Wednesday, February 16, 2011

Signs of spring

The sixty-five degree days in Billings this week have a lot of us fooled into thinking that winter is over. Even the animal world has come alive as if spring were really here. This afternoon we glimpsed the first painted turtle of the year swimming in Will's Marsh. Painted turtles hibernate at the bottom of the pond during winter. When they settle in to hibernate, their respiratory rate and pulse slow down significantly. Their body temperature drops to less than 50% of normal. Since they are not active and are not trying to keep their bodies warm, they don't burn up energy. Therefore they don't need much oxygen at all, and can get by on what they absorb from the water through specialized cells in their tails. They usually warm themselves back up in the spring when the weather is warm and their food supply again becomes plentiful. The turtle that was "awake" this afternoon may have a shock ahead as the temperature drops tomorrow. It is not clear whether the turtle will return to a state of hibernation, or if it will stay active, and try to get enough food to stay warm. Going into hibernation might seem like a better option, but keep in mind that it takes a LOT of energy to warm a body back up out of hibernation; it is energetically stressful. What do you think the turtle will do? We'll keep looking for him as the temperature dips back below freezing in the next few days.

Another surprising sighting on our pond this week was a beautiful male wood duck. This mid-sized duck normally arrives in Billings for the breeding season (though there are populations that live year-round in the western half of Montana). Wood ducks nest in tree cavities or boxes provided by humans. Like mallard ducks, wood ducks are dabbling ducks (as opposed to diving ducks). They feed mainly on seeds and invertebrates, and occupy a wide variety of habitats: creeks, rivers, overflow, bottomlands, swamps, marshes, beaver and farm ponds. For more information, visit the Cornell Lab of Ornithology's website.