Monday, January 11, 2010

Bald Eagle, And My New Year’s Resolution

Yes, I know it’s January 11. So I’m late. But I’ve been busy lately, as I mentioned earlier, and I really do have a New Year’s Resolution. Ready? Here it is: I’m taking my camera everywhere I go.

Tangent: Oh. What’s that? I said I was doing a post on making martinis next? Yeah I put that off because a) blogging about this resolution will give me an excuse to tell about my cool wildlife sighting and b) I’m traveling for work most of the week, and that post will be the kind of mindless, zero-research filler post that’s easy to do from a hotel room.

As longtime readers know, I take my camera along while mountain-biking or skiing. But I don’t typically take it road-biking or running. You know, bulk, weight and all that.

Tangent: I take my phone (blackberry) biking, but not running. That may have to change. Most of my weekday runs take place at work, during my lunch-hour. Traditionally I’ve left the phone behind, figuring there was nothing so urgent it couldn’t wait <1 hour. But as my mileage has increased, and I’ve been out a bit longer, more and more often an urgent call or email will arrive during my run. In particular, over the past few months, my boss*, who resides 2,000 miles away, has taken to regularly calling with urgent matters during my runs.

*Oh, BTW, I have a new boss, who will provide material for a post I’m planning later this week. Yes, I’m going to blog about my boss. Because really, if you can’t blog about your boss, why blog at all?

Compounding the situation, the company that acquired my company last week appears to be staffed entirely by People Who Call Me With Urgent Matters While I Am Out On A Run. Seriously, I’ll go out for 45-50 minutes, and when I come back the blackberry is blinking so hard I need a potholder just to pick it up. So I think I’m going to start running with a phone.

IMG_3791 Lately I’ve been doing more and more trail-running, especially on Shoreline and related trails across from the zoo. Last Sunday afternoon I was wrapping up a trail run, popped out on Sunnyside, running West down the road the last ½ mile back to the house. As I was passing the zoo entrance, a bird flew, East-bound, low overhead. A big bird, with a profile I immediately recognized the profile as Eagle. I looked up as it passed expecting to see a Golden Eagle, when I caught a flash of white in the tail. It wasn’t a Golden; it was a Bald Eagle, Haliaeetus leucocephalus (pic below left, clearly not mine).

Tangent: Why didn’t anyone tell me trail-running was so much fun?* The foot-impact is softer, you use way more muscles, it doesn’t destroy your IT bands, and you see all kinds of cool stuff.

*Actually, someone did tell me: Rainbow-Spirit-Paul. He told me like 5 years ago, and I blew him off. Of course he was totally right. RSP is 5 years older than me, and predictably, he figures everything out 5 years earlier.

Bald_Eagle-Wingspan-1024x768There are over 60 species of Eagle in the world, but only 2 occur in the US. Though I see Goldens fairly often, in nearly 15 years of living in Utah, this was my first Bald sighting. It passed 20 feet overhead, ½ a mile from my house, and I didn’t have my camera. It passed low and slow overhead, like it might stop in a tree nearby. I pulled a 180 and started running East back up Sunnyside, following it.

The 2 American Eagles aren’t all that closely-related. Eagle phylogeny is confusing and in the process of (likely) being revised due to recent DNA studies. New and Old World Harpy Eagles for instance, turn out not to be all that closely-related after all, with some of their common features apparently having come about from evolutionary convergence, as opposed to ancestry. Snake Eagles appear to be more closely-related to Old World Vultures than any other eagles. Goldens are lumped into a group called True Eagles, which now appears to be a paraphyletic..

Side Note: Vultures, BTW, are a classic example of convergent evolution. Although they look quite alike, and have similar lifestyles, they’re not closely-related. black-vulture But how un-closely-related is unclear. For a long time the story was this: Old World Vultures, Aegypiinae, are related to Eagles and Hawks, while New World Vultures, Cathartidae, are more closely related to storks and herons. (I blogged about this last March when posting about Black Vultures (pic right, not mine either) down in Costa Rica.) But recent DNA studies suggest that New World Vultures are more closely-related to eagles and hawks than they are to storks and herons after all. Even if that’s the case, they still evolved their “vulture-ness” independently.

bald_eagleBut Balds (pic left. nope, still not mine) are part of a group called Sea Eagles- or sometimes Fish Eagles- for their common lifestyle of living near bodies of water- coasts, rivers, lakes- and feeding largely on fish. And it appears that Sea Eagles as a group are almost* monophyletic, meaning that they descended from a common ancestor. The closest relative of the Bald is the White-Tailed Eagle, H. albicilla (pic below, right), which lives a lifestyle much like that of the Bald clear across Eurasia.

