Climate change and conservation of endemic amphidromous fishes in Hawaiian streams

Abstract

Amphidromous fishes are important members of oceanic island freshwater commu-nities. Although often depauperate, amphidromous fish assemblages on islands are largely com-posed of endemic species. Little is known about the effects of anthropogenic stressors on amphi -dromous fishes, and the consequences of climate-driven changes in water quality and quantity areparticularly uncertain. Focusing on native fishes in Hawaii, we discuss the potential for climatechange to intensify 3 major threats facing amphidromous fish: (1) loss of 'ridge-to-reef' migratorycorridors via disruption of surface water connectivity, (2) in-stream habitat degradation and (3)exotic species introductions. Successfully addressing these and other threats to native fish inHawaii will require approaches that balance conservation needs with use of water resources.Conservation initiatives should focus on 'scaling up' ongoing projects intended to demonstratehow stream protection and restoration, non-native species removal and reintroductions can bene-fit at-risk species. Research initiatives should focus on determining the ecological controls onrecruitment under current and future climate conditions.