Collected Evidence: Collected Evidence: Release translocated/captive-bred mammals to areas outside historical range Seven studies evaluated the effects of releasing translocated or captive-bred mammals to areas outside their historical range. Three studies were in Australia, one study was in each of Kenya, France and South Africa, and one was a review of studies in Andorra, Spain and France. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (7 STUDIES) Abundance (5 studies): Three of four studies in Kenya, Australia, France, and South Africa found that after translocating mammals to areas outside their historical range, populations increased for Alpine marmots, most of 22 herbivorous species and bridled nailtail wallabies (including captive and enclosure bred animals). A study in Kenya found that a population of translocated roan persisted for more than six years but did not increase. A review of studies in Andorra, Spain and France found that following translocation to areas outside their native range, alpine marmots had similar densities and family group sizes to those of populations in their native range. Reproductive success (1 study): A study in Kenya found that a population of roan translocated into an area outside their native range persisted and bred for more than six years. Survival (3 studies): A study in Australia found that captive-bred, translocated and enclosure born bridled nailtail wallabies released into areas outside their historical range had annual survival rates of 40–88% over four years. A study in Australia found that most captive-bred Tasmanian devils released into an area outside their native range survived over four months. A study in Australia found that half the captive-bred and wild-caught translocated eastern barred bandicoots released to a red fox-free island outside their historical range survived for at least two months. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2443https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2443Tue, 02 Jun 2020 10:27:10 +0100Collected Evidence: Collected Evidence: Release translocated/captive-bred mammals at a specific time (e.g. season, day/night) Seven studies evaluated the effects of releasing translocated or captive-bred mammals at a specific time (season or day/night). Three studies were in the USA and one each was in the UK, Canada, Ireland and Hungary. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (7 STUDIES) Survival (7 studies): Four of five studies in the UK, Canada and the USA found that translocated common dormice, black bears and Canadian lynx and captive-bred swift foxes released in a specific season had higher survival rates than those released during another season. The other study found that red squirrels translocated in autumn and winter had similar survival rates. A randomised, replicated, controlled study in Hungary found that translocated European ground squirrels released during the morning had higher recapture rates than those released during the afternoon. A study in the USA found that most translocated kangaroo rats released at dusk in artificial burrows supplied with food died within five days of release. Condition (1 study): A study in the UK found that common dormice translocated during summer lost less weight than those translocated during spring. BEHAVIOUR (2 STUDIES) Behaviour change (2 studies): Two studies in the UK and USA found that common dormice translocated during spring and black bears translocated during winter travelled shorter distances or settled closer to the release site than those translocated during summer. Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2447https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2447Tue, 02 Jun 2020 10:40:47 +0100Collected Evidence: Collected Evidence: Release translocated/captive-bred mammals into area with artificial refuges/breeding sites Seventeen studies evaluated the effects of releasing translocated or captive-bred mammals into areas with artificial refuges or breeding sites. Five studies were in the USA, three were in Australia, three were in Spain, two were in the UK and one was in each of Ireland, South Africa, Hungary and Slovakia, the Czech Republic and Poland. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (15 STUDIES) Abundance (5 studies): Two of three studies (two replicated, two controlled) in Spain and the USA found that translocation release sites with artificial burrows provided had higher abundances of European rabbits and densities of California ground squirrels compared to those without. The other study found that abundance of European rabbits following translocation was similar with and without artificial burrows provided. A replicated, controlled study in the USA found that after translocating black-tailed prairie dogs to areas with artificial burrows, colonies increased in size. A before-and-after study in Spain found that translocating European rabbits into areas with artificial refuges to supplement existing populations did not alter rabbit abundance, although two of three populations persisted for at least three years. Reproductive success (4 studies): Three studies in Australia, Ireland and the UK found that released captive-bred sugar gliders, most translocated female red squirrels and some translocated pine martens provided with nest boxes and supplementary food reproduced. A study of 12 