*A couple species of Southeast Asian Fish Eagles are problematic.

WT Eagle They favor fish, usually nesting close to bodies of water, but they’re opportunistic eaters, feeding on everything from dead whales to rabbits to (surprising to me) raccoons and deer fawns. They’re strong, fast flyers, and live up to 30 years, becoming sexually mature at (usually) 5 years, when their head-feathers turn from brown to white*.

*When you think about it, the white head-feathers are the functional/signal equivalent of beards, breasts or pubic hair in humans.

Side Note: Raccoons and deer fawns are pretty big- bigger than a human infant. Have Bald- or any- Eagles ever preyed upon young humans? I poked around on this one a fair amount. Eagle attacks on humans certainly occur, but they appear to be mainly defensive- for example if the eagle perceives a threat to its nest. I couldn’t find any clear accounts of human children being preyed upon.

Giant_Haasts_eagle_attacking_New_Zealand_moa There’s a tale from the 1930’s of a 3 year old Norwegian girl snatched up by an eagle, and later rescued- unharmed- from a nest, but it’s almost certainly apocryphal. Maori legends tell of birds of prey large enough to snatch up children, and given the fairly recent* extinction of Haast’s Eagle, a 40 pound monster-sized eagle (check out the cool dramatization, left) which lived in New Zealand and elsewhere in Polynesia, the stories may have a basis in fact.

*~500 years ago.

The eagle landed in a tree at the East end of the zoo parking lot, paused for about 10 seconds, then flapped off across Wasatch Blvd, landing again in another tree at the West end of the recycling drop-off area at the corner of Wasatch and Sunnyside. I turned onto Wasatch, crossed the street and stopped and stared at it, as it perched, the perfect would-be photo subject, just 30 feet away. Oh, for my camera!

sighting route map For a long time I thought there weren’t any Balds in Utah. I’d never seen one, and many range maps show a curious hole above much of the Great Basin. But in last May’s Golden Eagle post (graphic right) a helpful commenter- let’s call her “Laurel”- mentioned having eagle snake meseen then in Springtime down my Old Mill, several miles to the South. Balds aren’t migrators in the classic North-South sense, but often migrate in Winter if the body of water by which they reside freezes over, and my guess is that this one was in the process of such a migration, looking for a spot to perch and rest for a bit.

Most everybody knows 2 things about Bald Eagles: that they’re the national symbol of the US, and that they were on the brink of extinction in the 1950’s and 60’s, due to loss of habitat, hunting and pesticides. Today they’re far more common, having been de-listed as an endangered species a couple years ago, but still at nowhere near their estimated population levels in pre-European-settlement times. They do best in Alaska, and though they range all over the West, still fail to nest successfully in much of California due to the lingering presence of DDT, which causes them to lay thin-walled eggs.

The Bald perched on a branch in a bare Cottonwood. The trees lining Sunnyside Avenue near the zoo are Magpie territory- you can almost always hear their calls when running or biking past in daylight. By the time I arrived at the Cottonwood, about a ½ dozen Magpies had alighted on nearby branches, and were squawking up a racket. As I watched, about every 20 to 30 seconds another Magpie flew into the area and perched on a nearby branch. Every once in a while one of the Magpies would get threateningly close, and the Bald would spread its wings and feint/lunge toward it to drive it back. I didn’t see any actual contact take place, but the Bald was getting little rest.

Mobbing Magpies regularly do this to birds of prey; ornithologists call it “mobbing.” Many other birds do it as well, and it serves (ideally) to drive off the raptor, but also to call attention to it and eliminate the possibility of surprise attack. Some researchers suspect mobbing behavior may even be a fitness indicator, with males showing off their genetic fitness (as potential mates) by daringly antagonizing a dangerous predator. Such fitness-related explanations for behaviors are hard to prove, but have been used to try to explain everything from stotting in gazelles to red leaves on Maples*

*In the leaf case, the Maple is not of course thought to be signaling in any way to other trees, but potentially to insect predators, advertising its fitness and presumed ability to ward off attack.

Tangent: Speaking of stotting, I got this nice video clip of a Mule Deer buck in front of my house over the weekend. I like it because it shows 3 different gaits in rapid succession- walk, trot, stott.

