This past weekend, however, it became abundantly clear - spring has finally arrived!
near a breeding pond - 26 March 2007, Tompkins Co., New York.
Here, the first signs of spring begin with the reappearance of rain, around late March into early April. For many nature-loving biology students here at Cornell, this is the much anticipated cue for the local frogs and Ambystoma salamanders to migrate to nearby ponds and vernal pools for their annual orgies. To witness these mass migrations (and hear the sometimes deafening roar of so many calling frogs) is a pretty darn cool experience!
Other than the novelty of the whole experience, it's also great opportunity to learn about these cute little critters. For example, salamanders are somewhat unique among amphibians as nearly all other amphibians fertilize their eggs externally (sperm doesn't meet egg until after the female has deposited them). In most salamander species, males produce a "sperm packet" called a spermatophore which they release during amplexus with the females. This spermatophore is then taken up into the reproductive tract by the female to use for internal fertilization of the eggs.
More signs of spring begin to appear while the amphibian eggs are incubating, preparing to hatch another generation of tadpoles and larval salamanders. The remaining winter birds have mostly left and some locally breeding ("summer") bird species begin to return to the area. Trees are beginning to bud, plants begin sprouting, insects come crawling out of the woodwork and begin to fill the air again.
wintering grounds - 28 Feb 2009, Tompkins Co., New York.
Here again, we can witness this spectacle of migration, though this time on a much, much larger scale!
The past few days of warm weather and winds out of the south make up great conditions for bird migration: basically these weather patterns are a sort of climatological express train for birds wintering south of the U.S. When the weather is right, these migrants can catch a ride north high up on some of those northbound winds, maximizing their energy use over the long journey and minimizing the time spent in unfamiliar territory exposed to predators.
This spring, however, things are a little different. This weekend (April 25), we had near perfect weather to hail the arrival of our returning migrants. Being the bird-o-holic that I am, the start of spring migration is usually more than enough to keep me entertained.
This year, instead of out running around with my new telephoto snapping bird pictures, I have a new toy... a new 100mm macro lens! How does this change things? Stay tuned for "part II" where I'll share a few photos of the small-scale side of spring.
25 March 2007, Summerhill, Cayuga Co., NY