Collected Evidence: Collected Evidence: Legally protect habitats Four studies (two replicated) from Europe found population increases following habitat protection, more positive population trends in protected habitats, compared with outside, or with increases amounts of protected habitats. A literature review reported that a large number of cranes (Gruidae) of seven species used nature reserves in China, whilst a replicated, randomised and controlled study from Argentina found that some guilds of birds were found at higher species richnesses in protected forests, some at higher densities, and that some showed no differences. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F158https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F158Tue, 15 May 2012 13:48:22 +0100Collected Evidence: Collected Evidence: Pay farmers to cover the costs of bird conservation measures Three reviews from the UK of three studies captured reported population increases of three species after the introduction of specially-designed agri-environment schemes. These species were cirl buntings, corncrakes and Eurasian thick-knees. One of these found that many other species continued to decline. Twenty-two of 25 studies all from Europe, including a systematic review,  examining local population levels or densities found that at least some birds studied were at higher densities, had higher population levels or more positive population trends on sites with agri-environment schemes, compared to non-agri-environment scheme sites. Some studies found that differences were present in all seasons, others in either summer or winter. Fifteen studies from Europe, including a systematic review, found that some or all species were not found at higher densities, had similar or lower population levels, showed similar population trends on sites with agri-environment schemes, compared with non-agri-environment scheme sites, or showed negative population trends. A study from the Netherlands found that many agri-environment scheme farms were sited in areas where they were unlikely to be effective. One small study from the UK found no differences between winter densities of seed-eating birds on UK Higher Levels Stewardship sites, compared with those under Entry Level Stewardship. A replicated study from the UK found that grey partridge survival was higher on agri-environment scheme sites than non-scheme sites. This difference was not significant every year. Two of three studies investigating reproductive productivity, including one replicated study, found that productivity was higher on farms under agri-environment schemes. One replicated study from the UK found no effect of agri-environment schemes on productivity. A review (Vickery et al. 2010) found that the amount of land entering an agri-environment scheme was on target, but that some options were not being used at high enough rates to help many species. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F172https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F172Sun, 20 May 2012 14:06:41 +0100Collected Evidence: Collected Evidence: Maintain traditional water meadows A replicated study from the UK found that northern lapwing and common redshank populations increased on nature reserves managed to maintain water meadows. Two replicated studies from the Netherlands found that there were more waders or birds overall on specially managed meadows or 12.5 ha plots including several management interventions than on conventional fields, but one study found that these differences were present before the management scheme was introduced and the other found no differences between individual fields under different management. A replicated study from the UK found that common snipe decreased on nature reserves managed to maintain water meadows and a replicated before-and-after study from the Netherlands found that wader population trends on specially managed meadows were no different to those on conventionally-managed meadows. A replicated study from the UK found that lapwing populations on three of four water meadow sites managed for conservation did not have high enough productivity to maintain population levels. All three sites were judged deficient in at least one management category.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F229https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F229Tue, 17 Jul 2012 15:37:55 +0100Collected Evidence: Collected Evidence: Use legislative regulation to protect wild populations Six out of seven before-and-after studies and two literature reviews/meta-analyses found evidence that legislation protects bird populations. Five studies in Europe, Indonesia and across the world found increased population levels of vultures, raptors, cranes and cockatoos following protective legislation (amongst other interventions). However, one found populations of raptors declined soon after. The literature review also found two cases of limited or no impact of legislation. Two before-and-after studies from Denmark and the USA and Canada and the meta-analysis found increased estimated survival of falcons, ducks and parrots with stricter protection, but not necessarily population-level responses. A meta-analysis found decreased harvest of parrots in areas with stricter protection regimes, but a before-and-after study found no evidence for reduced shearwater harvest with legislation.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F271https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F271Thu, 19 Jul 2012 16:57:57 +0100Collected Evidence: Collected Evidence: Use education programmes and local engagement to help reduce persecution or exploitation of species Five out of six studies from across the world found increases in bird populations or decreases in mortality following education programmes. In all but one case, education was one of several interventions employed. A replicated before-and-after study from Canada also found that there was a significant shift in local peoples’ attitudes to conservation and exploited species following educational programmes. One study from Venezuela found no evidence for decreases in yellow-shouldered parrot Amazona barbadensis poaching following an educational programme in local schools. The authors argue that the benefits would probably be seen later in the project.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F274https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F274Thu, 19 Jul 2012 18:28:35 +0100Collected Evidence: Collected Evidence: Legal protection of species Three reviews (including one systematic review) in the Netherlands and UK (Bosman et al. 2011, Spitzen-van der Sluijs et al. 2011, Lewis 2012) found that legal protection of amphibian species was not effective at protecting populations during development. Two reviews in the UK (Edgar et al. 2005, Lewis 2012) found that the number of great crested newt mitigation licences issued over 10 years increased to over 600 in England and Wales.