Collected Evidence: Collected Evidence: Maintain species-rich, semi-natural grassland A before-and-after study from the UK found five species of conservation concern increased after the implementation of management designed to maintain unimproved grasslands. A replicated study from Switzerland found that wetland birds appeared to preferentially choose managed hay meadows; birds of open farmland avoided it.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F218https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F218Tue, 17 Jul 2012 12:27:00 +0100Collected Evidence: Collected Evidence: Replace nesting substrate following severe weatherTwo before-and-after studies from Canada found that common tern Sterna hirundo populations increased at one colony where nesting substrates were replaced, but decreased at a second. Several other interventions were used at both sites, making it difficult to evaluate the effects of substrate replacement.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F474https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F474Thu, 30 Aug 2012 12:47:05 +0100Collected Evidence: Collected Evidence: Create beetle banksNatural enemies in fields: Six studies from Canada, the UK and USA (three replicated, controlled, of which two were also randomised) examined the effects on predator numbers in adjacent crops. A review found that predators increased in adjacent crops, but one study found effects varied with time and another found no effect. Two studies found small or slow movements of predators from banks to crops. One study found greater beetle activity in fields but this did not improve pest predation. Natural enemies on banks: Four studies and a review found more invertebrate predators on beetle banks than in surrounding crops, but one of these found that effects varied with time. Eight studies from the UK and USA (including two randomised, replicated, controlled trials and two reviews) compared numbers of predatory invertebrates on beetle banks with other refuge habitats. Two studies found more natural enemies on beetle banks, but one of these found only seasonal effects. One review found similar or higher numbers of predators on beetle banks and four studies found similar or lower numbers. Pests: A replicated, randomised study and a review found the largest pest reductions in areas closest to a beetle bank or on the beetle bank itself. One review found fewer pests in fields with than without a beetle bank. Economics: One replicated, randomised, controlled trial and a review showed that beetle banks could make economic savings if they prevented pests from reaching a spray threshold or causing 5% yield loss. Beetle bank design: Two studies from the UK found certain grass species held higher numbers of predatory invertebrates than others. Crops studied were barley, field bean, maize, oats, pea, radish, rapeseed, soybean, wheat and pasture.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F729https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F729Thu, 30 May 2013 14:45:59 +0100Collected Evidence: Collected Evidence: Apply herbicides after restoration planting One replicated, randomized, controlled study in the USA found that controlling vegetation using herbicides after restoration planting decreased plant species richness and diversity.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1241https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1241Fri, 03 Jun 2016 09:52:52 +0100Collected Evidence: Collected Evidence: Water plants to preserve dry tropical forest species One replicated, controlled study in Hawaii found that watering plants increased the abundance and biomass of forest plants.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1242https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1242Fri, 03 Jun 2016 09:55:53 +0100Collected Evidence: Collected Evidence: Use 'set-asides' for primate protection within logging area We found no evidence for the effects of using 'set-asides' for primate protection within logging area on primate populations. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1497https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1497Tue, 17 Oct 2017 19:50:45 +0100Collected Evidence: Collected Evidence: Work inward from barriers or boundaries (e.g. river) to avoid pushing primates toward an impassable barrier or inhospitable habitat We found no evidence for the effects of working inward from barriers or boundaries to avoid pushing primates toward an impassable barrier or inhospitable habitat on primate populations. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1498https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1498Tue, 17 Oct 2017 19:51:56 +0100Collected Evidence: Collected Evidence: Install boardwalks/paths to prevent trampling We found no studies that evaluated the effects, on peatland vegetation, of installing boardwalks to prevent trampling. ‘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%2F1753https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1753Mon, 27 Nov 2017 21:32:35 +0000Collected Evidence: Collected Evidence: Wear snowshoes to prevent trampling We found no studies that evaluated the effects, on peatland vegetation, of wearing snowshoes to prevent trampling. ‘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%2F1754https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1754Mon, 