Collected Evidence: Collected Evidence: Protect brownfield sites We have captured no evidence for the effects of interventions to protect brownfield sites from insensitive re-development. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested 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%2F3https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3Tue, 18 May 2010 14:57:41 +0100Collected Evidence: Collected Evidence: Protect existing natural or semi-natural habitat to prevent conversion to agriculture We have captured no evidence for the effects of protecting areas of natural or semi-natural habitat on bee populations or communities. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested 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%2F5https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F5Thu, 20 May 2010 19:58:47 +0100Collected Evidence: Collected Evidence: Protect in-field trees (includes management such as pollarding and surgery) We have captured no evidence for the effects of protecting in-field trees on farmland wildlife. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested 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%2F75https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F75Mon, 24 Oct 2011 21:07:09 +0100Collected Evidence: Collected Evidence: Protect individual nests of ground-nesting birds Two replicated, randomized, controlled studies from Sweden found providing nest exclosures offered some benefits to ground-nesting birds. One study found that protected nests had higher average daily survival rates than unprotected nests for both common redshank and northern lapwing, however, this study also reported higher predation of adult redshank on protected nests. One study found that the average hatching rate for southern dunlin was higher for protected rather than unprotected nests. This study also found no difference in the number of fledglings, breeding adults or new recruits during two periods with and without nest protection.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F108https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F108Mon, 24 Oct 2011 22:04:47 +0100Collected Evidence: Collected Evidence: Protect in-field trees We found no evidence for the effects of protecting in-field trees on bird populations. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested 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%2F184https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F184Sun, 10 Jun 2012 12:59:35 +0100Collected Evidence: Collected Evidence: Protect nest trees before burning We found no evidence for the effects of protecting nest trees of bird populations before burning. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested 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%2F325https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F325Thu, 26 Jul 2012 16:48:25 +0100Collected Evidence: Collected Evidence: Protect nest sites from competitors Two replicated studies from the USA found that red-cockaded woodpecker Picoides borealis populations increased in five forests after several interventions, including the installation of restrictor plates around nesting holes, were implemented. A study from Puerto Rico found evidence for lower competition between Puerto Rican parrots Amazona vittata and pearly-eyed thrashers Margarops fuscatus after modifications were made to nest boxes. A replicated, controlled study from the USA found weak evidence for the effects of exclusion devices on house sparrows Passer domesticus nesting in nest boxes and a study from the USA found that fitting restrictor plates to red-cockaded woodpecker holes reduced the number that were enlarged.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F426https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F426Fri, 17 Aug 2012 17:45:26 +0100Collected Evidence: Collected Evidence: Protect habitat along elevational gradients We found no evidence for the effects of protecting habitat along elevational gradients on amphibian populations. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested 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%2F810https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F810Thu, 22 Aug 2013 15:05:16 +0100Collected Evidence: Collected Evidence: Protect habitats for amphibians One replicated, site comparison study in the UK found that populations of natterjack toads were better protected at sites with a statutory level of habitat protection than those outside protected areas. One before-and-after study in the UK found that a common frog population increased but common toads decreased following the protection of a pond during development.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F820https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F820Fri, 23 Aug 2013 10:25:04 +0100Collected Evidence: Collected Evidence: Protect important food/nest trees before burning We found no evidence for the effects of protecting important food/nest trees before burning on primate populations. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested 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%2F1518https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1518Thu, 19 Oct 2017 09:23:12 +0100Collected Evidence: Collected Evidence: Protect greenfield sites or undeveloped land in urban areas We found no studies that evaluated the effects of protecting greenfield sites or undeveloped land in urban areas on bat 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%2F1934https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1934Fri, 30 Nov 2018 14:43:33 +0000Collected Evidence: Collected Evidence: Protect mammals close to development areas (e.g. by fencing) We found no studies that evaluated the effects of protecting mammals close to development areas (e.g. by fencing). 'We found no studies' means that we have not yet found any studies that have directly evaluated this intervention during our systematic journal and report searches. Therefore, we have no evidence to indicate whether or not the intervention has any desirable or harmful effects.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2324https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2324Wed, 20 May 2020 11:54:59 +0100Collected Evidence: Collected Evidence: Protect habitat along elevational gradients We found no studies that evaluated the effects on mammals of protecting habitat along elevational gradients. ‘We found no studies’ means that we have not yet found any studies that have directly evaluated this intervention during our systematic journal and report searches. Therefore, we have no evidence to indicate whether or not the intervention has any desirable or harmful effects.