The sea otter has experienced a dramatic population decline caused by intense human harvesting, followed by a century of recovery including relocation efforts to reestablish the species across its former range in the eastern Pacific. Although the otter was historically present along the coast in Oregon, there are currently no populations in this region and reintroduction efforts have failed. We examined the mtDNA genotypes of 16 pre-harvest otter samples from two Oregon locations in an attempt to determine the best genotypic match with extant populations. Our amplifications of a 222 base-pair portion of the control region from otters ranging in age from approximately 175-2000 years revealed four genotypes. The genotypic composition of pre-harvest otter populations appears to match best with those of contemporary populations from California and not from Alaska, where reintroduction stocks are typically derived.

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Nondestructive, sublethal, and sensitive health monitoring tools are needed to assess the health of freshwater mussels (family Unionidae). Recent developments to standardize hemocyte characterization have assisted in the hematologic assessment of wild and captive freshwater mussels. In this study, preliminary baseline hematological reference ranges were established for wild mapleleaf mussels Quadrula quadrula (n = 14) and threeridge mussels Amblema plicata (n = 20) collected from the Muskingum River in Devola, Ohio. Mussels were collected from the wild, and hemolymph was sampled from each mussel in the field upon capture (baseline sample). They were then transported live to a propagation facility. Subsequent hemolymph samples were collected at 2 and 4 weeks and quarterly thereafter for 11 months following translocation. Hemocyte counts, hemocyte morphology, and hemolymph chemistry (Na , Cl , Mg , P , K , Ca , glucose, alanine aminotransferase, aspartate aminotransferase, and alkaline phosphatase]) were measured from each sample on each sampling occasion. Hemocyte counts were consistently greater in Q. quadrula than in A. plicata following transfer to captivity. Baseline hemocyte morphology and hemolymph chemistry varied between species. This study provides a foundation of reference ranges for hemocyte characterization for Q. quadrula, and A. plicata and a preliminary understanding of how hemocyte character might be expected to change when wild mussels are translocated into captivity, and thus be a useful technique for monitoring the health of freshwater mussels.