Bird migration is a phenomenon that has puzzled and intrigued people for thousands of years. In recent history waterfowl biologists have developed studies to identify the factors and cues that play a part affecting the fall and spring migration of ducks. Some recent studies have looked at the impact of wind direction and winter weather severity. Other research has examined how habitat availability and quality may influence a duck's seasonal decisions. Still, additional studies have focused on the influence of human related disturbance on the distribution of waterfowl.
This fall's mild weather, rising and falling flood waters, and hunting pressure on public and private land have all probably influenced waterfowl activity to a degree and in turn affected our waterfowl hunting experiences this season. Just like everyday life, waterfowl ecology and the seasonal movements of these birds are more complex than what one simple explanation can answer. While that might frustrate some, I find it encouraging and perhaps a hint at why these birds are so resilient. When you get down to it, these birds are hardwired to respond to a variety of situations on a regular basis, but also retain some flexibility in their reactions.
Emerging studies in quantum biology have begun to uncover some of this hardwiring circuitry that helps birds navigate across complex landscapes. That's right, quantum biology, a weird marriage of different sciences at the nano-scale where physicists and biologists look at how the interactions of atoms ultimately affect an animal's abilities. I know it sounds like a weird science fiction novel, but it is legit and they are uncovering some pretty cool stuff.
For years biologists have theorized that birds can sense the earth's magnetic field and use this internal compass to guide their seasonal treks across the globe. Recent research examining the eyesight of several species of birds has uncovered that this extra ability is partially related to the light-sensitive cells in a bird's retina. Within specific molecules the interaction of light and the magnetic fields of electrons produce a sensitivity in which these birds can "see" the earth's magnetic field as they turn and move their heads. However, to use this extra "power", the birds also have to be able to see their landscape clearly to help orient them. So once again, a crystal clear explanation doesn't answer all of the questions, but it does add to the notion that the natural world builds off of its inherent complexity.
While I sit out in the marsh or stand in the woods waiting for the next batch of ducks to pass by, I like to ponder what they are keying into as they fly from one spot to the next. What kind of information are they processing? How do they navigate from prairie Canada, through Missouri, and on further south? This new research doesn't necessarily simplify my questions or the potential answers, but then again, I didn't really expect it to either. Nature always has unexpected surprises and another layer of complexity that links one aspect to another.