Collected Evidence: Collected Evidence: Legally protect large native treesA study in degraded savannah in Minas Gerais, Brazil showed that the stingless bee species Melipona quadrifasciata selectively nested in the protected cerrado tree Caryocar brasiliense, evidence that protecting this species from logging or wood harvesting has helped to conserve stingless bees.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F34https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F34Thu, 20 May 2010 09:28:04 +0100Collected Evidence: Collected Evidence: Enforce legislation to protect birds against persecution Two before-and-after studies have evaluated effects of legislative protection on bird species in Europe. Both found that legislation protects bird populations. One found increased population levels of raptors in Scotland, following protective legislation. One found increased survival of kestrels in Denmark stricter protection, but not necessarily population-level responses. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F101https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F101Mon, 24 Oct 2011 21:55:47 +0100Collected Evidence: Collected Evidence: Maintain traditional water meadows A replicated study from the UK found that northern lapwing and common redshank populations increased on nature reserves managed to maintain water meadows. Two replicated studies from the Netherlands found that there were more waders or birds overall on specially managed meadows or 12.5 ha plots including several management interventions than on conventional fields, but one study found that these differences were present before the management scheme was introduced and the other found no differences between individual fields under different management. A replicated study from the UK found that common snipe decreased on nature reserves managed to maintain water meadows and a replicated before-and-after study from the Netherlands found that wader population trends on specially managed meadows were no different to those on conventionally-managed meadows. A replicated study from the UK found that lapwing populations on three of four water meadow sites managed for conservation did not have high enough productivity to maintain population levels. All three sites were judged deficient in at least one management category.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F229https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F229Tue, 17 Jul 2012 15:37:55 +0100Collected Evidence: Collected Evidence: Legal protection of species Three reviews (including one systematic review) in the Netherlands and UK (Bosman et al. 2011, Spitzen-van der Sluijs et al. 2011, Lewis 2012) found that legal protection of amphibian species was not effective at protecting populations during development. Two reviews in the UK (Edgar et al. 2005, Lewis 2012) found that the number of great crested newt mitigation licences issued over 10 years increased to over 600 in England and Wales.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F779https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F779Thu, 22 Aug 2013 11:46:02 +0100Collected Evidence: Collected Evidence: Provide legal protection of forests from development We found no evidence for the effects of providing legal protection of forests from 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%2F1169https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1169Thu, 19 May 2016 09:37:01 +0100Collected Evidence: Collected Evidence: Legal protection of forests Two site comparison studies in Nigeria and Iran found that legal protection of forest increased tree species richness and diversity and the density of young trees. One replicated, paired site study in Mexico found no effect of forest protection on seed density and diversity of trees and shrubs.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1233https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1233Mon, 23 May 2016 11:25:48 +0100Collected Evidence: Collected Evidence: Implement legal protection for primate species under threat A before-and-after study in India found that following a ban on export of the species, a population of rhesus macaques increased over 17 years. Two studies in Thailand and India found that primate populations declined despite the respective species being legally protected, alongside other interventions. One before-and-after study in Malaysia found that the majority of introduced Müller's Bornean gibbons died despite legal protection, along with other interventions. A site comparison of five sites in Cameroon found that drill populations declined in four sites but increased at one, despite legal protection. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1524https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1524Thu, 19 Oct 2017 09:39:16 +0100Collected Evidence: Collected Evidence: Legally protect plant species affected by gathering We found no studies that evaluated the effects of legally protecting the species affected by gathering on shrublands. '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%2F1612https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1612Sun, 22 Oct 2017 10:27:26 +0100Collected Evidence: Collected Evidence: Legally protect shrubland We found no studies that evaluated the effects of legally protecting shrubland habitat on shrublands. '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%2F1674https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1674Sun, 22 Oct 2017 15:21:21 +0100Collected Evidence: Collected Evidence: Legally protect habitat around shrubland We found no studies that evaluated the effects of legally protecting shrubland habitat around shrubland on shrublands. '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%2F1675https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1675Sun, 22 Oct 2017 15:22:45 +0100Collected Evidence: Collected Evidence: Legally protect bats during development Four studies evaluated the effects of legally protecting bats by issuing licences during development on bat populations. The four studies were in the UK. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (2 STUDIES) Change in human behaviour (2 studies): One review in the UK found that the number of development licences for bats more than doubled over three years in Scotland. One review in the UK found that 81% of licensees did not carry out post-development monitoring to assess whether bats used the roost structures installed. OTHER (3 STUDIES) Impact on bat roost sites (3 studies): One review in the UK found that licenced activities during building developments had a negative impact on bat roosts, with 68% of roosts being destroyed. One replicated, before-and-after study in the UK found that five of 28 compensation roosts provided under licence were used, and two by similar or greater numbers of bats after development. One review in the UK found that 31–67% of compensation roosts provided under licence were used by bats. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1935https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1935Fri, 30 Nov 2018 14:50:33 +0000Collected Evidence: Collected Evidence: Legally protect bat species We found no studies that evaluated the effects of legally protecting bat species 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%2F2037https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2037Wed, 05 Dec 2018 18:29:39 +0000Collected Evidence: Collected Evidence: Create a Marine Protected Area or set levels of legal protection where natural climate refugia occur to further promote the persistence and recovery of species facing climate change We found no studies that evaluated the effects of creating a marine protected area or setting levels of legal protection where natural climate refugia occur to further promote the persistence and recovery of species facing climate change on subtidal benthic invertebrate populations.   ‘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%2F2222https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2222Tue, 22 Oct 2019 13:39:06 +0100Collected Evidence: Collected Evidence: Encourage community-based participation in land management Two studies evaluated the effects of encouraging community-based participation in management of mammals to reduce mammal persecution. One study was in Pakistan and one was in India. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Abundance (1 study): A study in Pakistan found that involving local communities with park management was associated with an increasing population of Himalayan brown bears. BEHAVIOUR (0 STUDIES) OTHER (1 STUDY) Human behaviour change (1 study): A study in Namibia found that fewer farmers who engaged in community-based management of land, through membership of a conservancy, removed large carnivores from their land than did non-conservancy members. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2395https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2395Thu, 28 May 2020 10:25:29 +0100Collected Evidence: Collected Evidence: Legally protect areas where climate change impacts are predicted to be less severe We found no studies that evaluated the effects of legally protecting areas where climate change impacts are predicted to be less severe on marine and freshwater mammal 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%2F2912https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2912Mon, 08 Feb 2021 16:22:44 +0000Collected Evidence: Collected Evidence: Establish a network of legally protected areas We found no studies that evaluated the effects of establishing a network of legally protected areas on marine and freshwater mammal 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%2F2913https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2913Mon, 08 Feb 2021 16:23:32 +0000Collected Evidence: Collected Evidence: Legally protect habitat for marine and freshwater mammals Four studies evaluated the effects of legally protecting habitat for marine and freshwater mammals. One study was in each of the North Atlantic Ocean (Portugal), the South Pacific Ocean (New Zealand), the North Sea (UK) and the Port River estuary (Australia). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (4 STUDIES) Abundance (2 studies): One before-and-after study in the North Atlantic Ocean found that a population of Mediterranean monk seals increased during eight years after the islands they inhabited were legally protected. One before-and-after study in the North Sea found that a population of bottlenose dolphins was estimated to be a similar size before and after part of its range was protected. Survival (2 studies): One before-and-after study in the South Pacific Ocean found that the survival rate of Hector’s dolphins was higher after a coastal area was legally protected than before. One before-and-after study in the Port River estuary found that after the area became legally protected a similar number of Indo-Pacific bottlenose dolphin strandings were recorded compared to before protection, but the number of strandings caused by humans decreased. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2915https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2915Mon, 08 Feb 2021 16:29:11 +0000Collected Evidence: Collected Evidence: Legally protect marine and freshwater mammal species We found no studies that evaluated the effects of legally protecting marine and freshwater mammal species. ‘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%2F2923https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2923Mon, 08 Feb 2021 16:38:46 +0000Collected Evidence: Collected Evidence: Raise water level to restore degraded brackish/salt marshes Two studies evaluated the effects, on vegetation, of raising the water level to restore degraded brackish/salt marshes. One study was in the Netherlands and one was in Tunisia. VEGETATION COMMUNITY Community types (2 study): One before-and-after study of a lakeshore brackish/salt marsh in Tunisia reported an increase in coverage of bulrush-dominated vegetation relative to salt marsh vegetation over three years after modifying a canal to retain water in the marsh. One study of a salt marsh in the Netherlands reported increased coverage of pioneer succulent plant communities, and reduced