Aquatic invertebrate assemblages during the spring-thaw season in wetlands of Northeastern China

Abstract

Identifying the character and importance of invertebrates in thawing wetlands is useful, since they are the main food resource for migratory waterfowl during spring. We investigated aquatic invertebrate composition in the spring-thaw and compared it with the summer in wetlands of the Sanjiang Plain, China. NMDS analysis showed that the composition of aquatic invertebrates in the spring-thaw is significantly different from in summer. Aquatic invertebrate diversity (including Shannon–Wiener index; Margalef’s species richness; Pielou’s evenness) was lower in the spring-thaw, and Network analyses indicated that it was a simpler community. Indicator species were different between spring-thaw and summer. The scraper functional feeding group (i.e., snails) dominated both seasons, but especially in the spring-thaw. Snails and other invertebrates such as asellid crustaceans abounded in spring, are rich in both calcium and protein, making them to be an especially important food source for migratory waterfowl. Therefore, the spring-thaw should be a focus when assessing aquatic invertebrate function for waterfowl production.