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2552https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2552Tue, 09 Jun 2020 10:36:21 +0100Collected Evidence: Collected Evidence: Protect greenfield sites or undeveloped land in urban areas We found no studies that evaluated the effects of protecting greenfield sites or undeveloped land in urban areas 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%2F3477https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3477Fri, 03 Dec 2021 11:37:24 +0000Collected Evidence: Collected Evidence: Protect habitat along elevational gradients We found no studies that evaluated the effects of protecting habitat along elevational gradients 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%2F3647https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3647Thu, 09 Dec 2021 15:47:19 +0000Collected Evidence: Collected Evidence: Protect habitat: All reptiles (excluding sea turtles) Seventeen studies evaluated the effects of protecting habitat on reptile populations (excluding sea turtles). Four studies were in the USA, two were in each of Australia and Brazil, and one was in each of Canada, Madagascar, South Africa, Spain, Hong Kong, Argentina, the borders of Zambia and Zimbabwe, Pakistan and Mexico. COMMUNITY RESPONSE (5 STUDIES) Richness/diversity (5 studies): Three of five studies (including two replicated, site comparison studies) in the USA, South Africa, Australia, Pakistan and Mexico found mixed effects of protected areas on reptile species richness and combined reptile and amphibian species richness. The other two studies found that protected areas had higher reptile species richness than unprotected farmland. POPULATION RESPONSE (16 STUDIES) Abundance (13 studies): Six of 11 studies (including five replicated, site comparison studies) in the USA, Canada, Hong Kong, Mexico, Australia, South Africa, Argentina, the border of Zambia and Zimbabwe and Pakistan found that protected areas had a higher abundance of reptiles, tortoises, Nile crocodiles and combined reptiles and amphibians than areas with less or no protection. Four studies found mixed effects of protection on the abundance of reptiles and big-headed turtles. The other study found that water bodies in protected areas had fewer eastern long-necked turtles than those in suburban areas. One site comparison study in Brazil found that areas with community-based management of fishing practices, which included protecting river turtle nesting beaches, had more river turtles than areas that did not manage fishing practices. One site comparison study in Madagascar found that the abundance of different sized radiated tortoises in a protected area was more similar to that of an exploited population than to an unexploited population. Occupancy/range (2 studies): One replicated, site comparison study in Argentina found that Argentine tortoises were found in one of two protected areas and two of three unprotected areas. One before-and-after study in Brazil found that most reptile species were still present 20 years after an area was protected. Survival (2 studies): One replicated, randomized, site comparison study in the USA found that in areas with greater protections, survival of Agassiz’s desert tortoises was higher than in areas with less protections. One replicated, site comparison study in Spain found that roads running through protected areas had more reptile road deaths than roads in unprotected areas. Condition (4 studies): Two of three site comparison studies (including one replicated study) in the USA, Australia and Hong Kong found that protected areas had larger red-eared sliders and big-headed turtles compared to areas where harvesting was allowed or was thought to be occurring illegally. The other study found that eastern long-necked turtles in protected areas grew slower and were smaller than turtles in suburban areas. One site comparison study in Madagascar found that radiated tortoises in a protected area had similar genetic diversity compared to populations outside of the protected area. BEHAVIOUR (1 STUDY) Use (1 study): One replicated study in the USA found that a protected area was used by common chuckwallas. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3661https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3661Fri, 10 Dec 2021 10:53:15 +0000Collected Evidence: Collected Evidence: Protect habitat: Sea turtles Four studies evaluated the effects of protecting habitat on sea turtle populations. One study was in each of Costa Rica, the Seychelles, Belize and the USA. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (4 STUDIES) Abundance (3 studies): One before-and-after study in Costa Rica found that after an area was protected, there were fewer nesting female leatherback turtles than before protection. One replicated, randomized, site comparison study off the coast of Belize found that in protected areas there were more hawksbill turtles than outside. One site comparison study in the USA found that differences in the abundance of green, loggerhead and hawksbill turtles in protected and unprotected areas were mixed. Reproductive success (2 studies): One before-and-after study in Costa Rica found that after an area was protected, more leatherback turtle hatchlings were produced than before protection. One before-and-after study in the Seychelles found that nesting activity by green turtles increased following both habitat and species protection. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3662https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3662Fri, 10 Dec 2021 10:56:12 +0000Collected Evidence: Collected Evidence: Protect nests and nesting sites from predation using artificial nest covers: Sea turtles Fifteen studies evaluated the effects of protecting nests and nesting sites from predation using artificial nest covers on sea turtle populations. Six studies were in the USA, two were in each of Turkey and Australia, and one was in each of Greece, Qatar, Indonesia, Cape Verde and Costa Rica. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (15 STUDIES) Reproductive success (15 studies): Eight of 14 studies (including 10 replicated, controlled studies) in the USA, Turkey, Qatar, Indonesia, Cape Verde, Australia and Costa Rica found that sea turtle, loggerhead, hawksbill and artificial sea turtle nests with artificial covers were predated less frequently than nests with no covers. Three studies found that covering sea turtle nests had mixed effects on predation, depending on predator species or year. One study found that loggerhead turtle nests with artificial covers were predated more frequently than nests with no covers. One study found that olive ridley turtle nests with and without artificial covers were all predated. The other study found that predation attempts of green and hawksbill turtle nests with artificial covers were similar compared to nests with no cover, but that predation success was affected by the cover design. Three studies also found that sea turtle and loggerhead turtle nests with artificial covers had higher hatching success than nests with no covers. One study also found that loggerhead turtle nests with artificial covers had similar hatching and emergence success compared to nests with no covers. One replicated, controlled study in Greece found that covering loggerhead turtle nests had mixed effects on hatching success compared to nests with no covers. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3686https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3686Fri, 10 Dec 2021 16:10:02 +0000Collected Evidence: Collected Evidence: Protect nests and nesting sites from predation using artificial nest covers: Tortoises, terrapins, side-necked & softshell turtles Seven studies evaluated the effects of protecting nests and nesting sites from predation using artificial nest covers on tortoise, terrapin, side-necked and softshell turtle populations. Five studies were in the USA and one was in each of the Galápagos and Canada. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (7 STUDIES) Reproductive success (7 studies): Two replicated studies (including one controlled study) in the Galápagos and the USA found that Galápagos giant tortoise nests surrounded by rock-walled corrals and bog turtle nests covered with cages were predated less frequently than unprotected nests. Two replicated studies (including one randomized, controlled study) in Canada and the USA found that nests of painted and snapping turtles and bog turtles covered with cages had similar hatching success compared to nests left uncovered. One of two replicated controlled studies (including one randomized study) in Canada and the USA found that painted and snapping turtle nests protected by three different cage types were predated a similar amount. The other study found mixed effects of different cage designs on predation rate of artificial nests at a diamondback terrapin nesting site. One replicated, before-and-after study in the USA found that diamondback terrapin nests covered by a nest box with an electrified wire were predated less frequently than nests under a box with no wire. One before-and-after study in the USA found that over half of eggs from bog turtle nests covered with cages in an area grazed by cattle hatched successfully. One replicated, controlled study in the USA found that diamondback terrapin nests covered with cages had hatching success of 55–93%, and 83–100% of uncaged nests were predated. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3687https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3687Fri, 10 Dec 2021 17:08:55 +0000Collected Evidence: Collected Evidence: Protect nests and nesting sites from predation using artificial nest covers: Snakes & lizards We found no studies that evaluated the effects of protecting nests and nesting sites from predation using artificial nest covers 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%2Fwww.conservationevidence.com%2Factions%2F3688https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3688Fri, 10 Dec 2021 17:26:23 +0000Collected Evidence: Collected Evidence: Protect nests and nesting sites from predation using artificial nest covers: Crocodilians We found no studies that evaluated the effects of protecting nests and nesting sites from predation using artificial nest covers 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%2Fwww.conservationevidence.com%2Factions%2F3689https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3689Fri, 10 Dec 2021 17:28:19 +0000Collected Evidence: Collected Evidence: Protect nests and nesting sites from predation by camouflaging nests Two studies evaluated the effects of protecting nests and nesting sites from predation by camouflaging nests on reptile populations. One study was in the USA and one was in Costa Rica. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (2 STUDIES) Reproductive success (2 studies): One replicated, controlled study in the USA found that Ouachita map turtle nests that were disguised by sweeping with a broom were predated at a similar rate as unswept nests. One before-and-after, site comparison study in Costa Rica found that camouflaged (details of method not provided) olive ridley turtle nests had similar hatching and emergence success compared to nests moved to a hatchery. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3691https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3691Fri, 10 Dec 2021 17:31:50 +0000Collected Evidence: Collected Evidence: Protect nests and nesting sites from predation by creating new nesting sites One study evaluated the effects of protecting nests and nesting sites from predation by creating new nesting sites on reptile populations. This study was in Spain. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Reproductive success (1 study): One replicated, controlled study in Spain found that predation rate of artificial Hermann’s tortoise nests in newly created nesting sites was similar to the predation rate in natural nesting sites. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3693https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3693Fri, 10 Dec 2021 17:39:17 +0000Collected Evidence: Collected Evidence: Protect greenfield sites or undeveloped land in urban areas Two studies evaluated the effects of protecting greenfield sites or undeveloped land in urban areas on butterflies and moths. One study was in Singapore and the other was in Mexico. COMMUNITY RESPONSE (2 STUDIES) Richness/diversity (2 studies): Two site comparison studies (including one replicated study) in Singapore and Mexico found that protected native forest and grassland in urban areas had a higher species richness of butterflies than urban parks or non-native Eucalyptus plantations. POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3836https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3836Mon, 04 Jul 2022 15:25:46 +0100Collected Evidence: Collected Evidence: Protect in-field trees One study evaluated the effects of protecting in-field trees on butterflies and moths. The study was in Sweden. COMMUNITY RESPONSE (1 STUDY) Richness/diversity (1 study): One replicated, site comparison study in Sweden found that where more trees and trees of more species had been retained in pastures, butterfly species richness was higher, but richness was lower when a high proportion of those trees were large. POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3978https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3978Thu, 18 Aug 2022 10:40:32 +0100
What Works 2021 cover

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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