Conservation Evidence: Evidence Data

Collected Evidence: Collected Evidence: Relocate nests/eggs for artificial incubation: Sea turtles Fifteen studies evaluated the effects of relocating nests/eggs for artificial incubation on sea turtle populations. Three studies were in Suriname and the USA, two were in each of Costa Rica, Malaysia, the Dominican Republic and Mexico and one was in the Cayman Islands. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (12 STUDIES) Reproductive success (12 studies): One of four controlled studies (including three replicated studies) in Suriname, the Dominican Republic, the USA found that kemp’s ridley nests relocated for artificial incubation had higher hatching success than natural nests. One of the studies found that leatherback turtle nests relocated for artificial incubation had lower hatching success than natural nests. One of the studies found that hawksbill turtle nests relocated for artificial incubation had similar hatching success compared to natural nests. The other study found that hatching success of leatherback and green turtle nests relocated for artificially incubation was similar to natural nests above the high tide line and may have been higher than for natural nests washed over by sea swells. This study also found higher embryo mortality in artificially incubated nests compared to natural nests. Three studies (including one randomized, controlled study) in the USA, Mexico and Malaysia found that loggerhead, olive ridley and leatherback turtle nests relocated for artificial incubation had similar hatching success compared to nests relocated to an on-beach hatchery. One study also found that careful handling of eggs during the first five days of incubation did not affect hatching success. Four studies (including one replicated study) in Surinam, Ascension Island and Costa Rica, the Cayman Islands, the USA and Mexico reported that hatching success of green, loggerhead and olive ridley turtle nests relocated for artificial incubation varied from 26% to >90%. One study also reported that hatching success from two trials was 30% and 58% in foam-packed boxes and 26% and 48% in sand-packed boxes. One study also reported that hatching success was 60–89% in 14 of 18 years. One replicated, randomized, controlled study in Costa Rica found that olive ridley turtle eggs artificially incubated in low oxygen conditions had lower hatching success than those in normal oxygen conditions. Condition (2 studies): One replicated, controlled study in Suriname found that leatherback and green turtle nests relocated for artificial incubation had more instances of embryo deformities than natural nests. One randomized, controlled study in Mexico found that relocating olive ridley nests for artificial incubation had mixed effects on hatchling size and movement compared to those relocated to an on-beach hatchery. BEHAVIOUR (0 STUDIES) OTHER (3 STUDIES) Offspring sex ratio (3 studies): Three replicated studies (including two controlled studies) in Suriname and Malaysia found that green turtle and leatherback turtle nests relocated for artificial incubation produced fewer female hatchlings than eggs from natural nests and/or that all sexed hatchlings that were artificially incubated were male. Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3795https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3795Wed, 15 Dec 2021 17:02:44 +0000Collected Evidence: Collected Evidence: Relocate nests/eggs for artificial incubation: Tortoises, terrapins, side-necked & softshell turtles Seventeen studies evaluated the effects of relocating nests/eggs for artificial incubation on tortoise, terrapin, side-necked & softshell turtle Ten studies were in the USA, two were in each of the Galápagos and China and one was in each of Brazil, Venezuela and Thailand. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (17 STUDIES) Reproductive success (16 studies): Two of three replicated controlled studies (including one randomized study) in Brazil, Venezuela and the USA found that Hilaire’s side-necked turtle and bog turtle nests relocated for artificial incubation had higher hatching success, or likely had higher success, than natural nests.The other study found that yellow-headed sideneck turtle nests relocated for artificial incubation had lower hatching success than natural nests and nests moved to an on-beach hatchery. One replicated study in the Galápagos reported that hatching success of five subspecies of giant tortoise nests relocated for artificial incubation was 35–100%, compared to 76–85% for natural nests of two sub species. Six of eight studies (including four replicated studies) in the USA and China reported that hatching success for artificially incubated eggs, including eggs recovered from road-killed turtles, was 60–97%, or that 314 hatchlings emerged, and 14 eggs did not hatch. One study also found that eggs collected from the wild had similar hatching success compared to oxytocin-induced eggs. The other two studies reported that hatching success of eggs or clutches was 39–54%. One replicated study in the Galápagos reported that hatching success of giant tortoise nests relocated for artificial incubation may have been higher for nests relocated longer after laying. One replicated study in the USA found that high levels of CO2 during artificial incubation of pond slider and Mississippi map turtle eggs resulted in lower hatching success compared to low CO2. One replicated, randomized study in China found that hatching success of artificially incubated Chinese three-keeled pond turtle eggs was similar across all temperatures tested. One randomized study in the USA found that hatching success of artificially incubated snapping turtle eggs was highest at intermediate levels of soil moisture. Survival (3 studies): Two studies (including one replicated study) in the USA reported that after relocating smooth softshell turtle and gopher tortoise nests for artificial incubation, two of 314 and three of 36 hatchlings died soon after emergence. One randomized study in the USA found that survival of artificially incubated snapping turtle hatchlings was lower at high soil moisture levels compared to intermediate moisture levels. Condition (4 studies): One replicated, randomized, controlled study in Brazil found that Hilaire’s side-necked turtle nests relocated for artificial incubation produced heavier hatchlings that were larger in four of five measures compared to hatchlings from natural nests. Two replicated studies (including one randomized study) in China found that modifying incubation temperatures of Chinese three-keeled pond turtle or Asian yellow pond turtle eggs had mixed effects on hatchling size and mobility or different effects on growth depending on the population eggs were sourced from. One replicated study in Thailand found that artificially incubating snail-eating turtle eggs at higher temperatures resulted in more embryos with physical deformities. BEHAVIOUR (0 STUDIES) OTHER (1 STUDY) Offspring sex ratio (1 study): One replicated study in the USA found that high levels of CO2 during artificial incubation of pond slider and Mississippi map turtle eggs resulted in a lower proportion of male hatchlings compared to low CO2 Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3796https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3796Wed, 15 Dec 2021 17:42:36 +0000Collected Evidence: Collected Evidence: Relocate nests/eggs for artificial incubation: Snakes Four studies evaluated the effects of relocating nests/eggs for artificial incubation on snake populations. Two studies were in Australia and one was in each of Japan and China. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (4 STUDIES) Reproductive success (4 studies): Two studies in Australia reported that 87% of carpet python eggs and 83% of brown tree snake eggs hatched successfully following artificial incubation. One study also reported that zero of 10 artificially incubated Oenpelli python eggs hatched. One study in Japan reported that 265 habu eggs hatched successfully following artificial incubation. One replicated, randomized study in China found that hatching success of artificially incubated stripe-tailed ratsnake eggs was lowest at the coolest and warmest temperatures tested. BEHAVIOUR (0 STUDIES) OTHER (1 STUDY) Offspring sex ratio (1 study): One study in Japan reported that artificially incubated habu eggs produced offspring with an even sex ratio. Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3797https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3797Wed, 15 Dec 2021 18:19:49 +0000Collected Evidence: Collected Evidence: Relocate nests/eggs for artificial incubation: Lizards Fifteen studies evaluated the effects of relocating nests/eggs for artificial incubation on lizard populations. Five studies were in China, two were in each of India, Spain, the USA and New Zealand and one was in each of Namibia and Taiwan. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (15 STUDIES) Reproductive success (12 studies): One replicated, controlled study in Namibia found that artificially incubated white-throated savanna monitor eggs had higher hatching success than eggs in natural nests. Three of four studies (including one replicated, controlled study) in the USA, Spain, Taiwan and China reported hatching success of 56–96% for artificially incubated eggs from wild lizards. The other study reported that hatching success varied between 11–76%. One replicated, randomized study in India found that hatching success of artificially incubated garden lizard eggs was lower for eggs incubated in cotton wool compared to those incubated in soil or sand. One replicated study in the USA found that artificially incubated eastern collared lizard eggs that had been laid in captivity in artificial nests had higher hatching success than those laid outside of the artificial nests. Two of five replicated studies (including one randomized, controlled study) in India, Spain and China found that hatching success of artificially incubated lizard eggs was lower at higher incubation temperatures. Two studies found that hatching success was similar across all incubation temperatures. The other study found that hatching success was not affected by temperature fluctuations during artificial incubation. Survival (2 studies): One replicated, randomized study in New Zealand found that survival of artificially incubated lizards was higher for individuals incubated at higher temperatures. One replicated, randomized study in Spain found that survival of artificially incubated common chameleon hatchlings was affected by incubation temperature but not moisture levels. Condition (7 studies): Three of five replicated studies (including three randomized studies) in Spain, New Zealand and China found that the size or morphology of artificially incubated lizard hatchlings was similar across all incubation temperatures or was not affected by temperature fluctuations. One study found that growth of artificially incubated common chameleon hatchlings was lower for individuals incubated at higher temperatures. The other study found that lizards from eggs incubated at higher temperatures had higher sprint speeds than those incubated at lower temperatures. One replicated, controlled study in Namibia reported that white-throated savanna monitors from artificially incubated eggs were similar in size to hatchlings from natural nests. One replicated, randomized study in India found that artificially incubating garden lizard eggs in cotton wool, soil or sand resulted in similar sized hatchlings. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3798https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3798Wed, 15 Dec 2021 18:33:49 +0000Collected Evidence: Collected Evidence: Relocate nests/eggs for artificial incubation: Crocodilians Six studies evaluated the effects of relocating nests/eggs for artificial incubation on crocodilian populations. Two studies were in the USA and one study was in each of Zimbabwe, Argentina, Venezuela and Australia. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (6 STUDIES) Reproductive success (5 studies): Two replicated studies in Zimbabwe and the USA reported that hatching success for 20,000 Nile crocodile eggs and >30,000 American alligator eggs that were artificially incubated was 74% and 61%. Two studies (including one replicated study) in Argentina and Venezuela reported that 43–100% of road-snouted caiman eggs, 66% of American crocodile eggs and 54% of Orinoco crocodile eggs hatched successfully following artificial incubation. One replicated, before-and-after study in Australia reported that hatching success of artificially incubated saltwater crocodile eggs differed when the project was under local compared to external management. Condition (1 study): One replicated, controlled, paired study in the USA found that American alligator eggs relocated for artificial incubation produced larger hatchlings than eggs left in situ. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3799https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3799Wed, 15 Dec 2021 19:14:49 +0000Collected Evidence: Collected Evidence: Relocate nests/eggs for artificial incubation: Tuatara Two studies evaluated the effects of relocating nests/eggs for artificial incubation on tuatara populations. Both studies were in New Zealand. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (2 STUDIES) Reproductive success (2 studies): One of two replicated studies (including one controlled study) in New Zealand reported that hatching success of tuatara eggs relocated for artificial incubation was 86–100%. The other study reported hatching success of 44%. Condition (1 study): One replicated, controlled study in New Zealand found that 10 months after hatching, artificially incubated tuatara were larger that those from natural nests. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3800https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3800Wed, 15 Dec 2021 19:27:29 +0000