Collected Evidence: Collected Evidence: Relocate nests/eggs to a hatchery: Sea turtles Twenty-two studies evaluated the effects on sea turtle populations of relocating nests/eggs to a hatchery. Four studies were in each of Malaysia, Mexico and Costa Rica, three studies were in Brazil, two studies were in Cape Verde and one study was in each of the USA, Turkey, Greece, Indonesia and Mauritius. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (22 STUDIES) Reproductive success (19 studies): Four of 10 studies (including seven replicated, controlled studies) in Brazil, Mexico, Greece, Cape Verde, Costa Rica, Indonesia found mixed effects on hatching success in sea turtle nests relocated to hatcheries compared to natural nests. Three studies found that sea turtle nests relocated to hatcheries had similar hatching or emergence success compared to natural nests, and specifically those laid in safe locations or those that were camoflaged. Two studies found that nests relocated to hatcheries had higher hatching success than natural nests, and in one case all the natural nests were predated. The other study found that nests relocated to a hatchery had lower hatching success than natural nests in six of seven seasons. Two of the studies also found that fewer nests relocated to hatcheries were lost to erosion or predation compared to natural nests. One of the studies also found that hatching success was similar following immediate relocation compared to delayed but careful relocation. Four studies (including one replicated, randomized study) in Malaysia, Mexico, Costa Rica and Mauritius reported that hatching success of sea turtle eggs and nests relocated to hatcheries ranged from 35–78%. One study also found that hatching success was not affected by the number of eggs in the nest. Three studies (including one randomized replicated study) in the USA, Malaysia and Mexico found that sea turtle nests relocated to hatcheries had similar hatching success compared to those relocated for artificial incubation. One study also found that handling eggs during the first five days did not affect hatching success. One replicated, controlled, before-and-after study in Costa Rica found that leatherback turtle nests relocated to a hatchery or to other parts of the beach (results combined) had similar hatching success compared to natural nests. One replicated, controlled study in Turkey found that hatching success was similar if nests were relocated 0–18 h after laying. Survival (2 studies): Two studies in Costa Rica and Mauritius found that 77% of olive ridley turtle hatchlings and 89% of green turtle hatchlings from hatcheries successfully reached the ocean. Condition (4 studies): Two randomized studies (including one replicated, controlled, before-and-after study) in Mexico found that relocating olive ridley turtle nests to a hatchery had mixed effects on size or size, movement and condition of hatchlings compare to hatchlings that were artificially incubated or from natural nests. One study also found that hatchery hatchlings had higher stress hormone levels than hatchlings from natural nests after emergence, and a different stress response to reaching the ocean compared to hatchlings from natural nests. One replicated, randomized study in Malaysia found that green turtle hatchlings released from hatcheries immediately after emergence moved faster than hatchlings held in the hatchery for 1–6 hours and had better body condition than hatchlings held for 3–6 hours. One replicated study in Malaysia found that excavating green turtle hatchlings in a hatchery immediately after the main clutch emerged resulted in better movement and body condition compared to hatchings excavated five days later. BEHAVIOUR (0 STUDIES) OTHER (1 STUDY) Offspring sex ratio (1 study): One replicated, randomized study in Malaysia found that all but 1 of 169 leatherback turtle eggs relocated to a hatchery produced female hatchlings. Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3785https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3785Wed, 15 Dec 2021 15:39:26 +0000Collected Evidence: Collected Evidence: Relocate nests/eggs to a hatchery: Tortoises, terrapins, side-necked & softshell turtles Two studies evaluated the effects on tortoise, terrapin, side-necked and softshell turtle populations of relocating nests/eggs to a hatchery. One study was in Costa Rica and Venezuela. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (2 STUDIES) Reproductive success (2 studies): One replicated, controlled study in Venezuela found that yellow-headed sideneck turtle eggs relocated to a hatchery had higher hatching success than both natural nests and artificially incubated eggs. One study in Costa Rica reported that 80% of Nicaraguan slider eggs in a hatchery hatched successfully. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3787https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3787Wed, 15 Dec 2021 16:31:59 +0000Collected Evidence: Collected Evidence: Relocate nests/eggs to a hatchery: Snakes & lizards We found no studies that evaluated the effects of relocating nests/eggs to a hatchery on snake and lizard 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%2Fconservationevidencejournal.com%2Factions%2F3792https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3792Wed, 15 Dec 2021 16:41:29 +0000Collected Evidence: Collected Evidence: Relocate nests/eggs to a hatchery: Crocodilians We found no studies that evaluated the effects of relocating nests/eggs to a hatchery on crocodilian 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%2Fconservationevidencejournal.com%2Factions%2F3793https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3793Wed, 15 Dec 2021 16:57:18 +0000Collected Evidence: Collected Evidence: Relocate nests/eggs to a hatchery: Tuatara We found no studies that evaluated the effects of relocating nests/eggs to a hatchery on tuatara 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%2Fconservationevidencejournal.com%2Factions%2F3794https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3794Wed, 15 Dec 2021 16:59:42 +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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