Friday, November 19, 2010
Returning falcons confound and excite the island's bird detectives
They're back.
Or at least we think they're our falcons from last winter.
Long story short, in late November 2009, I spotted a lightly colored bird standing straight up atop one of Alcatraz's tall cypress trees. It was far away, but its vertical silhouette seemed very out of the ordinary. I pointed it out to Ranger John and asked him to identify it. He nailed it on the first try. It was a peregrine falcon.
The bird, which turned out to be a female, was then joined by a juvenile male. The two remained loosely allied throughout a winter of fun and brutality, feasting on European starlings and unwary seabirds. In their spare time, they provided drama for the usual bird bosses of Alcatraz, our very large and extremely territorial pair of common ravens.
One day in March, our female enjoyed one last meal on the top of the power plant's smokestack, spread her wings like sails into the wind and left us for the summer, presumably to breed with a sexually mature male in a territory somewhere to the north.
The male was last seen at June's closing. Before that, his relationship with Alcatraz seemed more and more tenuous... some experts judged that he was holding Alcatraz as a future breeding territory. The possibility was exciting, especially for those of us who had first participated in discovering and observing him. Alcatraz has never hosted breeding peregrines before. Given the summer population of 1,500 to 2,000 large and aggressive gulls, no one was even sure that breeding peregrines were a possibility. To our dismay, the frequency of peregrine observation was declining, finally approaching zero.
And then...
Last Sunday, October 9th, I saw a male peregrine falcon with mixed blue and brown plumage on the Alcatraz lighthouse, in the exact same spot that I'd seen our male all of last winter, and indeed, at the same time in the early evening. His prime viewing hours are 5-7 pm.
The blue and brown feathers indicate that the peregrine is in transition. He's shedding its brown juvenile quills and donning the prim and chivalrous blue coat of a breeding adult warrior.
The very next day, still stoked from the rediscovery of our male falcon, I made another find: an adult female falcon in the very same cypress tree that our female falcon from last winter preferred. For me, as a birder of The Rock, this was a huge personal lift. BourbonHawk and I have spent countless hours stalking and observing this falcon, neurotically checking her perches even when she had been absent for months. She is the raison d'etre of this bird blog.
But is it the same falcon pair from last winter?
As it turns out, falcons don't wear name tags. Hell, falcons not obsessively stalked by unstable birders don't even have names. Confirmation that the falcon you saw today is the same bird you saw several months ago isn't easy to produce and in the male's case, there may be reason to doubt his identity as our heroic but moody tiercel from the winter of 2009 and 2010.
His age, given away by his plumage, is a perfect fit. His blue and brown feathers firmly indicate that he hatched in the summer breeding season of 2009, just as our falcon did. He sits on the same east facing ledge of the Alcatraz lighthouse at the very same time of day. He looks to be about the same size.
None the less, we can't be sure that he's ours. In June, we saw another male falcon undergoing the same transition from brown to blue. If the two had been the same bird, it sure seems as though the molt would be complete by now. As it stands, we can't rule out the possibility that we've been mistaking two male falcon yearlings for just one.
On the other hand, artifacts of digital photography and bad early evening light in a fog ridden context could also be distorting our sense for his coloration.
One raptor expert told us that the preference of two similar falcons for the same roost might be explained by the attraction that they have for the aggregated guano of other falcons.
None the less, my intuition that this is our same falcon is bolstered by the fact that since May, Alcatraz has had a brown falcon sporting one or two blue feathers. With every observation of a falcon in transitional plumage as the year went on, the blue went up and the brown went down. Call me crazy but I think it's the same bird, even if it's taken several months and our intuition is that the whole blue to brown molt should happen inside of 30 days. (Important to keep in mind: every time I assert a suspicion without concrete evidence, I seem to be wrong. Example: the time I wrote about a thousand words on how the raven pair was deceiving the National Park Service and incubating a nearly unprecedented second clutch of eggs)
The identity of the female seems less mysterious.
