Collected Evidence: Collected Evidence: Rehabilitate and release injured or accidentally caught individuals: Sea turtles Four studies evaluated the effects of rehabilitating and releasing injured or accidentally caught sea turtles on their populations. Two studies were in the USA and one was in each of the Philippines and the western Mediterranean. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (4 STUDIES) Survival (4 studies): One study in the Philippines and one controlled study in the western Mediterranean found that of 79 rehabilitated sea turtles two were found dead and two alive within 1–5 months of release, and six rehabilitated loggerhead turtles survived for at least five months following release. Two studies in the USA found that around one third of stranded sea turtles and 96% of sea turtles caught in fishing gear could be rehabilitated and released. One study also found that the chance of surviving the rehabilitation process varied with species. BEHAVIOUR (1 STUDY) Behaviour change (1 study): One replicated, controlled study in the western Mediterranean found that six rehabilitated loggerhead turtles showed similar behaviour to wild caught turtles across 46 of 54 comparisons. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3740https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3740Tue, 14 Dec 2021 10:23:55 +0000Collected Evidence: Collected Evidence: Rehabilitate and release injured or accidentally caught individuals: Tortoises, terrapins, side-necked & softshell turtles Four studies evaluated the effects of rehabilitating and releasing injured or accidentally caught tortoises, terrapins, side-necked and softshell turtles on their populations. Two studies were in France and one was in each of South Africa and the USA. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (4 STUDIES) Reproductive success (1 study): One controlled study in France found that some rehabilitated Hermann’s tortoises were observed mating with resident tortoises following release. Survival (4 studies): One controlled, before-and-after study in France found that survival of rehabilitated and released Hermann’s tortoises was similar compared to wild tortoises over a two-year period. Three studies (including two replicated studies) in South Africa, France and the USA found that Babcock’s leopard tortoises, Herman’s tortoises and ornate box turtles released following rehabilitation survived for varying durations during monitoring periods that ranged from three months to 25 months or until the end of the active season during the year of release. BEHAVIOUR (2 STUDIES) Behaviour change (2 studies): One controlled study in France found that 12 rehabilitated Herman’s tortoises remained within 2 km of their release site over a three-month period. This study also found that daily movement of rehabilitated and released tortoises was similar to residents. One controlled, before-and-after study in France found that rehabilitated tortoises released in autumn took longer to establish a home range than those released in spring. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3741https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3741Tue, 14 Dec 2021 10:34:25 +0000Collected Evidence: Collected Evidence: Rehabilitate and release injured or accidentally caught individuals: Snakes & lizards We found no studies that evaluated the effects of rehabilitating and releasing injured or accidentally caught snakes and lizards on their populations. ‘We found no studies’ means that we have not yet found any studies that have directly evaluated 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%2F3742https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3742Tue, 14 Dec 2021 10:44:54 +0000Collected Evidence: Collected Evidence: Rehabilitate and release injured or accidentally caught individuals: Crocodilians One study evaluated the effects of rehabilitating and releasing injured or accidentally caught crocodilians on their populations. This study was in India. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Reproductive success (1 study): One study in India found that found that breeding occurred in a rehabilitated and released population of mugger crocodiles four years after the first release. Survival (1 study): One study in India found that seven of eight rehabilitated and released mugger crocodiles survived for at least 1–4 years after release. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3743https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3743Tue, 14 Dec 2021 10:48:01 +0000Collected Evidence: Collected Evidence: Rehabilitate and release injured or accidentally caught individuals: Tuatara We found no studies that evaluated the effects of rehabilitating and releasing injured or accidentally caught tuatara on their populations. ‘We found no studies’ means that we have not yet found any studies that have directly evaluated 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%2F3744https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3744Tue, 14 Dec 2021 11:10:19 +0000Collected Evidence: Collected Evidence: Breed reptiles in captivity: Tortoises, terrapins, side-necked & softshell turtles Twenty-eight studies evaluated the effects of breeding tortoises, terrapins, side-necked & softshell turtles in captivity. Twelve studies were in the USA, four were in the Seychelles, two were in Madagascar, two were in an unknown location and one was in each of the Galápagos, Germany, Austria, Jersey, Italy, India, China and Myanmar. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (28 STUDIES) Abundance (5 studies): Four studies (including one replicated study) in Madagascar, the Seychelles and the USA reported that captive breeding programmes produced 255 ploughshare tortoises, 40 and 140 giant tortoises, 75 juvenile radiated tortoises and 94 Madagascar big-headed turtle hatchlings. One study also reported that the captive population grew each year. One replicated study in Myanmar reported that the number of Burmese star tortoise hatchlings produced in captivity increased from 168 to over 2,000 over eight years. Reproductive success (24 studies): Eighteen studies (including one replicated, controlled, before-and-after study) in the USA, the Galápagos, Germany, Austria, the Seychelles, Italy, India, China and an unknown location reported that females produced 0–25 clutches of 1–26 eggs, 65–78 eggs each/year or a total of 10–170 eggs. Three of these studies reported hatching success of 52–100%, four reported hatching success of 23–71%, three reported hatching success of 0–66%, 0–81% or 0–100% and six reported hatching success of 0–43% or 0–3 hatchings/clutch. One other study from the Seychelles reported that 0–75% of eggs from one of two mud turtle species hatched successfully. One of the studies also found that three of five eggs produced by a captive-bred tortoise hatched successfully. Two studies in Jersey and the Seychelles reported that only 3 Malagasy Flat-tailed tortoise eggs and 3–18 mud turtle eggs hatched successfully over 11–12 years. One study in Madagascar reported that most Madagascar big-headed turtle eggs laid in captivity were infertile. One study in the USA reported that hatching success of 2nd generation captive desert tortoises was 20–83%, whereas success for 3rd generation tortoises was 0–43%. One study in the USA found that hatching success for captive Bourret’s box turtle eggs was higher when incubated at 26–27°C compared to 28–29°C. Survival (7 studies): Three studies (including one replicated study) in the USA, Austria and an unknown location reported that 2–4 captive-bred tortoises or turtles survived for at least 28 weeks to two years. One replicated study in Italy reported that all captive-bred spider tortoises survived to adult size. Two studies in the USA and Jersey reported that 25–30% of captive-bred tortoises died within 12–18 months. One study in the Seychelles reported that 70% of captive-bred mud turtles died during hatching BEHAVIOUR (0 STUDIES) OTHER (1 STUDY) Offspring sex ratio (1 study): One study in the USA reported that a captive breeding programme of radiated tortoises produced 67 females and eight males. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3746https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3746Tue, 14 Dec 2021 11:18:05 +0000Collected Evidence: Collected Evidence: Breed reptiles in captivity: Snakes – Elapids Four studies evaluated the effects of breeding elapid snakes in captivity. Three studies were in Australia and one was in India. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (4 STUDIES) Reproductive success (4 studies): Three studies in Australia and India reported that 1–4 females elapid snakes produced clutches of eggs in captivity, with 26–93% hatching successfully. One study in Australia reported that two generations of death adders produced litters of 17–25 young in captivity, though 20 were still born. Survival (2 studies): Two studies in Australia and India reported that two western brown hatchlings survived 2–3 years and 87% of king cobra hatchlings survived one year in captivity. Condition (1 study): One study in Australia reported that eight of 15 captive-bred western brown snake hatchlings lacked one or both eyes. BEHAVIOUR (0 STUDIES) OTHER (1 STUDY) Offspring sex ratio (1 study): One study in Australia reported that 55% of captive-bred Australian death adders were female. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3750https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3750Tue, 14 Dec 2021 13:27:14 +0000Collected Evidence: Collected Evidence: Breed reptiles in captivity: Snakes – Vipers Thirteen studies evaluated the effects of breeding vipers in captivity. Nine studies were in the USA, three were in unknown locations and one was in Columbia. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (13 STUDIES) Reproductive success (13 studies): Thirteen studies in the USA, Columbia and unknown locations reported that 1–4 female vipers, including three captive-bred offsping, produced litters of 1–18 live young or clutches of 1–26 eggs with hatching success of 63–81%. One study also reported that none of three Chocoan bushmaster eggs that were removed and incubated artificially fully developed. Survival (5 studies): Three studies in the USA and one in an unknown location reported that of 10–49 captive-bred young snakes, 1–9 died soon after birth or within three months. One study also reported that one pair of adult adders died shortly after arriving in captivity. One study in an unknown location reported that four captive-bred Radde’s vipers survived for at least eight months Condition (1 study): One study in an unknown location reported that two of 10 captive-bred Nikolsky's adders had some physical deformities. BEHAVIOUR (0 STUDIES) OTHER (2 STUDIES) Offspring sex ratio (2 studies): Two studies in the USA and an unknown location reported that the sex ratio of captive-bred lower California rattlesnakes was 2:12 and Russell's vipers was 8:6 females to males. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3753https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3753Tue, 14 Dec 2021 13:32:11 +0000Collected Evidence: Collected Evidence: Breed reptiles in captivity: Tuatara One study evaluated the effects of breeding tuatara in captivity. This study was in New Zealand. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Reproductive success (1 study): One replicated study in New Zealand reported that hatching success of eggs laid in captivity by tuatara was around 50%. The study also found that the first clutches were laid 2–8 years after tuatara were brought into captivity. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3758https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3758Tue, 14 Dec 2021 15:42:24 +0000Collected Evidence: Collected Evidence: Use artificial insemination One study evaluated the effects of using artificial insemination on reptile populations. This study was in New Zealand. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Reproductive success (1 study): One replicated study in New Zealand found that none of 10 artificially inseminated McCann’s skinks gave birth within a year of insemination, though around five were gravid after nine months. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3759https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3759Tue, 14 Dec 2021 15:47:24 +0000Collected Evidence: Collected Evidence: Freeze sperm or eggs for future use We found no studies that evaluated the effects of freezing sperm or eggs for future use on reptile populations. ‘We found no studies’ means that we have not yet found any studies that have directly evaluated 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%2F3760https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3760Tue, 14 Dec 2021 16:06:26 +0000Collected Evidence: Collected Evidence: Maintain wild-caught, gravid females in captivity during gestation Seven studies evaluated the effects on reptile populations of maintaining wild-caught, gravid females in captivity during gestation. Two studies were in the USA and New Zealand and one was in each of Japan, Iran and Mexico. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (7 STUDIES) Reproductive success (7 studies): Five replicated studies in the USA, Japan, Iran and Mexico found that varying numbers of wild-caught snakes and lizards gave birth to live young or laid eggs that hatched successfully in captivity. One study also found that eggs laid in artificial nest chambers had higher hatching success than those laid outside of the chambers. One study in New Zealand found mixed effects of providing different basking conditions on the number of McCann’s skinks and common geckos that gave birth successfully. One controlled study in New Zealand found that McCann’s skinks in captivity that were treated for mites completed pregnancy more often and produced more viable offspring compared to skinks not treated. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3766https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3766Tue, 14 Dec 2021 17:16:10 +0000Collected Evidence: Collected Evidence: Use hormones and/or other drugs during captive-breeding programmes to induce reproduction/birth Nine studies evaluated the effects on reptile populations of using hormones and/or other drugs during captive-breeding programmes to induce reproduction/birth. Three studies were in each of the USA and New Zealand and one study was in each of the Netherlands, China and Japan. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (9 STUDIES) Reproductive success (9 studies): Three of four replicated, controlled studies (including one before-and-after study) in the USA and China found that plains gartersnakes, eastern painted turtles and red-eared sliders induced with oxytocin produced a similar percentage of live young compared to individuals that were not induced and laid eggs with similar hatching success or laid a similar number of eggs compared to what was observed in wild nests. The other study found that 25% of eggs from hormone-injected (luteinizing hormone and gonadotropin) four-eyed turtles were fertile, compared to 7–52% for females that were not injected or injected with a saline solution. One study also found mixed effects of different combinations of hormones and other drugs on inducing 13 turtle species. Five studies (including one before-and-after study) in the Netherlands, New Zealand and Japan found that oxytocin, arginine vasotocin and follicle-stimulating hormone induced egg laying/birth in yellow-headed box turtles, tuatara and common geckos or ovulation in hawksbill turtles. One study also found that only one yellow-headed box turtle female produced fertile eggs. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3767https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3767Tue, 14 Dec 2021 17:27:59 +0000Collected Evidence: Collected Evidence: Release captive-bred reptiles into the wild: Sea turtles Three studies evaluated the effects of releasing captive-bred sea turtles into the wild. Two studies were in the Gulf of Mexico and one was in the Caribbean. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (3 STUDIES) Reproductive success (1 study): One replicated study in the Caribbean found that eight of over 30,000 captive-bred green turtles released into the wild (around 15,000 reared to one year or more in captivity) were observed nesting and two produced clutches of >100 eggs with hatching success of 63% and 88%. Survival (3 studies): Three replicated studies in the Gulf of Mexico and the Caribbean reported that following releases of captive-bred Kemp's ridley turtles and green turtles into the wild, 120–606 of 22,000–30,000 turtles survived for 1–19 years after release. Condition (1 study): One replicated study in the Gulf of Mexico found that captive-bred Kemp's ridley turtles released into the wild grew by 19–59 cm over 1–9 years. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3768https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3768Tue, 14 Dec 2021 17:46:32 +0000Collected Evidence: Collected Evidence: Release captive-bred reptiles into the wild: Tortoises, terrapins, side-necked & softshell turtles Fourteen studies evaluated the effects of releasing captive-bred tortoises terrapins, side-necked & softshell turtles into the wild. Five studies were in the USA, three were in Italy, two were in the Seychelles, and one was in each of Madagascar, Australia and Spain and Minorca and one was global. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (13 STUDIES) Abundance (1 study): One global review found that when using recruitment to the adult population as a measure of success, 32% of reptile translocations/releases (releases of captive individuals were 7% of total projects) were successful. Occupancy/range (1 study): One review in Australia found that two of three releases of captive-bred Western swamp tortoises were classified as successful. Reproductive success (2 studies): Two studies (including one replicated study) in Italy reported evidence of a gravid female and successful reproduction following release of captive-bred European pond turtles. Survival (11 studies): Six of nine studies (including two replicated, controlled studies) in Madagascar, the Seychelles, the USA and Italy reported that 66–100% of 5–80 captive-bred tortoises and turtles released into the wild survived over monitoring periods of six months to two years. Two studies reported that 16–20% of 5 and 246 individuals survived over two years. The other study reported that some of over 250 individuals (number not given) were recaptured over a year of monitoring. One study also found captive-bred alligator snapping turtles that were older at their time of release had higher survival than younger turtles. One replicated study in Italy found that annual survival of released captive-bred European pond turtles was 67–91%. One replicated study in Spain and Minorca found that survival of captive-bred Hermann’s tortoises was higher after three years after release into the wild compared to 1–2 years after release. The study also found that after three years, survival of released tortoises was similar to that of wild tortoises in one population, but lower in a second population. Condition (2 studies): One of two controlled studies (including one replicated study) in the USA found that released captive-bred juvenile alligator snapping turtles grew at a similar rate and achieved higher body condition than juveniles that remained in captivity. The other study found that released alligator snapping turtles had similar body conditions compared to individuals that remained in captivity. BEHAVIOUR (1 STUDY) Behaviour change (1 study): One randomized study in the USA found that captive-bred Blanding’s turtles released into open water habitat had larger home ranges than those released into places dominated by cattail or willows. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3770https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3770Wed, 15 Dec 2021 11:07:11 +0000Collected Evidence: Collected Evidence: Release captive-bred reptiles into the wild: Snakes & lizards Ten studies evaluated the effects on reptile populations of releasing captive-bred snakes and lizards into the wild. Three studies were in New Zealand, two were in the USA and one was in each of the Galápagos, Spain, Australia and Canada and one was global. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (10 STUDIES) Abundance (2 studies): One global review found that when using recruitment to the adult population as a measure of success, 32% of reptile releases (releases of captive individuals were 7% of total projects) were successful. One review in New Zealand found that 13% of lizard releases (some involving captive-bred animals) found evidence of populations growth Reproductive success (3 studies): Three studies (including two reviews) in the USA and New Zealand found evidence of breeding following release in one of two captive-bred populations of cornsnakes, one captive-bred population of Otago skinks and in at least 16 lizard mitigation translocations, some of which involved captive-bred animals. Survival (9 studies): One replicated, controlled study in Spain found that released large psammodromus lizards had similar annual survival compared to resident lizards. Two of six studies (including one replicated study and two reviews) in the USA, Australia, New Zealand and Canada reported that 13% of 40 indigo snakes were re-sighted at least once during 5–8 years following release or that 58% of 12 Otago skinks survived at least 18 months. Two studies found that zero of nine and 27 individuals survived more than 143 days or beyond their first hibernation. The other two studies found that one of two and five of 53 releases (only some of which involved captive-bred animals) failed completely (no individuals survived). One study in New Zealand found that survival of captive-bred Otago skinks released into an enclosure was higher when mice had been eradicated compared to when skinks were released in the presence of mice. One replicated study in the Galápagos found that while releases were ongoing over a decade (183 released in total), 17–32 Galápagos land iguanas were recaptured each year. Condition (1 study): One controlled study in New Zealand found that body condition of captive-reared Otago skinks was higher than wild skinks, but sprint speed was lower. BEHAVIOUR (1 STUDY) Behaviour change (1 study): One replicated, controlled study in Spain found that released large psammodromus lizards moved between habitat fragments more frequently than resident lizards but showed similar behaviour in three other measures. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3771https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3771Wed, 15 Dec 2021 11:29:15 +0000Collected Evidence: Collected Evidence: Release captive-bred reptiles into the wild: Crocodilians Four studies evaluated the effects of releasing captive-bred crocodilians into the wild. Two studies were in China, one was in South Africa and one was a global review. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (4 STUDIES) Abundance (2 studies): One global review found that when using recruitment to the adult population as a measure of success, 32% of reptile translocations/releases (releases of captive individuals were 7% of total projects) were successful. One study in South Africa reported that following releases of captive-bred Nile crocodiles, wild populations increased in size over 30 years, but then declined in the subsequent 15 years. Reproduction (2 studies): Two studies (one replicated) in China reported that breeding or nesting was observed within four years of releasing captive-bred Chinese alligators. Survival (1 study): One study in China reported that of nine captive-bred Chinese alligators, three survived for nine years and six survived for at least one year following release. BEHAVIOUR (1 STUDY) Use (1 study): One replicated study in China reported that after 10 years of releases of captive bred Chinese alligators to an area that had historically been occupied, 56% of constructed ponds were occupied. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3772https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3772Wed, 15 Dec 2021 11:53:57 +0000Collected Evidence: Collected Evidence: Release captive-bred reptiles into the wild: Tuatara Two studies evaluated the effects of releasing captive-bred tuatara into the wild. One study was in New Zealand and one was a global review. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Abundance (1 study): One global review found that when using recruitment to the adult population as a measure of success, 32% of reptile translocations/releases (releases of captive individuals were 7% of total projects) were successful. Condition (1 study): One study in New Zealand found that tuatara reared close to the release site had higher growth, but similar body condition compared to individuals reared in a warmer climate. BEHAVIOUR (1 STUDY) Behaviour change (1 studies): One study in New Zealand found that tuatara reared close to the release site had similar home range sizes and post-release dispersal compared to individuals reared in a warmer climate. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3773https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3773Wed, 15 Dec 2021 12:02:09 +0000Collected Evidence: Collected Evidence: Use holding pens or enclosures at release site prior to release of captive-bred reptiles Two studies evaluated the effects on reptile populations of using holding pens or enclosures at release sites prior to release of captive-bred reptiles. Both studies were in the USA. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (2 STUDIES) Survival (2 studies): Two controlled studies (including one replicated study) in the USA found that survival of captive-bred smooth green snakes and desert tortoises held in pens before release was similar over 3–5 months or 2–3 years compared to individuals released directly. BEHAVIOUR (1 STUDY) Behaviour change (1 study): One controlled study in the USA found that movement of smooth green snakes held in pens before release was similar compared to snakes that were released directly. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3774https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3774Wed, 15 Dec 2021 12:04:46 +0000Collected Evidence: Collected Evidence: Head-start wild-caught reptiles for release: Sea turtles Seven studies evaluated the effects of head-starting wild-caught sea turtles for release. Two studies were in the Caribbean Sea and one was in each of the Torres Strait, northern Australia, the Gulf of Mexico, Japan, the USA and Thailand. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (6 STUDIES) Abundance (1 studies): One replicated, before-and-after study in the USA found that over the course of a 37-year head-start programme, the number of kemp’s ridley nests laid on the Texas coastline increased from near zero to 119. Reproductive success (2 studies): Two studies (including one replicated, before-and-after study) in Mexico and the USA found that all 11 head-started Kemp’s ridley turtles bred in the wild following release and head-started turtles that were allowed to crawl to the sea before recapture began laying nests on their beach of origin 10–12 years after release. Survival (4 studies): One of four studies (including two replicated and two controlled studies) in the Caribbean Sea, Torres Strait near Australia, Gulf of Mexico and Japan reported that all 11 head-started Kemp’s ridley turtles survived at least 11–19 years following release. Two of the studies reported that 1–16% of sea turtles were recaptured 10–27 month or 0.5–13 months following release. The other study found that four head-started hawksbill turtles survived at least 4–9 days, and one survived at least 10 months following release. Condition (1 study): One replicated study in Thailand found mixed effects of tank depth on growth rate, size and body condition of green turtles during a head-starting programme and no effect of feed type. BEHAVIOUR (2 STUDIES) Use (1 study): One replicated study in the Caribbean Sea reported that one head-started green turtle travelled 2,300 km from its release location, whereas other recaptures were within 1–14 km of the release site. Behaviour change (1 study): One replicated study in the Caribbean Sea found mixed effects on swimming behaviour of released head-started loggerhead turtles at 1.5 years old compared to 2.5 years old. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3775https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3775Wed, 15 Dec 2021 12:21:11 +0000Collected Evidence: Collected Evidence: Head-start wild-caught reptiles for release: Tortoises, terrapins, side-necked & softshell turtles Eighteen studies evaluated the effects of head-starting wild-caught tortoises, terrapins, side-necked and softshell turtles for release. Thirteen studies were in the USA, two were in Venezuela and one was in each of the Galápagos, Poland and Madagascar. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (18 STUDIES) Abundance (1 study): One controlled study in Venezuela found that 57% of captured giant sideneck river turtles were head-started individuals. Survival (13 studies): Two of three studies (including one replicated, controlled study) in the USA and Poland found that head-started European pond turtles and desert tortoises had similar survival compared to wild turtles or hatchlings released directly into the wild. The other study found that head-started northern redbelly turtles had higher survival than wild hatchling turtles. This study also found that in the first year of release, larger head-started turtles had higher survival, but in year 2–3 survival was similar for all sizes. Four of 12 studies (including nine replicated studies) in the Galápago, the USA, Madagascar and Venezuela reported that 50–100% of head-started individuals survived for three months to 1–5 years after release. Three of the studies reported that 6–43% of individuals survived for 1–3 years. Two of the studies reported that six of six, two of 10 and nine of 10 radio-tracked individuals survived 3–12 months. Two of the studies reported that annual survival was 80–100% or 3–100% in the year following release but 