The University of Toledo

GLGL Neogobiin Research

The objectives of goby research at Dr. Carol Stepien's Great Lakes Genetics Laboratory are to elucidate the evolutionary history, species identifications, and biogeographic diversification patterns of the "neogobiin" gobies in Eurasia and North America.  The results of this ongoing investigation have been published in a variety of peer reviewed journals.

The "neogobiin" gobies are a remarkable endemic “species flock” of Ponto-Caspian fishes (native to the Black and Caspian Seas, and belonging to one of the largest families of fishes) that have become a growing problem in their invasions of North American and Eurasian ecosystems.  Many ecologists believe that such introductions of exotic species pose one of the most serious threats to native ecosystems worldwide.  For example, the ecology of the North American Great Lakes has been restructured by waves of invaders that were accidentally introduced from ships’ ballast water, including the Ponto-Caspian round goby and its zebra mussel prey.  Two "neogobiin" species – the round goby Neogobius melanostomus and the tubenose goby Proterorhinus semilunaris – invaded the North American Great Lakes in the early 1990s and the former spread rapidly to all five Great Lakes.

"Neogobiin" research at the Great Lakes Genetics Laboratory utilizes the powerful tools of modern genetic analysis to explore the evolutionary history, species identifications, and biogeographic diversification patterns of these fishes.  Systematic research is clearing up the confused genealogy and taxonomy of this poorly understood group.  It has also revealed cryptic species within the genus Proterorhinus, improving our ability to genetically distinguish these fishes.  Population genetic work has concentrated on understanding the biogeography of species that are expanding their ranges into new areas.  To date, work has been done on the racer goby Babka gymnotrachelus in Eurasia, and on the tubenose goby genus Proterorhinus and the round goby Neogobius melanostomus in Eurasia and North America.  Work on the round goby populations from both continents has led to the identification of at least one source population from the mouth of the Dnieper River, in the northwestern portion of the Black Sea.  In addition, parasitological comparison of round and tubenose gobies from Eurasia and North America revealed that the introduced fishes had lower parasite numbers and had escaped specialized parasites from their native range.