Several nature-like fishway designs have been constructed in the northeastern US, but none of these fishways have been quantitatively evaluated for passage of northeastern diadromous species. This report summarizes data on passage performance from two studies of nature-like fishway designs for passage of river herring in the field (Town Brook, Plymouth, Massachusetts, and East River, Guilford, ...

Geochemical signatures in the otoliths of diadromous fishes may allow for retrospective analyses of natal origins. In an assessment of river-specific signatures in American shad (Alosa sapidissima), an anadromous clupeid native to the Atlantic coast of North America, stable isotope and elemental ratios in otoliths of juvenile American shad produced accurate natal tags from 12 rivers. Significan...

Juvenile American shad Alosa sapidissima were subjected to isothermal transfers into sea water (salinity 24) ‘early’ (1 September; 24 C) and ‘late’ (10 November; 10 C) in the autumn migratory season. Early acclimation resulted in a modest osmotic perturbation that recovered rapidly. Haematocrit declined by 14% at 24 h, recovering within 48 h. Plasma osmolality increased by 6% at 4 h, recovering...

Anadromous alewives, Alosa pseudoharengus, have experienced significant population level declines caused by factors including habitat destruction. Alewives occur in two different life histories, anadromous and landlocked forms. The landlocked alewife evolved from ancestral anadromous populations, resulting in an exclusively freshwater and phenotypically unique form. The occurrence of parasites ...

Over the past five decades, a reproductive failure related to thiamine deficiency, referred to as thiamine deficiency complex (TDC), has been observed in valuable salmonine fishes in the Great Lakes and Finger Lakes in North America and the Baltic Sea in Europe. The cause of TDC has been linked to the consumption of clupeid fish, which contain high levels of a thiamine-destroying enzyme called ...