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Similar to many freshwater ecosystems, the Laurentian Great Lakes of North America have undergone numerous anthropogenic stressors resulting in considerable loss of biodiversity and habitat. Among Great Lakes fishes, the coregonine sub-family has endured the most extensive declines, including extinction of several species (Coregonus johannae, C. alpenae, and C. kiyi orientalis) and at least 10 instances of local extirpations of other species (C. nigripinnis, C. reighardi, C. zenithicus, C. hoyi, and C. artedi) across all 5 lakes, much of which occurred prior to the 1960s owing to overfishing, interactions with non-indigenous species, and habitat loss. Despite these declines, no federal-, provincial-, or state-mandated actions were ever implemented to conserve coregonine diversity, potentially because so much of the coregonine declines occurred prior to the enactment of federal conservation legislation. Possible explanations for inaction since enactment of that legislation include insufficient data on biological vulnerability or threats, unresolved taxonomy, and limited support from the fishery management agencies and their stakeholders prior to the 2000s. In recent decades, however, several fishery management agencies have undertaken efforts to re-introduce coregonine diversity. These efforts helped lead to development of a science-based framework to restore coregonines that was universally endorsed by fishery managers representing eight U.S. states, four U.S. tribal organizations, and the province of ON, Canada, in May 2018. The basin-wide framework is based on principles of conservation biology and adaptive management. We describe details of its key steps, including planning, restoring, and evaluating, while also describing recent implementation efforts to develop methods, improve available resources, and enhance coordination across the basin. Although our paper describes a regional effort to restore native coregonines, our adaptive-management approach could be used by other multi-agency stakeholders seeking to conserve or restore native fishes. [ABSTRACT FROM AUTHOR]

As global fish populations face threats from climatic change and human exploitation, the value of Indigenous knowledge and technology for guiding restoration and conservation efforts is gaining increasing recognition. Indigenous fishers on the Northwest Coast of North America traditionally employed sophisticated harvesting practices developed through long-term relationships with marine ecosystems, which promoted sustained harvests. Here we examine traditional Pacific halibut (Hippoglossus stenolepis) hook technology which has been shown to reduce bycatch of nontarget species and is often described as highly size-selective. We investigate this technology using ethnographic information, analysis of fishing equipment curated in museums, and measurements of modern halibut. We identify regional variation and overlap in hook styles, expand previously established hook typologies, and observe the greatest number of hooks and the most stylistic diversity originating from Haida Gwaii, a location where available zooarchaeological data indicates high halibut abundance. We demonstrate that two measurements (hook lip-gap and barb-area size) disproportionately influence the maximum and minimum body size. Based on hook and modern fish measurements, we estimate the sample of hooks targeted fish between 53 and 145 cm in length, indicating a broad but flexible size-selectivity that has presentday relevance for fisheries conservation, including nonmortality slot-limit fishing. [ABSTRACT FROM AUTHOR]

Suckers (Catostomidae Cope, 1871) are a diverse family of freshwater fishes native to North America and East Asia. Ethnographic data indicate suckers were harvested by Indigenous peoples throughout the region and frequently of comparable importance to salmon. Suckers were taken at various times of the year through angling, netting, spearing, and other methods. Once harvested, they were, depending on local tastes and customs, consumed fresh and/ or dried. As evidenced by the existence of First Sucker Ceremonies, the taxon's presence in myths, and descriptions of suckers as being a source of spiritual powers, catostomids were also spiritually important to some Indigenous peoples. The variability in the dietary and spiritual importance, capture, and preparation of suckers that is evident in the ethnographic record underscores the dynamism of human-sucker interactions in northwestern North America. [ABSTRACT FROM AUTHOR]

The delimitation of species boundaries, particularly those obscured by reticulation, is a critical step in contemporary biodiversity assessment. It is especially relevant for conservation and management of indigenous fishes in western North America, represented herein by two species with dissimilar life histories codistributed in the highly modified Colorado River (i.e., flannelmouth sucker, Catostomus latipinnis; bluehead sucker, C. (Pantosteus) discobolus). To quantify phylogenomic patterns and examine proposed taxonomic revisions, we first employed double‐digest restriction site‐associated DNA sequencing (ddRAD), yielding 39,755 unlinked SNPs across 139 samples. These were subsequently evaluated with multiple analytical approaches and by contrasting life history data. Three phylogenetic methods and a Bayesian assignment test highlighted similar phylogenomic patterns in each, but with considerable difference in presumed times of divergence. Three lineages were detected in bluehead sucker, supporting elevation of C. (P.) virescens to species status and recognizing C. (P.) discobolus yarrowi (Zuni bluehead sucker) as a discrete entity. Admixture in the latter necessitated a reevaluation of its contemporary and historic distributions, underscoring how biodiversity identification can be confounded by complex evolutionary histories. In addition, we defined three separate flannelmouth sucker lineages as ESUs (evolutionarily significant units), given limited phenotypic and genetic differentiation, contemporary isolation, and lack of concordance (per the genealogical concordance component of the phylogenetic species concept). Introgression was diagnosed in both species, with the Little Colorado and Virgin rivers in particular. Our diagnostic methods, and the agreement of our SNPs with previous morphological, enzymatic, and mitochondrial work, allowed us to partition complex evolutionary histories into requisite components, such as isolation versus secondary contact. [ABSTRACT FROM AUTHOR]