Collected Evidence: Collected Evidence: Cease or prohibit all types of fishing Five studies examined the effects of ceasing or prohibiting all types of fishing on subtidal benthic invertebrate populations. All studies were in the North Sea (Belgium, Germany, Netherlands, UK).   COMMUNITY RESPONSE (2 STUDIES) Overall community composition (2 studies): Two site comparison studies (one before-and-after) in the North Sea found that areas closed to all fishing developed different overall invertebrate community compositions compared to fished areas. Overall species richness/diversity (2 studies): One of two site comparison studies (one before-and-after) in the North Sea found that areas closed to all fishing did not develop different overall invertebrate species richness and diversity compared to fished areas after three years, but the other found higher species richness in the closed areas after 20 years. POPULATION RESPONSE (3 STUDIES) Overall abundance (2 studies): Two site comparison studies (one before-and-after) in the North Sea found that areas closed to all fishing had similar overall invertebrate abundance and biomass compared to fished areas after three and five years. Crustacean abundance (1 study): One before-and-after, site comparison study in the North Sea found that closing a site to all fishing led to similar numbers of lobster compared to a fished site after 20 months. Crustacean condition (1 study): One before-and-after, site comparison study in the North Sea found that closing a site to all fishing led to larger sizes of lobster compared to a fished site after 20 months. OTHER (1 STUDY) Overall community energy flow (1 study): One before-after, site comparison study in the North Sea found that, during the 12–14 months after closing an area to all fishing, the invertebrate community structure (measured as energy flow) at sites within the closed area did not change, but that it increased in nearby fished sites. Species energy flow (1 study): One before-and-after, site comparison study in the North Sea found that closing an area to all fishing for 12–14 months had mixed effects on species-level energy flow. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2096https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2096Mon, 21 Oct 2019 15:32:10 +0100Collected Evidence: Collected Evidence: Establish temporary fisheries closures Six studies examined the effects of establishing temporary fisheries closures on subtidal benthic invertebrates. One study was in the English Channel (UK), one in the D’Entrecasteaux Channel (Australia), one in the North Pacific Ocean (USA), two in the Mozambique Channel (Madagascar), and one in the North Sea (UK).   COMMUNITY RESPONSE (2 STUDIES) Overall species richness/diversity (1 study): One replicated, site comparison study in the English Channel found that sites seasonally closed to towed-gear fishing did not have greater invertebrate species richness than sites where towed-fishing occurred year-round. Mollusc community composition (1 study): One replicated, before-and after study in the D’Entrecasteaux Channel found that temporarily reopening an area previously closed to all fishing for 12 years only to recreational fishing led to changes in scallop species community composition over four fishing seasons. POPULATION RESPONSE (1 STUDY) Overall abundance (1 study): One replicated, site comparison study in the English Channel found that sites seasonally closed to towed-gear fishing did not have a greater invertebrate biomass than sites where towed-fishing occurred year-round. Crustacean abundance (1 study): One before-and-after, site comparison study in the North Sea found that reopening a site to fishing following a temporary 20-month closure led to lower total abundance but similar marketable abundance of European lobsters compared to a continuously-fished site after a month. Mollusc abundance (5 studies): One replicated, site comparison study English Channel found that sites seasonally closed to towed gear did not have higher abundance of great scallops than sites where towed-fishing occurred year-round. Two before-and after, site comparison studies (one replicated) in the Mozambique Channel found that temporarily closing an area to reef octopus fishing did not increase octopus abundance/biomass compared to before closure and to continuously fished areas. Two replicated, before-and after studies in the D’Entrecasteaux Channel and the North Pacific Ocean found that temporarily reopening an area previously closed to all fishing to recreational fishing only led to a decline in scallop abundance after four fishing seasons and in red abalone after three years. Mollusc condition (3 studies): One replicated, before-and after study in the North Pacific Ocean found that temporarily reopening an area previously closed to fishing led to a decline in the size of red abalone after three years. Two before-and after, site comparison studies (one replicated) in the Mozambique Channel found that temporarily closing an area to reef octopus fishing increased the weight of octopus compared to before closure and to continuously fished areas, but one also found that this effect did not last once fishing resumed. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2098https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2098Tue, 22 Oct 2019 08:34:46 +0100Collected Evidence: Collected Evidence: Modify the design of dredges Six studies examined the effects of modifying the design of dredges on subtidal benthic invertebrate populations. Four were in the North Atlantic Ocean (Portugal) and two were in the Irish Sea (Isle of Man).   