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F779https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F779Thu, 22 Aug 2013 11:46:02 +0100Collected Evidence: Collected Evidence: Implement legal protection for primate species under threat A before-and-after study in India found that following a ban on export of the species, a population of rhesus macaques increased over 17 years. Two studies in Thailand and India found that primate populations declined despite the respective species being legally protected, alongside other interventions. One before-and-after study in Malaysia found that the majority of introduced Müller's Bornean gibbons died despite legal protection, along with other interventions. A site comparison of five sites in Cameroon found that drill populations declined in four sites but increased at one, despite legal protection. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1524https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1524Thu, 19 Oct 2017 09:39:16 +0100Collected Evidence: Collected Evidence: Legally protect primate habitat A review on the status of rhesus monkeys and grey snub-monkeys in China found that primate numbers increased or no more individuals were killed after the area was legally protected, alongside other interventions. One before-and-after study in Kenya found that Tana River red colobus monkey and crested mangabey numbers decreased despite the area being declared legally protected, alongside other interventions. One before-and-after study in China found that Hainan gibbon numbers increased by 34% over nine years after the area was declared legally protected. One before-and-after study in Brazil found that most golden lion tamarins did not survive over seven years despite being reintroduced to a legally protected area, alongside other interventions yet they reproduced and surviving offspring partly compensated adult mortality. Two before-and-after studies in the Republic of Congo and Gabon found that most central chimpanzees and lowland gorillas reintroduced to areas that received legal protection, alongside other interventions, survived over 4–5 years. One controlled, site comparison study in Mexico found that black howler monkeys in protected areas had lower stress levels than individuals living in unprotected forest fragments. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1578https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1578Fri, 20 Oct 2017 12:49:30 +0100Collected Evidence: Collected Evidence: Legally protect peatlands Five studies evaluated the effects on peatland habitats of legally protecting them: two of tropical peat swamp forest, two of unspecified peatlands and one of a bog. Peatland habitat (3 studies): Two studies in Indonesia reported that peat swamp forest was lost from within the boundaries of national parks. However, one of these studies was a site comparison and reported that forest loss was greater outside the national park. One before-and-after study of peatlands in China reported that peatland area initially decreased, but then increased, following legal protection. Plant community composition (1 study): One before-and-after study in a bog in Denmark reported that the plant community compositon changed over 161 years of protection. In particular, woody plants became more abundant. Vegetation cover (1 study): One site comparison study in a peatland in Chile found that a protected area had greater vegetation cover (total, herbs and shrubs) than an adjacent grazed and moss-harvested area. Overall plant richness/diversity (2 studies): One before-and-after study in Denmark reported that the number of plant species in a protected bog fluctuated over time, with no clear trend. One site comparison study in a peatland in Chile found that a protected area had lower plant richness and diversity (but also fewer non-native species) than an adjacent grazed and harvested area. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1796https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1796Tue, 28 Nov 2017 08:26:41 +0000Collected Evidence: Collected Evidence: Legally protect bats during development Four studies evaluated the effects of legally protecting bats by issuing licences during development on bat populations. The four studies were in the UK. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (2 STUDIES) Change in human behaviour (2 studies): One review in the UK found that the number of development licences for bats more than doubled over three years in Scotland. One review in the UK found that 81% of licensees did not carry out post-development monitoring to assess whether bats used the roost structures installed. OTHER (3 STUDIES) Impact on bat roost sites (3 studies): One review in the UK found that licenced activities during building developments had a negative impact on bat roosts, with 68% of roosts being destroyed. One replicated, before-and-after study in the UK found that five of 28 compensation roosts provided under licence were used, and two by similar or greater numbers of bats after development. One review in the UK found that 31–67% of compensation roosts provided under licence were used by bats. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1935https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1935Fri, 30 Nov 2018 14:50:33 +0000Collected Evidence: Collected Evidence: Legally protect bat habitats Five studies evaluated the effects of legally protecting bat habitats on bat populations. Four studies were in Europe and one was in India. COMMUNITY RESPONSE (2 STUDIES) Community composition (1 study): One replicated, site comparison study in India found that the composition of bat species was similar in protected forest and unprotected forest fragments. Richness/diversity (2 studies): Two replicated, site comparison or paired sites studies in Europe and India found that the number of bat species did not differ between protected and unprotected forests or forest fragments. One replicated, site comparison study in France found that protected sites had a greater number of bat species than unprotected sites. POPULATION RESPONSE (4 STUDIES) Abundance (4 studies): One replicated, site comparison study in the UK found that the activity (relative abundance) of Daubenton’s bats was higher over rivers on farms in protected areas than in unprotected areas. One replicated, paired sites study in Europe found that the activity of common noctule bats was higher in protected forests than unprotected forests, but bat activity overall did not differ. Two replicated, site comparison studies in France and India found higher overall bat activity, higher activity of three of six bat species/species groups and a greater number of bats in protected sites and forests than unprotected sites and forests. BEHAVIOUR (1 STUDY)         Use (1 study): One study in Spain found that the distributions of 10 of 11 bat species overlapped with areas designated to protect them significantly more than by chance. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2045https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2045Thu, 06 Dec 2018 15:34:12 +0000Collected Evidence: Collected Evidence: Legally protect habitat for mammals Seven studies evaluated the effects of legally protecting habitat for mammals. One study each was in Zambia, the USA, Tanzania, Brazil, Nepal and India and one was a systematic review of sites with a wide geographic spread. