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.
Wednesday, July 28, 2010
Young WEGUs excitedly perform "I can fly!" dance!
This particular gull is known to us as Beezel Jr., named in honor of one of BourbonHawk's ex boyfriends. Beezel Sr. scored a 1500 on his SATs, dropped out of school and has gone on to imbibe copiously and manage a RadioShack. That's a true story and it's one reason why I love this city. We have much higher hopes for this young gull, but I digress...
For a brief moment, before these animals fledge and become violent, desirous and trife, they are little balls of fuzz and optimism. Earlier this year, I took this footage of a much younger western gull, apparently beginning to exercise the tiny wing muscles that will eventually power it into the air:
The seemingly drunken twirl and tumble is the signature dance of the baby gull and it's one of the cutest animal behaviors that I've ever seen.
At this late date, most young gulls on Alcatraz are very deep in the process of losing their fluffy down and as the first video shows, a few of the older and braver birds are actually starting to grow the hardware necessary to contemplate life in the sky.
While these young gulls are poised to gain a measure of independence from their parents, less fortunate others are only now entering the world of the living:
And this story begins much earlier in the year on the island's western slopes. In 2010, this was the very first gull nest we observed on Alcatraz:
As far as we can tell, this nest was the first to bear gull chicks, though they would have done just as well to stay in the shell as this was the sad result:
Their entire brood died within a day of hatching. We began to refer to them as 'the worst parents on Alcatraz'.
And they may be, though they aren't through yet as we recently caught them incubating a new egg:
And before long...
As it turns out, this pair was incubating not one but two eggs... and equally apparently, this pair, challenged in the ways of parenting, has stretched its tally of dead young ones to four on the season. The new baby gull in front and to the right is not sleeping. The casualties of nesting season always seem to run unacceptably high.
Baby gulls die all the time:
We at Maganrord have no idea what allows one pair of gulls to successfully rear four young ones while another pair suffers two total brood failures in a single season. Perhaps they've just had a bad year. Maybe they're simply bad at this. We can't say for sure.
Another gull pair on Alcatraz is rearing a second brood after the failure of its first:
First we saw this:
One had hatched and a second egg was clearly visible.
Although I don't have a picture of it here, the second egg has hatched and both chicks are doing just fine.
In contrast to the aforementioned pair on the west side of the island, this pair is always feeding its young or yelling at a human being that ventures too close. As parents, these gulls seem far more attentive and competent. I can't say why these gulls lost out on their first brood, but I suspect they'll do much better this time around.
Meanwhile, our more advanced juvenile gulls will soon be learning the value of their flight feathers. In nesting seasons past, I've learned that in contrast to our skilled adult gulls, newly airborne WEGUs are terrible pilots. They don't know how to ascend, descend, change direction or land.
Up next, the sad conclusion of our cowbird series. Spoiler: Please don't tame a bird in a national park. Bad things will happen.
Tuesday, July 27, 2010
Our secret identities
have been revealed! As well as so many other things.
Here we are, doing our best to sound interesting on Crosscurrents. It's a short piece, maybe 5 minutes tops, so please check it out if you've got the time. Thanks!
Here we are, doing our best to sound interesting on Crosscurrents. It's a short piece, maybe 5 minutes tops, so please check it out if you've got the time. Thanks!
Monday, July 26, 2010
Radio Maganrord!
Earlier in the year, the Maganrord team was interviewed on Alcatraz for Crosscurrents, an award winning local news program heard on KALW 91.7 FM.
Listen for us on today's edition between 4:30 and 5.
For those of you scoping us out for the very first time, I'd like to give you a dose of classic Maganrord:
In early February, we were given special permission to trod through the remains of our dormant cormorant colony, which collapsed dramatically in 2009 due to lack of food.
This is what we saw.
Our world famous female peregrine falcon has left us, perhaps for good, but we'll always remember the good times. Here, she takes an unknown alcid, perhaps a common murre.
Here, she takes one final bloody meal before spreading her wings and taking to the air. We haven't seen her since.
Read here about the feel good story of the season: Alcatraz's unlikely miracle of a goose.
And finally, in case you were ever curious about it, this is what it looks and sounds like when gulls slow things down and get a little romantic.
Stay tuned over the next couple of days. We're cooking up a report on the progress of the island's young western gulls and the conclusion of the cowbird series. Here's a partial spoiler: it ends very badly.
Sunday, July 18, 2010
Cowbirds III: Media deluge, appearance by a female adult and a bonus new GBH fishing video!
The little guy has become somewhat... tame.
Above, a visitor gets a little too close and had to be reminded of the rules that govern the treatment of wild birds in a national park.
But what's that weird growth his nose? He'd better get that looked at.
When it talks and moves:
The little guy is cute, bold, interactive and embarrassingly tame. For reasons I can't go into on this blog, I think it a fitting name for it would be Gil Jr.
Walking around the island today, scoping out small birds, I found several other probable cowbird juveniles as well, including two positive IDs on the west side of the island. There may be a cowbird breeding racket on Alcatraz and it makes sense. Cowbirds range here and we have the songbirds they like to victimize.
In our previous cowbird posts, I mentioned that egg laying cowbirds are known to sometimes linger around the nests they've visited to guarantee that their eggs are well treated by the forced adoptive parents.
Well, today I encountered what I believe to be a female cowbird:
I know these pictures are far from clear and the resemblance to the juvenile form is definitely strong, but the light trim around the flight feathers is much more subtle than that of the juvenile. The barring on the breast is more subtle and uniform.
The entire bird is darker, featuring much less yellow.
Her shape and gait are different. She looks more like a tall, confident blackbird than a pot bellied beggar and she pursued her business unaccompanied by any adoptive parents.
Great blue heron!
As the video closes, one of Alcatraz's bright and intrepid law enforcement rangers begins to raise the interesting question of how a great blue heron can hunt as it does when its eyes are located not on the front of its head but rather on the sides, which presumably hurts its ability to perceive depth and distance.
But you can't argue with the results, I guess.
Saturday, July 17, 2010
Cowbirds part two: Concrete ID and links both amusing and thought provoking
I found this awesome capture of a brown headed cowbird juvenile on Flickr.
And again, here is the bird I observed associating with the white crowned sparrow pair.
Finch like beak? Check.
Said finch-beak displaying bicoloring with darker upper mandible and yellow lower? Check.
Brown primaries with yellow trim? Check.
Black eyes, mottled yellow brown breast bars? Check and check.Fat little pot-belly? I don't think that one 'check' will do.
Links!
This rad NOVA Science Now video explores the cowbird way of life with sufficient mafia metaphors and kitch to show how overdone the gangster analogy was before I got a chance to have any fun with it. *Sigh* Also, Neil deGrasse Tyson does a mean cowbird themed Marlon Brando.
This equally rad post by BirdChick examines the ethical and legal issues surrounding the removal of cowbird eggs.
In this video, also posted by BirdChick, you can see a roadrunner nab a cowbird about 2 minutes and 45 seconds in.
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