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SERVAL IUCN Conservation Status: Least Concern LIFESPAN 10 years average in the wild LENGTH 67-100 centimeters 26-39 inches (not including tail) WEIGHT 9-18 kilograms 20-40 pounds Servals require a territory [...]

The only population of the endangered blue racer (Coluber constrictor foxii) in Canada occurs on Pelee Island, Ontario. The species is threatened by multiple factors, including habitat degradation and loss, road mortality, persecution, and potentially predation. We designed and evaluated the performance of an environmental DNA droplet digital PCR assay that can be used for multiple facets of conservation of this species. We tested the assay in silico and in vitro using DNA of blue racers and co-occurring snake species and estimated the LOD and LOQ using synthetic DNA. As wild turkey predation has been suggested to negatively afect racers, we tested the assay on eight wild turkey faecal samples. Our assay is specific, can detect the target species at very low levels of concentration (0.002 copies/[micro]L), and can accurately quantify copy numbers [greater than or equal to] 0.26 copies/[micro]L. We detected no racer DNA in any wild turkey faecal sample. More faecal samples collected at strategic locations during snake peak activity on Pelee Island would enable a more thorough assessment of the possibility of turkey predation. Our assay should be effective for other environmental samples and can be used for investigating other factors negatively affecting blue racers, for example, helping to quantify blue racer habitat suitability and site occupancy. Key words: environmental DNA, reptile, conservation, droplet digital PCR, Introduction The blue racer (Coluber constrictor foxii (Baird and Girard, 1853)) is a large, non-venomous subspecies of the eastern racer, with a limited distribution in North America. It occurs in [...]

Anthropogenic climate change is warming global temperatures, with significant implications for salmonid fishes that depend on the availability of cold water during one or more life stages. Along the southern range extents of many species, and elsewhere that warm temperatures are increasingly problematic, identification and protection or restoration of habitats that may serve as climate refugia where local populations can persist is emerging as an important conservation tactic. In this perspective piece, we address the concept and utility of climate refugia--drawing a distinction with the more commonly considered thermal refuges--describe technological advances that enable accurate temperature mapping and species distribution modeling in lotic environments, and outline key uncertainties and opportunities to chart a constructive path forward on a topic that will continue to grow in importance. Identifying climate refugia is not a panacea for salmonid conservation, but we argue that there are tangible benefits to doing so, not the least of which are the options it affords for thinking and acting strategically within the context of a changing climate this century. Key words: stream, climate change, climate refugia, thermal refuge, salmonid, species distribution model, Introduction Salmon, trout, char, lenok, whitefish, and taimen in the family Salmonidae (hereafter, salmonids) are commonly and often interchangeably referred to as cold-water fishes due to the temperatures of their [...]

Translational ecology defines a collaborative effort among scientists and stakeholders to rapidly translate environmental problems into action. This approach can be applied in a fisheries management context when information needed to inform regulations is unavailable, yet conservation concerns exist. Our research uses a translational ecology framework to assess the stock status and develop research priorities for the crevalle jack (Caranx hippos) in the Florida Keys, USA, a currently unregulated species. Interview data that compiled expert fishing guide knowledge were used to develop hypotheses tested using existing fisheries-dependent datasets to check for agreement among sources and assess the consistency of observed patterns. Six hypotheses were developed concerning the status and trends of the crevalle jack population in the Florida Keys, and four of these hypotheses received clear support, with agreement between guide observations and one or more of the fisheries-dependent datasets. The results of our study outline an effective translational ecology approach for recreational fisheries management designed to rapidly recognize potential management needs as identified by fishing guides, which allows for actionable science and proactive management. L'ecologie traductionnelle designe les efforts de collaboration de chercheurs et de parties prenantes visant a traduire rapidement des problemes environnementaux en gestes concrets. Cette approche peut etre appliquee dans un contexte de gestion des peches quand l'information necessaire a l'elaboration de reglements n'est pas disponible, mais qu'il existe des situations preoccupantes. Nos travaux font appel a un cadre d'ecologie traductionnelle pour evaluer l'etat du stock et etablir des priorites de recherche pour une espece actuellement visee par aucune reglementation, la carangue crevalle (Caranx hippos), dans les Keys de la Floride (Etats-Unis). Des donnees d'interviews recensant les connaissances de guides de peche chevronnes sont utilisees pour formuler des hypotheses testees a l'aide d'ensembles existants de donnees dependantes de la peche pour verifier la concordance de differentes sources et evaluer la coherence des motifs observes. Six hypotheses sont formulees concernant l'etat et les tendances de la population de carangues crevalles dans les Keys de la Floride, et l'analyse appuie clairement quatre de ces hypotheses, pour lesquelles les observations des guides et un ou plusieurs des ensembles de donnees dependantes de la peche concordent. Les resultats de l'etude delimitent une approche efficace d'ecologie traductionnelle pour la gestion des peches sportives, conque pour faire rapidement ressortir les besoins potentiels de gestion cernes par les guides de peche et permettant du coup des applications pratiques de resultats scientifiques et une gestion proactive. [Traduit par la Redaction], Introduction In today's world of anthropogenic global change and urgent ecological crises, clear pathways for actionable science are more important than ever (Chapin 2017). Translational ecology (TE) is a developing [...]

