Thursday, February 25, 2016

Black Duck

John Holden and I enjoyed a fruitless expedition to Presscott, Wisconsin. We saw very few birds. On the way home, we stopped at Lake Rebecca Park near Hastings, Minnesota. Along with 150 Mallards, swam three ducks that were clearly much darker than the others. You can see two of these ducks in the first photo—American Black Ducks. Their finely streaked throats and relatively unmarked, greenish-yellow bills confirmed our identification. The American Black Ducks isolated themselves from most of the Mallards.

“Hybridization of an abundant species with a less abundant and declining one can lead to genetic extinction of the species with the smaller population” write Longcore et al. (2000). When I was young, that scenario was playing out for the American Black Duck.  Mallards were becoming abundant and hybridized with Black Ducks. The Black Ducks were over-hunted as their northeastern North American breeding range was degraded. But, thanks to the Black Duck’s wide range and to stringent hunting regulations, this species appears to be on the rebound. 

No comments:

Post a Comment