82–100% in subsequent years. The other study reported that some giant sideneck river turtles survived up to 14 years. Two studies also reported that survival during the captive phase was 91–100%. One study also found that more tortoises head-started in outdoor seaside pens died than did those from indoor pens. One replicated, controlled study in Venezuela found that survival of Arrau turtles during the captive phase was lower for turtles from relocated nests compared to those from nests that were not moved. Condition (5 studies): One of two replicated studies in the USA found that two-year-old head-started gopher tortoises were larger at their time of release than two-year-old tortoises released in to the wild directly after hatching. The other study found that Agassiz’s desert tortoise hatchlings grew more slowly in captivity than tortoises in the wild. Two studies (including one replicated study) in the USA found that Alabama red-bellied cooters and wood turtles grew during 12–16 months in captivity, and wood turtles showed no signs of shell malformation. One controlled study in Venezuela found that the size distribution of released head-started giant sideneck river turtles was similar to that of wild turtles when newly released individuals were excluded. BEHAVIOUR (1 STUDY) Use (1 study): One study in the USA found that 81% of desert tortoises established home ranges within 13 days of release. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3776https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3776Wed, 15 Dec 2021 12:31:41 +0000Collected Evidence: Collected Evidence: Head-start wild-caught reptiles for release: Snakes & lizards Nine studies evaluated the effects of head-starting wild-caught snakes and lizards for release. Five studies were in the USA, two were in Puerto Rico and one was in each of the Cayman Islands and Jamaica. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (9 STUDIES) Abundance (2 studies): Two studies (including one before-and-after and one replicated study) in Jamaica and the Cayman Islands reported that the number of Jamaican iguanas found in the wild was higher after 23 years of head-starting and releasing compared to at the start of the programme and that there was a stable population of blue iguanas over four years during ongoing releases of head-started individuals. Reproductive success (4 studies): Four studies (including two replicated studies) in Jamaica, Puerto Rico and the USA reported successful reproduction following release of head-started Jamaican iguanas (but not for 16 years) and Mona Island iguanas, and that timber rattlesnakes copulated or participated in pre-copulatory behaviour. One study also reported that 88–90% of Mona Island iguana eggs hatched successfully. Survival (8 studies): Two of three controlled studies (including one replicated, randomized study) in the USA found that head-started plains gartersnakes and common water snakes were recaptured a similar number of times or had similar survival compared to resident snakes. The other study found that head-started northern water snakes had lower survival following release than resident snakes. One study also found that 76% of snakes survived the captive phase of head-starting. Three studies (including two replicated studies) in the USA and Puerto Rico reported that 22–40% of timber rattlesnakes or Mona Island iguanas survived for monitoring periods of eight months to six years. One replicated study in the USA found that head-started eastern massasaugas released in summer had higher survival than snakes released in autumn. One before-and-after study in Jamaica reported that 16% of Jamaican iguanas died during the captive phase of head-starting. Condition (5 studies): Two of three controlled studies (including one replicated, randomized study) in the USA found that head-started northern water snakes and common water snakes grew more slowly than resident snakes. The other study found that head-started plains gartersnakes had similar growth rates to resident snakes. One study also found that head-started common water snakes had similar body condition to resident snakes. One controlled study in Puerto Rico found that body condition of head-started Mona Island iguanas was higher than wild iguanas before release, but similar at their first recapture after release. One replicated study in the USA found that more head-started eastern massasaugas released in summer gained weight before hibernation than snakes released in autumn. BEHAVIOUR (3 STUDIES) Behaviour change (3 studies): One of three studies (including one replicated, randomized, controlled study) in the USA found that head-started common water snakes showed similar behaviour to residents across a range of behaviour measures. One of the studies found that head-started northern water snakes had smaller home ranges and showed less surface activity than resident snakes. The other study found that head-started eastern massasaugas released in summer had larger home ranges than snakes released in autumn. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3777https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3777Wed, 15 Dec 2021 13:03:25 +0000Collected Evidence: Collected Evidence: Head-start wild-caught reptiles for release: Crocodilians Seven studies evaluated the effects of head-starting wild-caught crocodilians for release. Two studies were in each of the Philippines and Nepal and one study was in each of Zimbabwe, Venezuela and Argentina. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (7 STUDIES) Abundance (2 studies): Two studies (including one replicated study) in the Philippines and Nepal reported that following releases of head-started crocodiles or gharials, wild populations increased in size over 8–9 years. Reproductive success (2 studies): One replicated study in Argentina reported that released head-started broad-snouted caimans had similar clutch sizes and hatching success compared to non-head-started caiman. One replicated study in Nepal reported successful reproduction in all four rivers where head-started gharials were released. Survival (5 studies): Three studies (including one replicated, controlled study) in Venezuela, the Philippines and Nepal reported that 88% of head-started Orinoco crocodiles survived 8–12 months and 53% of Philippine crocodiles or gharials survived for one year following release. One study also found that survival of Philippine crocodile hatchlings during the captive phase of head-starting was higher than for non-head-started hatchlings in the wild. One replicated study in Argentina reported that at least five released head-started broad-snouted caimans survived 9–10 years. One replicated study in Zimbabwe found that 38% of released head-started Nile crocodiles were recaptured at least once over four years. This study also found that hatching success of Nile crocodile eggs in the head-start programme was 74%, and that survival of hatchlings during the captive phase was lowest during the first year. Condition (1 studies): One study in Venezuela found that released head-started Orinoco crocodiles grew at a similar rate to resident juvenile crocodiles. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3778https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3778Wed, 15 Dec 2021 13:26:54 +0000Collected Evidence: Collected Evidence: Head-start wild-caught reptiles for release: Tuatara Two studies evaluated the effects of head-starting wild-caught tuatara for release. Both studies were in New Zealand. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (2 STUDIES) Survival (2 studies): One study in New Zealand reported that 67–70% of head-started tuatara survived over monitoring periods of 9–11 months. One study in New Zealand found that 56% of head-started tuatara were recaptured over six years following release. Condition (1 studies): One study in New Zealand reported that head-started tuatara increased in weight by around 100 g during the five years following release. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3779https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3779Wed, 15 Dec 2021 13:42:27 +0000Collected Evidence: Collected Evidence: Release reptiles born/hatched in captivity from wild-collected eggs/wild-caught females without rearing Five studies evaluated the effect on reptile populations of releasing reptiles born/hatched in captivity from wild-collected eggs/wild-caught females without rearing. Four studies were in the USA and one was in Australia. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (5 STUDIES) Reproductive success (1 study): One replicated, controlled study in the USA found that for plains gartersnakes released as newborns, two of over 350 released snakes were found to be gravid two years after release. Survival (5 studies): One before-and-after study in the USA found that survival of captive-born desert tortoises released as hatchlings was similar over six months compared to hatchlings that were head-started in indoor or outdoor enclosures. One replicated, controlled study in the USA found that alligator hatchlings released into their mother’s home range had higher survival than those released outside her home range. Three replicated studies (including one controlled study) in Australia and the USA found that 11% of Murray short-necked turtles and 7% of plains gartersnakes survived for 1–3 years after release, and first year survival of gopher tortoise hatchlings released into a predator proof enclosure was around 30%. Condition (2 studies): One before-and-after study in the USA found that captive-born desert tortoises released as hatchlings grew more slowly over six months than hatchlings head-started in an indoor enclosure. One replicated, controlled study in the USA found mixed effects on growth of alligator hatchlings released inside or outside of their mother’s home range compared to wild hatchlings. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3780https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3780Wed, 15 Dec 2021 14:31:38 +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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