Although he was studying brown lemurs at the time, Ian Colquhoun took the advice of his graduate advisor and switched to black lemurs, because a nearby zoo had a population [...]

Aquatic biota often face multiple anthropogenic threats such as river fragmentation and climate change that can contribute to high rates of aquatic species imperilment world-wide. Temperature- induced hypoxia is one under-explored mechanism that can threaten aquatic species in fragmented rivers with reduced flows. We applied ecosystem metabolism models to define the effect of water temperature on net ecosystem production (NEP) of oxygen at 12 sites of a fragmented river channel that supports three fish species at risk and experiences hypoxia. We found that water temperature and precipitation events at 75% of our sites were significantly and negatively correlated to NEP estimates and explained 28% of the variation in NEP within sites. Temperature-induced reductions in NEP at these sites likely contributed to hypoxic conditions threatening the three species at risk as NEP explained 41% of the variation in dissolved oxygen near all sites. Our results have applications for understanding drivers of hypoxic stress in fragmented watercourses, integrating water temperature-NEP effects with oxygen demands of sensitive fish species, and modeling future effects of climate change on aquatic species. Les organismes aquatiques font souvent face a de multiples menaces d'origine humaine telles que la fragmentation des rivieres et les changements climatiques qui peuvent contribuer a accelerer les risques pour les especes aquatiques partout sur terre. L'hypoxie induite par la temperature est un mecanisme sous- explore qui peut menacer les especes aquatiques dans les rivieres fragmentees presentant des debits reduits. Nous utilisons des modeles de metabolisme ecosystemique pour determiner l'effet de la temperature de l'eau sur la production ecosystemique nette (PEN) d'oxygene en 12 sites du chenal d'une riviere fragmentee qui soutient trois especes de poissons en peril et dans laquelle des conditions hypoxiques sont observees. Nous constatons que la temperature de l'eau et les episodes de precipitations dans 75 % des sites etudies presentent des correlations negatives significatives avec la PEN estimee et expliquent 28 % des variations de la PEN a l'interieur des sites. Les baisses de PEN induites par la temperature dans ces sites participent probablement aux conditions hypoxiques qui menacent les trois especes en peril, puisque la PEN explique 41 % des variations des teneurs d'oxygene dissous a proximite de tous les sites. Nos resultats sont importants pour la comprehension des moteurs du stress hypoxique dans les cours d'eau fragmentes, l'integration des effets de la temperature de l'eau sur la PEN aux besoins en oxygene d'especes de poissons sensibles et la modelisation des effets futurs des changements climatiques sur les especes aquatiques. [Traduit par la Redaction], Introduction Ecosystem fragmentation and reduced river flow are widespread anthropogenic impacts that threaten aquatic biodiversity globally. Dynesius and Nilsson (1994) estimated that 77% of the total discharge from large rivers [...]