Unlike at the lighthouse, her cypress tree doesn't have aggregated guano on it, and she hangs out in each of its boughs and branches without regard for the presence of peregrine droppings. Call it a subjective unscientific judgement, but she seems comfortable and very much at home in this tree.
Watch out, ravens...
The presence of a pair of adult peregrines on Alcatraz should strike fear into the heart of the island's ruling pair of majestic corvids.
The relationships between ravens and raptors are varied, complicated and potentially violent.
There are recorded instances of ravens killing falcons and falcons have certainly put an end to many a proud raven. Falcons, transcending their smaller size, have even killed golden eagles, some of the most fearsome raptors the world has to offer. The warlike behavior of our young male last winter, attacking any bird of any size from large gull to large raven, gives me every assurance that he is an aggressive creature that fears nothing but a lack of suitable targets.
On the other hand, there is also evidence that ravens and raptors can live in cooperation with one another, especially after a period of years in close proximity. The raven and raptor pairs come to accept the presence of the other and there is even some evidence that they share defensive duties and come to understand one another's alarm calls in the case of an unwanted invader.
In peregrine falcons and common ravens, you have two of the smartest and most complicated minds in the avian world. Concrete expectations for how the two pairs might interact are bound to be a source of frustration and disappointment. Still, up to this point, it's been all fistacuffs, and I doubt the ravens are happy to see our falcons return.
Coming soon:
-How the female falcon is a product of the sexual revolution (hint, she has a boy and a house for the summer and another boy and another house for the winter.)
-How long has Alcatraz had seasonally resident falcons? There's reason to believe that it's longer than we think.
Lastly:
There are those that take our aforementioned ravens to be "nasty birds", worthy of little more than target practice for our capable and burly law enforcement rangers.
I would make the case that while they are carrion and trash eating voracious predators, they are also the most committed couple the island has to offer.
The other day, BourbonHawk remarked on just how odd it is that we never see our ravens eating carrion... then we saw this:
Yes, that is the foot of a tiny dead bird, attached to its downy fluff.
They'll even eat the cutest baby gull if it pleases them...
Nasty? Perhaps, but unlike our sexually liberated falcon femme, these two stay together at all times during the year, abiding by each other, feeding, preening and keeping each other company. Falcons should be wary because these ravens will certainly protect each other.
Wednesday, November 17, 2010
Following BourbonHawk: Birding Away From The Rock
I'll pen another sarcasm laden post soon. Tonight, we're all business.
America's National Park System is an entity with so infinitely many virtues that if you began to list them, you'd just never finish.
The genesis of Golden Gate National Recreation Area, of which Alcatraz is just one facet, came partly through the enlightenment of Congressman Phillip Burton, representing at times, California's fifth and sixth congressional districts.
cool tie, also digging the haircut and those unmatchy pantsHe only concerned himself with the fate of public lands when it was explained to him that rich folks have their own lakes, their own yachts, their own snazzy houses on the shores of said lakes.
Shouldn't everyone else at least have the pleasure of walking along the shore of a lake? I mean, at the very least? For Burton, that was all it took.
By the way, it was his strategizing and haranguing that gave Alcatraz to GGNRA. If our urban park has a founding father, well... But enough about him for now.
As awesome as the Golden Gate National Recreation Area is, it's not the only name in the public land conservation game.
Adventuring off the reservation
Out of the park
Out of the National Park System
Out of the park
Out of the National Park System
I love BourbonHawk's idea of covering bird life throughout the GGNRA. In the spirit of that temporary journey away from Alcatraz, here's a trip even further afield.
Last weekend, my father and I hiked Rush Ranch, a piece of land on the Suisun Marsh, waaaay over there in Fairfield. It's maintained by a nonprofit called the Solano Land Trust and to be sure, we had a fantastic time. There were raptors everywhere:
white tailed kite
prairie falcon
red tailed hawk
golden eagle
Seeing all of the hunting sites around Rush Ranch also gave me pause. I'm a huge animal lover and a strict vegan. I've been a vegetarian since I was around 10 or 11, if I remember correctly and I can still remember my last box of Burger King's chicken tenders which had satisfied me so reliably.
