Conservation of Native Stream Gobies in the Hawaiian Archipelago

Photo: J. Derek Hogan

Gobies are prominent members of stream fish communities on tropical islands around the world. Many species of these small fish have evolved from marine ancestors, taking advantage of the opportunities afforded by island streams. However, they retain an obligate marine larval phase, giving rise to a complex life history strategy in which hatching, growth, and breeding all occur in streams but the tiny larvae can disperse among islands (i.e., amphidromy). It is unknown whether populations on different islands have diverged, or instead the species are functionally panmictic. As streams on tropical islands around the globe are becoming increasingly degraded, numerous species of stream gobies are at risk of extinction. In collaboration with Mike Blum and Jim Gilliam, and supported by SERDP, we are analyzing the population structure, demography, and landscape influences upon goby species throughout the Hawaiian archipelago. My group's role in the project is to use trace element fingerprinting in goby otoliths to understand their dispersal strategies and track individual movement between and within islands. We also lead the analysis of stream water quality to assess the effects of land use.

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