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Captive breeding programs are widely applied by conservation practitioners as a means of conserving, reintroducing, and supplementing populations of imperilled freshwater fishes and mussels. We conducted a systematic map to provide an overview of the existing literature on the effectiveness of captive breeding and release programs. A key finding is that there is limited evaluation of the effectiveness of such programs at all three stages (i.e., broodstock collection, rearing/ release methods, and post-release monitoring). We identified clusters of evidence for evaluating supplementation associated with rearing/release methods for fish growth and survival metrics, and the monitoring stage for fish genetic diversity, growth, and survival metrics, primarily focused on salmonids. However, many studies had inadequate experimental designs (i.e., lacked a comparator). Overall, there was a paucity of studies on the effectiveness of captive breeding programs for imperilled freshwater mussels, highlighting the need to make such information broadly available when studies are undertaken. Outputs from this systematic map (i.e., the map database and heatmaps) suggest that the effectiveness of captive breeding and release programs requires further systematic evaluation. Des programmes de reproduction en captivite sont largement utilises par les specialistes de la conservation comme moyen de conservation, de reintroduction et de supplementation de populations menacees de poissons d'eau douce et de mulettes. Nous avons realise une cartographie systematique pour dresser un portrait du corpus documentaire existant sur l'efficacite des programmes de reproduction en captivite et de lacher. Une des constatations cles est le fait que revaluation de l'efficacite des trois etapes de tels programmes (c.-a-d., prelevement de geniteurs, methodes d'elevage/de lacher et surveillance apres le lacher) est limitee. Nous avons cerne des groupements de donnees probantes pour les evaluations de la supplementation associees aux methodes d'elevage/de lacher pour des parametres relies a la croissance et la survie des poissons, et l'etape de surveillance pour des parametres relies a la diversite genetique, la croissance et la survie des poissons, axes principalement sur les salmonides. Le schema experimental de nombreuses etudes est toutefois inadequat (c.-a-d., absence de comparateur). Globalement, les etudes sur l'efficacite des programmes de reproduction en captivite pour les mulettes menacees sont rares, soulignant la necessite d'assurer une large disponibilite de ce type d'information quand de telles etudes sont realisees. Les extrants de cette cartographie systematique (c.-a-d., la base de donnees en decoulant et les cartes de densite) font ressortir la necessite d'une evaluation systematique plus poussee de l'efficacite de programmes de reproduction en captivite et de lacher. [Traduit par la Redaction], Introduction Global freshwater biodiversity has declined by over 80% since the 1970s, to the point where it is clearly in crisis (Harrison et al. 2018). Freshwater fishes have some of [...]

The monodontids--narwhals, Monodon monoceros, and belugas, Delphinapterus leucas--are found in much of the Arctic and in some subarctic areas. They are hunted by indigenous subsistence users. In the past, some populations were substantially reduced by commercial hunting and culling; more recently, some populations have declined due to uncontrolled subsistence hunting and environmental degradation. Monodontids are impacted increasingly by human activities in the Arctic including ship and boat traffic, industrial development, icebreaking, seismic surveys, competition with fisheries, and alteration of habitat due to climate change. Since comprehensive reviews in the 1990's, substantial new information has become available on both species and on changes to their habitat as a result of human activities and climate change. Thus NAMMCO and partners undertook an updated review in 2017. The review recognized 21 extant beluga stocks, 1 extirpated beluga stock, and 12 stocks of narwhals. The available information on each stock regarding population size, depletion level, current and past removals, and trends in abundance was reviewed to determine status. Concern was expressed where the lack of information prevented reliable assessment, removals were thought to be unsustainable, or the population was deemed at risk of declining even without direct removals by hunting. Beluga stocks of greatest concern are the small stocks in Ungava Bay (possibly extirpated), Cook Inlet (ca 300), St. Lawrence Estuary (ca 900), and Cumberland Sound (ca 1,100), and the stocks with uncertainty in Eastern Hudson Bay and the Barents-Kara-Laptev Seas. Narwhal stocks of greatest concern are those in Melville Bay and East Greenland., Introduction The family Monodontidae is comprised of the narwhal, Monodon monoceros, and the beluga or white whale, Delphinapterus leucas (Rice, 1998). These two species are found in much of the [...]

Many natural and manmade entities could conceivably pose health risks to humans. Those risks cannot be evaluated and quantified with objective scientific tests because of ethical concerns about human testing. [...]

Ecotourism is examined as another form of development rather than as a method of conservation. Topics include the facilities tourism requires, such as restrooms and food concessions, the resulting sanitation and litter problems, and the need for roads to transport large numbers of tourists, along with transport vehicles, the majority of which burn fossil fuels.

Research shows that the US Dept. of Agriculture's Conservation Reserve Program has had a positive impact on duck population recruitment in the nation's northern midwest region. Studies conducted between 1992 and 1997 indicate that recruitment and nest success are 30% and 46% higher, respectively, with a total of 12.4 mil new recruits to fall flight during this period.

An evaluation is presented on riparian ecosystem management practices and their impact on freshwater turtle migration, nesting, feeding and wintering behaviors. Research results from four countries and eight US states indicate that riparian zones are typically too narrow to properly accommodate turtle habitat needs.

Research indicates that genetic diversity in the endangered North Atlantic right whale has not changed significantly since the late 19th century. Findings were based on DNA data obtained from historical right whale museum specimens from 1885-1910, and the findings suggest that conservation measures in place since 1935 have helped protect the species' genetic diversity.

In 1958, the Arkansas Game and Fish Commission began translocating black bears (Ursus americanus) from Minnesota to the Interior Highlands (Ozark and Ouachita mountains) of Arkansas where bears had been extirpated early in this century. This project continued for 11 years with little public imput, during which time an estimated 254 bears were released. We estimate there are now >2,500 bears in the Interior Highlands of Arkansas, Missouri, and Oklahoma, making it one of the most successful translocations of a Carnivora. Factors that contributed to the success include use of wild-captured animals, elimination of major factors associated with extirpation, release into prime habitats within the former range, multiple release sites, release of 20-40 animals/year for eight years, and release of mostly males prior to release of mostly females. Studies on two allopatric populations demonstrate that they are now diverging in some demographic characteristics, including litter size, cub survivorship, and adult sex-ratio. Translocation of black bears to the Interior Highlands is successful in terms of numbers of animals, but it will not be truly successful until people accept black bears as part of the regional fauna. To that end, those associated with management and research of bears in Arkansas are now focussing on public education and control of nuisance bears.

Each day, the village chief watched as a nearby squatter settlement mushroomed on the periphery of Zambia's Kafue National Park. He ordered the squatters who poached the park's wildlife to […]

Human's nature towards conservation of creatures and plants that have become extinct are discussed. One of the most famous extinct birds, the ivory-billed woodpecker of the southern states of the US is an example.

The article critiques the San Clemente loggerhead shrike recovery program, as its predator control component is contributing to the endangerment of the San Clemente Island fox. An ecosystem approach to species recovery would alleviate this conflict.

An overview is presented on the introduction of Texas cougars (Puma stanleyana) to genetically bolster shrinking Florida panther (Puma concolor coryi) populations. The authors caution against the high rates of introgression, which could result in the eradication of Florida panther genes, and support a landscape-based recovery approach.

Inadequate legal protections may drive Europe's Iberian lynx to extinction. The species' members number just 150, and the population is threatened by dams, roads and intensive agriculture that fragment its habitat. While facilities capable of captive breeding exist, political infighting prevents them from being used.