COMMUNITY RESPONSE (1 STUDY) Unwanted catch overall composition (1 study): One replicated, controlled, study in the Irish Sea found that a new design of scallop dredge caught a similar species composition of unwanted catch to a traditional dredge. POPULATION RESPONSE (3 STUDIES) Overall abundance (2 studies): One of two controlled studies in the North Atlantic Ocean and in the Irish Sea found that a new dredge design damaged or killed fewer invertebrates left in the sediment tracks following dredging. The other found no difference in total invertebrate abundance or biomass living in or on the sediment tracks following fishing with two dredge designs. Unwanted catch overall abundance (2 studies): Two controlled studies (one replicated) in the North Atlantic Ocean and the Irish Sea found that a modified or a new design of bivalve dredge caught less unwanted catch compared to traditional unmodified dredges. Unwanted catch condition (6 studies): Six controlled studies (one replicated and paired, four replicated) in the North Atlantic Ocean and the Irish Sea found that new or modified bivalve dredges damaged or killed similar proportions of unwanted catch (retained and/or escaped) compared to traditional or unmodified designs, three of which also found that they did not reduce the proportion of damaged or dead unwanted crabs (retained and/or escaped). OTHER (1 study) Commercial catch abundance (1 study): One replicated, controlled, study in the Irish Sea found that a new dredge design caught a similar amount of commercially targeted queen scallops compared to a traditional dredge. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2119https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2119Tue, 22 Oct 2019 09:59:43 +0100Collected Evidence: Collected Evidence: Fit one or more mesh escape panels/windows to trawl nets Seven studies examined the effects of adding one or more mesh escape panels/windows to trawl nets on subtidal benthic invertebrate populations. Six were in the North Sea (Belgium, Netherlands, UK), two in the Thames estuary (UK), one in the English Channel (UK), and one in the Gulf of Carpentaria (Australia).   COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (7 STUDIES) Overall survival (1 study): One replicated, paired, controlled study in the English Channel and the North Sea found that fitting nets with either one of seven designs of square mesh escape panels (varying mesh size and twine type) led to higher survival rates of invertebrates that escaped the nets compared to unmodified nets. Unwanted catch overall abundance (7 studies): Three of seven replicated, paired, controlled studies in the North Sea, the Thames estuary, the English Channel and the Gulf of Carpentaria  found that trawl nets fitted with one or more mesh escape panels/windows/zones reduced the unwanted catch of invertebrates compared to unmodified nets. Two found mixed effects of fitting escape panels on the unwanted catch of invertebrates and fish depending on the panel design. Two found that trawl nets fitted with escape panels  caught similar amounts of unwanted invertebrates and fish compared to unmodified nets. OTHERS (7 STUDIES) Commercially targeted catch abundance (7 studies): Three of seven replicated, paired, controlled studies in the North Sea, the Thames estuary, the English Channel and the Gulf of Carpentaria, found that trawl nets fitted with one or more mesh escape panels/windows/zones caught similar amounts of all or most commercial species to unmodified nets. Three found mixed effects of fitting escape panels on the catch of all or most commercial species depending on the species and/or panel design. One found that trawl nets fitted with escape panels reduced the catch of commercial species compared to unmodified nets. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2132https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2132Tue, 22 Oct 2019 10:33:29 +0100Collected Evidence: Collected Evidence: Restore biogenic habitats (other methods) - Restore oyster reefs Eight studies examined the effects of restoring oyster reefs (not by transplanting or translocating oysters) on oysters and oyster reef-associated subtidal benthic invertebrates. Two were in the Gulf of Mexico (USA), one was a global review, four were in the North Pacific Ocean (USA), and one was in the Mission-Aransas estuary (USA).   COMMUNITY RESPONSE (3 STUDIES) Overall community composition (2 studies): One of two replicated, controlled studies in the Gulf of Mexico and the Mission-Aransas estuary found that after restoring eastern oyster reefs, the community composition of combined mobile decapod invertebrates and fish was similar on all types of restoration material used, but the other found that composition varied with the material used. Overall species richness/diversity (3 studies): One replicated, site comparison study in the Gulf of Mexico found that diversity of reef-associated invertebrates was similar in reefs restored by laying rocks regardless of age, in young reefs restored by laying oyster shells, and in natural reefs, but lower in old shell-restored reefs. One replicated, controlled study in the Gulf of Mexico found that diversity of reef-associated invertebrates was higher in all restored reefs than on unrestored sediment, but that diversity varied between the restoration materials used. One replicated, controlled study in the Mission-Aransas estuary found that diversity of fish, crabs and shrimps varied with the restoration material used. POPULATION RESPONSE (7 STUDIES) Overall abundance (2 studies): One replicated, site comparison study in the Gulf of Mexico found that the effect of restoring eastern oyster