Collected Evidence: Collected Evidence: Alter artificial nest sites to discourage brood parasitismA replicated trial from Puerto Rico found that brood parasitism levels were extremely high across all nest box designs tested.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F446https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F446Thu, 23 Aug 2012 16:06:05 +0100Collected Evidence: Collected Evidence: Alter habitat to encourage birds to leave an areaA single before-and-after study in the USA found that an entire Caspian tern Sterna caspia population moved following (amongst other interventions) the alteration of nesting habitat at the old colony site.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F587https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F587Sat, 06 Oct 2012 22:42:09 +0100Collected Evidence: Collected Evidence: Allow natural regeneration of ground cover beneath perennial cropsNatural enemies on crop trees and vines: Five studies (including one replicated, randomised, controlled test) from Australia, China, Italy and Portugal compared natural and bare ground covers by measuring numbers of natural enemies in fruit tree or vine canopies. Three found effects varied between groups of natural enemies, two found no difference. Two studies from Australia and France compared natural to sown ground cover and found no effect on enemies in crop canopies. Natural enemies on the ground: Five studies (including three replicated, randomised, controlled trials) from Australia, Canada, China, France, and Spain compared natural and bare ground covers by measuring natural enemies on the ground. Two studies found more natural enemies in natural ground cover, but in one the effects were only short-term for most natural enemy groups. Three studies found mixed effects, with higher numbers of some natural enemy groups but not others. Two studies compared natural and sown ground covers, one study found more natural enemies and one found no effect. Pests and crop damage: Four studies (three controlled, one also replicated and randomised) from Italy, Australia and China measured pests and crop damage in regenerated and bare ground covers. Two studies found fewer pests, whilst two studies found effects on pests and crop damage varied for different pest or disease groups. One study found more pests in natural than in sown ground covers. Crops studied were apple, grape, lemon, olive and pear.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F720https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F720Thu, 30 May 2013 11:41:45 +0100Collected Evidence: Collected Evidence: Aerobic training A randomised, replicated, controlled study in Norway found higher survival rates in salmon exposed to infectious pancreatic necrosis if they had undergone aerobic training. Interval training was more effective than continuous training. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F740https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F740Mon, 03 Jun 2013 15:39:10 +0100Collected Evidence: Collected Evidence: Alter lighting A replicated, controlled study in Norway reported lower numbers of lice on salmon kept in low intensity artificial light or natural lighting. The more intense the artificial light was, the higher the number of lice found on fish. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F741https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F741Mon, 03 Jun 2013 15:41:00 +0100Collected Evidence: Collected Evidence: Alter cage size A replicated study in Australia recorded lower levels of amoebic gill disease in salmon kept within larger compared to smaller cages. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F742https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F742Mon, 03 Jun 2013 15:46:43 +0100Collected Evidence: Collected Evidence: Adopt protected species legislation (impact on forest management) We found no evidence of the effects of adopting protected species legislation on forests. '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%2F1201https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1201Thu, 19 May 2016 13:21:26 +0100Collected Evidence: Collected Evidence: Allow primates to adapt to local habitat conditions for some time before introduction to the wild Two studies in Brazil and Thailand found that reintroduced primate populations were smaller after 12-17 months and one study in Belize found primate populations increased five years after allowing individuals to adapt to local habitat conditions before introduction into the wild, alongside other interventions. One study found that a reintroduced population of black howler monkeys had a birth rate of 20% after they were allowed to adapt to local habitat conditions before introduction into the wild, along with other interventions. Seven studies in Brazil, Madagascar, Malaysia, French Guiana, South Africa found that a minority of primates survived for at least 15 weeks to 12 years after allowing them to adapt to local habitat conditions before introduction into the wild, along with other interventions. Four studies in Belize, Brazil, Gabon, South Africa found that the majority of primates survived for at least four to 12 months. One study in Vietnam found that half of reintroduced pygmy slow lorises survived for at least two months. Two before-and-after studies in Gabon and the Republic of Congo found that a majority of western lowland gorillas survived for nine months to four years after allowing them to adapt to local habitat conditions before introduction