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The bridle shiner (Notropis bifrenatus) is a small cyprinid native to the eastern United States and Canada. Bridle shiner populations have declined across their range, and the species now receives concern status or legal protection in 13 states and two provinces. Bridle shiners were historically found in southern and western Maine in densely vegetated, shallow habitats along the shorelines of streams and ponds. We surveyed areas of Maine that supported historical bridle shiner populations using environmental DNA (eDNA) and traditional seine netting methods, and then used eDNA sampling to survey areas with unknown bridle shiner presence. We rediscovered bridle shiner populations at 11 of 32 historically occupied waterbodies and documented bridle shiners in four additional waterbodies. We determined that both eDNA and seine net surveys are viable options for monitoring bridle shiners in Maine and identified ways to streamline the eDNA methods used in this study to reduce the time and cost of future surveys. [ABSTRACT FROM AUTHOR]

Two categories of evolutionary challenges result from escalating human impacts on the planet. The first arises from cancers, pathogens, and pests that evolve too quickly and the second, from the inability of many valued species to adapt quickly enough. Applied evolutionary biology provides a suite of strategies to address these global challenges that threaten human health, food security, and biodiversity. This Review highlights both progress and gaps in genetic, developmental, and environmental manipulations across the life sciences that either target the rate and direction of evolution or reduce the mismatch between organisms and human-altered environments. Increased development and application of these underused tools will be vital in meeting current and future targets for sustainable development.

Evolutionary principles are now routinely incorporated into medicine and agriculture. Examples include the design of treatments that slow the evolution of resistance by weeds, pests, and pathogens, and the design of breeding programs that maximize crop yield or quality. Evolutionary principles are also increasingly incorporated into conservation biology, natural resource management, and environmental science. Examples include the protection of small and isolated populations from inbreeding depression, the identification of key traits involved in adaptation to climate change, the design of harvesting regimes that minimize unwanted life-history evolution, and the setting of conservation priorities based on populations, species, or communities that harbor the greatest evolutionary diversity and potential. The adoption of evolutionary principles has proceeded somewhat independently in these different fields, even though the underlying fundamental concepts are the same. We explore these fundamental concepts under four main themes: variation, selection, connectivity, and eco-evolutionary dynamics. Within each theme, we present several key evolutionary principles and illustrate their use in addressing applied problems. We hope that the resulting primer of evolutionary concepts and their practical utility helps to advance a unified multidisciplinary field of applied evolutionary biology.

Movement of shortnose sturgeon (Acipenser brevirostrum) among major river systems in the Gulf of Maine is common and has implications for the management of this endangered species. Directed movements of 61 telemetered individuals monitored between 2010 and 2013 were associated with the river of tagging and individual characteristics. While a small proportion of fish tagged in the Kennebec River moved to the Penobscot River (5%), a much higher proportion of fish tagged in the Penobscot River moved to the Kennebec River (66%), during probable spawning windows. This suggests that Penobscot River fish derive from a migratory contingent within a larger Kennebec River population. Despite this connectivity, fish captured in the Penobscot River were larger (~100 mm fork length) and had higher condition factors (median Fulton's K: 0.76) than those captured in the Kennebec River (median Fulton's K: 0.61). Increased abundance and resource limitation in the Kennebec River may be constraining growth and promoting migration to the Penobscot River by individuals with sufficient initial size and condition. Migrants could experience an adaptive reproductive advantage relative to nonmigratory individuals. Les deplacements d'esturgeons a museau court (Acipenser brevirostrum) entre les grands reseaux hydrographiques du golfe du Maine sont repandus et ont des repercussions sur la gestion de cette espece en voie de disparition. Les deplacements diriges de 61 individus dotes d'etiquettes telemetriques suivis de 2010 a 2013 ont ete associes au fleuve oU a eu lieu l'etiquetage et a des caracteristiques individuelles. Si une petite proportion des poissons etiquetes dans le fleuve Kennebec est passee au fleuve Penobscot (5 %), une proportion beaucoup plus importante de poissons etiquetes dans le fleuve Penobscot est passee dans le fleuve Kennebec (66 %) durant de vraisemblables fenetres de frai. Cela donne a penser que les poissons du fleuve Penobscot sont issus d'un contingent migrateur d'une plus grande population du fleuve Kennebec. Malgre cette connectivite, les poissons pris dans le fleuve Penobscot etaient plus grands (longueur a la fourche : ~100 mm) et presentaient des facteurs d'embonpoint plus eleves (K de Fulton median : 0,76) que les poissons captures dans le fleuve Kennebec (K de Fulton median : 0,61). Une abondance accrue et la limitation des ressources dans le fleuve Kennebec pourraient restreindre la croissance et promouvoir la migration vers le fleuve Penobscot d'individus de taille et d'embonpoint initiaux suffisants. Les migrants pourraient en tirer un avantage adaptatif sur le plan de la reproduction par rapport aux individus non migrateurs. [Traduit par la Redaction], Introduction Migratory behaviors displayed by fishes facilitate the tracking and use of transient resources over a lifetime (Dingle and Drake 2007). In many cases, migratory behaviors vary widely among individuals [...]

