Management practices to enhance wildlife diversity of man-made fish ponds: the importance of the hydroperiod

摘要

We examined correlates of amphibian and waterbird diversity related to management practices, with a focus on timing of flooding, at shallow ponds used for common carp Cyprinus carpio culture in Eastern Poland. The age of the stocked fish was a strong predictor of amphibian diversity, with higher scores obtained in ponds with young-of-the-year carp compared to ponds containing older (and larger) fish. Pond cover by emergent vegetation was positively related to diversity of both taxonomic groups. The timing of filling affected the taxonomic richness of the ponds; in contrast to ponds filled in early spring (March-early April), early breeding amphibian species were not recorded in ponds filled later (early May). However, amphibian diversity did not differ between early- and late-flooded ponds. Early availability of filled ponds favored waterbird species richness and diversity, and the hydroperiod effect overcame the effect of fish age/size. Dissimilar responses to hydroperiod onset may reflect differences between amphibian and bird communities in the nature and strength of interactions with fish. Timing of flooding, which appears to be a neglected determinant of biodiversity in anthropogenic wetlands, should consider the breeding and migration phenology of wildlife species and the presence and population structure of fish.