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: Legally protect habitats Four studies (two replicated) from Europe found population increases following habitat protection, more positive population trends in protected habitats, compared with outside, or with increases amounts of protected habitats. A literature review reported that a large number of cranes (Gruidae) of seven species used nature reserves in China, whilst a replicated, randomised and controlled study from Argentina found that some guilds of birds were found at higher species richnesses in protected forests, some at higher densities, and that some showed no differences. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F158https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F158Tue, 15 May 2012 13:48:22 +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: Legally protect primate habitat A review on the status of rhesus monkeys and grey snub-monkeys in China found that primate numbers increased or no more individuals were killed after the area was legally protected, alongside other interventions. One before-and-after study in Kenya found that Tana River red colobus monkey and crested mangabey numbers decreased despite the area being declared legally protected, alongside other interventions. One before-and-after study in China found that Hainan gibbon numbers increased by 34% over nine years after the area was declared legally protected. One before-and-after study in Brazil found that most golden lion tamarins did not survive over seven years despite being reintroduced to a legally protected area, alongside other interventions yet they reproduced and surviving offspring partly compensated adult mortality. Two before-and-after studies in the Republic of Congo and Gabon found that most central chimpanzees and lowland gorillas reintroduced to areas that received legal protection, alongside other interventions, survived over 4–5 years. One controlled, site comparison study in Mexico found that black howler monkeys in protected areas had lower stress levels than individuals living in unprotected forest fragments. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1578https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1578Fri, 20 Oct 2017 12:49:30 +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 peatlands Five studies evaluated the effects on peatland habitats of legally protecting them: two of tropical peat swamp forest, two of unspecified peatlands and one of a bog. Peatland habitat (3 studies): Two studies in Indonesia reported that peat swamp forest was lost from within the boundaries of national parks. However, one of these studies was a site comparison and reported that forest loss was greater outside the national park. One before-and-after study of peatlands in China reported that peatland area initially decreased, but then increased, following legal protection. Plant community composition (1 study): One before-and-after study in a bog in Denmark reported that the plant community compositon changed over 161 years of protection. In particular, woody plants became more abundant. Vegetation cover (1 study): One site comparison study in a peatland in Chile found that a protected area had greater vegetation cover (total, herbs and shrubs) than an adjacent grazed and moss-harvested area. Overall plant richness/diversity (2 studies): One before-and-after study in Denmark reported that the number of plant species in a protected bog fluctuated over time, with no clear trend. One site comparison study in a peatland in Chile found that a protected area had lower plant richness and diversity (but also fewer non-native species) than an adjacent grazed and harvested area. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1796https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1796Tue, 28 Nov 2017 08:26:41 +0000Collected 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: Legally protect bat habitats Five studies evaluated the effects of legally protecting bat habitats on bat populations. Four studies were in Europe and one was in India. COMMUNITY RESPONSE (2 STUDIES) Community composition (1 study): One replicated, site comparison study in India found that the composition of bat species was similar in protected forest and unprotected forest fragments. Richness/diversity (2 studies): Two replicated, site comparison or paired sites studies in Europe and India found that the number of bat species did not differ between protected and unprotected forests or forest fragments. One replicated, site comparison study in France found that protected sites had a greater number of bat species than unprotected sites. POPULATION RESPONSE (4 STUDIES) Abundance (4 studies): One replicated, site comparison study in the UK found that the activity (relative abundance) of Daubenton’s bats was higher over rivers on farms in protected areas than in unprotected areas. One replicated, paired sites study in Europe found that the activity of common noctule bats was higher in protected forests than unprotected forests, but bat activity overall did not differ. Two replicated, site comparison studies in France and India found higher overall bat activity, higher activity of three of six bat species/species groups and a greater number of bats in protected sites and forests than unprotected sites and forests. BEHAVIOUR (1 STUDY)         Use (1 study): One study in Spain found that the distributions of 10 of 11 bat species overlapped with areas designated to protect them significantly more than by chance. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2045https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2045Thu, 06 Dec 2018 15:34:12 +0000Collected Evidence: Collected Evidence: Legally protect habitat for mammals Seven studies evaluated the effects of legally protecting habitat for mammals. One study each was in Zambia, the USA, Tanzania, Brazil, Nepal and India and one was a systematic review of sites with a wide geographic spread. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (7 STUDIES) Abundance (7 studies): A systematic review of protected areas across the globe found that 24 of 31 studies reported an increase in mammal populations in protected areas relative to unprotected areas. Three studies (including two site comparison studies), in Zambia, the USA and Nepal, found that populations of red lechwe, black bears and one-horned rhinoceros grew following site protection or were higher than in adjacent non-protected sites. One of three site comparison studies, in Tanzania, Brazil and India, found that populations of more mammal species increased inside protected areas than in adjacent unprotected areas. One study found that populations of only three of 11 species were higher on protected than on unprotected land whilst the third study found that 13 of 16 species were less abundant in a protected area than in a nearby unprotected area. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2559https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2559Tue, 09 Jun 2020 11:56:39 +0100Collected Evidence: Collected Evidence: Legislate to oblige fishers to retain and land all catch of species managed by quotas We found no studies that evaluated the effects of legislating to oblige fishers to retain and land all catch of quota species on marine fish 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%2F2694https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2694Wed, 02 Dec 2020 16:24:14 +0000Collected Evidence: Collected Evidence: License fish buyers We found no studies that evaluated the effects of licensing fish buyers on marine fish 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%2F2773https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2773Wed, 03 Feb 2021 11:25:34 +0000Collected 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: 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: Limit heavy vehicle use We found no studies that evaluated the effects of limiting heavy vehicle use 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%2F3493https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3493Mon, 06 Dec 2021 11:43:39 +0000Collected Evidence: Collected Evidence: Legally protect reptile species Six studies evaluated the effects of legally protecting reptile species on their populations. Two studies were in the Netherlands and one was in each of the USA, Australia, the Seychelles and Cape Verde. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (3 STUDIES) Abundance (2 studies): One of two studies (including one replicated, site comparison study and one before-and-after study) in the USA and Australia found that waterbodies where turtle harvesting was prohibited had a similar abundance of red-eared sliders and Texas spiny softshell turtles compared to unprotected waterbodies. The other study found that following legal protection and harvest regulation, the density of saltwater crocodile populations increased. Reproductive success (1 studies): One before-and-after study in the Seychelles found that following legal protection of both green turtles and their habitat, nesting activity increased. Condition (2 studies): Two studies (including one replicated, site comparison study and one before-and-after study) in the USA and Australia found that in areas with legal protection and/or harvest regulation, Texas spiny softshell turtles and saltwater crocodiles were larger than in areas with no protection or before protection began. One study also found that female red-eared sliders were larger, but males were a similar size in protected compared to unprotected waterbodies. BEHAVIOUR (0 STUDIES) OTHER (3 studies) Human behaviour change (3 studies): Two reviews in the Netherlands found that despite legislation protecting reptiles and their habitat, only one of four development projects completed their habitat compensation requirements or that compensatory slow worm habitat was not completed in time. Both studies also found that monitoring data was not available or that the success of a slow worm mitigation translocation could not be assessed. One replicated, before-and-after study in Cape Verde reported that following legal protections combined with public awareness campaigns, self-reported harvesting, selling and purchasing of sea turtles and turtle products decreased. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3705https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3705Mon, 13 Dec 2021 10:32:56 +0000Collected Evidence: Collected Evidence: Limit beam trawl width We found no studies that evaluated the effects of limiting beam trawl width on marine fish 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%2F3805https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3805Thu, 26 May 2022 14:36:31 +0100Collected Evidence: Collected Evidence: Limit dredge width or number of dredges per vessel We found no studies that evaluated the effects of limiting dredge width or number of dredges per vessel on marine fish 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%2F3806https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3806Thu, 26 May 2022 14:40:55 +0100Collected Evidence: Collected Evidence: Limit fishing activity by vessel size and/or engine power One study examined the effects of limiting fishing activity by vessel size and/or engine power on marine fish populations. The study was in the North Sea (Northern Europe).   COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Abundance (1 study): One before-and-after study in the North Sea found that after vessels with a higher engine power were excluded from an area for half of each year there was a higher abundance of commercially targeted fish, but no difference in the overall abundance of non-commercially targeted fish over five years. In addition, for all fish, abundance was higher for two of eight size-groups. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3809https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3809Thu, 26 May 2022 14:53:03 +0100Collected Evidence: Collected Evidence: Legally protect habitat Ten studies evaluated the effects on butterflies and moths of legally protecting habitat. Six studies were in the UK and one was in each of Australia, Singapore and Ireland and the USA. Three of the studies used data from the same national monitoring scheme across different years. COMMUNITY RESPONSE (3 STUDIES) Richness/diversity (3 studies): One replicated, site comparison study in Singapore found that protected primary or secondary forest reserves had a higher species richness of butterflies than unprotected forest fragments. One replicated, paired, site comparison study in Ireland reported that raised bogs protected as Special Areas of Conservation (where restoration had sometimes taken place) had a similar species richness of moths to unprotected bogs. One replicated, site comparison study in the UK found that, in the first three years after protection as Sites of Special Scientific Interest (SSSI), woodland, grassland and heathland sites lost a similar proportion of 29 threatened butterfly species to unprotected sites. POPULATION RESPONSE (8 STUDIES) Abundance (7 studies): Three of five site comparison studies (including four replicated studies and one before-and-after study) in the UK and Ireland found that sites protected as National Nature Reserves or Sites of Special Scientific Interest (SSSI) (in one case also managed by coppicing), or surrounded by SSSIs, had a higher abundance of heath fritillary, all butterflies and 30/57 species of butterfly than unprotected sites. However, one of these studies only found the result using one of two sets of sites. The other two studies found that grasslands protected as National Nature Reserves or SSSIs and raised bogs protected as Special Areas of Conservation had a similar total abundance of moths, and change in abundance of chalkhill blue butterflies, to unprotected sites. However, one of these studies found mixed results for individual moth species. One replicated, site comparison study in the USA found that, at sites with the highest levels of protection, abundances of Karner blue, frosted elfin and Persius duskywing did not change over time, whereas they decreased at sites with lower levels of protection. One replicated, site comparison study in the UK found that protected grasslands assessed as being in “Favourable” habitat condition had worse population trends for 4/8 butterfly species but better for 1/8 species than grasslands in “Unfavourable” condition. One study in Australia reported that after a grassland was designated as a local reserve, populations of golden sun-moth and pale sun-moth persisted for at least four years. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3831https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3831Mon, 04 Jul 2022 13:36:18 +0100Collected 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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