Friday, October 13, 2017

Waterfowl Migration Picks Up

Down at South Platte Park this morning, the diversity of waterfowl had significantly increased.  While the number of mallards and Canada geese was below normal, American widgeon remained the most abundant species, followed by gadwalls, American coot and pied-billed grebes.

Making their first appearance were a dozen or so green-winged teal, a pair of ruddy ducks and a lone northern pintail; among the common winter ducks yet to arrive are buffleheads, common goldeneyes, ring-necked ducks and scaup (both lesser and greater).  Though common mergansers are permanent residents here and a few hooded mergansers have been encountered in recent weeks, they were not observed today.

As our climate warms, the autumn waterfowl migration will likely occur later in the year (as I have noted in recent years); unlike songbirds, which migrate in response to the daylight cycle, waterfowl move south in concert with the availability of open water and food.  Perhaps our recent cold front, which brought snow to the Front Range, is responsible for this first wave of migrants but, since warm weather has returned to the West, we may have to wait a while for their cohorts.