into the wild, along with other interventions. Three studies in Liberia and the Congo found that a majority of chimpanzees survived for at least three to five years after allowing them to adapt to local habitat conditions before introduction into the wild, along with other interventions. One before-and-after study in Uganda found that a chimpanzee repeatedly returned to human settlements after allowing it to adapt to local habitat conditions before introduction into the wild, along with other interventions. A study in Indonesia found that Sumatran orangutans that were allowed to adapt to local habitat conditions before introduction performed less well than individuals that were directly released into the forest, alongside other interventions. One controlled study in Indonesia found that after being allowed to adapt to local habitat conditions a pair of introduced Bornean agile gibbons had a similar diet to wild gibbons. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1564https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1564Fri, 20 Oct 2017 10:08:36 +0100Collected Evidence: Collected Evidence: Allow shrubland to regenerate without active management Five before-and-after trials (two of which were replicated) in the USA, UK, and Norway, found that allowing shrubland to recover after fire without any active management increased shrub cover or biomass. One replicated, paired, site comparison in the USA found that sites that were allowed to recover without active restoration had similar shrub cover to unburned areas. One controlled, before-and-after trial in the USA found no increase in shrub cover. One before-and-after trial in Norway found an increase in heather height. One before-and-after trial in Spain found that there was an increase in seedlings for one of three shrub species. Two replicated, randomized, controlled, before-and-after trials in Spain and Portugal found that there was an increase in the cover of woody plant species. One before-and-after study in Spain found that cover of woody plants increased, but the number of woody plant species did not. One replicated, before-and-after study in South Africa found that the height of three protea species increased after recovery from fire. One before-and-after trial in South Africa found that there was an increase in vegetation cover, but not in the number of plant species. One before-and-after trial in South Africa found an increase in a minority of plant species.  Two before-and-after trials in the USA and UK found that allowing shrubland to recover after fire without active management resulted in a decrease in grass cover or biomass. One controlled, before-and-after trial in the USA found an increase in the cover of a minority of grass species. One before-and-after study in Spain found that cover of herbaceous species declined. One replicated, before-and-after study in the UK found mixed effects on cover of wavy hair grass. One controlled, before-and-after trial in the USA found no increase in forb cover. One replicated, randomized, controlled before-and-after trial in Spain found that herb cover declined after allowing recovery of shrubland after fire. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1679https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1679Mon, 23 Oct 2017 09:08:16 +0100Collected Evidence: Collected Evidence: Adopt ecotourism principles/create an ecotourism site We found no studies that evaluated the effects, on peatland vegetation, of adopting ecotourism principles or creating an ecotourism site. ‘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%2F1755https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1755Mon, 27 Nov 2017 21:33:27 +0000Collected Evidence: Collected Evidence: Adopt voluntary agreements to protect peatlands We found no studies that evaluated the effects, on peatland habitats, of adopting voluntary agreements to protect them. ‘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%2F1798https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1798Tue, 28 Nov 2017 08:27:20 +0000Collected Evidence: Collected Evidence: Allow sustainable use of peatlands We found no studies that evaluated the effects, on peatland habitats, of allowing sustainable use. ‘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%2F1801https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1801Tue, 28 Nov 2017 08:28:04 +0000Collected Evidence: Collected Evidence: Adopt zero burning policies near peatlands We found no studies that evaluated the effects, on peatland vegetation, of adopting zero burning policies 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%2F1856https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1856Wed, 29 Nov 2017 10:54:22 +0000Collected Evidence: Collected Evidence: Airborne translocation of mammals using parachutes One study evaluated the effects of airborne translocation of mammals using parachutes. This study was in the USA. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Survival (1 study): A study in the USA found that at least some North American beavers translocated using parachutes established territories and survived over one year after release. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2466https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2466Wed, 03 Jun 2020 09:31:50 +0100Collected Evidence: Collected Evidence: Allow forest to regenerate naturally following logging One study evaluated the effects on mammals of allowing forest to regenerate naturally following logging. This study was in Canada. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Abundance (1 study): A replicated, site comparison study in Canada found that, natural forest regeneration increased moose numbers relative to more intensive management in the short- to medium-term but not in the longer term. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2634https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2634Fri, 12 Jun 2020 12:49:45 +0100Collected Evidence: Collected Evidence: Allow only small-scale, traditional (artisanal) fishing One study examined the effects of allowing only small-scale traditional (artisanal) fishing in an area on marine fish populations. The study was in the Adriatic Sea (Italy). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (0 STUDIES) OTHER (1 STUDY) Commercial catch abundance (1 study): One site comparison study in the Adriatic Sea found that a marine protected area zone allowing only artisanal fishing activity for three years had higher overall commercial catch rates of five of seven species compared to unprotected areas openly fished. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2678https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2678Fri, 27 Nov 2020 16:09:39 +0000Collected Evidence: Collected Evidence: Allow periodic fishing only One study examined the effects of allowing fishing only periodically in an area on marine fish populations. The study was in the Coral Sea (Vanuatu). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Abundance (1 study): One replicated, paired, site comparison study in the Coral Sea found that protected areas fished only for short periods over an 18 month to six-year period, had greater biomass than openly fished areas and similar fish biomass as areas permanently closed to fishing for six years. BEHAVIOUR (0 STUDIES) OTHER (1 STUDY) Catch abundance (1 study): One replicated, paired, site comparison study in the Coral Sea found that protected areas only fished for short periods over an 18 month to six year period, had higher fish catch rates than openly fished areas. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2679https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2679Fri, 27 Nov 2020 16:20:22 +0000Collected Evidence: Collected Evidence: Adopt ecotourism principles/create an ecotourism siteWe found no studies that evaluated the effects, on marsh/swamp vegetation, of adopting ecotourism principles or creating an ecotourism site.   ‘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%2F3025https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3025Wed, 31 Mar 2021 14:46:14 +0100Collected Evidence: Collected Evidence: Allow plants to adjust to field conditions before plantingWe found no studies that evaluated the effects of allowing emergent vegetation to adjust to field conditions before planting in wetlands.   ‘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%2F3349https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3349Sun, 11 Apr 2021 16:56:48 +0100Collected Evidence: Collected Evidence: Alter incubation temperatures to achieve optimal/desired sex ratio: Sea turtles One study evaluated the effects of altering incubation temperatures to achieve optimal/desired sex ratios on sea turtles. This study was in Canada. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Reproductive success (1 study): One replicated study in Canada reported that hatching success of two clutches of artificially incubated green turtle eggs was 8% and 62%. BEHAVIOUR (0 STUDIES) OTHER (1 STUDY): Offspring sex ratio (1 study): One replicated study in Canada found that incubating green turtle eggs at higher temperatures resulted in more females hatchlings. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3761https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3761Tue, 14 Dec 2021 16:09:09 +0000Collected Evidence: Collected Evidence: Alter incubation temperatures to achieve optimal/desired sex ratio: Tortoises, terrapins, side-necked & softshell turtles Eight studies evaluated the effects of altering incubation temperatures to achieve optimal/desired sex ratios on tortoise, terrapin, side-necked and softshell turtle populations. Four studies were in the USA, two were in Columbia and one was in each of Brazil and the Galápagos. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (5 STUDIES) Reproductive success (5 studies): Four studies (including two replicated studies) in the USA, Colombia and the Galápagos found that hatching success of alligator snapping turtle, Magdalena river turtle, western pond turtle and Española giant tortoise eggs varied across the range of temperatures tested. One controlled study in Brazil found that Amazon River turtle nests covered with black plastic sheeting had lower hatching success than uncovered nests. BEHAVIOUR (0 STUDIES) OTHER (8 STUDIES): Offspring sex ratio (8 studies): Seven studies (including three replicated, randomized studies) in the USA, Colombia and the Galápagos found that hatchling sex ratio of turtles and tortoises was affected by incubation temperature, and that warmer temperatures resulted in more female hatchlings. One controlled study in Brazil found that Amazon River turtle nests covered with black plastic sheeting produced more female hatchlings than uncovered nests. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3762https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3762Tue, 14 Dec 2021 16:12:00 +0000Collected Evidence: Collected Evidence: Alter incubation temperatures to achieve optimal/desired sex ratio: Snakes & lizards Four studies evaluated the effects of altering incubation temperatures to achieve optimal/desired sex ratios on snake and lizard populations. Two studies were in each of the USA and China. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (3 STUDIES) Reproductive success (3 studies): Two replicated studies (including one randomized study) in China and the USA found that toad-headed agama hatching success was lowest at the highest incubation temperature tested and southern alligator lizard hatching success was highest at intermediate temperatures.One randomized study in the USA found that survival of garter snake offspring was highest when females were maintained at intermediate temperatures. BEHAVIOUR (0 STUDIES) OTHER (4 STUDIES): Offspring sex ratio (4 studies): Three replicated studies (including two randomized studies) in China and the USA found that hatchling sex ratio of stripe-tailed ratsnakes, toad-headed agamas and southern alligator lizard was not affected by incubation temperature. One randomized study in the USA found that sex ratio of live garter snake offspring was not affected by the temperature females were maintained at. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3763https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3763Tue, 14 Dec 2021 16:36:15 +0000Collected Evidence: Collected Evidence: Alter incubation temperatures to achieve optimal/desired sex ratio: Crocodilians Three studies evaluated the effects of altering incubation temperatures to achieve optimal/desired sex ratios on crocodilian populations. Two studies were in Argentina and one was in China. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (2 STUDIES) Reproductive success (2 studies): Two replicated, randomized study in Argentina found that hatching success of broad-snouted caiman eggs was similar across all temperatures tested. BEHAVIOUR (0 STUDIES) OTHER (3 STUDIES): Offspring sex ratio (3 studies): Two replicated, randomized studies in Argentina found that hatchling sex ratio of broad-snouted caimans was affected by temperature, and that warmer temperatures resulted in fewer females. One replicated study in China found that exposing Chinese alligator eggs to short periods of high temperatures during incubation resulted in fewer female hatchlings. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3764https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3764Tue, 14 Dec 2021 16:44:08 +0000Collected Evidence: Collected Evidence: Alter incubation temperatures to achieve optimal/desired sex ratio: Tuatara Two studies evaluated the effects of altering incubation temperatures to achieve optimal/desired sex ratios on tuatara populations. Both studies were in New Zealand. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (0 STUDIES) OTHER (2 STUDIES): Offspring sex ratio (2 studies): Two replicated studies (including one controlled study) in New Zealand found that hatchling sex ratio of tuatara was affected by temperature, and that warmer temperatures resulted in more males. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3765https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3765Tue, 14 Dec 2021 17:00:12 +0000Collected Evidence: Collected Evidence: Alter mowing regimes on greenspaces and road verges Seven studies evaluated the effects of altering mowing regimes on greenspaces and road verges on butterflies and moths. One study was in each of Finland, the Netherlands, Poland, Germany, the UK, Canada and Sweden. COMMUNITY RESPONSE (3 STUDIES) Richness/diversity (3 studies): Two replicated, paired, controlled studies in Germany and the UK found that less frequently mown or unmown urban greenspaces had a higher species richness and diversity of butterflies and moths than more frequently mown areas. One replicated, site comparison study in Canada found that the management of road verges (and land under power lines) did not affect the species richness of butterflies. POPULATION RESPONSE (4 STUDIES) Abundance (3 studies): Two replicated studies (including one paired, controlled study) in the UK and Canada found that unmown public parks and road verges (and land under power lines) had a higher abundance of all adult butterflies and pearl crescent and northern pearl crescent butterflies than regularly mown areas, but the abundance of other butterflies on the road verges (and under power lines) was similar between mown and unmown areas in the second study. One study in Finland found that roadsides mown in late summer had more ringlet butterflies than those mown in mid-summer. Survival (1 study): One replicated, site comparison study in Poland found that road verges mown less frequently, or later in summer, had fewer dead butterflies killed by traffic than more frequently or earlier mown verges. BEHAVIOUR (2 STUDIES) Use (2 studies): One replicated, site comparison study in Sweden reported that less frequently mown urban grasslands were more frequently occupied by scarce copper butterflies than more frequently mown grasslands. One replicated, randomized, controlled study in the Netherlands found that butterflies were recorded on verges which were mowed once or twice a year and those which were not mowed, but on mowed verges butterflies were only recorded on those where hay was removed. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3841https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3841Mon, 04 Jul 2022 15:45:31 +0100
What Works 2021 cover

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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