Axis deer (Axis axis) are invasive species that threaten native ecosystems and agriculture on Maui Island. To mitigate negative effects, it is necessary to understand current abundance, population trajectory, and how to most effectively reduce the population. Our objectives were to examine the population history of Maui axis deer, estimate observed population growth, and use species-specific demographic parameters in a VORTEX population viability analysis to examine removal scenarios that would most effectively reduce the population. Only nine deer were introduced in 1959, but recent estimates of >10,000 deer suggest population growth rates (r) ranging between 0.147 and 0.160 even though > 11,200 have been removed by hunters and resource managers. In VORTEX simulations, we evaluated an initial population size of 6,000 females and 4,000 males, reflecting the probable 3F:2M sex ratio, with annual removal rates of 10%, 20%, and 30% over a 10-year period. A removal rate of 10% resulted in a positive growth rate of 0.103 [+ or -] 0.001. A 20% removal rate resulted in only a slightly negative growth, while a 30% removal rate resulted in -0.130 [+ or -] 0.004. By increasing the ratio of females removed to 4F:1M in the 30% harvest scenario, the decline nearly doubled, resulting in -0.223 [+ or -] 0.004. Effectively reducing axis deer will most likely require an annual removal of approximately 20-30% of the population and with a greater proportion of females to increase the population decline. Selective removal of males may not only be inefficient, but also counterproductive to population reduction goals. Keywords: Axis axis, axis deer, Hawai'i, invasive species, Maui, population modeling, HERBIVOROUS MAMMALS HAVE BEEN introduced on oceanic islands throughout the world, often with devastating consequences for native biota (Coblentz 1978, Courchamp et al. 2003). The adverse ecological effects of non-native [...]

Effective conservation requires that species recovery measures are informed by rigorous scientific research. For imperilled freshwater fishes and mussels in Canada, numerous research gaps exist, in part owing to the need for specialized research methods. The Canadian Freshwater Species at Risk Research Network (SARNET) was formed and identified or implemented approaches to address current research gaps, including (1) captive experimental research populations, (2) nonlethal methods for estimating abundance and distribution, (3) nonlethal field methods to measure life-history parameters, (4) species distribution models informed by co-occurring species, (5) conservation physiology to inform habitat and threat science, (6) evidence syntheses to evaluate threats and recovery measures, (7) disease-transmission models to understand mussel-host relationships, (8) experimental mesocosms and manipulative experiments to evaluate key habitat stressors, (9) threat and hazard models for predictive applications, and (10) rigorous evaluation of surrogate species. Over a dozen threat- and recovery-focused SARNET research applications are summarized, demonstrating the value of a coordinated research program between academics and government to advance scientific research on, and to support the recovery of, imperilled freshwater species. Des mesures de retablissement reposant sur des travaux de recherche scientifique rigoureux sont necessaires a une conservation efficace. Pour les especes de poissons d'eau douce et mulettes en peril au Canada, il existe de nombreuses lacunes dans la recherche, dues partiellement a la necessite de methodes de recherche specialisees. Le reseau canadien de recherche sur les especes d'eau douce en peril (SARNET) a ete cree et il a cerne ou applique differentes approches visant a combler ces lacunes, dont les suivantes : (1) des populations experimentales captives de recherche, (2) des methodes non letales d'estimation de l'abondance et de la repartition, (3) des methodes de terrain non letales de mesure de parametres du cycle biologique, (4) des modeles de repartition des especes integrant des donnees sur les especes cooccurrentes, (5) la physiologie de la conservation pour soutenir les travaux scientifiques sur les habitats et les menaces, (6) des syntheses de donnees probantes pour evaluer les menaces et measures de retablissement, (7) des modeles de transmission des maladies pour comprendre les relations mulettes-hotes, (8) des mesocosmes experimentaux et des experiences de manipulation pour evaluer des facteurs de stress cles des habitats, (9) des modeles de menaces et de dangers pour des applications predictives et (10) Revaluation rigoureuse d'especes substitutives. Un resume de plus d'une douzaine d'applications des travaux de recherche du SARNET axees sur les menaces et le retablissement est presente, qui demontre l'utilite d'un programme de recherche au sein duquel les travaux de chercheurs universitaires et gouvernementaux sont coordonnes afin de faire avancer la recherche scientifique sur les especes d'eau douce en peril et soutenir leur retablissement. [Traduit par la Redaction], Introduction An important goal of conservation biology is to prevent species extinctions caused by human activity (Soule 1985). When populations decline and become imperilled, various recovery measures are often enacted [...]