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (7 STUDIES) Abundance (7 studies): A systematic review of protected areas across the globe found that 24 of 31 studies reported an increase in mammal populations in protected areas relative to unprotected areas. Three studies (including two site comparison studies), in Zambia, the USA and Nepal, found that populations of red lechwe, black bears and one-horned rhinoceros grew following site protection or were higher than in adjacent non-protected sites. One of three site comparison studies, in Tanzania, Brazil and India, found that populations of more mammal species increased inside protected areas than in adjacent unprotected areas. One study found that populations of only three of 11 species were higher on protected than on unprotected land whilst the third study found that 13 of 16 species were less abundant in a protected area than in a nearby unprotected area. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2559https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2559Tue, 09 Jun 2020 11:56:39 +0100Collected Evidence: Collected Evidence: Prohibit or restrict hunting of a species Five studies evaluated the effects of prohibiting or restricting hunting of a mammal species. One study each was in Norway, the USA, South Africa, Poland and Zimbabwe. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (5 STUDIES) Abundance (2 studies): Two studies (including one before-and-after study), in the USA and Poland, found that prohibiting hunting led to population increases of tule elk and wolves. Survival (3 studies): A before-and-after study in Norway found that restricting or prohibiting hunting did not alter the number of brown bears killed. A study in Zimbabwe reported that banning the hunting, possession and trade of Temminck’s ground pangolins did not eliminate hunting of the species. A before-and-after study in South Africa found that increasing legal protection of leopards, along with reducing human-leopard conflict by promoting improved animal husbandry, was associated with increased survival. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2597https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2597Thu, 11 Jun 2020 15:05:02 +0100Collected Evidence: Collected Evidence: Cease or prohibit all types of fishing in a marine protected area Seventy-nine studies examined the effects of ceasing or prohibiting all types of fishing in a marine protected area on fish populations. Fifteen studies were in the Indian Ocean (Kenya, Tanzania, South Africa, Mozambique, Madagascar, multiple African countries, Australia). Twelve studies were in the Mediterranean Sea (Spain, France, Italy). Ten studies were in the Pacific Ocean (New Zealand, USA, Hawaii, New Caledonia, Costa Rica, Tonga, Vanuatu, Solomon Islands). Seven studies were in each of the Coral Sea (Australia, Vanuatu), the Tasman Sea (New Zealand, Australia) and the Atlantic Ocean (Brazil, USA, Puerto Rico, Argentina, South Africa, UK, Canary Islands, Portugal, Turks and Caicos Islands). Four studies were in the Philippine Sea (Philippines). Three studies were in the Caribbean Sea (Belize, Puerto Rico). One study was in each of the Gulf of Mexico (USA), the Java Sea (Indonesia), the Pacific and Indian Oceans (multiple countries), the Sulu Sea (Malaysia) and the North Sea (Norway). Six studies were reviews of marine reserves (New Zealand, Latin America/Caribbean, regions unspecified and across the world).  COMMUNITY RESPONSE (26 STUDIES)  Community composition (7 studies): Seven site comparison studies (two replicated, and one before-and-after) in the Mediterranean Sea, Indian Ocean, Philippine Sea and the Atlantic Ocean found that protected areas where all fishing had been prohibited for between three and 16 years, had a different fish community composition, compared to fished areas.  Richness/diversity (22 studies): Fourteen of 20 site comparison studies (eight replicated, one replicated and paired, and one before-and-after) in the Indian Ocean, Mediterranean Sea, Philippine Sea, Tasman Sea, Atlantic Ocean, Caribbean Sea, Coral Sea and the Pacific Ocean, found that marine protected areas that had prohibited all fishing for between one to more than 25 years, had higher fish species/richness compared to fished areas. Six studies found similar fish species/richness between one and 20 years after all fishing was banned in protected areas, compared to fished areas. One systematic review in the Atlantic and Pacific Oceans found no difference in species richness between unfished protected areas and fished areas. One replicated, site comparison study in the Indian Ocean found that the effects of prohibiting all fishing on fish species richness/diversity after 15 years varied with the sampling method used. POPULATION RESPONSE (66 STUDIES) Abundance (64 studies): Thirty of 54 site comparison studies (18 replicated, eight replicated and paired, two before-and-after, one paired and before-and-after, and one replicated and before-and-after) in the Indian Ocean, Atlantic Ocean, Mediterranean Sea, Pacific Ocean, Tasman Sea, Coral Sea, Philippine Sea, Caribbean Sea, Gulf of Mexico, and the Sulu Sea, found that marine protected areas that had been prohibiting all fishing for up to 25 years or more, had higher abundances (density and/or biomass) of all fish (total fish biomass, total fish density), fishery targeted fish species, non-fishery targeted fish species and all or most of the individual fish species/groups monitored, except fish densities (all or most) and non-fishery targeted species, compared to unprotected fished areas and/or partly-fished protected areas. The studies also found that in some cases where the total fish biomass or densities were higher in no-fished areas, the effect varied between individual groups of fish based on species family and/or position in the food chain, commercial target and non-target species, fish sizes, depth and habitat types. Eight studies found that inside protected areas prohibiting all fishing there were similar abundances of all fish, and all or most of the individual fish species/groups monitored, compared to fished areas between one and 20 years after implementation. The other sixteen studies found that the effect of prohibiting fishing in protected areas for three to 20 years on fish abundance varied between fish species or groups and on their fished status (fishery target or non-target) and/or position in the food chain. One also found that the effect varied with size or age of the protected areas. Five of six reviews (three systematic) across the world, in the Pacific and/or Atlantic Oceans and in unreported regions found that non-fished marine reserves with one to 27 years of protection had higher abundances of all fish, all fish and invertebrates combined and blue cod compared to fished areas, but there were differences between species/groups and fishing intensity outside reserves. The other review found that fish abundance varied between species in no-take marine reserves between one and 25 years old, and was affected by food chain position, level of exploitation and duration of protection. One replicated study in the Pacific Ocean found a long-term decline in the abundance/presence of eight of 12 shark and ray species inside an established (>15 years) no-fishing protected area, however