Collected 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: Limit the density of livestock on farmland near peatlands We found no studies that evaluated the effects, on peatland vegetation, of limiting the density of livestock on farmland near peatlands. ‘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%2F1786https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1786Tue, 28 Nov 2017 08:16:57 +0000Collected Evidence: Collected Evidence: Limit the amount of stabilisation material used We found no studies that evaluated the effects of limiting the amount of stabilisation material used 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 effectsCollected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2057https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2057Mon, 21 Oct 2019 13:38:24 +0100Collected Evidence: Collected Evidence: Limit the number and/or extent of, or prohibit additional, renewable energy installations in an area We found no studies that evaluated the effects of limiting the number and/or extent of, or prohibit additional, renewable energy installations in an area 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%2F2078https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2078Mon, 21 Oct 2019 14:46:10 +0100Collected Evidence: Collected Evidence: Limit the number of fishing days We found no studies that evaluated the effects of limiting the number of fishing days 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%2F2108https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2108Tue, 22 Oct 2019 09:35:36 +0100Collected Evidence: Collected Evidence: Limit the density of traps We found no studies that evaluated the effects of limiting the density of traps 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%2F2111https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2111Tue, 22 Oct 2019 09:38:18 +0100Collected Evidence: Collected Evidence: Limit the maximum weight and/or size of bobbins on the footrope We found no studies that evaluated the effects of limiting the maximum weight and/or size of bobbins on the footrope 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%2F2130https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2130Tue, 22 Oct 2019 10:26:05 +0100Collected Evidence: Collected Evidence: Limit the amount of storm wastewater overflow We found no studies that evaluated the effects of limiting the amount of storm wastewater overflow 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%2F2181https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2181Tue, 22 Oct 2019 12:40:17 +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: Limit the length of fishing gear in an area We found no studies that evaluated the effects of limiting the length of fishing gear in an area 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%2F2795https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2795Thu, 04 Feb 2021 16:37:57 +0000Collected Evidence: Collected Evidence: Limit size of trawl net openings We found no studies that evaluated the effects of limiting the size of trawl net openings 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%2F2804https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2804Thu, 04 Feb 2021 17:14:32 +0000Collected Evidence: Collected Evidence: Limit the amount of storm wastewater overflow We found no studies that evaluated the effects of limiting the amount of storm wastewater overflow 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%2F2868https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2868Mon, 08 Feb 2021 11:28:18 +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: Limit or exclude off-road vehicle use Two studies evaluated the effects of limiting or excluding off-road vehicle use on reptile populations. Both studies were in the USA. COMMUNITY RESPONSE (1 STUDIES) Richness/diversity (1 studies): One replicated, site comparison study found that restricting access of off-road vehicles and sheep had mixed effects on lizard species richness. POPULATION RESPONSE (2 STUDIES) Abundance (2 studies): One of two replicated, site comparison studies (including one randomized study) in the USA found that areas where off-road vehicles were completely excluded using fencing that also excluded livestock grazing had higher densities of Agassiz’s desert tortoises compared to areas with some restrictions or no restrictions. The other study found that restricting off-road vehicle and sheep access had mixed effects on lizard abundance. Survival (1 study): One replicated, randomized, site comparison study in the USA found that in areas where off-road vehicles were completely excluded, death rates of Agassiz’s desert tortoises were lower than in areas with some restrictions or no restrictions. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3502https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3502Mon, 06 Dec 2021 17:44:34 +0000Collected Evidence: Collected Evidence: Limit road construction in important habitats We found no studies that evaluated the effects of limiting road construction in important habitats 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%2F3506https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3506Tue, 07 Dec 2021 10:00:01 +0000Collected Evidence: Collected Evidence: Limit or prohibit specific fishing methods One study evaluated the effects of limiting or prohibiting specific fishing methods on reptile populations. This study was in Brazil. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Abundance (1 study): One site comparison study in Brazil found that in areas where a fishing agreement was implemented that involved limiting the use of gill nets along with a wider suit of measures had more river turtles than areas that did not implement the agreement. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3546https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3546Wed, 08 Dec 2021 09:26:10 +0000Collected Evidence: Collected Evidence: Limit the length of fishing gear or density of traps in an area We found no studies that evaluated the effects on reptile populations of limiting the length of fishing gear or density of traps in an area. ‘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%2F3551https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3551Wed, 08 Dec 2021 12:11:09 +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 the number of fishing days One study examined the effects of limiting the number of fishing days on marine fish populations. The study was in the Mediterranean Sea (Italy). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Abundance (1 study): One before-and-after study in the Mediterranean Sea reported that in the 10 years following a decrease in overall number of days fished by a bottom trawl fleet, there was a higher biomass of thornback and brown rays. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3804https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3804Thu, 26 May 2022 14:24:22 +0100Collected 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 +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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