Reintroduction is an increasingly common conservation tool used to recover populations of imperilled species, but its success depends on the suitability of the introduced animals' phenotype for their new habitat. For fishes, thermal tolerance may be a key trait in urbanized habitats. We compared thermal tolerance (C[T.sub.max]) among three lineages (western, central, eastern) of imperilled redside dace (Clinostomus elongatus). C[T.sub.max] of eastern adults was 3-4[degrees]C lower than that of the other lineages, but adults of each lineage had similar thermal acclimation responses. In contrast, the acclimation response of juveniles differed by ~80% between the central and western lineages. Using these data, we predicted how each lineage would fare in a hypothetical reintroduction to relatively warm urbanized habitats. Owing to the differences in juvenile acclimation responses, predicted thermal safety margins for the central lineage were double those predicted for the western lineage. Overall, we suggest that C[T.sub.max] is a useful trait to incorporate into the source population selection process; however, there is an urgent need for the establishment of captive experimental research populations of imperilled species to address remaining uncertainties. Si la reintroduction est un outil de conservation de plus en plus utilise pour soutenir le retablissement de populations d'especes menacees, il faut, pour assurer son succes, que le phenotype des animaux introduits convienne a leur nouvel habitat. Pour les poissons, la tolerance a la chaleur pourrait etre un caractere cle dans les habitats urbanises. Nous avons compare la tolerance a la chaleur (C[T.sub.max]) de trois lignees (de l'Ouest, centrale et de l'Est) de menes longs (Clinostomus elongatus), une espece menacee. La C[T.sub.max] d'adultes de l'Est est de 3-4[degrees]C plus basse que celle des autres lignees, mais les adultes des trois lignees presentent des reactions d'acclimatation thermique semblables. En revanche, une difference de ~80 % est relevee entre les reactions d'acclimatation des juveniles des lignees centrale et de l'Ouest. En utilisant ces donnees, nous predisons comment chacune des lignees repondrait a la reintroduction hypothetique dans des habitats urbanises relativement chauds. En raison des differences de reaction d'acclimatation des juveniles, les marges de securite thermique predites pour la lignee centrale sont deux fois plus grandes que les marges predites pour la lignee de l'Ouest. Globalement, nous suggerons que la C[T.sub.max] est un caractere important a incorporer au processus de selection de populations sources; toutefois, il existe un besoin urgent d'etablir des populations de recherche experimentale en captivite d'especes menacees pour etudier les sources d'incertitude qui demeurent. [Traduit par la Redaction], Introduction Fisheries management has a long history of using translocations (moving wild fish from one place to another) and captive breeding programs to augment and expand natural populations of commercially [...]

The analysis of feeding strategies in animals is one of the most important topics in foraging ecology. The individual's foraging behavior depends on both the individual's own actions and the behavior of other foragers. Here we analyse the effect of the sex and group size on the foraging behavior of immature Olrog's Gull (Larus atlanticus Olrog, 1958), endemic to the Atlantic coast of southern South America and regionally listed a threatened species. Birds were captured, banded, sexed, and aged during the non-breeding season in Mar Chiquita coastal lagoon, Argentina. The foraging behavior was quantified by observations made on individuals of known identity, recording the size of foraging groups, as well as prey size and type. Foraging parameters estimated were foraging effort, capture rate, and foraging efficiency. Males spent more time in agonistic behavior and captured larger prey. With an increase in group size, the capture rate, the capture of small crabs by males, and the foraging effort were higher. The agonistic behaviors, size of consumed prey, and foraging effort were affected by individual identity. Our study pinpoints factors underlying variation in the foraging behavior of Olrog's Gulls and illustrates the importance of modelling individual variation when analyzing foraging behavior. Key words: burrowing crab, sex, group size, Larus atlanticus, Olrog's Gull. L'analyse des stratégies d'alimentation chez les animaux constitue l'un des thèmes les plus importants de l'écologie de l'alimentation. Le comportement d'alimentation d'un individu dépend à la fois de ses propres actions et du comportement d'autres individus en quête de nourriture. Nous analysons l'effet du sexe et de la taille du groupe sur le comportement d'alimentation de goélands d'Olrog (Larus atlanticus Olrog, 1958) immatures, une espèce endémique au littoral atlantique du sud de l'Amérique du Sud qui figure sur la liste des espèces menacées dans la région. Des oiseaux ont été capturés, bagués et leur sexe et leur âge ont été déterminés en dehors de la période de reproduction dans la lagune littorale Mar Chiquita (Argentine). Le comportement d'alimentation a été quantifié par des observations faites sur des individus d'identité connue, en notant la taille des groupes d'individus s'alimentant ensemble, ainsi que la taille et le type des proies. Les paramètres relatifs à l'alimentation estimés sont l'effort de quête de nourriture, la fréquence de captures et l'efficacité de la quête de nourriture. Les mâles passaient plus de temps à faire preuve d'un comportement agoniste et capturaient de plus grandes proies. Plus la taille du groupe était grande, plus la fréquence de captures, la capture de petits crabes par les mâles et l'effort de quête de nourriture étaient élevés. Les comportements agonistes, la taille des proies consommées et l'effort de quête de nourriture étaient tous influencés par l'identité de l'individu. L'étude fait ressortir des facteurs qui soustendent les variations du comportement d'alimentation des goélands d'Olrog et illustre l'importance pour l'analyse des comportements d'alimentation de modéliser les variations individuelles. [Traduit par la Rédaction] Mots-clés: crabe fouisseur, sexe, taille du groupe, Larus atlanticus, goéland d'Olrog., Introduction Birds engage daily in a variety of activities among which obtaining food is of paramount importance. The analysis of feeding strategies in animals, and factors affecting this activity, is [...]

