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Filters: Tags: {"scheme":"Geographic Names Information System (GNIS)"} (X) > partyWithName: Nathan A Johnson (X)

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Freshwater mussels (Unionidae) are among the most imperiled groups of organisms in the world. Unionids are plagued with a lack of basic information regarding species distributions, life history characteristics, and ecological and biological requirements. We assessed the influence of hydrologic factors on the occurrence of the Suwannee Moccasinshell, Medionidus walkeri, a federally threatened freshwater mussel species endemic to the Suwannee River basin in Georgia and Florida. We also assessed the influence of survey effort on detection of M. walkeri during field surveys. All current (2013-2016) mussel survey records in the Suwannee River Basin were compiled, and cumulative discharge contributed by upstream springs...
Conservation of imperiled species is frequently challenged by insufficient knowledge of life history and the environmental factors that affect various life stages. The larvae (glochidia) of most freshwater mussels in the family Unionidae are obligate ectoparasites of fishes. We describe the early life history of the federally endangered Southern Kidneyshell, Ptychobranchus jonesi, and compare methods for estimating fecundity and conducting host trials on conglutinate-producing mussel species. Both the glochidial inoculation baths and direct feeding of conglutinates to Percina nigrofasciata, Etheostoma edwini, and Etheostoma fusiforme resulted in successful metamorphosis to the juvenile life stage. Ptychobranchus...