I've been a very good liberal about hating guns and hunting, thinking it cruel and unnecessary, not quite seeing the point.
On reflection, however, I think going out and dispatching your own meat is far better than getting it from the factory farm. These hunted birds live their wild lives, enjoy their natural diet in the comfort of a habitat protected from human encroachment. Those that do fall at the guns of hunters may experience brief periods of suffering prior to their deaths, but animals in factory farms endure pain and mistreatment throughout their entire lives.
Sure, if you're a duck, it sucks to be shot. But there are innumerable hawks, eagles and falcons to remind us that when you're a plant eating marsh bird, mortality is part of the equation and every single one of these raptors has to find, attack, kill and eat an animal every single day.
Hunting also seems far more environmentally friendly and sustainable than factory farming. Factory farming is not inextricably tied up in the business of conservation. Hunting absolutely is.
Though I would never, ever, ever go on a hunting trip or kill any animal bigger than a spider, it does at least seem to be a nice day outside with the family, in a country where people spend far too much time in front of screens like this one.
Finally, from my dear father's collection, you can get an even better sense for the ecological richness of this place. You see, he's a better photographer and he's got a snazzier camera. I can promise you an extra cool picture of a red tailed hawk diving on a juvenile golden eagle. So rad.
Next time: back to Alcatraz.
Monday, November 15, 2010
A new facial disc in the wings, claws and death game
Bonus shot:
After a one on two fistacuffs with the island's raven pair, our female peregrine kicks back on the smokestack, faces west and relaxes in the setting sun
But this post isn't about her. Onto the true substance of it...
What an odd moment that was. On Thursday, October 28th, BourbonHawk and I trekked up the long and winding path from the dock to the cell house which crowns the peak of the island. As we rounded the final switchback, we spooked a bird from its roost in the dark boughs of a pine tree.
She was light in coloration and at first she seemed to be about the size of a gull, so I just assumed that's what she was. As I took a casual second glance, her plumage took on a rusty color that made me think we'd spooked a visiting hawk. How exciting!
But no. As I watched it slide slowly and gracefully through the air, it's shape was that of a zeppelin, a reddish-white football with rounded wings beating quite casually. It had no neck, and its head, or at least its face seemed to be made up of a forward facing disc. It's proportionally immense feet, toes and talons were carried below and behind in tow. Wow. That was a female barn owl!
As she glided past the ravens' tree, I imagined the two dark corvids perched together on a dark bough, looking on and cursing to one another about the sudden arrival of still another avian apex predator, "Damn... first a pair of falcons that dive on you with their claws out faster than any animal that has ever lived, and now a huge bird with a full f#$*%ing swiveling and serrated cutlery set instead of toenails? And what's with the lack of a neck to conveniently claw and chew on! Weak all around!"
BourbonHawk and I found ourselves off work for the next two days, but we returned to Alcatraz on the 31st. On that night, which conveniently happened to be Halloween, we'd just closed up shop on Alcatraz's acclaimed night program when a creaking and eerie screech permeated the darkness around us. It quickly became loud enough for us to spot the cuprits, a pair of ghostly white barn owls floating and fluttering around one another like loud, etherial butterflies spinning circles around a candle's flame.
A pair of barn owls on Alcatraz! What an awesome find!
Sorry for the lack of owl pictures. The owls may love the pitch black but my Canon SX10IS just doesn't. Hopefully these new peregrine pics console you a bit, at least until I find a sleeping owl in daylight. Here's hoping...
MAGANRORD quick hits:
The male peregrine hasn't been seen in weeks but he's got a weird way of being absent for long periods of time and returning just when we've given up on him. So I'm still checking for the little guy.
Laura, our radical wildlife biologist saw a merlin on Alcatraz. We're pretty jealous.
The female peregrine shows off her own cutlery
Saturday, October 16, 2010
A New Feature: Birding around the GGNRA
As many of you are aware of, Alcatraz is part of a larger national park known as the Golden Gate National Recreation Area. This park is a group of sites maintained by the National Park Service around the San Francisco Bay Area and constitutes one of the largest urban parks in the world.
