How Low Can You Go?

Today was miserable.  Tomorrow isn't looking that much better, either.  Every year, it seems like winter meanders erratically through December and January, but when it hits late February, it's like it realizes that its time is almost over.  It's then that we get the worst of the cold.

On nights like tonight, listening to the wind scream outside, throwing up armloads of snow, I can't help but worry about the animals at the zoo right now, hoping that they are all cozy and snug inside.  No reason that they shouldn't be fine - I checked the heat lamps, added tons of bedding, and put up wind-blocks - but it's still easy to worry.

This being an unusually brutal winter for us, we've had to respond accordingly.  Some of our animals who faced winter outdoors for the last several years began to quake in the face of this one; animals that hadn't seen the inside of a building for years were caught, crated, and transported inside for the worst of the season.  This has led to a little grumbling and bickering among the staff, especially with some of the older members grousing about how unnecessary all of the effort it.  In their (not uninformed) opinions, the animals will make do outside, as they have for years past.

I agree... to a point.

Few aspects of animal care are as subjective as temperature guidelines.  At one zoo where I worked, the alligators went outside in the beginning of March and they came in after Thanksgiving... that was it.  There were mornings when I came in and found the layer of their pool covered with a film of ice, with only the tips of their noses frozen above the surface (this is what wild American alligators will do in some of the colder parts of their range).  At another zoo, it was considered inconceivable for the gators to go out if there was a chance of temperatures below 50 Fahrenheit.

There aren't only differences between institutions, but between animals, even those of the same species.  I once worked with two birds, both males of about the same age and same species, housed in side-by-side exhibits.  One faced winter with calm indifference every year.  The other had feet ravaged by frostbite.  No one could explain why the one bird was so cold hardy, while the other - after his ill-fated first winter outside - had to be bundled indoors every December.

A big part of the confusion comes to differing opinions as to what temperature guidelines are supposed to achieve.  Some people think that it's simply what the animal can survive without signs of injury or illness.  Most animals can tolerate temperatures considerably colder than what they would experience in the wild, provided that they are given shelter from the cold to use as they desire.  The problem with this is that it simply comes down to endurance and survival; the goal shouldn't be for the animal to survive, it should be for it to thrive.  I could survive a 40 degree night if I were locked outside naked... but I wouldn't be very happy in the morning (nor, I suspect, would my neighbors).

I don't want to make the "leave 'em outside" crowd seem heartless.  They have their reasons for wanting to keep the animals outside.  For one thing, it's less stressful on the animals, especially if the indoor area in question is a building on the other end of the zoo. (A way to mitigate this is to have indoor holding areas attached to outdoor enclosures - it can be more expensive, but does allow animals to be moved back and forth with less stress, and allows you to move animals quickly based on sudden changes in weather, like hurricanes). For another, indoor areas are almost always smaller, and no one likes being locked in a smaller area.  Thirdly, temperature shocks can be hard on an animal.  If you pull a bird inside for the winter, you might need to keep said bird inside for quite a while, until the indoor-outdoor difference isn't so great.

My current zoo tends to be a little more conservative with temperatures than I am on some species, a little laxer on others.  I spent much of my early career working for a director who seemed determined to push every animal in the collection as far as he could on the path towards cold-tolerance.  As a result, I've seen some of his failures in that regard.  Having seen the impact the extreme cold can have on animals, I'm always inclined to error on the side of caution these days.

Not to anthropomorphize, but if I'm cold, I usually figure they're cold.