Collected Evidence: Collected Evidence: Captive breeding Mallorcan midwife toads Two replicated studies in the UK found that Mallorcan midwife toads produced eggs that were raised to metamorphs or toadlets successfully in captivity. One found that clutches dropped by males were not successfully maintained artificially. One replicated study in the UK found that survival to metamorphosis was 85%. One randomized, replicated, controlled study in the UK found that toads bred in captivity for nine or more generations had slower tadpole development, reduction in one predator defence trait and decreased genetic diversity.      Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F837https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F837Thu, 29 Aug 2013 14:21:37 +0100Collected Evidence: Collected Evidence: Captive breeding salamanders (including newts) Four of six replicated studies (including four small studies) in Japan, Germany, the UK and USA found that eggs were produced successfully in captivity, in one case by one captive-bred female. Two found that production of eggs depended on tank habitat or was more successful in semi-natural compared to laboratory conditions. Captive-bred salamanders were raised to yearlings or a small number of larvae or adults in captivity. One review found that four salamander species bred successfully in captivity, but slimy salamanders produced eggs that did not hatch. One replicated study in Japan found that 60% of Japanese giant salamander eggs survived to hatching in captivity. Two replicated studies (including one small study) in Mexico and the USA found that larval development, body condition and survival of captive-bred amphibians were affected by water temperature, density and whether they were raised under laboratory or semi-natural conditions.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F838https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F838Thu, 29 Aug 2013 14:43:51 +0100Collected Evidence: Collected Evidence: Captive breeding toads Ten replicated studies (including three small studies) in Germany, Italy, Spain, the UK and USA found that toads produced eggs in captivity, in one case by second generation captive females. Eight found that captive-bred toads were raised successfully to tadpoles, toadlets or adults in captivity. Two found that most toads died after hatching or after metamorphosis. Two reviews found mixed results with four species of toad or 21% of captive populations of Puerto Rican crested toad breeding successfully in captivity. Four replicated studies in Germany, Spain and the USA found that reproductive success of captive toads was affected by tank humidity or was higher in outdoor enclosures than indoor tanks. One replicated study in Germany found that survival of European red-bellied toad eggs, tadpoles and juveniles was higher in captivity than the wild.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F848https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F848Thu, 05 Sep 2013 12:44:56 +0100Collected Evidence: Collected Evidence: Carnivores: Feed commercially prepared diets One replicated, before-and-after study in the USA found that providing a commercial diet to maned wolves led to similar dry matter intake and digestibility despite having a lower protein content. One replicated, randomized study of African wildcats in the USA found that feeding a commercial diet decreased crude protein digestibility and increased food intake and faecal output compared to raw meat. One controlled study of African wildcats in the USA found lower organic matter digestibility compared to a ground-chicken diet. One replicated, controlled study in South Africa found that cheetahs fed a commercial diet had a similar likelihood of developing gastritis as those fed horse meat, lower levels of blood protein urea but higher levels of creatine. One study in USA found that cheetahs fed a commercial meat diet or whole chicken carcasses had plasma a-tocopherol, retinol and taurine concentrations within the ranges recommended for domestic cats. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1900https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1900Wed, 24 Jan 2018 09:26:14 +0000Collected Evidence: Collected Evidence: Carnivores: Feed whole carcasses (with or without organs/gastrointestinal tract) Two replicated, before-and-after studies in the USA found that feeding whole carcasses reduced pacing levels in lions, leopards, snow leopards and cougars. However, it increased pacing in tigers. One replicated, randomized, controlled study in Denmark found that when fed whole rabbit, cheetahs had lower blood protein urea, zinc and vitamin A levels compared to supplemented beef. One replicated before-and-after study in Denmark found that feeding whole rabbit showed lower levels of inflammatory bowel indicators in cheetahs. One replicated, randomized study and one controlled study in the USA found that when fed whole 1 to 3 day old chickens, ocelots had lower digestible energy and fat compared to a commercial diet and African wildcats had had lower organic matter digestibility compared to a ground-chicken diet. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1901https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1901Wed, 24 Jan 2018 09:52:15 +0000Collected Evidence: Collected Evidence: Carnivores: Provide bones, hides or partial carcasses One replicated, before-and-after study in the USA and one replicated, controlled study in Finland found that the provision of bones decreased the frequency of stereotypic behaviours in lions, tigers and Arctic foxes. Two replicated, before-and-after studies of felids and red foxes in the USA and Norway found that the provision of bones increased activity and manipulation time. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1902https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1902Wed, 24 Jan 2018 10:01:34 +0000Collected Evidence: Collected Evidence: Carnivores: Feed a plant-derived protein diet One replicated, randomized, controlled study and one replicated, controlled study in the USA found that a plant-derived protein diet increased digestible energy and dry matter digestibility but decreased mineral retention and plasma taurine levels in maned wolves compared to a (supplemented) animal-based protein diet. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1903https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1903Wed, 24 Jan 2018 10:15:58 +0000Collected Evidence: Collected Evidence: Carnivores: Provide food on a random temporal schedule Three replicated, before-and-after studies in Switzerland, Ireland and Canada, UK, Ireland, Namibia and South Africa and one replicated, controlled study in Ireland found that an unpredictable feeding schedule reduced the frequency of stereotypic pacing behaviours in tigers and cheetahs. One replicated, before-and-after controlled study in the USA found that an unpredictable feeding schedule increased territorial behaviour in coyotes but did not affect travelling or foraging. Two before-and-after studies in Switzerland and the USA found that an unpredictable feeding schedule increased behavioural diversity in red foxes and alertness in a black-footed cat. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1904https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1904Wed, 24 Jan 2018 10:20:46 +0000Collected Evidence: Collected Evidence: Carnivores: Allocate fast days One replicated, before-and-after study in the UK found that large felids fed once every three days paced more frequently on non-feeding days. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1906https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1906Wed, 24 Jan 2018 10:38:37 +0000Collected Evidence: Collected Evidence: Carnivores: Alter food abundance or type seasonally No evidence was captured for the effects of altering food abundance or type seasonally on captive carnivores. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1910https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1910Wed, 24 Jan 2018 10:42:25 +0000Collected Evidence: Collected Evidence: Carnivores: Provide food during natural active periods No evidence was captured for the effects of providing food during natural active periods. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1911https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1911Wed, 24 Jan 2018 10:43:17 +0000Collected Evidence: Collected Evidence: Carnivores: Increase variety of food items No evidence was captured on the effect of increasing the variety of food items on captive carnivores. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1912https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1912Wed, 24 Jan 2018 10:43:54 +0000Collected Evidence: Collected Evidence: Carnivores: Alter feeding schedule according to visitor activity No evidence was captured for the effects of altering feeding schedule to visitor activity on captive carnivores. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1914https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1914Wed, 24 Jan 2018 10:46:41 +0000Collected Evidence: Collected Evidence: Carnivores: Hide food around enclosure Four replicated, before-and-after studies in the USA, UK and Germany and one before-and-after study of a black bear, leopard cats, bush dogs, maned wolves and Malayan sun bears found that hiding food increased exploring and foraging behaviours. One replicated, before-and-after study and one before-and-after study in the USA found a decrease in stereotypical pacing in leopard cats and black bear. One before-and-after study in the USA found that hiding food reduced the time Canadian lynx spent sleeping during the day. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1915https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1915Wed, 24 Jan 2018 10:47:53 +0000Collected Evidence: Collected Evidence: Carnivores: Provide food during visitor experiences No evidence was captured for the effects of feeding during visitor experiences on captive carnivores. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1916https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1916Wed, 24 Jan 2018 10:48:57 +0000Collected Evidence: Collected Evidence: Carnivores: Feed individuals separately No evidence was captured for the effects of feeding individuals separately on captive carnivores. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1917https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1917Wed, 24 Jan 2018 10:50:39 +0000Collected Evidence: Collected Evidence: Carnivores: Change location of food around enclosure One replicated, before-and-after study in Ireland found that altering the location of food decreased pacing behaviours in cheetahs. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1918https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1918Wed, 24 Jan 2018 10:51:27 +0000Collected Evidence: Collected Evidence: Carnivores: Feed individuals within a social group No evidence was captured for the effects of feeding individuals within a social group. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1919https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1919Wed, 24 Jan 2018 10:53:13 +0000Collected Evidence: Collected Evidence: Carnivores: Hand-feed No evidence was captured for the effects of hand-feeding on captive carnivores. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1920https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1920Wed, 24 Jan 2018 10:54:17 +0000Collected Evidence: Collected Evidence: Carnivores: Present food in/on water No evidence was captured on the effects of presenting food in/on water on captive carnivores. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1922https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1922Wed, 24 Jan 2018 11:46:32 +0000Collected Evidence: Collected Evidence: Carnivores: Present food frozen in ice Two replicated, before-and-after studies in the USA found that when presented with food frozen in ice, abnormal or stereotypic behaviours decreased and activity levels increased in bears and felids. One replicated, before-and-after study in the USA found that manipulation behaviours increased in lions, whereas a replicated study in the USA found that manipulation behaviours decreased in grizzly bears. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1923https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1923Wed, 24 Jan 2018 11:51:02 +0000Collected Evidence: Collected Evidence: Carnivores: Present food inside objects (e.g. Boomer balls) Two before-and-after studies in Germany and India found that exploratory and foraging behaviours increased and stereotypic behaviours decreased in sloth bears and spectacled bears when presented with food inside objects. One before-and-after study in the USA found that exploring/foraging behaviours decreased in a sloth bear when presented with food inside objects. One replicated study in the USA found that grizzly bears spent a similar time manipulating food in a box and freely available food. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1924https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1924Wed, 24 Jan 2018 12:13:36 +0000Collected Evidence: Collected Evidence: Carnivores: Provide live invertebrate prey, including in feeding devices One replicated study in the USA found that provision of live prey increased explorative behaviours in fennec foxes compared to other types of enrichment. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1926https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1926Wed, 24 Jan 2018 12:19:57 +0000Collected Evidence: Collected Evidence: Carnivores: Provide devices to simulate live prey, including sounds, lures, pulleys and bungees Two before-and-after studies in the USA and the UK found that activity levels and behavioural diversity increased in felids when presented with a lure or pulley system. One replicated, before-and-after study in the USA found that pacing behaviour decreased and walking increased in cougars, but pacing initially increased in tigers, when provided with a carcass on a bungee. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1927https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1927Wed, 24 Jan 2018 12:29:30 +0000Collected Evidence: Collected Evidence: Captive rear in large enclosures prior to release Four studies evaluated the effects of captive rearing mammals in large enclosures prior to release. Two studies were in the USA, one was in Mexico and one was in Australia. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (3 STUDIES) Reproductive success (1 study): A study in Mexico found that peninsular pronghorn taken from the wild and kept in a large enclosure bred successfully and the population increased, providing stock suitable for reintroductions. Survival (2 studies): A replicated, controlled study in USA found that black-footed ferrets reared in outdoor pens had higher post-release survival rates than did ferrets raised indoors. A controlled study in Australia found that Tasmanian devils reared free-range in large enclosures did not have greater post-release survival rates than animals from intensively managed captive-rearing facilities. Condition (1 study): A controlled study in Australia found that Tasmanian devils reared free-range in large enclosures did not gain more body weight post-release compared to animals from intensively managed captive-rearing facilities. BEHAVIOUR (1 STUDY) Behaviour change (1 study): A controlled study in USA found that captive-bred black-footed ferrets raised in large enclosures dispersed shorter distances post-release than did ferrets raised in small enclosures. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2507https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2507Thu, 04 Jun 2020 16:36:49 +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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