Conservation Evidence: Evidence Data

Collected Evidence: Collected Evidence: Translocate toads Two of four studies (including two replicated studies) in Denmark, Germany, the UK and USA found that translocating eggs and/or adults established common toad breeding populations. One found populations of garlic toads established at two of four sites. One found that breeding populations of boreal toads were not established. One before-and-after study in Denmark found that translocating green toad eggs to existing populations, along with aquatic and terrestrial habitat management, increased population numbers. Three studies (including one before-and-after study) in Germany, Italy and the USA found that 33–100% of translocated adult toads reproduced, 19% survived up to six years or some metamorphs survived over winter. One replicated study in South Africa found that translocated Cape platanna metamorphs survived up to 23 years at one of four sites. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F855https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F855Fri, 06 Sep 2013 12:17:03 +0100Collected Evidence: Collected Evidence: Translocate wood frogs Two studies (including one replicated study) in the USA found that translocated wood frog eggs established breeding populations in 25–50% of created ponds. One replicated study in the USA found that translocated wood frog eggs hatched and up to 57% survived as tadpoles in enclosures in restored ponds. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F856https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F856Fri, 06 Sep 2013 13:19:09 +0100Collected Evidence: Collected Evidence: Translocate great crested newts Four of six studies (including one review and one replicated study) in the UK found that translocated great crested newts maintained or established breeding populations. The review found that populations were present one year after release in 37% of cases and one study found that although translocations maintained a population in the short term, within three years breeding failed in 48% of ponds. One systematic review of 31 great crested newt studies found that there was no conclusive evidence that mitigation that included translocations resulted in self-sustaining populations. One review in the UK found that great crested newts reproduced following 56% of translocations, in some cases there was also release of head-started larvae and/or habitat management. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F858https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F858Fri, 06 Sep 2013 13:32:49 +0100Collected Evidence: Collected Evidence: Translocate natterjack toads Three studies (including one review) in France and the UK found that translocated natterjack toad eggs, tadpoles, juveniles or adults established breeding populations at one site or in 30–70% of cases, some of which also released head-started or captive-bred animals or included habitat management. The review found that re-establishing toads on dune or saltmarsh habitat was more successful than on heathland. One replicated study in the UK found that natterjack toad populations increased at sites established by translocations, particularly with replicated translocations of wild rather than captive-bred toads. Two replicated, before-and-after studies in Estonia and the UK found that translocating natterjack toad eggs or tadpoles resulted in breeding at 8–70% of sites, some of which had been restored. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F859https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F859Fri, 06 Sep 2013 13:48:11 +0100Collected Evidence: Collected Evidence: Translocate salamanders (including newts) One review and three before-and-after studies in the UK and USA found that translocated eggs or adults established breeding populations of salamanders or smooth newts. One replicated, before-and-after study in the USA found that one of two salamander species reproduced following translocation of eggs, tadpoles and metamorphs. One before-and-after study in the USA found that translocated salamander eggs hatched and tadpoles had similar survival rates as in donor ponds. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F860https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F860Fri, 06 Sep 2013 14:03:10 +0100Collected Evidence: Collected Evidence: Translocate frogs Eight of ten studies (including five replicated studies) in New Zealand, Spain, Sweden, the UK and USA found that translocating frog eggs, juveniles or adults established breeding populations at 100% or 79% of sites. Two found that breeding populations of two species were initially established but went extinct within five years or did not establish. Five studies (including one replicated study) in Italy, New Zealand and the USA found that translocated juveniles or adults survived the winter, had high survival, survived up to two years, or up to eight years with predator exclusion. One study in the USA found that survival was lower for Oregon spotted frogs translocated as adults compared to eggs and lower than that of resident frogs. Five studies (including three replicated studies) in Canada, New Zealand and the USA found that translocations of eggs, juveniles or adults resulted in little or no breeding at one or three of four sites. Two studies (including one before-and-after study) in the USA found that 60–100% of translocated frogs left the release site and 35–73% returned to their original pond within 1–32 days. Two before-and-after studies New Zealand and the USA found that frogs lost weight during the 30 days after translocation or became heavier than animals at the donor site. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F861https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F861Fri, 06 Sep 2013 14:31:31 +0100Collected Evidence: Collected Evidence: Use prescribed fire or modifications to burning regime in grassland Two studies (including one before-and-after, site comparison study) in the USA and Argentina found that annual prescribed fires in grassland decreased numbers of amphibian species and abundance or, along with changes in grazing regime, increased rates of species loss. One replicated, before-and-after study in the USA found that spring, but not autumn or winter burns, decreased salamander abundance. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F862https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F862Fri, 06 Sep 2013 15:42:39 +0100Collected Evidence: Collected Evidence: Create ponds for great crested newts Three before-and-after studies (including two replicated studies) in Germany and the UK found that naturally colonizing, captive-bred and translocated great crested newts established breeding populations at 57–75% of created ponds or sites. One systematic review in the UK found that there was no conclusive evidence that mitigation, which often included pond creation, resulted in self-sustaining populations. Three replicated, before-and-after studies in the UK found that up to 88% of created ponds were colonized by translocated or by small numbers of naturally colonizing great crested newts. One replicated before-and-after study in the UK found that head-started great crested newts reproduced in 38% of created ponds. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F863https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F863Fri, 06 Sep 2013 15:57:48 +0100Collected Evidence: Collected Evidence: Create ponds for green toads Two before-and-after studies (including one controlled study) in Denmark found that pond creation, along with other interventions, significantly increased green toad populations. One replicated, before-and-after study in Sweden found that green toads used 59% and reproduced in 41% of created ponds. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F864https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F864Fri, 06 Sep 2013 16:23:40 +0100Collected Evidence: Collected Evidence: Create ponds for frogs Three of five before-and-after studies (including one replicated study) in Australia, Spain, the UK and USA found that translocated, head-started, captive-bred and naturally colonizing frogs established breeding populations in created ponds. Two found that breeding populations were established at one of four sites by translocated frogs, but were not established by captive-bred frogs. One replicated, before-and-after study in Denmark found that frogs colonized created ponds. One before-and-after study in the Netherlands found that pond creation, along with vegetation clearance, increased a breeding population of European tree frogs. An additional three of four replicated, before-and-after studies in Italy, the UK and USA found that naturally colonizing frog species reproduced in 50–75% of created ponds. Two found that translocated frog species reproduced in only 31% of created ponds, or colonized but did not reproduce successfully. One replicated study in the USA found that survival of translocated Oregon spotted frogs increased with increasing age of created ponds. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F865https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F865Tue, 10 Sep 2013 14:47:43 +0100Collected Evidence: Collected Evidence: Create ponds for natterjack toads Five before-and-after studies (including three replicated and one controlled study) in the UK and Denmark found that pond creation, along with other interventions, significantly increased natterjack toad populations, or in two cases maintained or increased populations at 75% of sites. One replicated, site comparison study in the UK found that compared to natural ponds, created ponds had lower natterjack toad tadpole mortality from desiccation, but higher mortality from predation by invertebrates. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F866https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F866Tue, 10 Sep 2013 15:47:29 +0100Collected Evidence: Collected Evidence: Create ponds for salamanders (including newts) Three before-and-after studies (including two replicated studies) in France, Germany and the USA found that naturally colonizing alpine newts, captive-bred smooth newts or translocated spotted salamanders established stable breeding populations in 20–100% of created ponds. Two replicated, before-and-after study in France and China found that alpine newts or Chinhai salamanders reproduced in 60–100% of created ponds. One small, replicated, before-and-after study in the USA found that translocated spotted salamanders but not tiger salamanders reproduced in created ponds. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F867https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F867Tue, 10 Sep 2013 15:55:04 +0100Collected Evidence: Collected Evidence: Create ponds for toads Four before-and-after studies (including one replicated study) in Germany, the UK and USA found that translocated and naturally colonizing toads established breeding populations in created ponds, or in one case 33% of created ponds. Two before-and-after studies (including one replicated study) in Denmark and Switzerland found that common toads and midwife toads naturally colonized 29–100% of created ponds, whereas captive-bred garlic toads did not colonize. One before-and-after study in Denmark found that creating and restoring ponds, along with head-starting, increased populations of European fire-bellied toads. One replicated, before-and-after study in Switzerland found that midwife toads reproduced in 16% of created ponds. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F868https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F868Wed, 11 Sep 2013 08:55:34 +0100Collected Evidence: Collected Evidence: Create ponds for amphibians Twenty-eight studies investigated the colonization of created ponds by amphibians in general (rather than by targeted species, which are discussed below). All of the studies found that amphibians used some or all created ponds. Nine site comparison studies (including seven replicated studies) in Australia, Canada, Spain, the UK and USA compared amphibian numbers in created and natural ponds. Five found that numbers of species or breeding species were similar or higher in created ponds, and numbers of ponds colonized were similar. Four found that species composition differed, and comparisons between abundance of individual species, juvenile productivity and size at metamorphosis differed depending on species. One found that numbers of species were similar or lower depending on the permanence of created water bodies. One found that populations in created ponds were less stable. One review and two replicated, before-and-after studies in Denmark and the USA found that amphibians established stable populations in 50–100% of created ponds. Six replicated studies (including one randomized study) in France, the Netherlands, UK and USA found that amphibians used 64–100% and reproduced in 64–68% of created ponds, or used 8–100% and reproduced in 2–62% depending on species. One review and 15 studies (including 12 replicated studies, one of which was randomized) in Europe and the USA found that created ponds were used or colonized by up to 15 naturally colonizing species, up to 10 species that reproduced, as well as by captive-bred amphibians. Five replicated studies (including three site comparison studies) in Denmark, Estonia, France, Italy and the USA found that pond creation, and restoration in three cases, maintained and increased amphibian populations or increased numbers of species. Seven studies (including one review) in Austria, Denmark, Poland, the Netherlands and USA found that use or colonization of or reproductive success in created ponds was affected by pond age, permanence, vegetation cover, surrounding landscape, distance to existing ponds and presence of fish. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F869https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F869Wed, 11 Sep 2013 09:16:41 +0100Collected Evidence: Collected Evidence: Release captive-bred frogs Four of five studies (including one replicated study and one review) in Europe, Hong Kong and the USA found that captive-bred frogs released as tadpoles, juveniles or adults established populations or stable breeding populations at 88-100% of sites, and in some cases colonized new sites. One study found that stable breeding populations were not established. One before-and-after study in Spain found that released captive-bred, captive-reared and translocated frogs established breeding populations at 79% of sites. Three replicated studies in Australia and the USA found that a high proportion of captive-bred frogs released as eggs survived to metamorphosis, some released as tadpoles survived at least the first few months or few released as froglets survived. Three studies (including two replicated studies) in Australia, Italy and the UK and a review in the USA found that captive-bred frogs reproduced at all or 31–33% of release sites, or that there was very limited breeding by released frogs. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F870https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F870Wed, 11 Sep 2013 14:52:42 +0100Collected Evidence: Collected Evidence: Release captive-bred amphibians One review found that 41% of release programmes of captive-bred or head-started amphibians showed evidence of breeding in the wild for multiple generations, 29% showed some evidence of breeding and 12% evidence of survival following release. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F871https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F871Wed, 11 Sep 2013 15:54:35 +0100Collected Evidence: Collected Evidence: Release captive-bred green and golden bell frogs One review and two before-and-after studies in Australia found that captive-bred green and golden bell frogs released mainly as tadpoles did not established breeding populations, or only established stable breeding populations following one of four release programmes. One study in Australia found that a small proportion of captive-bred green and golden bell frog released as tadpoles survived at least 13 months after release. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F872https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F872Wed, 11 Sep 2013 16:03:45 +0100Collected Evidence: Collected Evidence: Release captive-bred Mallorcan midwife toads Three studies (including one replicated study and one review) in Mallorca found that captive-bred midwife toads released as tadpoles, toadlets or adults established breeding populations at 38%, 80% or 100% of sites. One randomized, replicated, controlled study in the UK found that predator defences were maintained, but genetic diversity reduced in a captive-bred reintroduced population. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F873https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F873Thu, 12 Sep 2013 10:43:06 +0100Collected Evidence: Collected Evidence: Release captive-bred salamanders (including newts) One before-and-after study in Germany found that captive-bred great crested newts and smooth newts released as larvae, juveniles and adults established stable breeding populations. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F874https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F874Thu, 12 Sep 2013 10:48:40 +0100Collected Evidence: Collected Evidence: Release captive-bred toads Two of three studies (including two replicated studies) in Denmark, Sweden and the USA found that captive-bred toads released as tadpoles, juveniles or metamorphs established populations, in one case at 70% of sites. One of the studies found that populations were not established from captive-bred and head-started toads. Two studies in Puerto Rico found that survival of released captive-bred Puerto Rican crested toads was low and that 25% were predated within two days of release. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F875https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F875Thu, 12 Sep 2013 10:51:57 +0100Collected Evidence: Collected Evidence: Freeze sperm or eggs for future use Nine replicated studies (including three controlled studies) in Austria, Australia, Russia, the UK and USA found that following freezing frog and toad sperm viability depended on species and/or cryoprotectant used. One found that although sperm viability was low following freezing, it could be frozen for up to 58 weeks. Five of the studies and one additional replicated study in Australia found that following freezing, viability of sperm and in one case eggs, also depended on storage temperature, storage method, freezing or thawing rate. Seven replicated studies (including three controlled studies) in Austria, Australia, the UK and USA found that frog and toad sperm viability was greatest following freezing with the cryoprotectant dimethyl sulfoxide, glycerol, sucrose or dimethyl formamide. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F876https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F876Thu, 12 Sep 2013 11:09:04 +0100Collected Evidence: Collected Evidence: Use prescribed fire or modifications to burning regime in forests Eight of 14 studies (including three randomized, replicated, controlled studies) in Australia, North America and the USA found no effect of prescribed forest fires on amphibian abundance or numbers of species. Four found that forest fires had mixed effects on amphibian abundance depending on species, species and year or season of burn. Three found that fires increased amphibian abundance or numbers of species. One found that abundance decreased with fires. Two studies (including one randomized, replicated, controlled study) in the USA found that numbers of amphibian species and abundance increased or abundance decreased with time since prescribed forest fires. One before-and-after study in the USA found that spotted salamander hatching success increased following a prescribed forest fire. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F877https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F877Thu, 12 Sep 2013 12:56:53 +0100Collected Evidence: Collected Evidence: Restore ponds Fifteen studies investigated the effectiveness of pond restoration for amphibians. One replicated, before-and-after study in Denmark found that pond restoration had mixed effects on European tree frog population numbers depending on site. One replicated, controlled, before-and-after study in the UK found that pond restoration did not increase great crested newt populations. Six replicated, before-and-after studies (including one controlled and one site comparison study) in Denmark, Estonia, Italy and the UK found that pond restoration and creation increased numbers of amphibian species, maintained or increased populations, or increased pond occupancy and ponds with breeding success. One found that numbers of species did not increase. Two before-and-after studies (including one replicated study) in Estonia found that pond restoration, along with terrestrial habitat management, maintained or increased populations of natterjack toads. One systematic review in the UK found that there was no conclusive evidence that mitigation, which often included pond restoration, resulted in self-sustaining great crested newt populations. One small, replicated study in the USA found that pond restoration had mixed effects on spotted salamander hatching success depending on restoration method. One replicated, before-and-after study in the UK found that restoration increased the number of ponds used by breeding natterjack toads. One replicated study in Sweden found that following restoration green toads only reproduced in one of 10 ponds. Three before-and-after studies (including one replicated, controlled study) in Denmark and Italy found that restored and created ponds were colonized by 1–7 species, with 6–65% of ponds colonized and 35% used for breeding. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F878https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F878Thu, 12 Sep 2013 15:17:02 +0100Collected Evidence: Collected Evidence: Restore wetland Seventeen studies investigated the effectiveness of wetland restoration for amphibians. Ten site comparison studies (including eight replicated studies) in Canada and the USA compared amphibian numbers in restored and natural wetlands. Eight found that amphibian abundance, numbers of species and species composition were similar. Two found that the number of species or abundance was lower and species composition different in restored wetlands. One found that restored wetlands were used more or less depending on the habitat surrounding natural wetlands. One global review found that in 89% of cases, restored and created wetlands had similar or higher amphibian abundance or numbers of species to natural wetlands. Seven of nine studies (including six site comparison and/or replicated studies) in Canada, Taiwan and the USA found that wetland restoration increased numbers of amphibian species, with breeding populations establishing in some cases. Three found that numbers of species or abundance did not increase with restoration. Two found mixed effects, with restoration maintaining or increasing abundance of individual species. Three replicated studies (including two site comparison studies) in the USA found that numbers of species in restored wetlands were affected by wetland size, proximity to source ponds and seasonality, but not wetland age. Three studies (including two replicated, site comparison studies) in Taiwan and the USA found that restored wetlands were colonized by three to eight amphibian species. One before-and-after study in the USA found that three target species did not recolonize restored wetlands. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F879https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F879Thu, 12 Sep 2013 15:34:57 +0100Collected Evidence: Collected Evidence: Create wetland Fifteen studies investigated the effectiveness of creating wetlands for amphibians. Five site comparison studies (including four replicated studies) in the USA compared created to natural wetlands and found that created wetlands had similar numbers of amphibian species, amphibian abundance or communities depending on depth as natural wetlands. Two of the studies found that created wetlands had fewer amphibian species or lower abundance and different communities compared to natural wetlands. One site comparison study in the USA found that created wetlands had similar numbers of species to adjacent forest. One global review and two site comparison studies (including one replicated study) in the USA combined created and restored wetlands and compared them to natural wetlands and found that numbers of amphibian species and abundance was higher or similar, or higher in 54% of studies and similar in 35% of studies reviewed compared to natural wetlands. Three site comparison studies (including one replicated study) in the USA found that certain amphibian species were only found in created or natural wetlands. One before-and-after study in Australia found that captive-bred green and golden bell frog tadpoles released into a created wetland did not establish a self-sustaining population. Five studies (including two replicated studies) in Kenya and the USA that investigated colonization of created wetlands found that four to 15 amphibian species used or colonized the wetlands. One global review and three studies (including two replicated studies) in the USA found that numbers of amphibian species and amphibian abundance in created wetlands were affected by wetland design, vegetation, water levels, surrounding habitat, fish presence and distance to source wetlands. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F880https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F880Fri, 13 Sep 2013 11:16:59 +0100