While we certainly intend to keep the focus of this blog on Alcatraz and the birds we find there, there is a really great amount of bird life to be found in our other park sites as well. Having spent a little while at Crissy Field yesterday, I figured I'd kick off this installation with a few shots from yesterday and from the past that I've taken there.
Long Billed Curlew
Killdeer
Great Egret
Great Egret
Black Bellied Plover
Ring Billed Gull
Cormorants, Gull, and Brown Pelicans
The nicest thing about a site like Crissy Field is that it's very easy to see all sorts of bird life without having to trek far, break out the binoculars, etc. It's right there in front of you. In hanging out there for about half an hour yesterday I saw the following birds:
1. Red Tailed Hawk
2. Red Shouldered Hawk
3. Brandt's Cormorant
4. Double Crested Cormorant
5. Brown Pelican
6. Western Gull
7. Ring Billed Gull
8. Snowy Egret
9. Great Egret
10. Black Bellied Plover
11. Unknown Species of tiny, tiny Plover
12. Unknown Species of medium-sized Sandpiper
13. Killdeer
14. American Coot
15. Unknown species of Tern
16. Crow
17. Common Raven
18. Black Crowned Night Heron
19. Mallard
20. Tons of little tiny songbirds that I have no idea about
This also makes it a great site for the beginner or the casual birder, which I still sort of feel like I would be categorized as, not having a huge amount of field experience other than what I see on hikes or out there on the island.
Wednesday, September 29, 2010
The imminent relaunch of MAGANRORD!
But we're about to get back at it. There's just too much more to say about the breathtaking ecological richness of our little island.
So here's what's happening: In the next day or two, our graphics will be back up. BourbonHawk has hooked it up with a mighty fine hosting solution. For my part, I will produce content of a higher quality.
My more recent posts just haven't measured up to the standards I have for my own writing. I read them and I yawn. For some time, it's seemed to me that the deeper you dig into the Maganrord archives, the better the posts become. Now, I'm back and I'm going to reverse that trend.
For now, I'll leave you with a few heretofore unpublished pictures from one of my favorite adventures with BourbonHawk, our trip through the abandoned brandt's cormorant colony.
BourbonHawk's original post can be found here. Check it out. It's awesome.
Monday, August 30, 2010
Scattered birds of prey sightings and the changing of the season...
The doldrums...
There hasn't been much news to report, but that's typical of this time of year.
The trials of nesting season are largely behind us. The gnashing of bloody bills in combat to the death, the infanticide against your neighbor's young, the desperate pursuit of a morsel of food that might help to sustain your brood of one to three needy young furries, the solemn necessity of bloodying a newly airworthy young gull that accidentally flies into your breeding territory... it's all largely over and it's given way to this:
Quietude. I wonder if the gulls have the capacity or the inclination to sigh in relief. Perhaps they know that a respite like this lasts only until next spring. Then, we'll live the horror again.
Personally, I wonder if these birds find themselves relieved that they can again indulge in a diet of discarded chicken and other trash.
Who could know?
Birds of prey spotted on Alcatraz
When a red tailed hawk has occasion to visit us on Alcatraz, the gulls, occasionally with a bit of help from the ravens, give the invader the boot. One recent example:
And this is what it does to the gull colony:
They go crazy. While I've heard rumors that red tailed hawks have had their way with a juvenile gull here or there, my experience in the six or so hawk invasions I've seen over the last two and a half years is that the hawks are harassed and pestered by several hundred gulls until they simply leave with nothing.
Why the ravens choose to get involved seems mysterious at first, but they engage with the invaders to ensure that birds of prey don't take advantage of the ample food resources that avail themselves on the ravens' island. Our two ravens preside over a large seabird colony equipped with thousands of large gulls ready to repel any visitor sporting broad wings and a sharply hooked bill.
These ravens are quite serious about protecting what's theirs. Our apex predators will do all they can to ensure that any winged animal adapted for killing finds its way off the island.
