Stream animals on tropical high islands have ecological counterparts among continental fauna but are confronted with highly dynamic and variable environmental conditions that can far exceed those occurring in mainland...Stream animals on tropical high islands have ecological counterparts among continental fauna but are confronted with highly dynamic and variable environmental conditions that can far exceed those occurring in mainland streams.In response to weather fronts passing through an island chain or to localized fluctuations in the formation of orographic rain,water levels in island streams can change from low flows of a few centimeters depth to sudden flash floods of several meters and back to clear shallow water within a few days.Studies of the five species of indigenous Hawaiian stream fishes have shown that the dispersal of larvae out to sea and their return several months later during their amphidromous life cycles constantly restock streams and provide a kind of ready reserve for recolonizing streams after unusually harsh disturbances,such as the recent Hurricane Iniki.Because of the predominance of amphidromy among the major species of stream fishes and macroinvertebrates on tropical Pacific high islan s,we hypothesize that maintaining biodiversity in these island streams when conditions are otherwise favorable and restoring animal life to formerly diverted streams may be no more complicated than assuring that the freshwater-marine threshold remains open and that natural fluctuations in flow are unhampered.展开更多
基金西南财经大学2023年度“中央高校教学改革与研究”项目(220810004006000029)中央高校基本科研业务费专项资金资助(Supported by the Fundamental Research Funds for the Central Universities)(JBK23YJ24)。
文摘Stream animals on tropical high islands have ecological counterparts among continental fauna but are confronted with highly dynamic and variable environmental conditions that can far exceed those occurring in mainland streams.In response to weather fronts passing through an island chain or to localized fluctuations in the formation of orographic rain,water levels in island streams can change from low flows of a few centimeters depth to sudden flash floods of several meters and back to clear shallow water within a few days.Studies of the five species of indigenous Hawaiian stream fishes have shown that the dispersal of larvae out to sea and their return several months later during their amphidromous life cycles constantly restock streams and provide a kind of ready reserve for recolonizing streams after unusually harsh disturbances,such as the recent Hurricane Iniki.Because of the predominance of amphidromy among the major species of stream fishes and macroinvertebrates on tropical Pacific high islan s,we hypothesize that maintaining biodiversity in these island streams when conditions are otherwise favorable and restoring animal life to formerly diverted streams may be no more complicated than assuring that the freshwater-marine threshold remains open and that natural fluctuations in flow are unhampered.
