Collected Evidence: Collected Evidence: Use coloured baits to reduce accidental mortality during predator control Two replicated and controlled trials in the USA found that dyed baits were consumed at significantly lower rates than control baits. A replicated, randomised and controlled trial in Australia found no differences in consumption rates of dyed and control baits. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F182https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F182Fri, 01 Jun 2012 16:40:17 +0100Collected Evidence: Collected Evidence: Use collar-mounted devices to reduce predation Two replicated randomised and controlled studies in the UK and Australia found that significantly fewer birds were returned by cats wearing collars with various anti-hunting devices, compared to controls. A replicated, randomised and controlled study from the UK found no significant differences between different devices. Both UK studies found that collars were easily lost.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F416https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F416Thu, 16 Aug 2012 15:27:05 +0100Collected Evidence: Collected Evidence: Use copper strips to exclude snails from nestsA single small, before-and-after study in Mauritius found no snail-caused chick mortality in 2004–7 after the installation of copper strips at seven echo parakeet Psittacula eques nest holes, compared to four fatalities in 2003–4.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F447https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F447Thu, 23 Aug 2012 16:08:25 +0100Collected Evidence: Collected Evidence: Use captive breeding to increase or maintain populations of tinamousA replicated study from Costa Rica over three years found that great tinamous Tinamus major successfully bred in captivity, with similar reproductive success to wild birds.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F588https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F588Sat, 06 Oct 2012 22:48:42 +0100Collected Evidence: Collected Evidence: Use captive breeding to increase or maintain populations of seabirdsA study from Spain over five years found that a single pair of Audouin’s gulls, Larus audouinii, successfully bred in captivity.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F589https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F589Sat, 06 Oct 2012 22:52:51 +0100Collected Evidence: Collected Evidence: Use captive breeding to increase or maintain populations of storks and ibises We captured a small study and a review describing the captive breeding of storks (Ciconiidae) and a study and a review describing the breeding of northern bald ibis, Geronticus eremita. Both studies on storks were from the USA. The small study found that a pair bred; the review found that only seven of 19 species had been successfully bred in captivity. A review of bald ibis conservation found that 1,150 birds had been produced in captivity from 150 founders over 20 years. However, some projects had failed, and a study from Turkey found that captive birds had lower productivity than wild birds.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F595https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F595Sat, 13 Oct 2012 14:54:55 +0100Collected Evidence: Collected Evidence: Use captive breeding to increase or maintain populations of songbirds A replicated study from Australia and two small studies from the USA found that three species of songbird were successfully bred in captivity. Four out of five pairs of wild-bred, hand-reared puaiohi, Myadestes palmeri, formed pairs and laid a total of 39 eggs in 1998 and a breeding population of helmeted honeyeaters, Lichenostomus melanops cassidix, was successfully established through a breeding programme. Only one pair of loggerhead shrikes, Lanius ludovicianus, formed pairs from eight wild birds caught and their first clutch died.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F598https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F598Sat, 13 Oct 2012 15:24:35 +0100Collected Evidence: Collected Evidence: Use chemicals to attract natural enemiesParasitism and predation (by natural enemies): One review and two of five studies from Asia, Europe and North America found that attractive chemicals increased parasitism. Two studies, including one randomised, replicated, controlled trial, found greater parasitism for some but not all chemicals, crops, sites or years and one study found no effect. One study showed that parasites found pests more rapidly. One study found lower egg predation by natural predators. Natural enemies: Five of 13 studies from Africa, Asia, Australasia, Europe and North America found more natural enemies while eight (including seven randomised, replicated, controlled trials) found positive effects varied between enemy groups, sites or study dates. Four of 13 studies (including a meta-analysis) found more natural enemies with some but not all test chemicals. Two of four studies (including a review) found higher chemical doses attracted more enemies, but one study found lower doses were more effective and one found no effect. Pests: Three of nine studies (seven randomised, replicated, controlled) from Asia, Australasia, Europe and North America found fewer pests, although the effect occurred only in the egg stage in one study. Two studies found more pests and four found no effect. Crop damage: One study found reduced damage with some chemicals but not others, and one study found no effect. Yield: One study found higher wheat yields. Crops studied were apple, banana, bean, broccoli, Chinese cabbage, cotton, cowpea, cranberry, grape, grapefruit, hop, maize, oilseed, orange, tomato, turnip and wheat.