translocation projects in Slovakia, the Czech Republic and Poland found that translocated European ground squirrels released initially into enclosures or burrows with retention caps reproduced after release, whereas those without enclosures or burrows dispersed from release sites. Survival (9 studies): Five of eight studies in Australia, the USA, UK, Ireland and South Africa found that at release sites with artificial refuges, and in some cases food provided, a population of captive-bred sugar gliders survived at least three years, two of three populations of red-tailed phascogales survived for more than four years, most translocated black bears survived at least one year and over half translocated red squirrels and pine martens survived 8-12 months. Three studies found that at release sites with artificial refuges, food and in one case water provided, no translocated red squirrels survived more than five months, all translocated rock hyraxes died within three months and most translocated Tipton and Heermann’s kangaroo rat spp. died within five days. A randomised, replicated, controlled study in Hungary found that translocated European ground squirrels released into plugged artificial burrows had higher recapture rates than those released into unplugged artificial burrows. BEHAVIOUR (3 STUDIES) Use (2 studies): Two studies in Australia found that released captive-bred sugar gliders used artificial nest boxes provided. Behaviour change (1 study): A replicated, before-and-after study in the USA found that translocated Utah prairie dogs released into an area with artificial burrows, after the control of native predators, tended to leave the release site and spent more time being vigilant than before. Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2453https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2453Tue, 02 Jun 2020 11:09:26 +0100Collected Evidence: Collected Evidence: Release translocated/captive-bred mammals in larger unrelated groups Five studies evaluated the effects of releasing translocated or captive-bred mammals in larger unrelated groups. Two studies were in South Africa, one was in Namibia and South Africa, one was in the USA and one was in Australia. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (5 STUDIES) Reproductive success (3 studies): A replicated, paired sites study in the USA found that black-tailed prairie dogs translocated in larger groups had higher reproductive success than smaller groups. A study in South Africa found that Cape buffalo translocated to a fenced reserve as a larger group formed a single herd and reproduced, whilst a smaller group separated. A study in South Africa found that rehabilitated and captive-bred cheetahs released in groups (unrelated and family) and as individuals reproduced. Survival (4 studies): A replicated, paired sites study in the USA found that black-tailed prairie dogs translocated in larger groups had higher initial daily survival rate than smaller groups. Two studies (one controlled) in Namibia and South Africa and Australia found that releasing translocated black rhinoceroses and burrowing bettongs in larger groups did not increase survival. A study in South Africa found that most adult rehabilitated and captive-bred cheetahs released in groups (unrelated and family) and as individuals survived at least one year. BEHAVIOUR (2 STUDIES) Behaviour change (2 studies): A replicated, paired sites study in the USA found that black-tailed prairie dogs translocated in larger groups attracted more immigrants than smaller groups. A study in South Africa found that Cape buffalo translocated as a larger group formed a single herd and stayed in the fenced reserve, whilst a smaller group scattered and escaped the reserve. Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2462https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2462Tue, 02 Jun 2020 12:01:41 +0100Collected Evidence: Collected Evidence: Release translocated/captive-bred mammals in family/social groups Twenty-six studies evaluated the effects of releasing translocated or captive-bred mammals in family or social groups. Eleven were in the USA, seven were in South Africa and one was in each of Poland, Zimbabwe, along the USA–Canada border, Russia, Italy, Canada, China and India. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (22 STUDIES) Abundance (4 studies): A study in the USA found that a translocated population of Rocky Mountain bighorn sheep released in groups increased at a similar rate to that of a population newly established through natural recolonization. A replicated, controlled study in the USA found that after translocating black-tailed prairie dogs in social groups to areas with artificial burrows, colonies increased in size over four years. A replicated study in Canada found that following translocation of elk, most of which had been kept in holding pens in groups, numbers increased at two of four sites. A study in the USA found that following the release of captive-reared bighorn sheep in groups, the overall population declined over 14 years. Reproductive success (11 studies): A study in the USA found that captive-reared bighorn sheep released in groups had similar population recruitment rates compared to wild-reared sheep. A replicated, paired study in the USA found that black-tailed prairie dogs translocated as family groups had higher