enforcement was poor. One before-and after, site comparison study in the Pacific Ocean, found no differences in overall fish abundance between a marine reserve closed permanently to fishing for five years and a closed area that was harvested for two years during the same period. One site comparison study in the Coral Sea found that in a no-take zone of an area protected for at least 10 years, fish abundance of four of six fish groups were similar to no-entry and fished zones, but two had lower abundance than the no-entry zone. One replicated, paired, site comparison study in the Tasman Sea found that in a non-fished marine park zone abundance of commercially targeted fish was higher than partly fished zones but lower than unprotected areas after four to eight years. Reproductive success (1 study): One site comparison study in the Mediterranean Sea found more eggs of four commercially targeted fish species inside a non-fished marine reserve enforced for three years than in fished areas outside the reserve. Survival (1 study): One site comparison study in the Atlantic Ocean found that prohibiting all fishing in a marine protected area for three years resulted in similar survival of red hind grouper, compared to fished areas. Condition (20 studies): Two global review studies (one systematic) and two systematic reviews in the Pacific Ocean and the Atlantic and Pacific Oceans found that prohibiting all fishing in marine protected areas for one to 27 years resulted in larger fish overall and larger blue cod compared to fished areas, but there were differences between individual fish families or species. Eight of 11 site comparison studies (four replicated, one before-and-after, one paired, and one replicated and paired) in the Tasman Sea, Pacific Ocean, Indian Ocean, Mediterranean Sea, Atlantic Ocean, Java Sea and the Philippine Sea, found that non-fished protected areas had larger fish overall and larger individuals of all or most of the fish species/groups monitored, compared to fished areas, after one to 22 years. The other three studies found similar fish sizes of all or all but one species, compared to fished areas one to 16 years after all fishing was prohibited. Three site comparison studies (one replicated) in the Coral Sea, Caribbean Sea and the Atlantic Ocean found that fish size in protected areas that had not been fished for six to more than 20 years, varied between fish species or food chain groups. One site comparison study in the Atlantic Ocean found that red hind grouper were larger, but had similar growth, in an area protected from fishing for three years compared to fished areas. One site comparison study in the Atlantic Ocean found that young lemon sharks in areas protected from fishing for 20 years had similar growth rates, but lower condition, than sharks in unprotected fished areas. BEHAVIOUR (2 STUDIES)  Behaviour change (2 studies): One replicated, site comparison study in the Pacific and Indian Oceans found that surgeonfish and parrotfish inside established protected areas where fishing was prohibited, showed a similar avoidance response to fishing gears as in fished areas, and this increased with increasing fishing intensity outside the protected areas. One replicated, site comparison study in the Indian Ocean found that in non-fished areas protected for one and 24 years, fish grazing rates were higher compared to fished areas.  OTHER (15 STUDIES) Use (7 studies): Four of six site comparison studies in the Pacific Ocean, Atlantic Ocean and the Tasman Sea found that marine protected areas where all fishing had been prohibited for at least five to 15 years, were used for a large proportion of time by shark and ray species and commercially important reef fish species, compared to fished areas, thus were provided protection from fishing. Two other studies found that time spent inside areas closed to all fishing for 20 years and over 30 years, varied between species and with size for three shark species and with size for giant trevally. One replicated study in the Indian Ocean found that most individuals of five fish species remained inside a marine reserve zone closed to fishing over a nine-year period. Catch abundance (2 studies): One of two site comparison studies in the Mediterranean Sea and Pacific Ocean found that commercial fish catch rates in small-scale traditional fisheries were highest closest to a marine reserve closed to all fishing for 22 years, and decreased with increasing distance from the reserve. The other study found that there was no increase in fish catch rates in commercially landed catch in the five years after a no-fishing zone was implemented in a co-managed protected area. Stock biomass (1 study): One replicated, site comparison study in the Indian Ocean found that the stock biomass (the harvested portion of the population) of reef fish species was highest in enforced protected areas closed to all fishing, compared to various other area management regimes.  Fishing mortality (2 studies): Two site comparison studies in the North Sea and Pacific Ocean found that prohibiting fishing in protected areas resulted in reduced commercial fishing mortality of corkwing wrasse tagged inside non-fished marine reserves compared to fished areas, and that the overall fishing mortality of grey reef sharks tagged inside protected areas was low.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2682https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2682Sat, 28 Nov 2020 14:35:06 +0000Collected Evidence: Collected Evidence: Prohibit or restrict hunting of marine and freshwater mammal species Five studies evaluated the effects of prohibiting hunting of marine mammal species. One study was in each of the Kattegat and Skagerrak seas (Denmark and Sweden), the North Atlantic Ocean, North Pacific Ocean and the Southern Hemisphere, the South Pacific Ocean (Australia), the North Atlantic Ocean (Greenland) and the Southern Ocean (Australia). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (5 STUDIES) Abundance (5 studies): Four of five studies (including three before-and-after studies) in the Kattegat and Skagerrak Seas, the South Pacific Ocean, the North Atlantic Ocean and the Southern Ocean found that after hunting was prohibited, the abundance of harbour seals and humpback whales increased over 7–30 years. The other study found that numbers of mature male sperm whales did not differ significantly before or 31 years after hunting was prohibited. One review in the North Atlantic Ocean, North Pacific Ocean and the Southern Hemisphere found significant increase rates for 10 of 12 baleen whale populations during 7–21 years after legislation to prohibit hunting was introduced. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2780https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2780Thu, 04 Feb 2021 16:09:52 +0000Collected Evidence: Collected Evidence: Legally protect habitat for marine and freshwater mammals Four studies evaluated the effects of legally protecting habitat for marine and freshwater mammals. One study was in each of the North Atlantic Ocean (Portugal), the South Pacific Ocean (New Zealand), the North Sea (UK) and the Port River estuary (Australia). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (4 STUDIES) Abundance (2 studies): One before-and-after study in the North Atlantic Ocean found that a population of Mediterranean monk seals increased during eight years after the islands they inhabited were legally protected. One before-and-after study in the North Sea found that a population of bottlenose dolphins was estimated to be a similar size before and after part of its range was protected. Survival (2 studies): One before-and-after study in the South Pacific Ocean found that the survival rate of Hector’s dolphins was higher after a coastal area was legally protected than before. One before-and-after study in the Port River estuary found that after the area became legally protected a similar number of Indo-Pacific bottlenose dolphin strandings were recorded compared to before protection, but the number of strandings caused by humans decreased. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2915https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2915Mon, 08 Feb 2021 16:29:11 +0000Collected Evidence: Collected Evidence: Exclude or remove livestock from historically grazed brackish/salt marshes Fifteen studies evaluated the effects, on vegetation, of excluding or removing livestock from historically grazed brackish/salt marshes. There were five studies in Germany. There were two studies in the UK, Denmark and the Netherlands. There was one study in each of the USA, Sweden, France and Argentina. Livestock were sheep, cattle, sheep and cattle, cattle and horses, or unspecified. There was overlap in the sites used in two studies. Two other studies took place in one marsh, but with different experimental set-ups. VEGETATION COMMUNITY Overall extent (1 study): One controlled study of a salt marsh in Germany reported that in a plot fenced to exclude cattle for eight years, the total vegetated area was greater than in a plot that remained grazed. Community types (1 study): One site comparison study of brackish and salt marshes in Germany reported that reducing (or stopping) grazing affected the nature of transitions between vegetation types over time, but that the precise effect varied with environmental conditions. Community composition (5 studies): Three paired studies (two also replicated and controlled) in brackish/salt marshes in France, Argentina and the Netherlands reported that the effect of excluding livestock for 5–30 years on the overall plant community composition depended on plot elevation/flooding regime. In one of these studies, the effect of livestock exclusion was not separated from the effect of general legal protection. Two studies in one salt marsh in Denmark reported that excluding livestock had little effect on the identity of plant species in the community after six years. Overall richness/diversity (6 studies): Two studies (one controlled, one before-and-after) in one salt marsh in Denmark reported that excluding sheep and cattle for 6–7 years had no effect on overall plant species richness. One replicated, paired, controlled study in a salt marsh in the Netherlands reported that plots fenced to exclude cattle for seven years had lower plant species richness than areas that remained grazed. Two controlled studies (one also replicated and paired) in salt marshes in Germany found that the effect of removing sheep on overall plant species richness depended on the scale of measurement and the grazing intensity used for comparison – with inconsistent results across these studies even for similar scales and intensities. One paired, site comparison study of salt marshes in Argentina found that the effect of excluding cattle (along with legal protection) increased plant species richness at lower elevations, but did not significantly affect plant diversity at any elevation. VEGETATION ABUNDANCE Overall abundance (4 studies): Three studies (two controlled, one before-and-after) in salt marshes in the UK and Denmark reported that excluding livestock for 2–6 years maintained or increased overall vegetation abundance (although in one study, only by a small amount). One controlled study in a salt marsh in Germany found that a paddock left ungrazed for 16–18 years had greater overall vegetation cover than lightly or heavily grazed paddocks, but lower cover than a moderately grazed paddock. Individual species abundance (11 studies): Eleven studies quantified the effect of this action on the abundance of individual plant species. For example, five studies (four controlled, one before-and-after) on salt marshes in the UK, Denmark, Germany and the Netherlands reported that excluding livestock for 2–8 years reduced (or prevented increases in) cover of saltmarsh grass Puccinellia maritima. However, two controlled studies (one also replicated and paired) on salt marshes in Denmark and Sweden reported greater saltmarsh grass cover in areas fenced to exclude livestock for 1–6 years than in areas that remained grazed. Four studies (three controlled, one before-and-after) on salt marshes in Denmark and Germany reported that excluding or removing livestock for 4–16 years increased cover of sea purslane Halimione portulacoides. VEGETATION STRUCTURE Height (5 studies): Five controlled studies (two also replicated and paired) in salt marshes in Sweden and Germany, and brackish wet grassland in the UK, found that ungrazed plots (livestock excluded or removed) contained taller vegetation than plots that remained grazed. Vegetation was surveyed after one month, 1–8 years or 16–22 years. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2967https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2967Thu, 25 Mar 2021 14:15:09 +0000Collected Evidence: Collected Evidence: Reduce intensity of livestock grazing: brackish/salt marshes Nine studies evaluated the effects, on vegetation, of reducing livestock grazing intensity in brackish/salt marshes (without stopping grazing entirely). Five studies were in Germany. Four studies were in the Netherlands. Livestock were cattle, sheep or horses. There was overlap in the sites used in two of the German studies and three of the Dutch studies. VEGETATION COMMUNITY Overall extent (1 study): One controlled study of a salt marsh in Germany reported that the total vegetated area was slightly larger in plots grazed at a lower intensity, for eight years, than plots grazed at a higher intensity. Community types (4 studies): Two controlled studies of salt marshes in Germany and the Netherlands reported similar coverage, or similar change in coverage, of plant community types under different grazing intensities. Two studies of brackish and salt marshes in the Netherlands and Germany reported that reducing grazing intensity (along with other interventions) affected coverage of plant community types. In one study, the precise effect varied with environmental conditions. Community composition (1 study): One replicated, randomized, paired, before-and-after study on a salt marsh in the Netherlands found that plots grazed under different grazing intensities experienced a similar turnover of plant species over six years, and had a similar overall plant community composition after six years. Overall richness/diversity (5 studies): Three replicated, paired, controlled studies on salt marshes in Germany and the Netherlands found that