Helminth Assemblages of Ross’ and White-Fronted Geese Wintering in South Texas
Caesar Kleberg Wildlife Research Institute, Texas A&M University, Kingsville, TX, USA
Abstract
Helminth community structure and pattern were assessed in 16 Ross’ (Chen rossii) and 46 white-fronted geese (Anser albifrons) collected during winter 1999–2000 in Kleberg County, Texas. Infracommunities in Ross’ geese ranged from 2–6 species and 3–71 individuals, and averaged 3.6±0.3 (SE) species and 42.6±7.6 individuals. Ten species were found in the Ross’ goose component community, in which Amidostomum anseris, Epomidiostomum crami, Heterakis dispar, and Trichostrongylus tenuis were the most prevalent and dominated numerically. Amidostomum anseris, E. crami, H. dispar, T. tenuis, Tetrameres sp., and Capillaria sp. found in the Ross’ goose represent new host records. Infracommunities found in white-fronted geese ranged from 1–7 species and 4–117 individuals, and averaged 4.2±0.2 species and 28.9±4.0 individuals. Seventeen species were found in the white-fronted goose component community. Dendritobilharzia pulverulenta, Paramonostomum sp., and Capillaria sp. represent new host records in the white-fronted goose. Epomidiostomum crami, Amidostomum spatulatum, and T. tenuis were the most prevalent and dominated numerically. Rank abundance of A. spatulatum and T. tenuis varied by host age; E. crami and T. tenuis varied by host sex. Component communities between juvenile and adult white-fronted geese were most similar, followed by male and female white-fronted geese, and juvenile Ross’ and white-fronted geese. Relatively low species richness, preponderance and numeric dominance by direct-life-cycle nematodes, and absence of helminths in a number of available microhabitats suggested that the mainly herbivorous diet of Ross’ and white-fronted geese dramatically influenced helminth community structure and pattern on the wintering grounds.