Organochlorine pesticide residues in pheasant eggs and waterfowl from the Texas High Plains

This study was initiated in January 1983 to gain insight into organochlorine pesticide residues present in wildlife within the Southern High Plains of Texas.

Mallards (Anas platyrhynchos) collected within the region had higher p,p'-DDE residues than reported for other areas in Texas. Adult hens had the highest residues, while juvenile hens had the lowest residues; however, these differences were not significant (P >0.05). Juvenile and adult drakes had similar DDE residues.

Blue-winged teal (Anas discors) collected in April as they migrated northward to their breeding grounds had higher (P <0.02) p,p'-DDE residues than those collected in September as they migrated southward toward their wintering areas. Juvenile teal had higher (P <0.02) DDE residues than adults, while hens had higher (P <0.003) residues than drakes. In addition to p,p'-DDE, heptachlor epoxide, endrin, o,p'-DDT, o,p'-DDD, and p,p'-DDT were detected.

Pheasant (Phasianus colchicus) eggs showed a difference in p,p'-DDE residues and eggshell thickness among four habitat types. Residues were greater (P <0.05) in eggs collected from oat fields and playa basins than those collected from alfalfa fields and wheat fields. Furthermore, eggs collected from oat fields and playa basin, were thinner (P <O.05) than those collected from wheat fields and alfalfa fields.