plots grazed at lower intensities never had greater plant species richness, after 1–22 years, than plots grazed at higher intensities. One controlled study on a salt marsh in Germany found that paddocks grazed at low intensity had greater plant species richness, after 16–18 years, than paddocks grazed at higher intensities. Two studies of salt marshes in the Netherlands found that plant species richness increased over 6–14 years of reduced grazing intensity (sometimes along with other interventions). VEGETATION ABUNDANCE Overall abundance (1 study): One controlled study on a salt marsh in Germany reported that overall vegetation cover was greater in lightly and moderately grazed paddocks than in a heavily grazed paddock – with the highest cover of all in the moderately grazed paddock. Individual species abundance (6 studies): Six studies quantified the effect of this action on the abundance of individual plant species. For example, three studies (including two controlled) on salt marshes in Germany and the Netherlands reported that plots under different grazing intensities supported a similar abundance (frequency or cover) of saltmarsh grass Puccinellia maritima – but with a tendency for greater abundance under lower intensities. VEGETATION STRUCTURE Height (6 studies): Six controlled studies (three also replicated and paired) in salt marshes in Germany and the Netherlands reported that vegetation was taller on average (or contained taller vegetation patches) in areas that had been grazed at lower intensities. However, in one of the studies, this was only true for canopy height: understory grasses were a similar height under all grazing intensities. One of the replicated, paired, controlled studies found that, after two summers, variation in vegetation height between patches was similar under all grazing intensities. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2971https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2971Thu, 25 Mar 2021 14:16:01 +0000Collected Evidence: Collected Evidence: Use prescribed fire to maintain or restore disturbance: brackish/salt marshes Ten studies evaluated the effects, on vegetation, of using prescribed fire to maintain or restore disturbance in brackish/salt marshes. Seven studies were in the USA. Two studies were in Argentina but based on the same experimental set-up. One study was in Guadeloupe. VEGETATION COMMUNITY Community composition (1 study): One replicated, paired, controlled study in a salt marsh in Argentina reported that burned plots had a different overall plant community composition to unburned plots, five months after burning. The same was true in one of two comparisons 17 months after burning. Overall richness/diversity (5 studies): Three studies (including one replicated, paired, controlled) in brackish marshes in the USA and Guadeloupe reported that burning had no significant effect on overall plant species richness, measured approximately 10 weeks to 2 years after the latest burn. In one of the studies, the effects of burning and legal protection were not separated. One replicated, randomized, paired, controlled, before-and-after study in brackish marshes in the USA reported that burning typically had no significant effect on changes in plant species richness over two years. One replicated, paired, controlled study in a salt marsh in Argentina reported that burned plots had greater overall plant species richness and diversity than unburned plots, 5–17 months after burning. Characteristic plant richness/diversity (1 study): One study of a coastal marsh in the USA reported that over three years after restoration – involving a prescribed burn along with restoration of tidal exchange – the number of salt-tolerant plant species increased, whilst the number of freshwater plant species decreased. VEGETATION ABUNDANCE Overall abundance (5 studies): Three replicated studies (one also randomized, paired, controlled) in brackish marshes in the USA found that overall vegetation biomass was lower in burned than unburned plots, 10 weeks or 1 year after the latest burn. One replicated, randomized, paired, controlled, before-and-after study in alkali marshes in the USA found that a single prescribed burn had no significant effect on overall vegetation biomass: there was a similar change over two years in burned and unburned plots. One replicated, paired, controlled study in a salt marsh in Argentina found that the effect of a single prescribed burn on the frequency of seedlings depended on the time since burning, but that seedlings were more frequent in burned than unburned plots after 9–12 months. Characteristic plant abundance (1 study): One study of a coastal marsh in the USA found that over three years after restoration – involving a prescribed burn along with restoration of tidal exchange – the cover of salt-tolerant plant species increased, whilst the cover of freshwater plant species decreased. Individual species abundance (7 studies): Seven studies quantified the effect of this action on the abundance of individual plant species. For example, five studies quantified the effects of prescribed burning on the abundance of dominant cordgrasses Spartina sp. in brackish and salt marshes in the USA and Argentina. Two replicated, paired, controlled studies found that cordgrass abundance (biomass or cover) was lower in burned than unburned plots, between 10 weeks and 17 months after the latest burn. However, one replicated, paired, site comparison study found that burning typically had no significant effect on cordgrass biomass or density after 2–8 months. One replicated, before-and-after study found that cordgrass biomass was lower, but cover greater, one year after burning than before. One study reported mixed effects on cordgrass cover across two marshes. VEGETATION STRUCTURE Height (2 studies): Two studies (one controlled, one site comparison) in brackish marshes in the USA and Guadeloupe reported that the height of dominant grass-like plants was lower in burned than unburned areas for up to 1–2 years after the latest burn. The study in the USA reported recovery, to a slightly greater height than in unburned areas, after three years. The study in Guadeloupe also reported that the tallest trees in burned marshes were shorter than the tallest trees in unburned marshes. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3055https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3055Fri, 02 Apr 2021 08:57:38 +0100Collected Evidence: Collected Evidence: Engage local communities in conservation activities Six studies evaluated the effects on reptile populations of engaging local communities in reptile conservation. One study was in each of the Philippines, Mozambique, Brazil, Costa Rica, Australia and Colombia. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (5 STUDIES) Abundance (1 study): One site comparison study in Brazil found that areas where community-based management of fishing practices was implemented had a higher abundance of river turtles than areas with no community-based management. Reproductive success (3 studies): Two before-and-after studies (including one site comparison study) in Mozambique and Costa Rica found that after involving the community in monitoring of nesting activity, fewer sea turtle eggs were lost to poaching than before projects began. One replicated, before-and-after study in Australia found that when management of a saltwater crocodile egg harvest passed to an Indigenous management group, the number of eggs collected and hatching success of those eggs was lower than when it was run by an external company. Survival (2 studies): One study in the Philippines found that after rural community members were paid a small incentive to protect Philippine crocodile sanctuaries combined with an education and awareness campaign, fewer crocodiles were killed than before community engagement. One before-and-after study in Mozambique found that during a community-based turtle monitoring project no killing of adults was recorded. BEHAVIOUR (0 STUDIES) OTHER (1 STUDY) Human behaviour change (1 study): One replicated study in Colombia found that in areas where communities were engaged in conservation initiatives relating to turtles, more people reported changing consumption habitats and fewer people reported using turtles for food compared to in areas with no initiatives, however, stated rates of hunting, buying and selling of turtles remained similar. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3681https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3681Fri, 10 Dec 2021 14:15:39 +0000Collected Evidence: Collected Evidence: Legally protect reptile species Six studies evaluated the effects of legally protecting reptile species on their populations. Two studies were in the Netherlands and one was in each of the USA, Australia, the Seychelles and Cape Verde. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (3 STUDIES) Abundance (2 studies): One of two studies (including one replicated, site comparison study and one before-and-after study) in the USA and Australia found that waterbodies where turtle harvesting was prohibited had a similar abundance of red-eared sliders and Texas spiny softshell turtles compared to unprotected waterbodies. The other study found that following legal protection and harvest regulation, the density of saltwater crocodile populations increased. Reproductive success (1 studies): One before-and-after study in the Seychelles found that following legal protection of both green turtles and their habitat, nesting activity increased. Condition (2 studies): Two studies (including one replicated, site comparison study and one before-and-after study) in the USA and Australia found that in areas with legal protection and/or harvest regulation, Texas spiny softshell turtles and saltwater crocodiles were larger than in areas with no protection or before protection began. One study also found that female red-eared sliders were larger, but males were a similar size in protected compared to unprotected waterbodies. BEHAVIOUR (0 STUDIES) OTHER (3 studies) Human behaviour change (3 studies): Two reviews in the Netherlands found that despite legislation protecting reptiles and their habitat, only one of four development projects completed their habitat compensation requirements or that compensatory slow worm habitat was not completed in time. Both studies also found that monitoring data was not available or that the success of a slow worm mitigation translocation could not be assessed. One replicated, before-and-after study in Cape Verde reported that following legal protections combined with public awareness campaigns, self-reported harvesting, selling and purchasing of sea turtles and turtle products decreased. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3705https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3705Mon, 13 Dec 2021 10:32:56 +0000Collected Evidence: Collected Evidence: Head-start wild-caught reptiles for release: Crocodilians Seven studies evaluated the effects of head-starting wild-caught crocodilians for release. Two studies were in each of the Philippines and Nepal and one study was in each of Zimbabwe, Venezuela and Argentina. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (7 STUDIES) Abundance (2 studies): Two studies (including one replicated study) in the Philippines and Nepal reported that following releases of head-started crocodiles or gharials, wild populations increased in size over 8–9 years. Reproductive success (2 studies): One replicated study in Argentina reported that released head-started broad-snouted caimans had similar clutch sizes and hatching success compared to non-head-started caiman. One replicated study in Nepal reported successful reproduction in all four rivers where head-started gharials were released. Survival (5 studies): Three studies (including one replicated, controlled study) in Venezuela, the Philippines and Nepal reported that 88% of head-started Orinoco crocodiles survived 8–12 months and 53% of Philippine crocodiles or gharials survived for one year following release. One study also found that survival of Philippine crocodile hatchlings during the captive phase of head-starting was higher than for non-head-started hatchlings in the wild. One replicated study in Argentina reported that at least five released head-started broad-snouted caimans survived 9–10 years. One replicated study in Zimbabwe found that 38% of released head-started Nile crocodiles were recaptured at least once over four years. This study also found that hatching success of Nile crocodile eggs in the head-start programme was 74%, and that survival of hatchlings during the captive phase was lowest during the first year. Condition (1 studies): One study in Venezuela found that released head-started Orinoco crocodiles grew at a similar rate to resident juvenile crocodiles. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3778https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3778Wed, 15 Dec 2021 13:26:54 +0000Collected Evidence: Collected Evidence: Legally protect habitat Ten studies evaluated the effects on butterflies and moths of legally protecting habitat. Six studies were in the UK and one was in each of Australia, Singapore and Ireland and the USA. Three of the studies used data from the same national monitoring scheme across different years. COMMUNITY RESPONSE (3 STUDIES) Richness/diversity (3 studies): One replicated, site comparison study in Singapore found that protected primary or secondary forest reserves had a higher species richness of butterflies than unprotected forest fragments. One replicated, paired, site comparison study in Ireland reported that raised bogs protected as Special Areas of Conservation (where restoration had sometimes taken place) had a similar species richness of moths to unprotected bogs. One replicated, site comparison study in the UK found that, in the first three years after protection as Sites of Special Scientific Interest (SSSI), woodland, grassland and heathland sites lost a similar proportion of 29 threatened butterfly species to unprotected sites. POPULATION RESPONSE (8 STUDIES) Abundance (7 studies): Three of five site comparison studies (including four replicated studies and one before-and-after study) in the UK and Ireland found that sites protected as National Nature Reserves or Sites of Special Scientific Interest (SSSI) (in one case also managed by coppicing), or surrounded by SSSIs, had a higher abundance