We developed a hierarchical multistate model to estimate survival of Atlantic salmon (Salmo salar) smolts in the Penobscot River, USA, over a decade during which two mainstem dams were removed from the catchment. We investigated effects of (i) environmental factors, (ii) rearing history, and (iii) management actions, including dam removal, turbine shutdown, and installation of new powerhouses. Mean ± SD smolt survival per kilometre was higher through free-flowing reaches of the catchment (0.995 [+ or -] 0.004 x [km.sup.-1]) than through reaches containing dams that remain in the system (0.970 ± 0.019-[km.sup.-1]). We observed maximum survival between 12 and 17°C and at intermediate discharges (1200 [m.sup.3] x [s.sup.-1]). Smolt survival increased concurrent with dam removal and decreased following increases in hydropower generation. The greatest increase in smolt survival followed seasonal turbine shutdowns at a dam located on the largest tributary to the Penobscot River, while other shutdowns had little influence. Our model provides a useful tool for assessing changes to survival of migratory species and will be useful for informing stocking plans to maximize numbers of smolts leaving coastal systems. Nous avons elabore un modele multi-etats hierarchique pour estimer la survie de saumoneaux de saumon atlantique (Salmo salar) dans le fleuve Penobscot (Etats-Unis) pendant une decennie durant laquelle deux barrages sur le bras principal du fleuve ont ete retires du bassin versant. Nous avons examine les effets (i) de facteurs ambiants, (ii) de l'historique d'elevage et (iii) des mesures de gestion dont le retrait de barrages, l'arret de turbines et l'amenagement de nouvelles centrales electriques. Le taux de survie moyen ± ecart-type par kilometre des saumoneaux etait plus eleve dans les troncons non regules du bassin versant (0,995 ± 0,004 x [km.sup.-1]) que dans les troncons contenant toujours des barrages (0,970 ± 0,019 x [km.sup.-1]). Les taux de survie maximums observes etaient entre 12 et 17°C et a des debits intermediaires (1200 [m.sup.3] x [s.sup.-1]). La survie des saumoneaux a augmente apres le retrait des barrages et diminue apres des augmentations de la production hydroelectrique. La plus grande augmentation du taux de survie des saumoneaux coincidait avec des arrets saisonniers de turbines a un barrage sur le plus grand affluent du fleuve Penobscot, alors que les autres arrets de turbines n'ont pas eu une grande influence. Notre modele constitue un outil pour evaluer les variations de la survie d'especes migratrices et pour eclairer l'elaboration de plans d'empoissonnement dans le but de maximiser le nombre de saumoneaux qui quittent les systemes cotiers. [Traduit par la Redaction], Introduction Atlantic salmon (Salmo salar) stocks in North America diminished beginning in the 1800s, owing to pollution, poor land-use practices, dams, and overfishing (Haines 1992; Parrish et al. 1998). Many [...]