27 Nov 2017 21:32:51 +0000Collected Evidence: Collected Evidence: Breed bats in captivity to supplement wild populations affected by white-nose syndrome We found no studies that evaluated the effects of breeding bats in captivity to supplement wild populations affected by white-nose syndrome. ‘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%2F2009https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2009Wed, 05 Dec 2018 15:41:19 +0000Collected Evidence: Collected Evidence: Prevent pollution from sewage treatment facilities from entering watercourses We found no studies that evaluated the effects of preventing pollution from sewage treatment facilities from entering watercourses 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%2F2010https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2010Wed, 05 Dec 2018 16:27:06 +0000Collected Evidence: Collected Evidence: Offset habitat loss from human activity by restoring or creating habitats elsewhere Two studies examined the effects of offsetting habitat loss from human activity by restoring or creating habitats elsewhere on subtidal benthic invertebrate populations. One study was in the Delaware Bay (USA), the other in the Persian Gulf (Kuwait).   COMMUNITY RESPONSE (1 STUDY) Overall richness/diversity (1 study): One study in the Persian Gulf found that an area of low ecological value restored to offset habitat lost to land reclamation was colonized by over 198 invertebrate species. POPULATION RESPONSE (0 STUDIES) OTHER (1 STUDY) Biological production (1 study): One study in Delaware Bay found that an artificial reef built to offset lost soft-sediment habitat had higher annual secondary production/unit area from sessile invertebrates, but lower total annual secondary production, compared to habitat similar to that lost. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2265https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2265Wed, 23 Oct 2019 11:03:46 +0100Collected Evidence: Collected Evidence: Transplant/release captive-bred or hatchery-reared species - Transplant/release crustaceans Five studies examined the effects of transplanting or releasing hatchery-reared crustacean species on their wild populations. Four examined lobsters in the North Sea (Germany, Norway, UK), and one examined prawns in the Swan-Canning Estuary (Australia).   COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (5 STUDIES) Crustacean abundance (1 study): One study in the Swan-Canning Estuary  found that after releasing hatchery-reared prawn larvae into the wild, the abundance of egg-bearing female prawns increased. Crustacean reproductive success (3 studies): Two studies (one controlled) in the North Sea found that after their release, recaptured hatchery-reared female lobsters carried eggs, and the number, size and developmental stage of eggs were similar to that of wild females. One study in the Swan-Canning Estuary  found that after releasing hatchery-reared prawn larvae into the wild the overall population fecundity (egg production/area) increased. Crustacean survival (2 studies): Two studies in the North Sea found that 50–84% and 32–39% of hatchery-reared lobsters survived in the wild after release, up to eight and up to five years, respectively. Crustacean condition (4 studies): Two studies in the North Sea found that hatchery-reared lobsters grew in the wild after release. One controlled study in the North Sea found that after release into the wild, hatchery-reared female lobsters had similar growth rates as wild females. One study in the North Sea found that after releasing hatchery-reared lobsters, no recaptured lobsters displayed signs of “Black Spot” disease, and 95% had developed a crusher-claw. One study in the Swan-Canning Estuary  found that after releasing hatchery-reared prawn larvae into the wild, the size of egg-bearing female prawns increased. BEHAVIOUR (1 STUDY) Crustacean movement (1 study): One controlled study in the North Sea found that after release into the wild, hatchery-reared female lobsters had similar movement patterns as wild females. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2266https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2266Wed, 23 Oct 2019 12:11:24 +0100Collected Evidence: Collected Evidence: Release captive-bred mammals into fenced areas Fourteen studies evaluated the effects of releasing captive-bred mammals into fenced areas. Nine studies were in Australia and one each was in Jordan, South Africa, the USA, Saudi Arabia and Senegal. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (14 STUDIES) Abundance (5 studies): Four studies (one replicated) and a review in Australia, Jordan and Senegal found that after releasing captive-bred animals into fenced areas, a population of burrowing bettongs increased, a population of Arabian oryx increased six-fold in 12 years, a population of dorcas gazelle almost doubled over four years, three populations of eastern barred bandicoot initially increased and abundance of eastern barred bandicoots increased. Reproductive success (6 studies): Four studies and a review in South Africa, Australia, Saudi Arabia and Senegal found that following release of captive-bred animals into fenced areas (in some cases with other associated management), African wild dogs, three populations of eastern barred bandicoot, dorcas gazelle and most