6 September 2012 – no casualties but a persistent cheesburger

Okay, well that little warbler keeps hanging around.  It seems in good health; I even watched it eat an insect of some kind yesterday.  So it’s hanging around the north side of the NRC, but it’s at least finding some food and doesn’t appear at all stunned.  In fact, it’s in such good shape that’s one of the reasons I’ve been unsuccessful in herding it away from the building.

The more interesting story this week concerns scavenging, or the lack thereof.  I’ve written before about how I think efforts to determine the scavenging rate at building and tower studies are misguided.  First, there is no one rate.  It changes all the time and can go from near 0% to near 100% if one raccoon or rat or crow or cat figures out that fresh birds are to found at some building.  I’ve had birds I left out that lasted for months and birds that lasted less than a day.  Removal rate is really variable.

The other problem I have with removal rates is that the slight increase in precision of mortality estimates we get from factoring in scavenging or removal rates just begs the question.  Why do we care to know more precisely the number of birds that died at this spot?  No one has been able to provide an answer for me.

So this week it’s been fun to consider the cheeseburger, specifically the one that I found Sunday morning.  Clearly, it had fallen off of someone’s bun the night before during a tailgate party for our opening football game.  It was sitting there on the sidewalk, right in front of one of the entrances to the NRC.  It was so fresh that it actually made me a little hungry.  And it was completely untouched for 4 days.  Yesterday, I noticed that it had been nibbled on and moved from its original location, but it’s still there.  There is an unscavenged cheeseburger that has been sitting out in the open for 5 days on a college campus with daily clean-up crews scouring campus, flocks of Great-tailed Grackles, starlings, rats, opossums, raccoons, skunks, cats, etc.  I’ll keep you posted on it.