BourbonHawk and I recently witnessed an example of this first hand:
An unidentified juvenile hawk perched on a fence outside the entrance to the Alcatraz cellhouse. One of the National Park Service's fabulous bird interns helped us to conclude that it was probably a red shouldered hawk.
Just as soon as the young raptor arrived, one of our large ravens landed next to it and began to examine it up and down, quizzically, as if to ask, "youngster, just what are you doing here?"
Well, after just a few seconds of physical or social discomfort, the young hawk flew off to the north side of the island, causing a terrified cacophony among the gulls there. C'mon gulls! It's just an immature red tail; grow a pair!
Lastly, on the raptor note, falcons have sadly not been seen since our last post.
The year of the California gull comes to a close:
Earlier in the year, we could reliably expect to make constant visual and auditory contact with these holy-to-Mormons gulls on every outing. Now, we don't see them much at all.
Breeding California gulls have recently increased their numbers on Alcatraz and they did so markedly in the summer of 2010, perhaps because the South Bay salt flats that brought them so much reproductive success in the last thirty years are undergoing conversion to tidal salt marshes. Some of the displaced birds may have bred on Alcatraz.
An interesting tidbit from Alcatraz's pro biologist: the California gull eggs are laid and hatched a week prior to those of the larger and more numerous western gulls. It's hard to say but this may offer the Californias a tiny bit of protection against their larger cousins.
Both western gulls and California gulls also breed on the Farallone islands just 27 miles outside the Golden Gate. There, the California gull eggs and young are universally predated by western gulls, giving the impression of impermanence to the California gulls' first recorded nesting habitat on the open ocean.
The news isn't all bad for our CAGUs... in 1982, they sported 200 breeding birds in the San Francisco Bay Area. The recent salt marsh restoration not withstanding, they reached 46,800 birds in 2008. Holy birds, indeed.
On Friday... a special seabird has returned to us. You might say that it has 're-terned!' Haha, puns are awesome.
Friday, August 20, 2010
NEW FALCON
We've all been biding our time, waiting for the late autumn wave of migrating raptors that might return our departed femme falcon to Alcatraz. She spent the winter of 2009/2010 with us and we want her back:
She tore flesh from flesh on the top of tall buildings and we dearly miss her. Sadly, the falcon sighted recently isn't her, but we were happy to finally get a glimpse of it ourselves:
While it appears to be a female, it isn't our female. It's definitely a juvenile, having emerged from the egg as a tiny ball of falcon fluff earlier this summer. I tried in vain to see if we could find a band on her but she was so far away that I couldn't quite manage it.
When falcons fledge, quite naturally they leave their parents' territory and begin to explore the world around them. I'd imagine that every year Alcatraz is visited by a few juveniles recently fledged by the breeding pairs in San Francisco and the bay.
Just had to link to this:
Birdchick yearns to bird with both Jackie Chan and Owen Wilson... and she yearns to engage them in still other extracurricular activities. One activity involves a certain kind of sandwich. Another involves a harness. Oh, Birdchick... when did you get so suggestive? I truly didn't see it coming.
Monday, August 9, 2010
Brootality on Alcatraz is dished out by the ton, not the pound or the ounce
Warning: This post contains highly detailed images of a dead bird
Not all gulls survive to be the subject of a thoughtful, well composed portrait.
Newly departed birds like the fellow below appear just about every day on Alcatraz. Collectively, adult western gulls treat their young with positive br00tality:
I am grateful that the flies that colonized this guy appeared to be of the common variety. As veterans of the Alcatraz autumn are well aware, the island suffers from a miserable fly season.
The culprit is a strange and exotic insect that specializes in breeding deep within the corpses of cormorants and perhaps other waterbirds.
Once these grubs take to the wing, they terrorize human beings. Other flies actually fear human beings. These guys, by contrast, will evade your swats and slaps positively undeterred in landing on your hair, your neck, your cheek or any other part of your body that might serve to gross you out.
I've had one on my eye. No joke there. God knows what it wanted with my eye.
Rogue Cormorant Apprehended!
This guy was apprehended by our concerned NPS staff. Call it an immature Brandt's cormorant. That's what it is.
