Importance to waterfowl
The Gulf Coast Joint Venture recently established midwinter population objectives of 13.7 million ducks and 1.3 million geese (Barry Wilson, GCJV, pers. comm.). Duck population objectives are based upon 1970s winter distribution and breeding population estimates. Goose objectives are based upon December goose survey data from the mid-1980s.
Gulf Coast habitats are of particular significance as migration habitat to blue-winged teal, and as winter habitat for northern pintails, gadwall, wigeon, green-winged teal, redheads and lesser scaup. The GCJV winter population goals for pintails and wigeon represent approximately 25% of the NAWMP continental breeding population goals for these two species. For gadwall and green-winged teal, the GCJV midwinter population objectives represent over 95% and 80% of the continental NAWMP breeding population goals, respectively. Clearly this region is the most important wintering area for both species in North America. Mottled ducks are resident to peninsular Florida and the Gulf Coast from Mobile Bay west and south to Tampico, Mexico, which is approximately at the southern end of the Lower Laguna Madre. Approximately 90% of the mottled duck population, which may number between 600,000 and 1 million birds (LDWF unpubl. data, Barry Wilson, GCJV, pers. comm.), reside in coastal Louisiana and Texas. An undetermined, but apparently increasing number of fulvous and black-bellied whistling ducks now breed in southwestern Louisiana (mostly fulvous) and coastal Texas (mostly black-bellied).
Notably, the population objective for lesser scaup (2.5 million) does not include a substantial but undetermined number of birds that winter offshore in the Gulf of Mexico (Barry Wilson, GCJV, pers. comm.). However, even without those birds in the goal, it represents over 30% of the NAWMP continental breeding population goal, and when offshore populations are added in, perhaps over 40% of the continental breeding population estimate for scaup may over-winter in Gulf Coast habitats. Similarly, the winter redhead and canvasback population goals represent over 55% and 12% of the NAWMP breeding population goals. Nearly all redheads wintering in the region use habitats in the Laguna Madre.