The Backyard Science group regularly features the Daily Bucket. Some of us look at tiny creatures under a microscope. Some of us talk Irish to calm animals we've encountered on a walk in the woods. Some of us will pull their car over onto the freeway shoulder, to get a good ID on a soaring bird.
Me, I'm not an animal cop, but I play one on the Internet. When I finish spinning my yarn,
please add your own observations in a comment. Insects, weather, meteorites, climate, birds, and more are all worthy additions to the Bucket. Include, as close as is comfortable, your location. Your viewpoints will broaden the outlook of everyone who reads the Bucket.
Something's been killing the killdeer. Every springtime, in this valley in northwest Oregon, a half dozen mating pairs of these quirky birds fall in love, nurture eggs, raise little killdeer, and get the killdeer population up to about 20.
And then over the grey winter months of January and February, the killing starts. This year, it started even earlier; yesterday.
I was walking at 7 am, through the fog that clung to the low hills on the golf course where this killdeer flock chose to live, and I came across the crime scene; two throw-rug-sized clusters of brown and white killdeer feathers, a few feet apart. There were too many feathers there to hope it was just a skirmish.
Mated killdeer often forage side by side. It looked like these two had both been sent to the great hardpan in the sky. At least they went together.
I knelt nearby, searching for clues. I knew intuitively the golf course had too much open space, and too little cover for the killdeer to thrive unmolested. But that's how the killdeer liked it. Maybe it reminded them of the beach; they were beach birds.
Sometimes I tried my Irish brogue on them, urging them to hide in the tall fescue grasses, among the lost golf balls, but my accent was unconvincing.
I knew a dumb animal flatfoot like me couldn't identify this canny predator by myself. I sought help from an expert at the FBI (Font of Bird Information) Behavioral Analysis Lab.
In this instance, it was fellow KOsser Arch Teryx, who in months past, kindly exchanged several private messages with me and provided reference materials on clues to identify predators. Here's the crucial details Arch provided:
Hawks and owls will pluck, but hawks do not kill at night, and if the prey is too big to just swallow in a gulp (i.e. bigger then a sparrow), owls will sometimes fly off with it elsewhere, and sometimes pluck in place.
Doing a little more research, Arch came up with this:
"Hawks pluck birds, leaving piles of feathers on the ground. Beak marks can sometimes be seen on the shafts of these plucked feathers. Owls also pluck their prey, but at times they will swallow small animals whole.
Many raptors (especially red-tailed hawks and other buteos) feed on carrion. The plucked feathers can often determine whether a raptor actually killed an animal or was simply “caught in the act” of feeding on a bird that had died of other causes. If the feathers have small amounts of tissue clinging to their bases, they were plucked from a cold bird that died of another cause. If the base of a feather is smooth and clean, the bird was plucked shortly after it was killed.
Raptors often defecate at a kill site. Accipiters such as the goshawk leave a splash or streak of whitewash that radiates out from the feather pile, whereas owls leave small heaps of chalky whitewash on the ground." [Ed note: this is to "lighten the load" so they can take off again.]
The site is http://icwdm.org/.... an excellent site about controlling bird damage from hawks and owls on domestic fowl.
This is another good site (centering on purple martins): http://purplemartin.org/....
In the end, Arch concluded, my hunch about it being owls is the most likely explanation. The tell is the state of the plucked feathers. If the bases are clean, it's an owl (or a twilight hawk). If they have their basal sheaths, meat on them, the pile of feathers looks really "messy" (lots of leftover meat or meat with clumps of feathers) or there's dismembered limbs, it's mostly likely a fox or other small mammalian predator.
That advice ran through my mind as I peered at the remaining feathers. The base of the left-behind quills were squeaky clean. There were also no viscera, flesh, or large parts left there; just a couple handfuls of feathers from a night attack. I think now I was looking at the killing ground, and the feathers were evidence of the site of the attack, not of the consumption of the prey, which took place elsewhere.
Case Closed. It was owls. This time.
And now it's your turn to tell a little about the goings-on where you are, and hopefully your local nature is not quite so red of tooth and claw. I may not be back to respond until just before lunch, because I'm going back to the crime scene tomorrow morning, hopefully for another look and some pictures.
"Green Diary Rescue" is Back!
After a hiatus of over 1 1/2 years, Meteor Blades has revived his excellent series. As MB explained, this weekly diary is a "round-up with excerpts and links... of the hard work so many Kossacks put into bringing matters of environmental concern to the community... I'll be starting out with some commentary of my own on an issue related to the environment, a word I take in its broadest meaning."
"Green Diary Rescue" will be posted every Saturday at 1:00 pm Pacific Time on the Daily Kos front page. Be sure to recommend and comment in the diary.