female black-footed rock-wallabies reproduced, and Arabian gazelles started breeding in the year following the first releases. A study in Australia found that four of five mammal populations released into a predator-free enclosure and one released into a predator-reduced enclosure reproduced, whereas two populations released into an unfenced area with ongoing predator management did not survive to reproduce. Survival (10 studies): A study in Australia found that four of five mammal populations released into a predator-free enclosure and one population released into a predator-reduced enclosure survived, whereas two populations released into an unfenced area with ongoing predator management did not. Six studies (one controlled before-and-after study and two replicated studies) in Australia and the USA found that following release of captive-bred animals into fenced areas (in some cases with other associated management), a burrowing bettong population, three eastern barred bandicoot populations and over half of black-footed rock-wallabies survived between one and eight years, most captive-bred hare-wallabies survived at least two months, at least half of black-footed ferrets survived more than two weeks, and bandicoots survived at five of seven sites up to three years after the last release. One study in Australia found that following release into fenced areas, a captive-bred population of red-tailed phascogales survived for less than a year. A study in South Africa found that captive-bred African wild dogs released into fenced reserves in family groups had high survival rates. A randomized, controlled study in Australia found that captive-bred eastern barred bandicoots released into a fenced reserve after time in holding pens had similar post-release survival compared to bandicoots released directly from captivity. Condition (1 study): A randomized, controlled study in Australia found that captive-bred eastern barred bandicoots released into a fenced reserve after time in holding pens had similar post-release body weight compared to those released directly from captivity. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2521https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2521Mon, 08 Jun 2020 09:55:37 +0100Collected Evidence: Collected Evidence: Modify culverts to make them more accessible to mammals One study evaluated the effects of modifying culverts to make them more accessible to mammals. This study was in the USA. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (1 STUDY) Use (1 study): A replicated, site comparison study in the USA found that modified culverts (with a dry walkway, open-air central section and enlarged entrances) were used more by bobcats to make crossings than were unmodified culverts. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2522https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2522Mon, 08 Jun 2020 10:38:29 +0100Collected Evidence: Collected Evidence: Set and enforce vessel speed limits Two studies evaluated the effects on marine and freshwater mammals of setting and enforcing vessel speed limits. One study was in the Indian River estuarine system (USA) and the other in the North Atlantic Ocean (USA). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (2 STUDIES) Survival (2 studies): One before-and-after study in the Indian River estuarine system found similar numbers of manatee deaths before and after vessel speed limits were set in ‘zones’, but fewer deaths were recorded after speed limits were set and enforced in all areas. One before-and-after study in the North Atlantic Ocean found that setting vessel speed limits during specific periods in key habitats resulted in fewer North Atlantic right whale deaths caused by collisions. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2777https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2777Thu, 04 Feb 2021 15:48:43 +0000Collected Evidence: Collected Evidence: Introduce and enforce legislation to prevent intentional killing of mammals at wild fisheries We found no studies that evaluated the effects of introducing and enforcing legislation to prevent intentional killing of mammals at wild fisheries. ‘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%2F2778https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2778Thu, 04 Feb 2021 15:51:27 +0000Collected Evidence: Collected Evidence: Lower water level to restore degraded brackish/saline swampsWe found no studies that evaluated the effects, on vegetation, of lowering the water level to restore degraded brackish/saline swamps.   ‘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%2F3033https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3033Wed, 31 Mar 2021 15:20:55 +0100Collected Evidence: Collected Evidence: Facilitate tidal exchange to restore degraded freshwater marshesWe found no studies that evaluated the effects, on vegetation, of facilitating tidal exchange to restore degraded freshwater marshes.   ‘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%2F3034https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3034Wed, 31 Mar 2021 19:33:44 +0100Collected Evidence: Collected Evidence: Create mounds or hollows before planting trees/shrubs: brackish/saline wetlands One study evaluated the effects, on vegetation, of creating mounds or hollows in brackish/saline wetlands before planting trees/shrubs. The study was in Brazil. VEGETATION COMMUNITY   VEGETATION ABUNDANCE   VEGETATION STRUCTURE   OTHER Survival (1 study): One replicated, controlled study in a degraded coastal swamp in Brazil reported that planting tree seedlings into mounds had mixed effects on survival over three years, depending on the species. Growth (1 study): The same study reported that tree seedlings planted into mounds typically grew at a similar rate, over three years, to seedlings planted at ground level. Growth was measured in terms of diameter, height and canopy area. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3289https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3289Sat, 10 Apr 2021 17:35:23 +0100Collected Evidence: Collected Evidence: Remove surface soil/sediment (before planting)We found no studies that evaluated the effects, on vegetation, of removing surface soil/sediment before planting emergent marsh/swamp plants.   ‘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%2F3290https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3290Sat, 10 Apr 2021 20:04:01 +0100Collected Evidence: Collected Evidence: Establish temporary fishery closures Three studies evaluated the effects of establishing temporary fishery closures on reptile populations. Two studies were in the USA and one was in Brazil. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (3 STUDIES) Abundance (1 study): One site comparison study in Brazil found that areas where a fishing agreement was implemented that involved seasonal fishing restrictions along with a wider set of measures had more river turtles than areas that did not implement the agreement.  Survival (2 studies): One replicated, before-and-after study in the USA found that during seasonal closures of shrimp trawling there were fewer lethal strandings of loggerhead and Kemp’s ridley turtles. One study in the USA found that following the re-opening of a swordfish long-line fishery with turtle catch limits in place, loggerhead turtle bycatch reached the annual catch limit in two of three years, and when the limit was reached the fishery was closed for the rest of the year. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3545https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3545Tue, 07 Dec 2021 17:27:09 +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: Recover eggs from injured or dead reptiles Two studies evaluated the effects of recovering eggs from injured or dead reptiles on their populations. One study was in each of the USA and Columbia. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (2 STUDIES) Reproductive success (2 studies): One replicated, controlled study in Columbia found that eggs recovered from harvested Magdalena river turtles had similar hatching success compared to both relocated and natural turtle nests. One replicated study in the USA found that 64% of eggs recovered from road-killed red-eared sliders hatched successfully. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3801https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3801Wed, 15 Dec 2021 19:33:27 +0000Collected Evidence: Collected Evidence: Create artificial nests or nesting sites Nine studies evaluated the effects of creating artificial nests or nesting sites on reptile populations. Three studies were in the USA and one study was in each of the Galápagos, Spain, China, Reunion Island, Canada and Jamaica. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (6 STUDIES) Reproductive success (6 studies): Two studies (including one before-and-after study) on Reunion Island and Jamaica found that the number of Reunion day gecko eggs and Jamaican iguana hatchlings at artificial nesting sites increased over time. One of two replicated, controlled studies in Canada and the USA found that hatching success of eggs from four species of freshwater turtle moved to artificial nest sites was higher than for eggs left in natural sites. The other study found that hatching success of diamondback terrapin nests in artificial nest sites compared to natural sites varied depending on the substrate used. One study in Spain found that eggs laid in an artificial nest by an Iberian wall lizard hatched and those placed in artificial nests had high hatching success. One replicated study in the USA found that fewer diamondback terrapin nests were predated in artificial nesting mounds protected with an electric wire than in mounds with no wire. BEHAVIOUR (8 STUDIES) Use (8 studies): Four of seven studies (including one replicated, controlled study) in the Galápagos, Spain, Reunion Island, Canada, the USA and Jamaica found that artificial nest sites were used by captive Galápagos giant tortoises, Iberian wall lizards, four species of freshwater turtle and diamondback terrapins. Two studies found that use of artificial nest sites increased over time for Reunion day geckos and Jamaican iguanas. The other study found that artificial nest sites were used infrequently by northern map turtles. One study in China found that artificial nesting materials were used by some Chinese alligators. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3802https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3802Mon, 20 Dec 2021 10:04:37 +0000
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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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