Freshwater ecosystems are increasingly impacted by anthropogenic elevated levels of suspended sediment that may negatively affect aquatic organisms, including salamanders. Although increasing fine sediment in streams has been suggested as a reason for population declines, to date no study has empirically assessed the effect of suspended sediment on gilled larval Eastern Hellbenders (Cryptobranchus alleganiensis (Sonnini de Manoncourt and Latreille, 1801)), a critical life-history stage and a species of conservation concern. We used custom respirometers to elucidate effects of suspended sediments on larval Eastern Hellbender oxygen uptake in trials conducted in situ in Georgia (USA) streams. Mean oxygen uptake increased and was significantly higher in trials when larval salamanders were exposed to suspended sediment (mean = 5.06 mg [O.sub.2]/L for 800 mg/L of sediment treatment vs. 2.25 mg [O.sub.2]/L for 0.00 mg/L of sediment control). This may indicate elevated physiological stress in response to short-term exposure to suspended sediments. Qualitatively, individuals in both groups exhibited rocking behavior in response to low oxygen (hypoxia), albeit at different frequencies (sediment exposure = 7.6 rocks/min and control = 2.1 rocks/min). Larval salamanders may be able to temporarily compensate for low oxygen through increased rocking behavior when high suspended sediment loads are present, with future respirometry research needed. Key words: respirometry, sedimentation, salamander conservation, physiology, amphibian, hypoxia, Eastern Hellbender, Cryptobranchus alleganiensis. Les écosystèmes d'eau douce subissent les impacts croissants de teneurs élevées en sédiments en suspension d'origine humaine qui peuvent avoir des effets négatifs sur les organismes aquatiques, y compris les salamandres. S'il a été proposé que l'augmentation des sédiments fins dans les cours d'eau pourrait être une des raisons des baisses de populations, aucune étude à ce jour n'a évalué empiriquement leffet des sédiments en suspension sur les larves à branchies de ménopome (Cryptobranchus alleganiensis (Sonnini de Manoncourt et Latreille, 1801)), un stade clé du cycle biologique de cette espèce dont la conservation est préoccupante. Nous avons utilisé des respiromètres adaptés pour élucider les effets des sédiments en suspension sur la consommation d'oxygène dans des essais menés in situ dans des cours d'eau de la Géorgie (Etats-Unis). L'apport d'oxygène moyen augmente et est significativement plus grand dans les essais dans lesquels les larves de salamandres sont exposées à des sédiments en suspension (moyenne = 5,06 mg [O.sub.2]/L pour le traitement de 800 mg/L de sédiments contre 2,25 mg [O.sub.2]/L pour le traitement témoin de 0,00 mg/L de sédiments). Cela pourrait indiquer un fort stress physiologique en réaction à une exposition de courte durée à des sédiments en suspension. Du point de vue qualitatif, des individus des deux groupes présentaient un comportement de balancement en réponse à la faible oxygénation (hypoxie), bien que de différentes fréquences (exposition aux sédiments = 7,6 balancements/min et témoin = 2,1 balancements/min). Les larves de salamandre pourraient être capables de compenser provisoirement une faible oxygénation par un balancement accru en présence de fortes charges de sédiments en suspension, mais plus de travaux de respirométrie sont nécessaires. [Traduit par la Rédaction] Mots-clés : respirométrie, sédimentation, conservation des salamandres, physiologie, amphibien, hypoxie, ménopome, Cryptobranchus alleganiensis., Introduction Conservation management should incorporate projected environmental changes and ensuing physiological effects on species of conservation concern. Freshwater ecosystems are increasingly threatened by a myriad of anthropogenic-induced environmental stressors, including [...]