Saturday, February 11, 2017

A Surge of Hormones

On this cool, sunny morning along the Colorado Front Range, spring was in the air.  While the afternoon temperature will be at least 20 degrees cooler than yesterday, the birds and mammals on our Littleton farm were responding to the lengthening daylight and their breeding seasons will soon begin.

Both Eurasian and mourning doves delivered their seasonal tunes, a northern flicker offered his first hysterical calls of the season and a pair of blue jays had switched to their softer, more musical voice.  Male house finches have taken on their brighter red plumage of spring while eastern cottontails chased one another across the pastures, soon to produce their first litter of the year; by late summer, the females born in February will have litters of their own.

Joined by the first faint greenery of spring, these revelers do not know that the heaviest snows of the season likely lie ahead.  They are merely responding to a surge of hormones, nature's annual gift to their species.  Unlike humans, subject as we are to cerebral override, they will always heed the call.