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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]

Nitellopsis obtusa (Desv.) J. Groves (starry stonewort) is a macroalga in the Characeae family first documented in North America c. 1974. Since initial introduction, N. obtusa clonal populations quickly established in inland lakes as early as 2005. Despite increased N. obtusa monitoring over the last decade, only sterile or male specimens were documented in North America; however, during routine monitoring in Lake Simcoe and Lake Scugog in 2022, we discovered the presence of female gametangia on N. obtusa. In addition, two other Characeae genera had prevalent antheridia and oogonia, co-occurring with oogonia-presenting N. obtusa, which had not been observed previously despite intensive monitoring since 2008. Further studies in North America are required to confirm the proportion of female populations present within invaded regions, as well as to identify plausible causes shifting gametangia development across non-native and native Characeae, especially within the context of climate change. The presence of oogonia on N. obtusa represents a major change to our understanding of this species and its reproductive ecology in North America. [ABSTRACT FROM AUTHOR]