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Full-Text Articles in Life Sciences
Shortnose Sturgeon (Acipenser Brevirostrum) Spawning Potential In The Penobscot River, Maine: Considering Dam Removals And Emerging Threats, Catherine Johnston
Shortnose Sturgeon (Acipenser Brevirostrum) Spawning Potential In The Penobscot River, Maine: Considering Dam Removals And Emerging Threats, Catherine Johnston
Electronic Theses and Dissertations
Dam removals from the Penobscot River in Maine restored access to freshwater habitat critical for the life cycle of endangered shortnose sturgeon. Prior to the dam removals, shortnose sturgeon spawning activity had not been documented. Instead, evidence suggested that individuals emigrated from the Penobscot River to spawn in the Kennebec complex, 140 km away. A central question of this thesis was whether spawning activity would commence in the first two years following dam removal. Consistent with pre-dam removal movement patterns determined using acoustic telemetry, the majority (78%) of tagged individuals emigrated from the Penobscot River at some point over the …
Exploring The Threats Of Dams And Ocean Conditions: In-River Movements And Ocean Growth Of Atlantic Salmon (Salmo Salar) From Maine's Rivers, Lisa K. Izzo
Electronic Theses and Dissertations
Substantial declines of anadromous Atlantic Salmon Salmo salar have occurred throughout the range of the species, with many populations at the southern extent of the distribution being extirpated or endangered. While Maine is the last state in the country where adult Atlantic Salmon return to rivers each year to spawn, numbers have decreased dramatically in recent decades, with typically less than 2,000 spawners returning to all Maine's rivers combined. The complex life history of this species, which involves a juvenile freshwater phase followed by a marine phase that can last one to five years before returning to freshwater to spawn …
Assessment Of A Hatchery Based Rainbow Smelt Supplementation Effort, Andrew O'Malley
Assessment Of A Hatchery Based Rainbow Smelt Supplementation Effort, Andrew O'Malley
Electronic Theses and Dissertations
Rainbow Smelt (Osmerus mordax) are an important fish distributed throughout northeastern North America with both anadromous and landlocked populations. Abundance, size at age, and maximum size vary widely among populations and life histories. In order to compare anadromous and landlocked populations, we collected spawning adults in 2014 from four anadromous and three landlocked populations. Scales and otoliths from the anadromous fish were examined and compared for estimates of bias and precision in ageing. Analysis of both scales and otoliths provided age estimates that were acceptable, but estimates from scales were more precise and had less bias. Otoliths were …