Fish communities in coastal freshwater ecosystems: the role of the physical and chemical setting

Mark B Bain,Kristin K Arend

doi:10.1186/1472-6785-8-23

Abstract

BackgroundWe explored how embayment watershed inputs, morphometry, and hydrology influence fish community structure among eight embayments located along the southeastern shoreline of Lake Ontario, New York, USA. Embayments differed in surface area and depth, varied in their connections to Lake Ontario and their watersheds, and drained watersheds representing a gradient of agricultural to forested land use.ResultsWe related various physicochemical factors, including total phosphorus load, embayment area, and submerged vegetation, to differences in fish species diversity and community relative abundance, biomass, and size structure both among and within embayments. Yellow perch (Perca flavescens) and centrarchids numerically dominated most embayment fish communities. Biomass was dominated by piscivorous fishes including brown bullhead (Ameiurus nebulosus), bowfin (Amia calva), and northern pike (Esox lucius). Phosphorus loading influenced relative biomass, but not species diversity or relative abundance. Fish relative abundance differed among embayments; within embayments, fish abundance at individual sampling stations increased significantly with submerged vegetative cover. Relative biomass differed among embayments and was positively related to total phophorus loading and embayment area. Fish community size structure, based on size spectra analysis, differed among embayments, with the frequency of smaller-bodied fishes positively related to percent vegetation.ConclusionThe importance of total phosphorus loading and vegetation in structuring fish communities has implications for anthropogenic impacts to embayment fish communities through activities such as farming and residential development, reduction of cultural eutrophication, and shoreline development and maintenance.

Highlights

We explored how embayment watershed inputs, morphometry, and hydrology influence fish community structure among eight embayments located along the southeastern shoreline of Lake Ontario, New York, USA
Fish community structure Across all embayments, we collected a total of 3475 fishes representing 42 different species and 16 families
Our findings suggest that fish communities are structured by factors operating at multiple spatial scales and on multiple community characteristics

Summary

Introduction

We explored how embayment watershed inputs, morphometry, and hydrology influence fish community structure among eight embayments located along the southeastern shoreline of Lake Ontario, New York, USA. Embayments serve as conduits of nutrients and other materials from their watersheds [12,13], support high fish species diversity [12], provide spawning and nursery habitats for both nearshore and offshore Great Lakes fishes [14,3,15], and are concentrated areas of human activities [16]. These characteristics make embayments ideal systems with which to address physicochemical effects on fish community structure in the context of ecosystem function

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Results

Discussion

Conclusion