A Phenological Event: The Spring Surge of Swoope and the Arrival of Tree Swallows
Phenology is the study of the timing of biological events. February 24th was Spring Surge Day in Swoope. That’s the first day of the year I notice the Earth is really on the move. It’s not necessarily the day the first daffodil blooms or the first warm day of spring. It’s a day when the energy of life seems to be surging in every creature. Every bird is singing, plants are growing, snakes are sunning and bees are buzzing. You can see it, hear it, smell it and feel it. We don’t have a word for it but I know when it happens. (This day often corresponds to the day most students skip school.) I call this Spring Surge Day and in Swoope, Virginia it’s usually the day male Tree Swallows arrive from Central America to stake out their nesting territories.
February 24th was Spring Surge Day in Swoope, the day Tree Swallows arrived!
All Swallows that we see in the temperate region of America are Neotropical migrants. This means they winter in the tropics and migrate north to nest and raise their young. Tree Swallows have traveled more than a thousand miles to get here. Their summer range is expanding northward and they have been arriving earlier almost every year since I have lived in Swoope. Last year the Swallows arrived on February 28th, the year before they arrived on March 8th, and in 2006 they arrived on March 14th. It doesn’t take ice core samples from Antarctica and NASA data to convince me that we are getting warmer, earlier. We can use just plain old scientific observation otherwise known as phenology.