Monday, March 21, 2011

Roseate Spoonbill

Roseate Spoonbills attract birders to both the Texas and Florida coasts.  The oddly shaped bill is swished through the muddy water for invertebrates.  Many prey items may be kicked up as the bird walks through swampy water.  Judging by the well-vascularized bill visible in the the photo above, I was not surprised to discover that spoonbills are tactile feeders--snapping their bills closed when they feel prey between their mandibles (Dumas 2000).
The birds in the first two photos are juveniles, as indicated by their feathered heads.  Adult birds, like the spoonbill below, become bald.  The head skin becomes pale greenish blue. Spoonbills in the United States were nearly extirpated by the 1940s.  Now numbers are increasing, but the species is of special concern in Florida and Louisiana. Texas, Louisiana, and South American populations appear to be disjunct from those of Florida and the Caribbean.  If genetic isolation continues, one might predict isolated populations accumulating genetic differences leading to speciation.  This situation, however, is not well investigated (Dumas 2000).
The top two photos were taken in the Merritt Island National Wildlife refuge just east of Titusville, Florida, and the bottom ibis fed near Flamingo, in the Everglades National Park.

No comments:

Post a Comment