coverage of short-grass communities, over approximately 10 years following abandonment of the drainage system (along with other interventions). Overall richness/diversity (1 study): One study of a salt marsh in the Netherlands reported that overall plant species richness increased over 14 years after abandoning drainage systems (along with other interventions). VEGETATION ABUNDANCE Individual species abundance (1 study): One study of a salt marsh in the Netherlands reported that some individual plant species became more common over 14 years after abandoning drainage systems (along with other interventions). These included saltbush Atriplex prostrata and seablite Suaeda maritima. Some other species became less common, including creeping bentgrass Agrostis stolonifera and common cordgrass Spartina anglica. VEGETATION STRUCTURECollected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3027https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3027Wed, 31 Mar 2021 14:47:25 +0100Collected Evidence: Collected Evidence: Designate protected area Four studies evaluated the overall effects, on vegetation or human behaviour, of designating protected areas involving marshes or swamps. There were two studies in China, one in Malaysia and one in Puerto Rico. VEGETATION COMMUNITY Overall extent (4 studies): Two studies (one replicated, one before-and-after) in China reported that the area of marsh, swamp or unspecified wetland in protected areas declined over 6–12 years. One replicated, site comparison study in Puerto Rico reported that protection had no clear effect on mangrove forest area, with similar changes over 25 years in protected and unprotected sites. One study of a mangrove forest in Malaysia reported that it retained at least 97% of its forest area over 98 years of protection as a forest reserve. VEGETATION ABUNDANCE   VEGETATION STRUCTURE Overall structure (2 studies): One replicated study in China reported “degradation” of the landscape structure of protected wetlands over 12 years. One before-and-after study in China reported fragmentation of wetland habitat within a protected area, but that this meant its structure became more like it had been 10–40 years previously. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3384https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3384Mon, 12 Apr 2021 08:40:54 +0100Collected Evidence: Collected Evidence: Provide general protection for marshes or swamps Three studies evaluated the overall effects, on vegetation or human behaviour, of providing general protection for marshes or swamps. There was one study in each of Puerto Rico, China and Canada. VEGETATION COMMUNITY Overall extent (3 studies): Two studies in China and Canada reported that the area of wetlands (including habitats other than marshes or swamps) in their study regions declined over 10–29 years, despite general protection of wetlands. However, in China, the decline was slower than in a previous period without protection. One before-and-after study of mangrove forests in Puerto Rico reported that their area increased following legal protection. VEGETATION ABUNDANCE   VEGETATION STRUCTURE Overall structure (1 study): One before-and-after study in China reported degradation in wetland landscape structure over 29 years when wetlands were generally protected. However, the decline was slower than in a previous period when wetlands were not protected. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3385https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3385Mon, 12 Apr 2021 09:30:20 +0100Collected Evidence: Collected Evidence: Regulate wildlife harvesting Four studies evaluated the effects of regulating wildlife harvesting on reptile populations. One study was in each of Costa Rica, Australia, Indonesia and Japan. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (2 STUDIES) Abundance (2 studies): One before-and-after study in Australia found that following legal protection and harvest regulations, the density of saltwater crocodile populations increased. One before-and-after study in Japan found that following regulation of the green turtle harvest in combination with allowing harvested turtles to lay eggs prior to being killed, the number of nesting females tended to be higher. Reproductive success (1 study): One before-and-after study in Japan found that following regulation of the green turtle harvest in combination with allowing harvested turtles to lay eggs prior to being killed, the number of hatchlings produced in natural nests tended to be higher. Condition (1 study): One before-and-after study in Australia found that following legal protection and harvest regulations, the average size of crocodiles increased. BEHAVIOUR (0 STUDIES) OTHER (2 STUDIES) Human behaviour change (2 studies): One replicated study in Costa Rica found that in an area with a legalized turtle egg harvest run by a community cooperative, a majority of people reported a willingness to do more to protect sea turtles. One study in Indonesia reported that quotas to regulate wildlife harvesting did not limit the number of individuals of three reptile species that were harvested and exported. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3538https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3538Tue, 07 Dec 2021 16:33:38 +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: Legally protect butterflies and moths We found no studies that evaluated the effects of legally protecting butterflies and moths. ‘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%2F3863https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3863Fri, 08 Jul 2022 11:54:50 +0100Collected Evidence: Collected Evidence: Legally protect large native trees We found no studies that evaluated the effects on butterflies and moths of legally protecting large native trees. ‘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%2F3865https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3865Fri, 08 Jul 2022 11:58:26 +0100
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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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