Posts tagged “cold

Raven yanks another raven’s tail

The average adult raven is about 2.5 pounds and it’s hard to tell adults from juveniles.  The below video shows a power struggle between ravens at a food source.  At the very beginning you can see a raven on the far left grab another raven’s tail feathers with his beak and pull him or her away from the food.  Another seems to join in.  (By the way, if the video is blurry find the settings in the bottom right hand corner of the player and change it to a higher resolution.  Youtube automatically chooses a low setting so it will download faster.)

After reading Ravens in Winter, a book by Bernd Heinrich, I’m inclined to believe that the commotion going on in the video has to do with a power struggle (to gain access to the food) between the juvenile birds and the adults.  According to Heinrich, adults are usually silent at carcasses (dead animals in the wild), and juveniles are very noisy.  The juveniles “yell” at kills and make a commotion, possibly to attract more juveniles to the kill, in order to compete with the adults and gain access to the food.

Heinrich “proves” through observation and careful note-taking that ravens actively recruit other ravens to food piles.  He speculates, after studying raven behavior for many years, that this recruitment is not necessarily altruistic, or done in order to get the favor back some day.  Instead, it is probably related more to “gaining or maintaining access to the food than to sharing the wealth.”

Juveniles actively recruit, in order to overwhelm by sheer numbers, the adults at the carcass, so that the adults will give up defending the carcass, which they do when they are just too outnumbered.

So if we can extend this power struggle at carcasses in the field to city food (trash) then it’s possible the squawking raven in the video, the one being pulled from the food by his or her tail feathers, is likely a juvenile, being bossed around by the adults, who are not as vocal.

I strongly encourage any bird lover to read Ravens in Winter.  This bird that I see nearly every day of my life is actually quite mysterious and Heinrich helps us understand their possible and likely motivations.

Thanks for reading!  Happy New Year!

 

Advertisements

Black-Capped Chickadee Beak Deformity

Chickadee with beak deformityI made this little animation to show how this poor chickadee was being bothered by its beak deformity.  Every so often it would rub its beak against the edge of the bird feeder like this.  It appeared relatively healthy so it must have been able to eat satisfactorily, but apparently this deformity causes it to be obsessive about trying to scrape off the excess beak.


Image

Raven, in the winter sun

Raven in Tree


Bird Congregation

I don’t think this is a very common sight on the coastal plains of northern Alaska (or anywhere?), but as my husband drove in to Prudhoe Bay last spring, he spied this unusually large gathering of various birds.

Raven, Rough-Legged HawkThe rough-legged hawk and raven seem to be acting as sentries over the vast flocks, but they are watching for sinister purposes.

Rough-legged HawkYes, watching carefully.

Rough-legged hawk eating a duckSure enough,  a hawk has gotten herself a meal.

Rough-legged hawk But really, how can you blame her?

Short-eared OwlA short-eared owl perches nearby.

Kind of hard to believe that little twig can hold him up.  He must be all fluff.

And life goes on….


Puffed Up Pigeons

Pigeons in Fairbanks during 30 below zero (F) weather

It’s amazing that any pigeons at all make it through our frigid Fairbanks winters.

This year we saw several weeks of sustained 30-40 below zero (F) weather and they are still flying around!  (This photo was taken when it was about 30 below.)

Some perch at night in attics and eaves (and I assume even sometimes in trees if they have to although I don’t know if I’ve ever seen one in a tree).

Some people throw seed on the ground outside their homes throughout the winter, and the birds congregate in those places during the day.   Not so much different then me feeding little redpolls and chickadees I suppose!


A chubby Redpoll can’t stop eating

Fat Redpoll

A few years ago a chubby Redpoll visited our feeder.

This antique dish had broken and I couldn’t part with it, so I put seed in it, and the redpoll adopted it.  He (or she) sat right in it and ate and ate and ate.  Like his full switch never got flipped.

He moved quite slow.  My husband and I figured that he was missing some kind of instinct or characteristic that gives birds their fast-twitch, jumpy nature.  Probably something that they need to survive.

He’s puffed up too because of the chilly weather, but this bird was quite unusual in that he was fatter, slower, and never flew away intermittently like the other birds.  He was totally content to eat continuously, rarely looking up.  This was the very last photo I took and out of at least 20, this is the only time I got him looking up.

After watching hundreds or even thousands of birds at the feeder over the years, this little guy’s behavior was profoundly different than all the others.


To Feed or Not to Feed

Junco that just hit the window

This junco hit our second story window and sat stunned, but alive, here on the ground last summer.  Juncos are sweet little birds that we see from May to September all around our house pecking at seeds on the ground.  They visit our feeder during this time but mostly stay on the floor of the deck or on the ground under the feeder, hopping around picking up fallen sunflower heart pieces and birch seeds.  They can leave so late in the season, I believe, because they are only flying as far as the southern coast of Alaska where it doesn’t freeze so hard in the winter.

Junco that hit the windowMy husband and I immensely love watching our feeder birds:  redpolls, juncos, chickadees, and hairy and downy woodpeckers.  He often places small amounts of bird seed on the snow mounds that cover the deck railings and flower pots in the winter so that redpolls don’t have to mob the feeder and so that we can see them closer.  We stand at the window and marvel at how they can live at 30 below zero, and at their quick movements and little arguments.

But I wonder that having a bird feeder is the best thing for the birds.  Many birds hit our windows, but by far most of them end up alive (though certainly a bit damaged afterwards).  After they hit the windows as they sit stunned until they are able to fly away, they are undoubtedly vulnerable to predation.  There’s a neighborhood cat that I fear visits in the wee hours of the morning in the summer and I have no idea if it uses the feeder as a baiting station.  I have no evidential reason to believe this but am concerned.  Other than that cat our neighborhood totally lacks outdoor cats as far as we can tell.  This one we’ve only seen twice in our 5 years here.  (And our two cats don’t go outside without being chaperoned.)

Feeding birds seems on the surface not a bad idea.  But is it good to get them reliant on what we provide?  So that they lose just a little bit of their natural foraging skills to their eventual detriment?  What about the seed itself… are there pesticides on it, or fungicides?  Is it even good for a redpoll or chickadee to eat that much sunflower heart instead of what it would normally find in nature?  Could there sometimes be mold on the seeds that would be dangerous to the birds?  Is feeding birds related to the sickness of chickadees that results in 6-10% of them having beak deformities?  I’ve read up a bit on this topic and there are not a lot of answers to be had (although plenty of guesses and opinions).

So unfortunately, I’m not convinced that feeding birds is the absolute right thing to do, but I’m unwilling to give it up unless I see direct evidence that it harms them more than it helps them.  The only way I know for sure that it harms them is when they hit the windows.  Redpolls eating seed outside windowI’ve went to great lengths to try to prevent it, such as wiring and beads that I once strung across our largest window for a few years.  The thing is, I know that they would hit the windows even if we didn’t purposefully draw them here to our house with food.

Alas, it would be a sad sad day for my husband and I if we were to decide that the harm to the birds outweighs the benefits (to us and the birds).

You can see here the redpolls chowing down today on the seed my husband has strewn on the snow in front of the window.  The temperature gauge doesn’t go colder than 20 below – it’s about 30 below zero (F) right now.  I can’t imagine those poor little guys can’t use some extra food at this temperature!

But am I justifying?  This summer I plan to try something else on the windows:  CDs strung on wires or string.  I’ve also switched out the bird feeder when it was just too hard to clean anymore.  Any tips are welcome!  Thanks for reading.