Center for Systems Integration and Sustainability

Journal or Book Title: American Fisheries Society Symposium

Volume/Issue: 21

Page Number(s): 112-123

Year Published: 1998

A lethal thiamine deficiency afflicting larval land locked Atlantic salmon Salmo salar in several of New York's Finger Lakes has heen linked lo a maternal diet of the exotic, thiaminase-rich alewife Alosa pseudoharengus. To evaluate why trout and char species in the Finger Lakes are appar­ently not affected by this "Cayuga syndrome," levels of thiamine in the whole blood of syndrome­ positive and syndrome-negative stocks of Atlantic salmon were compared with levels in lake trout Salvelinus namaycush, brown trout Salmo trutta , and rainbow trout Oncorhynchus mykiss from Ca­yuga and/or Seneca lakes. Thiamine levels did not differ between sexes within any species or stock. Consistent with the hypothesis that thermal habitat partitioning may predispose the salmon to more dietary thiaminase than other Finger Lakes salmonids, thiamine levels in the salmon that produced syndrome-positive sac fry were significantly lower than levels measured in Finger Lakes brown trout and rainbow trout. In contrast, there was no difference between the syndrome-positive salmon and Finger Lakes lake trout, possibly because the male char were in starved (postspawned) condition. Regressions of maternal blood or egg thiamine versus maternal weight and length were not significant for salmon that produced syndrome-positive sac fry; yet, a significant inverse relationship was detected for the syndrome-negative salmon from the Adirondack progenitor stock. These findings may reflect the transition of these reference control salmon from a thiaminase-poor invertebrate diet to a piscivo­rous diet of thiaminase-active smelt Osmerus mordax.

Type of Publication: Meeting/Symposia/Seminar/Workshop Proceedings