reproductive success than those translocated in non-family groups. A replicated study in the USA found that translocated gray wolves had similar breeding success when adult family groups were released together from holding pens or when young adults were released directly into the wild. Six of eight studies (one replicated) in Poland, Russia, South Africa, the USA and the USA–Canada border found that when translocated and/or captive-bred animals were released in social or family groups, cheetahs, European bison, lions, African wild dogs, most European beavers and some swift foxes reproduced successfully. One study found that one of two translocated Cape buffalo groups released after being held in a holding pen formed a single herd and reproduced, while the other scattered and escaped the reserve. One study found that no Gunnison's prairie dogs reproduced during the first year. Survival (19 studies): One of three studies (one controlled, before-and-after) in the USA found that when translocated or captive-bred animals were released in family or social groups, captive-reared bighorn sheep had similar survival compared to wild-reared sheep, whereas two found lower survival compared to wild white-tailed deer and San Joaquin kit foxes. Three replicated studies (one controlled, one paired) in the USA found that when translocated as a social or family group, black‐tailed prairie dogs had higher and white-tailed deer and gray wolves had similar survival rates to those translocated as unrelated groups or individuals. Ten studies (one replicated) in Poland, Russia, Italy, South Africa, the USA, USA–Canada border, China and India found that when translocated and/or captive-bred animals were released in social or family groups, a population of Przewalski’s horses and European bison persisted 5-11 years, lions, most swift foxes and European beavers and half or more cheetahs survived for at least one year, and one-horned rhinoceroses and over half of Gunnison's prairie dogs and Eurasian badgers survived at least 1-6 months. Three studies in the USA and South Africa found that when translocated or captive-bred animals were released in family or social groups (some provided with artificial refuges and/or supplementary food), most Mexican wolves did not survive over eight months and all rock hyraxes died within 90 days. A study in South Africa found that translocated and captive-bred African wild dogs released in family groups into fenced reserves had high survival rates. Condition (1 study): A study in China found that following the release of captive-bred Przewalski’s horses in groups, the population had a lower genetic diversity than two captive populations. BEHAVIOUR (4 STUDIES) Behaviour change (4 studies): Two replicated, controlled (one before-and-after) studies in the USA found that when translocated as a social or family group, white-tailed deer had similar average dispersal distances and Utah prairie dogs had similar release site fidelity and post-release behaviour compared to those translocated as unrelated groups. One found that deer translocated together did not stay together, whether they had previously been part of the same social group or not. A study in Zimbabwe found that a translocated lion family joined with immigrant lions and formed a new pride. A study in South Africa found that translocated lions that were released in groups that had already been socialised and formed into prides, established stable home ranges. Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2463https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2463Tue, 02 Jun 2020 12:17:05 +0100Collected Evidence: Collected Evidence: Release translocated/captive-bred mammals to islands without invasive predators Six studies evaluated the effects of releasing translocated or captive-bred mammals to islands without invasive predators. The six studies were in Australia. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (7 STUDIES) Abundance (2 studies): A study in Australia found that following release of captive-bred dibblers on to an island free of introduced predators, numbers increased. A replicated study in Australia found that following release of captive-bred and wild-born brush-tailed bettong onto islands free of foxes or cats, numbers increased on two of four islands. Reproductive success (3 studies): A study in Australia found that captive-bred proserpine rock-wallabies released on an island without introduced predators established a breeding population. Two studies in Australia found that following release on to islands without invasive predators, captive-bred rufous hare-wallabies and captive-bred dibblers. Survival (3 studies): A review of 28 translocation studies in Australia found that 67% of marsupial populations translocated to islands without predators survived more than five years, compared to 0% translocated to islands with predators and 20% translocated to the mainland. A study in Australia found that most captive-bred rufous hare-wallabies released on an island without non-native predators survived more than a year. A replicated study in Australia found that wild-born golden bandicoots descended from translocated populations released onto two predator-free islands persisted for 2–3 years. Condition (1 study): A replicated study in Australia found that wild-born golden bandicoots descended from translocated populations that had been released onto two predator-free islands, maintained genetic diversity relative to founder and source populations. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2464https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2464Tue, 02 Jun 2020 18:35:43 +0100Collected Evidence: Collected Evidence: Release translocated/captive-bred mammals in areas with invasive/problematic species eradication/control Twenty-two studies evaluated the effects of releasing translocated or captive-bred mammals in areas with eradication or control of invasive or problematic species. Sixteen studies were in Australia, four were in the USA, and one in the UK. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (21 STUDIES) Abundance (4 studies): A replicated study in Australia found that increasing amounts of regular predator control increased population numbers of released captive-bred eastern barred bandicoots. Two studies in Australia found that following eradication or control of invasive species, a population of translocated and released captive-bred burrowing bettongs increased and a population of translocated western barred bandicoots increased over four years. A study in Australia found that following the release of captive-bred bridled nailtail wallabies and subsequent predator controls, numbers increased over a three years, but remained low compared to the total number released. Reproductive success (2 studies): A study in Australia found that four of five captive-bred mammal populations released into a predator-free enclosure and one population released into a predator-reduced enclosure produced a second generation, whereas two populations released into an unfenced area with ongoing predator management did not survive to reproduce. A study in Australia found that most female captive-reared black-footed rock-wallabies released into a large predator-free fenced area reproduced. Survival (18 studies): Ten studies (one controlled, three replicated, two before-and-after studies) in Australia, and the UK found that following the eradication/control of invasive species (and in some cases release into a fenced area), a translocated population of woylies, western barred bandicoots and red-tailed phascogales survived over four years, released captive-bred eastern barred bandicoots survived up to three years at five of seven sites, offspring of translocated golden bandicoots survived three years, over half of released captive-reared black-footed rock-wallabies survived over two years, captive-bred water voles survived for at least 20 months or over 11 months at over half of release sites, most released captive-bred hare-wallabies survived at least two months, most captive-bred eastern barred bandicoots survived for over three weeks. A replicated study in Australia found that after the control of invasive species, four translocated populations of burrowing bettongs died out within four months. A review of studies in Australia found that in seven studies where red fox control was carried out before or after the release of captive-bred eastern-barred bandicoots, survival varied. A study in Australia found that four of five captive-bred mammal populations released into a predator-free enclosure and one population released into a predator-reduced enclosure survived, whereas two populations released into an unfenced area with ongoing predator management did not. A study in Australia found that captive-bred bridled nailtail wallabies released from holding pens in areas where predators had been controlled had similar annual survival rates to that of wild-born translocated animals. Two studies (one replicated) in the USA found that where predators were managed, at least half of released captive-bred black-footed ferrets survived more than two weeks, but that post-release mortality was higher than resident wild ferrets. A before-and-after study in the USA found following the onset of translocations of black bears away from an elk calving site, survival of the offspring of translocated elk increased. Condition (2 studies): A study Australia found that wild-born golden bandicoots, descended from a translocated population released into a predator-free enclosure, maintained genetic diversity relative to the founder and source populations. A replicated, before-and-after study in Australia found that one to two years after release into predator-free fenced reserves, translocated eastern bettongs weighed more and had improved nutritional status compared to before release. BEHAVIOUR (1 STUDY) Behaviour change (1 study): A replicated, before-and-after study in the USA found that translocated Utah prairie dogs released after the control of native predators into an area with artificial burrows showed low site fidelity and different pre- and post-release behaviour. Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2469https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2469Wed, 03 Jun 2020 14:51:14 +0100
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What Works in Conservation

What Works in Conservation provides expert assessments of the effectiveness of actions, based on summarised evidence, in synopses. Subjects covered so far include amphibians, birds, mammals, forests, peatland and control of freshwater invasive species. More are in progress.

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