are just plain amazing. See for yourself:

Red-shoulder #1.

Look at the black and the red and the white. Just look at it! Wow!

I demonstrate why this bird is called "red shouldered."

Are you seeing this bird? It's so cool!

Close-up of the feathers. Amazing.

Red-shoulder #2 was much redder on the body. Do you see this bird? Do you see how beautiful it is?

This is another shot of a red-shoulder looking incredible.

Red-shoulder #2 release shot.

This is red-shoulder #3, caught about 27.3 seconds after red-shoulder #2.

Some red-shoulders have particularly prominent hackles (feathers on the back of the skull), giving them a spiky-headed appearance.

So, here's the deal. I like birds (obviously). That being said, I like to think of myself as a scientist, biologist, what-have-you-ist. I like to take an objective perspective of my work and not resort to constant "ohhhhhhhh those birdies are soooooo cuuute!!" gushiness. That's not why I'm motivated to do what I do. However, I think it is important to take a step back every now and then and acknowledge the simple fact that these creatures are amazing, beautiful, incredible. Yesterday was an experience in research, but more importantly, in was an experience in awe-stricken appreciation.

Kiting

Ask most anyone to name some different families of raptors, and the list will usually include hawks, falcons, eagles, osprey, and sometimes even owls. It is rare, however, for someone to mention kites, at least in their first breath. The large, soaring buteos, the swift, agile falcons, and the majestic, charismatic eagles seem to be much more prevalent on our raptor-radars. It is a shame that kites are often absent from these lists, as they are unique and impressive raptors in their own right.

There are five species of kite that can be seen in North America. The one that has become familiar to me during my time in California is the white-tailed kite. Falcon-shaped with flight resembling that of a gull, the most prominent feature of this kite is probably its black shoulder patches. This inspired ornithologists to change the bird's name to "black-shouldered kite" during a brief identity crisis in the '80's.

An adult white-tailed kite is a striking sight to behold; in addition to the black shoulder patches, distinctive black carpal patches can be seen on the underside of the wing. The head, body, and tail are completely white, and the underwing becomes progressively dark moving closer to the tips of the primaries. The adult's eyes, surrounded by a patch of black, are a deep scarlet. Juveniles look similar, but with rufous-colored feathers along the breast, a narrow band towards the tip of the tail, and a brown-colored eye.

(photo: www.wikipedia.org/)

During a birding field trip to Skaggs Island yesterday, white-tailed kites were one of the most frequently spotted species of the day. Across the landscape, I spied multiple kites, perched in the bushes or displaying my favorite raptor behavior: kiting. In this hunting strategy, which just so happens to be the origin of their namesake, white-tailed kites hover in place over the landscape, flapping their wings in a way that is necessary to hold them and place and captivating for the hawkwatcher. The kites will continue to do this behavior until they see a rodent (which they prey on almost exclusively) and stoop down to strike or move on to investigate a different area.

When kiting, white-tailed kites look almost angelic in appearance.

Kite populations were declining rapidly at the start of the 20th century due to hunting and egg collection practices; white-tailed kites were all but extinct in California by 1940. However, thanks to protective legislation and the abundance of prey available to them at agricultural sites, their populations have rebounded since this time. Even so, there are rapid fluctuations in white-tailed kite population numbers from year to year due to similar fluctuations in prey availability. This makes it challenging to collect accurate censuses, and many ornithologists believe that we should still be watching white-tailed kites closely for signs of sudden, significant decline.

While white-tailed kites and all their kite cousins may not be the poster children of the raptor world, they are equally impressive and ecologically-essential. This is one bird I am going to miss seeing on a regular basis when I leave California and I believe it deserves equal time in the spotlight as its more-famous raptorial counterparts.