Collected Evidence: Collected Evidence: Protect bird nests using electric fencing One before-and-after study from the UK found an increase in tern numbers after the erection of an electric fence, whilst a study from the USA found an increase in the number of nests. Five studies from the USA found higher survival or productivity at wader or seabird colonies with electric fencing, compared to areas without fencing, although one study found that hatching rates were no different, whilst nesting success was only higher in one of two years. One study from the USA found lower predation by mammalian predators inside electric fence exclosures, whilst predation by birds was higher. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F188https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F188Wed, 13 Jun 2012 16:59:40 +0100Collected Evidence: Collected Evidence: Promote sustainable alternative livelihoodsA single before-and-after study in Costa Rica found an increase in a scarlet macaw Ara macao population following several interventions including the promotion of sustainable, macaw-based livelihoods.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F273https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F273Thu, 19 Jul 2012 18:25:59 +0100Collected Evidence: Collected Evidence: Protect brownfield or ex-industrial sites We found no evidence for the effects of protecting brownfield sites 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%2F786https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F786Thu, 22 Aug 2013 14:26:33 +0100Collected Evidence: Collected Evidence: Protect brownfield or ex-industrial sites One study evaluated the effects of protecting brownfield or ex-industrial sites on bat populations. The study as in the USA. COMMUNITY RESPONSE (1 STUDY) Richness/diversity (1 study): One study in the USA found that five bat species were recorded within a protected urban wildlife refuge on an abandoned manufacturing site. POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (0 STUDIES)  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F953https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F953Fri, 20 Dec 2013 09:36:12 +0000Collected Evidence: Collected Evidence: Procambarus crayfish control: Trapping and removal One controlled, replicated study in Italy found that baiting traps with food (tinned meat) trapped the most red swamp crayfish compared to the use of male and female pheromones or the control (no bait). Over half of all crayfish caught were found in traps baited with food.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1029https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1029Fri, 03 Jul 2015 15:14:42 +0100Collected Evidence: Collected Evidence: Procambarus crayfish control: Trapping combined with encouragement of predators A before-and-after study in Switzerland found that introducing predators, combined with trapping significantly reduced red swamp crayfish populations in a pond. A second replicated, controlled study from Italy demonstrated that trapping and predation in combination was more effective at reducing red swamp crayfish populations than predation alone.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1031https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1031Fri, 03 Jul 2015 15:16:05 +0100Collected Evidence: Collected Evidence: Prohibit (livestock) farmers from entering protected areas One before-and-after, site comparison in Rwanda found that the number of young gorillas increased after cattle were removed from a protected area, alongside other interventions. A before-and-after study in Rwanda, Uganda, and the Democratic Republic of Congo found that a mountain gorilla population decreased over time following the removal of livestock from a number of protected areas, alongside other interventions. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1432https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1432Tue, 17 Oct 2017 09:58:38 +0100Collected Evidence: Collected Evidence: Promote careful bat-related eco-tourism to improve behaviour towards bats We found no studies that evaluated the effects of promoting careful bat-related eco-tourism to improve behaviour towards bats. ‘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%2F2042https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2042Wed, 05 Dec 2018 18:39:25 +0000Collected Evidence: Collected Evidence: Promote natural carbon sequestration species and/or habitats We found no studies that evaluated the effects of promoting natural carbon sequestration species and/or habitats 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%2F2221https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2221Tue, 22 Oct 2019 13:38:01 +0100Collected Evidence: Collected Evidence: Protect bats within roosts from disturbance or predation by native species We found no studies that evaluated the effects of protecting bat roosts from disturbance or predation by native species on bat 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%2F2287https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2287Wed, 20 Nov 2019 16:35:02 +0000Collected Evidence: Collected Evidence: Prohibit or restrict hunting of a species Five studies evaluated the effects of prohibiting or restricting hunting of a mammal species. One study each was in Norway, the USA, South Africa, Poland and Zimbabwe. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (5 STUDIES) Abundance (2 studies): Two studies (including one before-and-after study), in the USA and Poland, found that prohibiting hunting led to population increases of tule elk and wolves. Survival (3 studies): A before-and-after study in Norway found that restricting or prohibiting hunting did not alter the number of brown bears killed. A study in Zimbabwe reported that banning the hunting, possession and trade of Temminck’s ground pangolins did not eliminate hunting of the species. A before-and-after study in South Africa found that increasing legal protection of leopards, along with reducing human-leopard conflict by promoting improved animal husbandry, was associated with increased survival. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2597https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2597Thu, 11 Jun 2020 15:05:02 +0100Collected Evidence: Collected Evidence: Prohibit or restrict hunting of particular sex/ breeding status/age animals Two studies evaluated the effects of prohibiting or restricting hunting of particular sex, breeding status or age animals. Both studies were in the USA. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (2 STUDIES) Reproduction (2 studies): Two replicated, before-and-after studies, in the USA, found that limiting hunting of male deer did not increase the numbers of young deer/adult female. Population structure (1 study): A replicated, before-and-after study in the USA found that limiting hunting of older male elk resulted in an increased ratio of male:female elk. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2609https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2609Thu, 11 Jun 2020 16:29:44 +0100Collected Evidence: Collected Evidence: Promote sustainable alternative livelihoods We found no studies that evaluated the effects of promoting sustainable alternative livelihoods on mammals. ‘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%2F2623https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2623Fri, 12 Jun 2020 10:50:30 +0100Collected Evidence: Collected Evidence: Promote mammal-related ecotourism We found no studies that evaluated the effects on mammals of promoting mammal-related ecotourism. ‘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%2F2624https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2624Fri, 12 Jun 2020 10:52:50 +0100Collected Evidence: Collected Evidence: Prohibit or restrict hunting of marine and freshwater mammal species Five studies evaluated the effects of prohibiting hunting of marine mammal species. One study was in each of the Kattegat and Skagerrak seas (Denmark and Sweden), the North Atlantic Ocean, North Pacific Ocean and the Southern Hemisphere, the South Pacific Ocean (Australia), the North Atlantic Ocean (Greenland) and the Southern Ocean (Australia). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (5 STUDIES) Abundance (5 studies): Four of five studies (including three before-and-after studies) in the Kattegat and Skagerrak Seas, the South Pacific Ocean, the North Atlantic Ocean and the Southern Ocean found that after hunting was prohibited, the abundance of harbour seals and humpback whales increased over 7–30 years. The other study found that numbers of mature male sperm whales did not differ significantly before or 31 years after hunting was prohibited. One review in the North Atlantic Ocean, North Pacific Ocean and the Southern Hemisphere found significant increase rates for 10 of 12 baleen whale populations during 7–21 years after legislation to prohibit hunting was introduced. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2780https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2780Thu, 04 Feb 2021 16:09:52 +0000Collected Evidence: Collected Evidence: Promote knowledge exchange between fishers to improve good practice We found no studies that evaluated the effects of promoting knowledge exchange between fishers to improve good practice 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%2F2814https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2814Fri, 05 Feb 2021 10:10:50 +0000Collected Evidence: Collected Evidence: Promote fish and seafood certification (e.g. ecolabels) to reduce consumer demand for fisheries that threaten mammals We found no studies that evaluated the effects of promoting fish and seafood certification (e.g. ecolabels) to reduce consumer demand for fisheries that threaten mammals 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%2F2836https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2836Fri, 05 Feb 2021 16:09:36 +0000Collected Evidence: Collected Evidence: Produce guidance for marsh or swamp conservation One study evaluated the effects, on vegetation or human behaviour, of producing guidance for marsh or swamp conservation. The study was in Sri Lanka. VEGETATION COMMUNITY   VEGETATION ABUNDANCE   VEGETATION STRUCTURE   OTHER Survival (1 study): One study of coastal sites in Sri Lanka found that planted mangrove propagules/seedlings had a higher survival rate in sites where published guidance had been consulted to select appropriate areas for planting, than in sites where guidance was not consulted. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3392https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3392Mon, 12 Apr 2021 12:07:08 +0100Collected Evidence: Collected Evidence: Protect brownfield or ex-industrial sites in urban areas One study evaluated the effects of protecting brownfield or ex-industrial sites in urban areas. This study was in the UK. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (1 STUDY) Use (1 study): One study in the UK reported that an ex-industrial site that was protected was occupied by up to four species of reptiles. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3478https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3478Fri, 03 Dec 2021 11:43:50 +0000Collected Evidence: Collected Evidence: Promote knowledge exchange between fishers to improve good practice One study evaluated the effects on reptile populations of promoting knowledge exchange between fishers to improve good practice. This study was in the USA. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Survival (1 study): One before-and-after study in the USA found that following the introduction of a tool to help facilitate knowledge exchange and the avoidance of loggerhead turtles, loggerhead turtle bycatch was similar compared to the two years before the tool was introduced. BEHAVIOUR (0 STUDIES) OTHER (1 STUDY) Human behaviour change (1 study): One before-and-after study in the USA found that following the introduction of a tool to help facilitate avoidance of loggerhead turtles, fishers did not spend less time fishing in the areas recommended for avoidance by the tool.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3558https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3558Wed, 08 Dec 2021 14:13:04 +0000Collected Evidence: Collected Evidence: Prohibit certain gear types Two studies examined the effects of prohibiting certain gear types on marine fish populations. One study was in the Indian Ocean (Kenya) and one was in the Kattegat (Sweden/Denmark).   COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Abundance (1 study): One replicated, site comparison study in the Indian Ocean found that in an area where all but one gear type was prohibited there was a higher fish density compared to areas where just one gear type was prohibited and to unrestricted areas. BEHAVIOUR (0 STUDIES) OTHER (1 STUDY) Reduction of unwanted catch (1 study): One replicated, before-and-after study in the Kattegat found that a combination of areas in which non-selective gear types were prohibited and long-term fishery closures reduced unwanted catch of cod compared to before. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3810https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3810Thu, 26 May 2022 14:57:28 +0100Collected Evidence: Collected Evidence: Prohibit the catching and/or landing of specific fish species We found no studies that evaluated the effects of prohibiting catching and/or landing of specific 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%2F3822https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3822Fri, 27 May 2022 08:51:56 +0100Collected Evidence: Collected Evidence: Prohibit high grading in which only the most profitable individuals or species are landed One study examined the effects of prohibiting high grading in which only the most profitable individuals or species are landed on marine fish populations. The study was in the North Sea/North Atlantic Ocean (UK).   COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (0 STUDIES) OTHER (1 STUDY) Commercial catch abundance/landings (1 study): One replicated, before-and-after study in the North Sea/North Atlantic Ocean reported that a ban on high grading did not eliminate the discarding of legal-sized but unwanted common megrim Lepidorhombus whiffiagonis that were required to be landed. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3823https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3823Fri, 27 May 2022 08:55:44 +0100Collected Evidence: Collected Evidence: Protect and connect habitat along elevational gradients We found no studies that evaluated the effects on butterflies and moths of protecting and connecting habitat along elevational gradients. ‘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%2F3856https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3856Tue, 05 Jul 2022 15:27:59 +0100Collected Evidence: Collected Evidence: Produce coffee in shaded plantations Three studies evaluated the effects on butterflies and moths of producing coffee in shaded plantations. Two studies were in Mexico and one was in Puerto Rico. COMMUNITY RESPONSE (2 STUDIES) Richness/diversity (2 studies): One paired sites, site comparison study in Mexico found that a plantation with its original canopy but understory replaced with coffee had higher species richness of fruit-eating butterflies than one with its original canopy and understory replaced with coffee and other vegetation or those with canopies replaced with other shading trees and understories replaced with coffee with or without other vegetation. One site comparison study in Mexico found that shaded coffee plantations had a higher species richness of caterpillars than a sun-grown monoculture. POPULATION RESPONSE (2 STUDIES) Abundance (2 studies): Two site comparison studies (including one replicated study) in Puerto Rico and Mexico found that shade-grown coffee plantations had a greater abundance of caterpillars than sun-grown coffee plantations. One of these studies also found that the abundance of coffee leaf miner was similar in shade-grown and sun-grown plantations. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3931https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3931Thu, 11 Aug 2022 19:51:40 +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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