Anadromous trout from opposite sides of the globe: biology, ocean ecology, and management of anadromous brown and cutthroat trout

Abstract

Anadromous brown trout (Salmo trutta) in the northeastern Atlantic Ocean, and coastal cutthroat trout (Oncorhynchus clarkii clarkii) in the northeastern Pacific Ocean, are analogs in many ways. Both species display similar patterns of complex life histories and behavioral flexibility, are iteroparous and facultatively anadromous and occupy nearshore coastal marine habitats where numerous populations often mix. These characteristics create specific challenges for management and conservation that have been complicated by inadequate scientific attention in some areas. Both species are declining across their native range, and their ecology make them particularly vulnerable to habitat destruction, fishing, and climate change. Here, we review the available literature to compare the biology, ocean ecology, and management practices of these two species. We highlight ecological similarities and differences between the species and identify current knowledge gaps suggesting future research needs and management actions. Using a comparative approach, the review aims to promote and facilitate knowledge exchange between anadromous trout research communities from opposite sides of the globe to improve management and conservation of these species and stimulate the production of management plans specific to anadromous trout.

Leveraging the genetic diversity of trout in the rivers of the British Isles and northern France to understand the movements of sea trout (Salmo truttaL.) around the English Channel

“…More recently, populations of both trout and Atlantic salmon have been severely affected by human-related activities, including targeted estuarine net fisheries, changes to river navigability and barriers to upstream movement (weirs, dams), point-source and diffuse pollution, loss of spawning habitat and many stocking and translocation events (Losee et al, 2024; Nevoux et al, 2019). It is this combination of historic and contemporary factors that have shaped the present mosaic of genetic groupings of trout in rivers on both sides of the English Channel and in the southern North Sea (King et al, 2016; King et al, 2020; Quéméré et al, 2016).…”

Leveraging the genetic diversity of trout in the rivers of the British Isles and northern France to understand the movements of sea trout (Salmo trutta L.) around the English Channel

“…More recently, populations of both trout and Atlantic salmon have been severely affected by human‐related activities, including targeted estuarine net fisheries, changes to river navigability and barriers to upstream movement (weirs, dams), point‐source and diffuse pollution, loss of spawning habitat and many stocking and translocation events (Losee et al., 2024 ; Nevoux et al., 2019 ). This combination of historic and contemporary factors has shaped the present mosaic of genetic groupings of trout in rivers on both sides of the English Channel and in the southern North Sea (King et al., 2016 , 2020 ; Quéméré et al., 2016 ).…”