Appendix 6.3(11) Continued 



Although waterfowl are closely related taxonomically , they show great 

 interspecific diversity. Each difference between species is indicative of 

 an evolutionary attempt to guarantee resource availability. It is clear 

 that some species have been more successful than others in exploiting their 

 environment. It would be valuable to compare the components of behavior and 

 morphology in greater detail with population dynamics, to increase our abil- 

 ity to project trends in their population numbers. 



Lesser snow goose {Chen caerulescens) 



m 



The lesser snow goose is the most abundant goose in the Chenier Plain 

 and has its wintering grounds heavily concentrated on the western Gulf coast 

 from the Mississippi River Delta to northern Mexico, although the primary 

 range extends only to Corpus Christi, Texas. It occurs in blue and white 

 color phases that reflect breeding populations in northern Canada; the color 

 phases were thought to be separate species prior to studies by Cooch (1961). 

 The blue phase is dominant in the eastern portion of the species range, and 

 the white phase is dominant in the western portions of both breeding and 

 wintering grounds. A color phase gradient extends across the Chenier Plain, 

 where the percentage of blues diminishes from 80% at Gueydan, 65% at Sabine 

 National Wildlife Refuge, 50% at the Louisiana-Texas border, to 20% at Ana- 

 huac National Wildlife Refuge (Schroer and Chabreck 1974) . These geese ar- 

 rive in the Chenier Plain with regularity during mid-October, and remain 

 until March or April (Louisiana Wildlife and Fisheries Commission 1962) . 

 Peak numbers in the Chenier Plain, as surveyed by the state wildlife agen- 

 cies, have varied from 300,000 to 600,000 with the greatest variation oc- 

 curring in Texas. Many geese that formerly used coastal marshes between 

 Galveston Bay and the Sabine River have migrated to the rice prairie region 

 southwest of Houston (Texas Parks and Wildlife Department 1975). Similar 

 changes have been noted in Louisiana, where geese are utilizing the rice 

 fields of southwestern Louisiana to a greater extent than they had previ- 

 ously (Louisiana Wildlife and Fisheries Commission 1961). Louisiana geese, 

 however, are generally counted in rice fields within or proximal to Louisi- 

 anan Chenier Plain boundaries, such that population fluctuation has not 

 been observed. 



Geese are more social than other waterfowl. They tend to have stronger 

 family bonds, with pair bonds lasting years in some cases, and offspring 

 remaining with parents until they become sexually mature (Smithey et al. 

 1973). 



All Chenier Plain geese exhibit similar food habits, so the following 

 discussion is intended to be relevant to other goose species. A number of 

 surveys have noted a preference for roots and tubers of marsh plants, a 

 predilection that causes large areas to be "eaten out" by flocks. As men- 

 tioned above, rice fields have become favored feeding grounds during the 

 past 20 to 30 years, especially in late winter after the close of hunting. 

 Rice stubble and unharvested or spilled grain (which accounts for 10% of 

 total planted grain) provides a supplementary food source. As browsers, 

 geese do not dabble for food to the degree that ducks do, and do not show 

 a great preference for flooded fields. 



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