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F754https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F754Thu, 08 Aug 2013 13:40:59 +0100Collected Evidence: Collected Evidence: Use clearcutting to increase understory diversity Eight of 12 studies (including three replicated, randomized, controlled studies) in Belgium, Brazil, Canada, China, Germany, Israel, spain and the USA found that clearcutting increased the cover and species richness of understory plants. Two found it decreased the density and species richness, and two found no effect or mixed effects. Three of six studies (including five replicated, randomized, controlled studies) in Brazil, Canada and Spain found that clearcutting increased the density and species richness of young trees. One found it decreased new tree density and two found no effect or mixed effects depending on the tree species. Three of nine studies (including four replicated, randomized, controlled studies) in Australia, Brazil4, Canada, Japan and the USA found that clearcutting decreased density, species richness and diversity of mature trees. One study found it increased trees species richness .Six studies found no effect or mixed effects on tree density, size and species richness and diversity.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1222https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1222Mon, 23 May 2016 08:58:48 +0100Collected Evidence: Collected Evidence: Use covers/barriers to control problematic plants We found no studies that evaluated the effects, on peatland vegetation, of using covers or barriers to control problematic 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%2F1775https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1775Mon, 27 Nov 2017 21:44:10 +0000Collected Evidence: Collected Evidence: Use collar-mounted devices on cats to reduce predation of bats We found no studies that evaluated the effects of using collar-mounted devices on cats to reduce predation of bats 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%2F2004https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2004Wed, 05 Dec 2018 15:30:20 +0000Collected Evidence: Collected Evidence: Use collar-mounted devices to reduce predation by domestic animals Five studies evaluated the effects on mammals of using collar-mounted devices to reduce predation by domestic animals. Three studies were in the UK, one was in Australia and one was in the USA. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (5 STUDIES) Survival (5 studies): Five replicated studies (including four randomized, controlled studies), in the UK, Australia and the USA, found that bells, a sonic device, and a neoprene flap (which inhibits pouncing) mounted on collars, and a brightly coloured and patterned collar all reduced the rate at which cats predated and returned home with mammals. In one of these studies, an effect was only found in autumn, and not in spring. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2332https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2332Thu, 21 May 2020 11:11:00 +0100Collected Evidence: Collected Evidence: Use conditioned taste aversion to reduce human-wildlife conflict in non-residential sites Two studies evaluated the effects on mammals of using conditioned taste aversion to reduce human-wildlife conflict in non-residential sites. Both studies were in the USA. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (0 STUDIES) OTHER (2 STUDIES) Human-wildlife conflict (2 studies): Two studies, in the USA, found that lacing foodstuffs with substances that induce illness led to these foods being avoided by coyotes and black bears.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2384https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2384Wed, 27 May 2020 15:03:03 +0100Collected Evidence: Collected Evidence: Use chili to deter crop damage by mammals to reduce human-wildlife conflict Seven studies evaluated the effects on elephants of using chili to deter crop damage to reduce human-wildlife conflict. Four studies were in Zimbabwe, two were in Kenya and one was in India. KEY COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (0 STUDIES) OTHER (7 STUDIES) Human-wildlife conflict (7 studies): Five of seven studies (including four replicated and two before-and-after studies), in Zimbabwe, Kenya and India, found that chill-based deterrents (chili-spray, chili smoke, chili fences and chili extract in a projectile, in some cases along with other deterrents) repelled elephants at least initially, whist two studies found that chili smoke (and in one case chili fences) did not reduce crop raiding. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2492https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2492Thu, 04 Jun 2020 14:22:19 +0100Collected Evidence: Collected Evidence: Use conditioned taste aversion to prevent non-target species from entering traps One study evaluated the effects on mammals of using conditioned taste aversion to prevent non-target species from entering traps. This study was in the USA. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (1 STUDY) Behaviour change (1 study): A replicated, controlled study in the USA found that using bait laced with lithium chloride reduced the rate of entry of San Clemente Island foxes into traps set for feral cats. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2536https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2536Mon, 08 Jun 2020 16:41:53 +0100Collected Evidence: Collected Evidence: Use chemical repellents along roads or railways Five studies evaluated the effects on mammals of using chemical repellents along roads or railways. Two studies were in Canada and one each was in Germany, Norway and Denmark. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (2 STUDIES) Survival (2 studies): Two studies (one before-and-after, one site comparison), in Germany and Norway, found that chemical-based repellents did not reduce collisions between ungulates and road vehicles or trains. BEHAVIOUR (4 STUDIES) Behaviour change (4 studies): Two of four studies (including three replicated, controlled studies), in Germany, Canada, and Denmark, found that chemical repellents, trialled for potential to deter animals from roads, did not deter ungulates. The other two studies found mixed results with repellents temporarily deterring some ungulate species in one study and one of three deterrents deterring caribou in the other. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2615https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2615Fri, 12 Jun 2020 08:24:14 +0100Collected Evidence: Collected Evidence: Use citizen surveillance to report illegal fishing We found no studies that evaluated the effects of using citizen surveillance to report illegal fishing 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%2F2741https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2741Tue, 02 Feb 2021 15:37:26 +0000Collected Evidence: Collected Evidence: Use cooling towers instead of once-through cooling systems We found no studies that evaluated the effects of using cooling towers instead of once-through cooling systems 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%2F2753https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2753Tue, 02 Feb 2021 16:56:13 +0000Collected Evidence: Collected Evidence: Use catch and hook protection devices on fishing gear Five studies evaluated the effects on marine mammals of using catch and hook protection devices on fishing gear. Two studies were in the South Pacific Ocean (Chile, Australia and Fiji), two were in the Indian Ocean (Seychelles, Madagascar) and one was in the Southwest Atlantic Ocean. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (0 STUDIES) OTHER (5 STUDIES) Reduction in entanglements/unwanted catch (1 study): One study in the South Pacific Ocean found that using cage or chain devices on fishing hooks resulted in fewer unwanted catches of toothed whales. Human-wildlife conflict (5 studies): Two of four studies (including three controlled and one before-and-after study) in the South Pacific Ocean, the Southwest Atlantic Ocean and the Indian Ocean found that net sleeves or cage and chain devices on fishing hooks reduced damage to fish catches by sperm whales, killer whales and toothed whales. The two other studies found that attaching ‘umbrella’ or ‘spider’ devices on fishing hooks did not reduce predation and/or damage to fish catches by sperm whales or toothed whales. One controlled study in the Indian Ocean found that attaching catch protection devices made from streamers to fishing lines reduced Indo-Pacific bottlenose and spinner dolphin predation on fish bait, but only during the first two trials. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2821https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2821Fri, 05 Feb 2021 15:18:24 +0000Collected Evidence: Collected Evidence: Use covers/barriers to control problematic plants: brackish/salt marshesWe found no studies that evaluated the effects, on vegetation, of using covers or barriers to control problematic plants in brackish/salt 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%2F3125https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3125Mon, 05 Apr 2021 09:58:54 +0100Collected Evidence: Collected Evidence: Use covers/barriers to control problematic plants: brackish/saline swampsWe found no studies that evaluated the effects, on vegetation, of using covers or barriers to control problematic plants in 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%2F3127https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3127Mon, 05 Apr 2021 09:59:17 +0100Collected Evidence: Collected Evidence: Use circle hooks instead of J-hooks Eleven studies evaluated the effects of using circle hooks instead of J-hooks on reptile populations. Five studies were in the Atlantic, three were in the Pacific and one study was in each of the Mediterranean, the Atlantic and North Pacific and the western North Atlantic, Azores, Gulf of Mexico and Ecuador. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (3 STUDIES) Survival (3 studies): Two studies (including one replicated, controlled, paired study) off the coast of Hawaii and in the north-east Atlantic Ocean found that survival of loggerhead and leatherback turtles and leatherback and hard-shell sea turtles caught by circle hooks or J-hooks was similar. One review of studies in five pelagic longline fisheries found that fewer sea turtles died when circle hooks were used compared to J-hooks in four of five fisheries. Condition (3 studies): Two replicated, controlled studies in the Mediterranean Sea and south-western Atlantic Ocean found that fewer immature loggerhead turtles and loggerhead turtles swallowed circle hooks compared to J-hooks. One before-and-after study off the coast of Hawaii found that a lower percentage of loggerhead and leatherback turtles were deeply hooked by circle hooks compared to J-hooks. BEHAVIOUR (0 STUDIES) OTHER (11 STUDIES) Unwanted catch (11 studies): Seven of 10 studies (including six replicated, controlled studies) in the Pacific, Atlantic, Atlantic and North Pacific and Mediterranean and one review of studies in five pelagic longline fisheries found that circle hooks or circle hooks and tuna hooks caught fewer sea turtles than J-hooks, or that non-offset G-style circle hooks caught fewer leatherback and hard-shell sea turtles that offset J-Hooks. One of these studies also found that circle hooks caught slightly larger loggerhead turtles than J-hooks, and one also found that offset Gt-style circle hooks caught a similar number of leatherback and hard-shell sea turtles compared to offset J-hooks. One study found that circle hooks caught a similar number of leatherback, green and olive ridley turtles compared to J-hooks. One study found that fish-baited circle hooks caught fewer loggerhead and leatherback turtles than squid-baited J-hooks. The review found mixed effects of using circle hooks compared to J-hooks on unwanted catch of sea turtles depending on the fishery. The other study found mixed effects of using circle hooks or J-hooks in combination with squid or fish bait on the number of loggerhead and leatherback turtles that were caught. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3559https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3559Wed, 08 Dec 2021 14:21:43 +0000Collected Evidence: Collected Evidence: Use catch and hook protection devices We found no studies that evaluated the effects of using catch and hook protection devices 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%2F3582https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3582Wed, 08 Dec 2021 15:27:59 +0000Collected Evidence: Collected Evidence: Use collar-mounted devices to reduce predation by domestic animals Two studies evaluated the effects of using collar-mounted devices to reduce predation by domestic animals on reptile populations. Both studies were in Australia. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (2 STUDIES) Survival (2 studies): One of two replicated, randomized studies (including one before-and-after and one controlled study) in Australia found that cats wearing collar mounted neoprene bibs, with or without a bell, caught a similar number of combined reptiles and amphibians compared to cats not wearing them. The other study found that cats wearing collar mounted ruffs brought home fewer combined reptiles and amphibians than cats not wearing them. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3683https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3683Fri, 10 Dec 2021 15:42:21 +0000Collected Evidence: Collected Evidence: Use conditioned taste aversion to prevent carnivorous reptiles from eating toxic invasive cane toads Two studies evaluated the effects on reptile populations of using conditioned taste aversion to prevent carnivorous reptiles from eating toxic invasive cane toads. Both studies were in Australia. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (2 STUDIES) Survival (2 studies): One of two replicated, controlled studies in Australia found that survival of yellow-spotted goannas subjected to conditioned taste aversion was higher at one of two sites than those that were not treated. The other study found that survival of bluetongue skinks given a high dose was higher than those given a low dose, but similar to skinks receiving no dose. BEHAVIOUR (1 STUDY) Behaviour change (1 study): One replicated, controlled study in Australia found that yellow-spotted goannas subjected to conditioned taste aversion were less likely to eat cane toads than those that were not treated. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3700https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3700Fri, 10 Dec 2021 18:54:41 +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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