Mobbing is risky for both perpetrator and target. Gulls have been observed mobbing ospreys down into the water, where they’ve then drowned. Owls have been observed being mobbed by crows, and sitting still until finally lashing out and catching one who ventures too close, then flying off to consume their meal in peace.

The scene would have made an awesome video. And here I was- camera-less- just 1/2 a mile from home. You just can’t plan wildlife sightings; they either happen or they don’t. Time to start running with my camera.

I enjoy watching Magpies mob. With their alarm calls, their rushing to assist each other, and their daring taunts, it’s a IMG_3331great display of cooperation- and probably a fair amount of intelligence- in action. I felt a bit sorry for the eagle, tired, in a strange place, and seeking rest, but I identified with the Magpies. They reminded me of a gang of people, banding together to drive off a wolf or lion. Besides, I’m so used to the Magpies on Sunnyside, I kind of think of them as my neighbors.

And I wonder if they think the same of me. As we discussed in the Magpie post, they- and other corvids- appear to recognize individual humans. I run and bike by them so often, I’ll bet that they- with their superior eyesight- know and recognize me. Maybe home is where the corvids know you.

OK, seriously. Camera every run. This is a resolution worth sticking to.

10 comments:

nick said...

I was kicking myself last week for not hauling my camera around. I was visiting my parents and it was seriously the only time over a week that I didn't have some sort of camera with me. I was driving to the bank and stopped at a stop sign, looked to my right, and directly under the sign, like 10 feet away, was a huge red tailed hawk feasting on a fresh rabbit. I sat there for five minutes watching it eat, it was awesome, and I had no camera. So, good resolution, I think I'll copy it.

Christopher Taylor said...

Haast’s Eagle, a 40 pound monster-sized eagle... which lived in New Zealand and elsewhere in Polynesia

No, just in New Zealand. What's more, it may have lived only in the South Island of New Zealand - it's been suggested that the North Island forest may have been too dense for it.

Kori said...

I don't live in Utah, but when I was out there last year (on a business/ski trip), I was passing through Promontory and saw two bald eagles! The park rangers at Golden Spike said they are fairly common in that area.

Also, I decided some time ago that while it would be nice to have pictures of all the cool things that I see, sometimes it is just as good (or better) to simply enjoy whatever I'm looking at, and not stress about getting a decent picture. It usually looks better in my mind, anyway. But for you, I think it's a noble resolution, and will certainly benefit us readers.

ABranch said...

Bald eagles spend the winter months here. I usually see them around the Great salt Lake. An easy area to see Bald eagle action is at Farmington Bay where you can see 20-50 of them.

Here is a pretty good map for the bald eagle.
http://www.allaboutbirds.org/guide/Bald_Eagle/id

laurel said...

I feel very slightly famous as "Laurel." I have been seeing a great variety of hawks lately, one of which I cannot identify... It looked sort of like a Zone-tailed Hawk, but the white feathers on the underside of the wing were very white and the black outlining feathers were very black... not sure if you have any ideas...

WheelDancer said...

My brother used to tell stories about seeing Eagles in Alaska getting harassed by seagulls and every once in a while the Eagles would spin around and snap the head clean off one of the gulls at which point they all backed off for a while.

Cool video of the deer!

Watcher said...

Nick- yeah it’s always when you’re doing something that has nothing to do with wildlife that you get the best sightings…

Christopher- thanks for the correction!

Kori- I went through an anti-photo period, and always had a bit of disdain for travelers/observers who seemed more interested in photographing vs. seeing something. (I think it was the same period I always ran without an iPod, actually…) This blog has made me a photo-hound though, and it’s been nice having a library of photos I can go back and reference over the course of a year.

ABranch- I’m embarrassed to admit I’ve never been birding up at F Bay in the winter. Thanks for the tip, and have to change that.

Laurel- Hmm… maybe a Sharp-Shinned Hawk? They have a long, squared-off tail. Oh, I forgot- you qualify for a Watchersticker! Send a mailing address to adventureREMOVECAPSbotanist@yahoo.com

WheelDancer- Wow. That sounds cool.

Alex said...

We get bald and golden eagles wintering in Kane county where I'm from all the time. They eat lots of roadkill, but I've watched them take squirrels and jackrabbits off of ditch-banks.

Dingbat said...

I enjoy watching Magpies mob.
And they're such great flyers, too, just really graceful in the air.

Eric Wright said...

Stop it with the making me jealous of Utah already!