Collected Evidence: Collected Evidence: Translocate adult or juvenile reptiles: Sea turtles Two studies evaluated the effects of translocating sea turtles on their populations. One study was global and one was in Japan. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (2 STUDIES) Abundance (1 study): One global review reported that zero of four sea turtle translocations were considered successful. Reproductive success (1 study): One global review reported that zero of four sea turtle translocations found that breeding occurred. Survival (1 study): One study in Japan found that at least two of five wild-caught hawksbill turtles survived at least six months following release. BEHAVIOUR (1 STUDY) Behaviour change (1 study): One study in Japan found that at least two of five wild-caught hawksbill turtles returned to their point of capture after release. Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3706https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3706Mon, 13 Dec 2021 10:47:32 +0000Collected Evidence: Collected Evidence: Translocate adult or juvenile reptiles: Tortoises, terrapins, side-necked & softshell turtles Twenty-six studies evaluated the effects of translocating tortoises, terrapins, side-necked & softshell turtles on their populations. Sixteen studies were in the USA, two were Global and one was in each of Italy, the Seychelles, Madagascar, Cameroon, Egypt, China, Jordan and France. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (24 STUDIES) Abundance (4 studies): One replicated study and one of two global reviews reported that three of eight translocations of turtles resulted in established populations and 15 of 47 reptile translocations resulted in stable or growing populations (review included both wild-caught and captive bred animals). The other review (both wild-caught and captive bred animals) reported that one of five translocation of tortoises and snapping turtles was unsuccessful and four had unknown outcomes. One study in the Seychelles found that 47% of translocated Aldabra giant tortoises were found 12 years after releaser. Reproductive success (5 studies): One global review reported that successful reproduction was found in three of five translocations of tortoises and snapping turtles (review included both wild-caught and captive bred animals). Two of three studies (including one replicated, randomized study) in the USA, Italy and Madagascar reported successful reproduction in translocated populations of gopher tortoises and radiated tortoises. The other study reported no evidence of reproduction for three years following a translocation of European pond turtles. One replicated study in the USA found that translocated female Agassiz’s desert tortoises bred successfully following release, but all hatchlings were sired by resident tortoises, not translocated males. Survival (16 studies): Two of four controlled studies (including one replicated study) in the USA found that translocated eastern box turtles and Eastern painted turtles had lower survival than resident turtles. The other two studies found that translocated desert tortoises and musk turtles had similar survival to that of resident turtles. One replicated study in the USA found that translocated gopher tortoises released into temporary enclosures had similar survival compared to head-started tortoises also released into temporary enclosures over four years. Five of 11 studies (including two replicated, controlled studies) in the USA, Italy, Cameroon, Egypt, China, Jordan and France reported that 69–100% of 3–40 translocated individuals survived for monitoring periods of one month to two years. Four studies reported that 19–43% of 15–109 translocated individuals survived for 2–3 years. The other two studies reported that 0–1% of 15 and 249 translocated individuals survived for up to a year. Condition (3 studies): One controlled study in the USA found that translocated Eastern painted turtles lost more body mass than resident turtles. One controlled, before-and-after, replicated study in the USA found that translocated desert tortoises had similar stress levels compared to resident tortoises. One study in the USA found that one translocated Blanding’s turtle grew over a two-year period following release. BEHAVIOUR (9 STUDIES) Use (2 studies): Two replicated studies (including one controlled study) in the USA found that one of 13 translocated gopher tortoises returned to its point of capture, and no Agassiz’s desert tortoises translocated >5 km returned to their point of capture. Behaviour change (7 studies): Two of six studies (including three replicated, controlled studies) in the USA and Jordan found mixed effects on the movement of translocated red-eared slider turtles in spring or autumn and on the movement and home range size of translocated eastern box turtles compared to residents. Two studies found that four measures of behaviour of translocated musk turtles and home range size of translocated spur-thighed tortoises were similar to residents. One study found that translocated gopher tortoises moved more and had larger home ranges than resident tortoises. The other study found that after ephemeral ponds dried up, translocated Eastern painted turtles did not move to new ponds whereas resident turtles did. One replicated study in France found that the home ranges of translocated European pond turtles were smaller in the year after release compared to the year they were released. Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3708https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3708Mon, 13 Dec 2021 11:22:03 +0000Collected Evidence: Collected Evidence: Translocate adult or juvenile reptiles: Snakes Fourteen studies evaluated the effects of translocating snakes on their populations. Seven studies were in the USA, two were in Antigua, two were global and one was in each of Canada, South Korea and Australia. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (12 STUDIES) Abundance (6 studies): One of two global reviews reported that 15 of 47 reptile translocations (number of snake species not provided) resulted in stable or growing populations (both wild-caught and captive bred reptiles or snakes). The other review reported that the outcome of one indigo snake reintroduction was unknown. One replicated study in the USA found that five of 13 translocations of snakes resulted in established populations. Three studies in Canada and Antigua reported that 3–7 years after translocations of red-sided garter snakes and Antiguan racer snakes, greater numbers were counted. Reproductive success (3 studies): One global review reported that breeding occurred in nine of 22 reptile translocations (of both wild-caught and captive bred animals). Two studies in Antigua reported successful reproduction in translocated populations of Antiguan racer snakes three years after release. Survival (8 studies): Three controlled studies in the USA and Australia found that translocated timber rattlesnakes, northern water snakes and dugite snakes had lower survival than resident snakes, and in one study no translocated snakes survived a year. One controlled study in the USA found that ratsnakes held in captivity for 1–7 years before release had lower survival compared to snakes held for 7–18 days or resident snakes. Four studies (including one replicated, controlled study) in Canada, the USA and South Korea reported that 12–45% of snakes survived for three months to eight years after release. Condition (1 study): One controlled study in the USA found that translocated northern water snakes had similar growth rates compared to resident snakes. BEHAVIOUR (5 STUDIES) Behaviour change (5 studies): Three of five controlled studies in the USA found that differences in movement and home range size of translocated and resident hognose snakes, ratsnakes and dugite snakes were mixed. The other two studies found that translocated timber rattlesnakes and northern water snakes had larger home ranges than residents. One study also found that translocated timber rattlesnakes had higher daily movements than resident snakes. Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3716https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3716Mon, 13 Dec 2021 15:01:40 +0000Collected Evidence: Collected Evidence: Translocate adult or juvenile reptiles: Lizards Seventeen studies evaluated the effects of translocating lizards on their populations. Six studies were in New Zealand, three were in the Bahamas, two were in Australia, two were global and one was in each of the Caribean, St. Lucia, Turks and Caicos Islands and Anguilla. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (16 STUDIES) Abundance (10 studies): Three of four reviews that were global and in New Zealand and the Caribean reported that 13–32% of reptile or lizard translocations resulted in stable or growing populations (both wild-caught and captive bred animals). The other review reported that populations from eight of 13 iguana translocations survived for at least 5–20 years. Two of six studies (include one site comparison study) in St. Lucia, the Bahamas and New Zealand reported that translocated lizard populations increased over 3–10 years. Two studies reported that translocated populations remained stable for one and 6–12 years. One study reported that a translocated population declined over 1–2 years. The other study reported that a translocated population of iguanas survived for at least 40 years. Reproductive success (5 studies): Two reviews that were global and in New Zealand reported that breeding occurred in 20% and at least 30% of lizard translocations (both wild-caught and captive bred animals). Three studies (including one replicated study) in New Zealand, Turks and Caicos Islands and the Bahamas reported successful reproduction in a translocated Whitaker’s skink population, a Turks and Caicos Rock Iguana population and one of two San Salvador rock iguana populations after 14 months to five years. Survival (10 studies): Seven of eight studies (including one replicated, controlled study) in New Zealand, Turks and Caicos Islands, Australia, the Bahamas and Anguilla found that 40–85% of translocated lizards survived for at least 3 months to seven years or that no mortality was reported in the first year after release. The other study reported that at least one lesser Antillean iguana survived for at least two years. One review in New Zealand found that 9% of lizard translocations (both wild-caught and captive-bred animals) resulted in complete failure (no individuals survived). One site comparison study in New Zealand found that 1–2 years after a translocation of shore skinks, individuals representing three of four pattern types originally released still survived. Condition (1 study): One replicated, controlled study in Australia found that 67% of Napoleon’s skinks gained weight following release. BEHAVIOUR (2 STUDIES) Use (1 study): One replicated, controlled study in Australia found that all six Napoleon’s skinks translocated to restored mining sites moved into unmined forest within a week of release. Behaviour change (1 study): One replicated, before-and-after, controlled study in Australia found that provision of artificial burrows and supplementary food affected the use of bare ground areas by pygmy blue tongue lizard translocated into enclosures.  Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3719https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3719Mon, 13 Dec 2021 15:36:46 +0000Collected Evidence: Collected Evidence: Translocate adult or juvenile reptiles: Crocodilians Two studies evaluated the effects of translocating crocodilians on their populations. Both studies were global. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (2 STUDIES) Abundance (2 studies): Two global reviews reported four of five crocodilian translocations and 15 of 47 reptile translocations resulted in stable or growing populations (included both wild-caught and captive bred animals). Reproductive success (2 studies): One global review reported that breeding occurred in at least two of five crocodilian translocations (included both wild-caught and captive bred animals). BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3722https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3722Mon, 13 Dec 2021 17:10:16 +0000Collected Evidence: Collected Evidence: Translocate adult or juvenile reptiles: Tuatara Four studies evaluated the effects of translocating tuatara on their populations. Three studies were in New Zealand and one was global. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (4 STUDIES) Abundance (2 studies): One global review reported that 15 of 47 reptile translocations resulted in stable or growing populations (review included both wild-caught and captive bred animals). One study in New Zealand found that nine years after a translocation of 32 tuatara to an island where they had previously gone extinct, there was a population of 50 individuals. Reproductive success (2 studies): One of two studies (including one controlled study) in New Zealand reported successful reproduction in one population of translocated tuatara. The other study reported no breeding during the six years following translocation. Survival (2 studies): Two studies (including one controlled study) in New Zealand reported that 61–73% of translocated tuatara were recaptured over a six year period or survived for 9–12 month following release. Condition (1 study): One controlled study in New Zealand found that translocated adult tuatara increased their body weight by 41% following release. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3723https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3723Mon, 13 Dec 2021 17:16:28 +0000Collected Evidence: Collected Evidence: Use holding pens or enclosures at release site prior to release of wild reptiles Seven studies evaluated the effects of using holding pens or enclosures at release sites prior to release of wild reptiles. Four studies were in the USA and one study was in each of Australia, New Zealand and the UK. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (5 STUDIES) Reproductive success (1 study): One replicated, controlled study in New Zealand found that in a site where jewelled geckos were translocated into holding pens prior to release, more gravid females were found compared to a site where holding pens were not used. Survival (4 studies): Two of three controlled studies (including one replicated study) in the USA and the UK found that gopher tortoises translocated into holding pens with artificial burrows prior to release or viviparous lizards released into an enclosure had higher survival (recaptured) or assumed survival (dug burrows) than individuals released without pens or enclosures. The other study found that translocating eastern box turtles into holding pens, or keeping them in pens for longer, did not affect post-release survival. One replicated study in the USA found that survival of Florida sand skinks within holding pens with different combinations of habitat features (trees, shade cloth, woody debris) ranged from 49–79% over two years. Condition (1 study): One randomized, controlled study in the UK found that viviparous lizards released into an enclosure had similar body condition compared to those released without an enclosure. BEHAVIOUR (4 STUDIES) Behaviour change (4 studies): Two of three controlled studies (including two replicated studies) in the USA and New Zealand found that gopher tortoises and jewelled geckos translocated into holding pens prior to release dispersed away from the release site less frequently than those not held in pens. One study also found that the activity area of tortoises held in pens was smaller in the year of release, but similar in the year after release, compared to those not held in pens. The other study found that translocating eastern box turtles into holding pens, or keeping them in pens for longer, did not affect post-release dispersal behaviour. One controlled study in Australia found mixed effects on a range of behavioural measures of translocating pygmy bluetongue lizards into holding pens with artificial burrows for one day compared to five days. Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3724https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3724Mon, 13 Dec 2021 17:26:44 +0000Collected Evidence: Collected Evidence: Release reptiles into burrows One study evaluated the effects of releasing reptiles into burrows on their populations. This study was in the USA. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Survival (1 study): One replicated study in the USA found that both releasing translocated gopher tortoises into abandoned or artificial burrows or releasing without burrows had low success, but providing burrows inside release pens resulted in more successful translocations. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3725https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3725Mon, 13 Dec 2021 17:41:23 +0000Collected Evidence: Collected Evidence: Release reptiles outside of their native range Seven studies evaluated the effects of releasing reptiles outside of their native range on their populations. Three studies were in the US Virgin Islands and one was in each of the USA, Mauritius, the Galápagos and New Zealand. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (7 STUDIES) Abundance (1 study): One replicated study in the US Virgin Islands found that following a translocation of St. Croix ground lizards to a new island, the population grew over a 10-year period. Occupancy/range (2 studies): One replicated, randomized study in the US Virgin Islands found that following a release outside of their native range, St. Croix ground lizards were still present five years later. One randomized study in the US Virgin Islands found that following a release outside of their native range, the area occupied by a population of St. Croix ground lizards increased from the 5th to 7th year following release. Reproductive success (3 studies): Three studies (including two replicated studies) in Maritius, the US Virgin Islands and New Zealand found that following releases outside of their native ranges, there was evidence of reproduction in released populations of Aldabra giant tortoises and Madagascar radiated tortoises, St. Croix ground lizards and Otago skinks after 11 months and 5–7 years. Survival (3 studies): Two studies (including one replicated, before-and-after study) in the Galápagos and New Zealand found that following releases outside of their native ranges, 77% of sterilized Galápagos giant tortoises and 63% of Otago skinks survived for 11 months or one year. One study in the USA found that annual survival of a second group of gopher tortoises translocated to an island was lower for newly released tortoises compared to established individuals from a previous release when the island had been outside of the native range. Condition (1 study): One replicated, before-and-after study in the Galápagos found that sterilized Galápagos giant tortoises translocated outside of their native range as part of an ecological replacement gained weight during the first year following their release as. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3738https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3738Tue, 14 Dec 2021 10:06:29 +0000
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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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