Timing of ocean entry is critical for marine survival of both hatchery and wild Atlantic salmon (Salmo salar) smolts. Management practices and barriers to migration such as dams may constrain timing of smolt migrations resulting in suboptimal performance at saltwater entry. We modeled influences of stocking location, smolt development, and environmental conditions on (i) initiation of migration by hatchery-reared smolts and (ii) movement rate of hatchery- and wild-reared Atlantic salmon smolts in the Penobscot River, Maine, USA, from 2005 through 2014 using acoustic telemetry data. We also compared movement rates in freeflowing reaches with rates in reaches with hydropower dams and head ponds. We compared movement rates before and after (1) removal of two mainstem dams and (2) construction of new powerhouses. Initiation of movement by hatchery fish was influenced by smolt development, stocking location, and environmental conditions. Smolts with the greatest gill [Na.sup.+], [K.sup.+]-ATPase (NKA) activity initiated migration 24 h sooner than fish with the lowest gill NKA activity. Fish with the greatest cumulative thermal experience initiated migration 5 days earlier than those with lowest cumulative thermal experience. Smolts released furthest from the ocean initiated migration earlier than those released downstream, but movement rate increased by fivefold closer to the ocean, indicating behavioral trade-offs between initiation and movement rate. Dams had a strong effect on movement rate. Movement rate increased from 2.8 to 5.4 km x [h.sup.-1] in reaches where dams were removed, but decreased from 2.1 to 0.1 km x [h.sup.-1] in reaches where new powerhouses were constructed. Movement rate varied throughout the migratory period and was inversely related to temperature. Fish moved slower at extreme high or low discharge. Responses in fish movement rates to dam removal indicate the potential scope of recovery for these activities. Le moment de l'entree en mer joue un role cle dans la survie en mer des saumoneaux de saumon atlantique (Salmo salar) tant sauvages qu'issus d'ecloseries. Les pratiques de gestion et obstacles a la migration, tels que les barrages, peuvent restreindre le moment de la migration des saumoneaux, entrainant une performance moins qu'optimale a l'entree en eau salee. Nous avons modelise les influences du lieu d'empoissonnement, du developpement des saumoneaux et des conditions ambiantes sur (i) le debut de la migration par les saumoneaux eleves en ecloseries et (ii) la vitesse des deplacements de saumoneaux eleves en ecloseries et a l'etat sauvage dans le fleuve Penobscot (Maine, Etats-Unis), de 2005 a 2014, a la lumiere de donnees de telemetrie acoustique. Nous avons egalement compare les vitesses de deplacement dans des troncons non regules et des troncons contenant des barrages hydroelectriques et des reservoirs de barrage. Nous avons compare les vitesses de deplacement avant et apres (1) le retrait de deux barrages sur le bras principal et (2) la construction de nouvelles centrales electriques. Le debut des deplacements par les poissons issus d'ecloseries etait influence par le developpement des saumoneaux, le lieu d'empoissonnement et les conditions ambiantes. Les saumoneaux presentant la plus forte activite de la [Na.sup.+], [K.sup.+]-ATPase (NKA) dans les branchies commencaient leur migration 24 heures plus tot que les poissons avec la plus faible activite de la NKA dans les branchies. Les poissons caracterises par la plus importante experience thermique cumulative commencaient a migrer 5 jours plus tot que ceux avec la plus faible experience thermique cumulative. Les saumoneaux relaches le plus loin de l'ocean commencaient a migrer plus tot que ceux relaches plus en aval, mais la vitesse de deplacement quintuplait plus pres de l'ocean, indiquant des compromis comportementaux entre l'initiation et la vitesse des deplacements. Les barrages exercaient une forte influence sur la vitesse de deplacement, cette derniere augmentant de 2,8 a 5,4 km x [h.sup.-1] dans les troncons dont des barrages ont ete retires, mais diminuant de 2,1 a 0,1 km x [h.sup.-1] dans les troncons ou de nouvelles centrales electriques ont ete construites. La vitesse de deplacement variait tout au long de la periode de migration et etait inversement reliee a la temperature. Les poissons se deplacaient plus lentement a debits extremes forts ou faibles. Les reactions au retrait de barrages refletees dans les vitesses de deplacement des poissons indiquent l'ampleur potentielle du retablissement associee a ces activites. [Traduit par la Redaction], Introduction Seaward migration through freshwater and estuarine habitats to ocean feeding grounds represents a critical transition in the life history of anadromous fishes (Zydlewski and Wilkie 2013). In Atlantic salmon [...]