Conservation Evidence: Evidence Data

Collected Evidence: Collected Evidence: Remove or control predators using lethal controls: Sea turtles Four studies evaluated the effects of removing or controlling predators using lethal controls on sea turtle populations. All four studies were in the USA. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (4 STUDIES) Reproductive success (4 studies): Two before-and-after studies (including one controlled study) in the USA found that on islands where raccoons and feral pigs or only feral pigs were eradicated, fewer loggerhead and loggerhead and green turtle nests were predated than before predator control began. One replicated, randomized, controlled study in the USA found that controlling raccoons on short sections of a beach resulted in similar predation of loggerhead turtle nests compared to in sections of the beach with no control. One before-and-after study in the USA found that disruptions to a programme controlling raccoons and armadillos resulted in more predation of loggerhead, leatherback and green turtle nests. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3671https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3671Fri, 10 Dec 2021 11:54:30 +0000Collected Evidence: Collected Evidence: Remove or control predators using lethal controls: Tortoises, terrapins, side-necked & softshell turtles Seven studies evaluated the effects of removing or controlling predators using lethal controls on tortoise, terrapin, side-necked and softshell turtle populations. Four studies were in the USA and three were in Australia. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (7 STUDIES) Reproductive success (7 studies): Six of seven studies (including four replicated, controlled studies) in Australia and the USA found that in areas with mammal or fire ant control, and in two cases with fencing, fewer tortoise, turtle and terrapin nests were predated compared to areas with no control, or before control began. Two studies also found that predation increased again a year after control or in the second year of control. The other study found that following short-term fox control, a similar number of artificial eastern long-necked turtle nests were predated by foxes compared to before control began. Survival (3 studies): Two of three replicated, controlled studies (including one before-and-after study and one randomized study) in Australia and the USA found that in a fenced area with mammal or fire ant control, more gopher tortoise hatchlings survived for one year or at least 150 days compared to fenced areas with no control. The other study found mixed effects of fox control on survival of Murray short-necked turtles and broad-shelled turtles depending on turtle species, age and sex. BEHAVIOUR (1 STUDY) Behaviour change (1 study): One replicated, controlled, before-and-after study in Australia found that in areas with fox control, freshwater turtles nested further from the water and nests were more spread out compared to areas with no control, or before control began. Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3672https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3672Fri, 10 Dec 2021 12:10:34 +0000Collected Evidence: Collected Evidence: Remove or control predators using lethal controls: Snakes & lizards Twelve studies evaluated the effects of removing or controlling predators using lethal controls on snake and lizard populations. Four studies were in New Zealand, two were in each of Australia and the Galápagos, and one was in each of Indonesia, Antigua, Mexico and the Bahamas. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (12 STUDIES) Abundance (8 studies): Four of six before-and-after studies (including one replicated, controlled study) in New Zealand, Antigua, Mexico and the Bahamas found that on islands where both Pacific rats and European rabbits, Pacific rats, black rats and cats were eradicated, the abundance of lizards and Antiguan racer snakes. One study found that on an island where black rats were eradicated the number of San Salvador rock iguanas remained similar compared to before eradication. The other study found that eradicating mice had mixed effects on the abundance of lizards. One study also found that lizard abundance on an island with eradication was initially lower than on a predator free island, but after two years was similar or higher. One controlled, before-and-after study in Australia found that across areas with fox and cat control or only fox control, gecko and skink numbers were similar to an area with no control, but dragon lizard numbers were lower. One replicated, site comparison study in Australia found that in areas with fox control sand goanna abundance was higher and there was mixed effects on small lizard abundance compared to in areas with no control. Reproductive success (1 study): One before-and-after study in the Galápagos found that on an island where cats were eradicated the number of offspring of reintroduced Galápagos land iguanas was higher than before cat control began. Survival: (2 studies): One study in New Zealand found that survival of captive-bred Otago skinks released into an enclosure after mouse eradication was higher compared to when skinks were released in the presence of mice. One study in Indonesia reported no mortality of monitor lizards following use of poison baits to control black rats. Condition (2 studies): One of two studies in Indonesia and the Galápagos found that on an island where black rats were controlled, rodenticide was detected in the livers of lava lizards for up to 850 days after its use began. The other study reported no illness in monitor lizards following use of poison baits to control black rats. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3673https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3673Fri, 10 Dec 2021 12:27:59 +0000Collected Evidence: Collected Evidence: Remove or control predators using lethal controls: Crocodilians We found no studies that evaluated the effects of removing or controlling predators using lethal controls 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%2F3674https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3674Fri, 10 Dec 2021 13:42:04 +0000Collected Evidence: Collected Evidence: Remove or control predators using lethal controls: Tuatara One study evaluated the effects of removing or controlling predators using lethal controls on tuatara populations. This study was in New Zealand. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Abundance (1 study): One replicated, controlled, before-and-after study in New Zealand found that after eradicating Pacific rats the abundance of tuatara was higher on islands where rats were eradicated than on islands where some rats remained, and that the percentage of total tuatara that were juveniles increased. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3675https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3675Fri, 10 Dec 2021 13:44:19 +0000