T’is the season for autumn shorebird migrations. More than five billion birds take flight across North America at rates of tens of millions a day. Here in the lowcountry, it is not unusual to see several hundred birds overhead and navigating with a synchronicity that boggles the mind. Experts say their aerodynamic maneuvering is partly done as protection from predators, but it is also ergonomic. Flying close together allow birds to take advantage of wingtip vortices that provide lift from the wings of the birds ahead. It is similar to how the bicycle peloton works its magic in road racing competitions, when it catches and passes the break away leaders. Group velocity is simply faster than any individual rider. It takes less effort working together and in migration, efficiency is a life and death matter. There is also a theory that bird communications are only possible or at least improved when flying in close proximity to one another. Whatever the reasons for this dramatic aerobatics, it is amazing to witness and a challenge to photograph. The medium sized sandpiper can reach speeds up to 40 mph.
Photo Tip
During the shorebird migrations, I spend a lot of time on the water exploring where different birds are congregating. I scan high oyster banks and sand spits above the water line around high tide. Birds have their favorite rest stops, even though they look relatively the same to us. I also keep a close eye on the weather and the tides to determine when will be the best lighting and water levels. I was able to capture the image of this flock of Dunlin and Sandpipers in my kayak using a 300mm lens. I like to keep a 300 or 400mm, fixed focal length lens handy. They are lightweight with quick focus capabilities, however a long zoom lens is also useful when trying to frame and compose a subject matter that is constantly in flux. Remember when shooting wildlife images no two trips will be the same but being prepared allows you to remain in the moment with the ever changing natural world. See the 2011 Lowcountry, South Carolina Wall Calendar (shipping only $3.00 till Dec 15th)
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