11/19/2024
🌿 From the Field
“One cold morning while walking near the River Campus, I noticed a small group of mallard ducks on the Arkansas River. Why wouldn't these ducks migrate for the winter like so many other waterfowl species do? Luckily, they have several adaptations that allow them to survive living in Pueblo for the winter.
First, these mallards spend most of their time searching for food. This large time spent eating creates a small fat reserve which they then live off of when conditions are really harsh. Secondly, the ducks also spend a lot of time resting which conserves energy. While resting, the mallard will bring one foot up towards its body and bury it in the feathers. Just like that, they have eliminated nearly 50 percent of their heat loss. It also twists its neck toward its back and buries its bill into feathers.
Finally, the mallard has a unique heat exchange between arteries and veins in their feet. The arteries and veins are so close together that the warm arterial blood actually warms up the cold venous blood coming from the foot so that the duck's body isn't "shocked" by cold blood. Remember, that duck's foot might be in close contact with ice! A slight warming of the venous blood can keep the foot from developing frostbite. With this system, having a foot temperature closer to the outside temperature actually conserves heat.
So, what can humans learn from these adaptations that a duck has to help us be more comfortable in cold conditions? On cold days, our bodies require more food as we are burning energy just to stay warm. Get something easy to snack on like nuts, dried fruit, or protein bars while hiking, snowshoeing, or skiing. Like a duck, you have permission to eat all day long!
Humans don't have a unique heat exchange system in their feet or highly insulated feathers covering our bodies, but we can easily dress in layers including our feet, hands, neck, and head. By covering any exposed skin, we can minimize heat loss and stay warm. The adaptation that I most enjoy taking on in winter is resting a lot to conserve energy. In fact, I feel a nap coming on right now!”
- Ranger T