The happy fellow was arrested while gleefully marching along the road that stretches from the dock up to the cellhouse. The bird meant no harm to anyone and was apparently healthy but was friendly enough to make itself very suspicious.
Brandt's cormorants are notoriously timid and flush at almost any cause.
This one, however, was so comfortable in the presence of human beings that apprehending it was about as simple as throwing a towel over it and scooping it up.
Finally, acting upon the fact of this friendly bird being both strong and uninjured, and the fact that a gregarious disposition is unusual for a wild animal but is not any kind of cause for arrest, the bird was allowed to reluctantly leave its box and wander free.
Monday, August 2, 2010
Juvenile gulls begin to fly. Consequently, many die. (Also, falcon news!)
Take, for example, this WEGU's compromised position:
If you're new to the wing, this is what the excitement of flight can get you. It's a very common sight on Alcatraz.
Allow me to explain. This is what's called the Parade Ground:
Click on the image to get the full effect.
It's an area of flat pavement, dense shrubs and the remains of apartment buildings constructed to house correctional officers and then razed by the federal government in the 1970s after the closing of the prison and the end of the Indian Occupation. The structures were destroyed in order to ensure that a bunch of troublemakers could never again occupy the area and use it to showcase a loud, chaotic and violent mess.
Clearly the government didn't see this western gull colony coming. The gulls breed on the parade ground in huge numbers in a tightly packed configuration. There, they screech, squawk and fight one another in long and bloody engagements.
Then, as nesting season progresses and the eggs hatch, infanticide is suddenly on the menu and the adults happily indulge. When chicks are small enough to swallow, an adult gull will occasionally regurgitate a pellet containing the tiny indigestible remains of one of its own species.
Then, as the young gulls learn to fly, they've suddenly got a novel means to trespass upon the territories of others. And far be it from an adult WEGU, so imposed upon, to forego a shot at violence:
One pair of gulls has been especially prolific thus far in nailing invaders:
The two living juveniles in the above picture reside in this territory and their parents aggressively defend it. The other two birds, open and horizontal, meant no harm. They were learning to fly and they were flying badly. They were unfortunate enough to stumble into this territory which happens to be bordered by the foot tall remains of a small building. As these two accidental trespassers tried to escape, they failed to achieve enough altitude to clear the short wall and they were killed.
Most gulls are luckier, managing to evade the violence of the adults and escape with their lives. Many young gulls on Alcatraz survive to continue their development but retain these badges of honor, sustained in combat with the older brutes they hope to become:
That is not a good haircut. You'd better believe I would get my money back.
Falcon News!
One of our awesome bird biologists has spotted and photographed an adult falcon on Alcatraz. It's been a while. Our maturing male falcon appears from time to time and was last seen in late June.
On seeing the picture, I immediately took it to be a female. When I bounced my suspicion off of BourbonHawk, she opined that if turns out to be a female, it's probably too dark to be our friend from last year.
After reviewing the photos, I think she's right. It may be a female peregrine, but it's not our female peregrine.
One park ranger and one Parks Conservancy employee have also reported seeing peregrines recently, but no sightings have been made on birds occupying our peregrines' familiar preferred roosts, which is an additional consideration in favor of this being a bird new to Alcatraz.
If this is a female with designs on hanging around for a while and if our heroic young tiercel is still about, this should make him very happy indeed.
The island's gulls knew this day would come
And they've been practicing their battle moves on anything at all with a raptor silhouette:
Here, they harass a harmless turkey vulture.
The video is short but the chase was much longer. The vulture's reaction to the harassment was easy to read and was something along the lines of: Ugh! What? And why? Do! Not! Want!
On the flip side, I had no idea that vultures were so agile in the air. Can I be excused for taking them to be slow, dumb and lazy?
At any rate, most birds hate the sight of a hooked beak and they will instinctively count it as a threat and mount an attack if they are able.
Their instincts fail to make the distinction between a peregrine falcon which sometimes uses its hooked beak to behead live prey and a turkey vulture which means no harm to most living things, but has a sharply hooked beak in order to open the body cavities of the already dispatched.
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