of heath fritillary, all butterflies and 30/57 species of butterfly than unprotected sites. However, one of these studies only found the result using one of two sets of sites. The other two studies found that grasslands protected as National Nature Reserves or SSSIs and raised bogs protected as Special Areas of Conservation had a similar total abundance of moths, and change in abundance of chalkhill blue butterflies, to unprotected sites. However, one of these studies found mixed results for individual moth species. One replicated, site comparison study in the USA found that, at sites with the highest levels of protection, abundances of Karner blue, frosted elfin and Persius duskywing did not change over time, whereas they decreased at sites with lower levels of protection. One replicated, site comparison study in the UK found that protected grasslands assessed as being in “Favourable” habitat condition had worse population trends for 4/8 butterfly species but better for 1/8 species than grasslands in “Unfavourable” condition. One study in Australia reported that after a grassland was designated as a local reserve, populations of golden sun-moth and pale sun-moth persisted for at least four years. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3831https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3831Mon, 04 Jul 2022 13:36:18 +0100Collected Evidence: Collected Evidence: Coppice woodland Ten studies evaluated the effects on butterflies and moths of coppicing woodland. Eight studies were in the UK and one was in each of France and Germany. COMMUNITY RESPONSE (4 STUDIES) Community composition (3 studies): Two replicated, site comparison studies in the UK and France found that coppiced woodland of different ages supported different communities of moths and butterflies. One replicated, site comparison study in the UK found that coppiced woodland contained more unique species of macro-moth than mature forest. Richness/diversity (4 studies): One of two replicated, site comparison studies in the UK found that coppiced woodland had a greater species richness of butterflies than unmanaged woodland. The other study found that coppiced woodland had a lower species richness of macro-moths than mature forest, and there was no change in species richness with the age of coppice. One of two replicated, site comparison studies in the UK and France found that woodland coppiced two years ago had a greater species richness of butterflies than woodland coppiced >15 years ago. The other study found that the species richness of moths was similar in woodland coppiced 1–4, 5–8 and 12–20 years ago. POPULATION RESPONSE (10 STUDIES) Abundance (9 studies): Two of four site comparison studies (including three replicated studies and one before-and-after study) in the UK found that coppiced woodland (in one case also legally protected) had a higher abundance of butterflies generally, and of heath fritillary specifically, than unmanaged woodland. One study found that pearl-bordered fritillary and small pearl-bordered fritillary populations were more likely to persist for up to 20 years in coppiced woodland (or woodland with young plantations) than in mature conifer woodland. The fourth study found that the abundance of macro-moths was lower in coppiced woodland than in mature forest, and there was no change in abundance with the age of coppice. Three of four replicated, site comparison studies (including one before-and-after study) in the UK, France and Germany found that the abundance of butterflies generally, heath fritillary specifically, and eastern eggar moth and scarce fritillary caterpillar webs, was higher in woodland coppiced two, two–four, five–seven or 12–15 years ago than in woodland coppiced 5–11 or >15 years ago. The fourth study reported that the abundance of moths was similar in woodland coppiced 1–4, 5–8 and 12–20 years ago. One before-and-after study in the UK reported that after coppicing, along with scrub control, tree felling and grazing, high brown fritillary and small pearl-bordered fritillary abundance increased. Reproductive success (1 study): One before-and-after study in the UK reported that pearl-bordered fritillaries released into coppiced woodland bred at least once. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3939https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3939Sat, 13 Aug 2022 14:56:58 +0100Collected Evidence: Collected Evidence: Restore or create peatland Six studies evaluated the effects on butterflies and moths of restoring or creating peatland. Two studies were in each of Finland and the UK, and one was in each of the Netherlands and Ireland. COMMUNITY RESPONSE (3 STUDIES) Community composition (1 study): One replicated, paired, site comparison study in Finland found that mires restored by filling ditches and cutting trees had a moth community which was intermediate between drained and pristine mires. Richness/diversity (2 studies): One replicated, paired, controlled, before-and-after study in Finland found that after mires were restored by raising the water table and removing large trees, they had a higher species richness of mire specialist butterflies than before restoration or than unrestored, drained mires, and a similar species richness to pristine mires. One replicated, paired, site comparison study in Ireland reported that protected bogs re-wetted by blocking drains had a similar species richness of moths to unrestored and unprotected bogs. POPULATION RESPONSE (5 STUDIES) Abundance (4 studies): Two before-and-after studies (including one replicated, paired, controlled study) in the UK and Finland found that bogs re-wetted by blocking drains and mires restored by raising the water table and removing large trees had a higher abundance of rosy marsh moth caterpillars and mire specialist butterflies than before restoration or than unrestored mires, and a similar abundance to pristine mires. Two replicated, paired, site comparison studies in Finland and Ireland found that mires restored by filling ditches and cutting trees and bogs restored by blocking drains (along with legal protection) had mixed effects on moth abundance compared to unrestored sites depending on species. Survival (1 study): One replicated study in the UK found that where water levels had risen due to peatland restoration, large heath butterfly caterpillars had lower winter survival than in areas where water levels had not risen. BEHAVIOUR (1 STUDY) Use (1 study): One replicated, site comparison study in the Netherlands found that wet heathland where water levels had been recently raised were less frequently occupied by Alcon large blue than sites where the water level had not been raised. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3948https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3948Sat, 13 Aug 2022 14:59:56 +0100
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What Works in Conservation

What Works in Conservation provides expert assessments of the effectiveness of actions, based on summarised evidence, in synopses. Subjects covered so far include amphibians, birds, mammals, forests, peatland and control of freshwater invasive species. More are in progress.

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