Interactions Among Waterfowl, Fishes, Invertebrates, and Macrophytes in Four Maine Lakes of Different Acidity

摘要

The study addresses the influence of low pH waters on community structure and species interactions on two pairs of oligotrophic, headwater ponds that were physically similar but with markedly different acidities. The circumneutral ponds had fish and the acidic ponds were fishless. The results showed macrophyte species was lower in the acidic ponds possibly due to low pH. Although macroinvertebrate species differed between acidic and circumneutral ponds, Diptera were the most abundant macroinvertebrates on both sets of ponds. Diptera were the principle item in the diet of brook trout in the circumneutral ponds. Because of the absence of fish in the acidic ponds, the study suggests that a potential competitor of ducks for aquatic foods had been eliminated.