reefs on the abundance of reef-associated invertebrates depended on the material used for restoration and the age of the reef. One replicated, controlled study in the Gulf of Mexico found that abundance of combined reef-associated mobile decapod invertebrate and fish was similar on all restored reefs regardless of the restoration material used, and higher than on unrestored sediment. Crustacean abundance (1 study): One replicated, controlled study in the Mission-Aransas estuary found that after restoring eastern oyster reefs, crab abundance, but not biomass, and shrimp biomass, but not abundance, varied with the restoration material used. Oyster abundance (6 studies): One replicated, site comparison study in the Gulf of Mexico found that oyster reefs restored by laying rocks had similar oyster abundance to natural reefs, and higher than reefs restored by laying oyster shells. One replicated, controlled study in the Mission-Aransas estuary found that oyster cover and abundance varied with the restoration material used. One replicated, controlled study in the Gulf of Mexico found that oyster spat abundance was similar on all types of restoration material used, and higher than on unrestored sediment. Three replicated, controlled studies in the North Pacific Ocean found that restoring oyster reefs by placing lines of clam shells below Mean Lower Low Water (MLLW) led to higher cover of clam shells by oysters than when placing the lines above MLLW, that for those placed below MLLW, keeping them there led to similar cover compared to moving them above MLLW halfway through the study, and that placing the lines on cobbly seabed led to similar cover compared to placing them on muddy seabed. Oyster reproductive success (3 studies): Three replicated, controlled studies in the North Pacific Ocean found that restoring oyster reefs by placing lines of clam shells below Mean Lower Low Water (MLLW) led to higher recruitment of oyster spat on clam shells than by lacing lines above MLLW, that recruitment was higher on lines placed on cobbly seabed than on muddy seabed, and that recruitment was similar on lines placed near or far from the nearest adult oyster populations. Oyster survival (5 studies): One global systematic review found that two of nine restoration techniques (restoring oyster reef by transplanting juveniles, and by creating no-harvest sanctuaries) assessed resulted in over 85% survival of restored oysters. Four replicated, controlled studies in the North Pacific Ocean found that restoring oyster reefs by placing lines of clam shells below Mean Lower Low Water (MLLW) led to similar survival of oysters than when placing the lines above MLLW, but that for those placed below MLLW, moving them above MLLW halfway through the study led to higher survival than keeping then below, that survival was similar on lines placed on cobbly seabed or muddy seabed, and that survival was similar on lines placed near or far from the nearest adult oyster populations. Oyster condition (5 studies): One replicated, controlled study in the Gulf of Mexico found that the effect of restoring eastern oyster reefs on average spat size varied with the restoration material used. One replicated, controlled study in the North Pacific Ocean found that restoring oyster reefs by placing lines of clam shells below Mean Lower Low Water (MLLW) led to similar growth of oysters on the shells than placing lines above MLLW. Four replicated, controlled studies in the North Pacific Ocean found that restoring oyster reefs by placing lines of clam shells below Mean Lower Low Water (MLLW) led to higher cover of clam shells by non-native species than placing lines above MLLW, but that for those placed below MLLW, moving them above MLLW halfway through the study led to lower cover than keeping then below, that cover was similar on lines placed on cobbly seabed or muddy seabed, and that cover of clam shells by non-native species was higher on lines placed near compared to far from the nearest adult oyster populations. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2248https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2248Wed, 23 Oct 2019 09:37:47 +0100Collected Evidence: Collected Evidence: Exclude or limit number of visitors to reserves or protected areas Five studies evaluated the effects on mammals of excluding or limiting the number of visitors to reserves or protected areas. Three studies were in the USA, one was in Ecuador and one was in Thailand. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (2 STUDIES) Abundance (1 study): A site comparison study in Ecuador found that a road with restricted access had a higher population of medium-sized and large mammals compared to a road with unrestricted access. Survival (1 study): A before-and-after study in the USA found that temporarily restricting visitor access resulted in fewer bears being killed to protect humans. BEHAVIOUR (3 STUDIES) Use (3 studies): Three studies (one a before-and-after study), in the USA and Thailand, found that restricting human access to protected areas resulted in increased use of these areas by grizzly bears and leopards. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2330https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2330Thu, 21 May 2020 10:43:02 +0100Collected 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: Pay farmers to compensate for losses due to predators/wild herbivores to reduce human-wildlife conflict Five studies evaluated the effects on mammals of paying farmers compensation for losses due to predators or wild herbivores to reduce human-wildlife conflict. Three studies were in Kenya and one each was in Italy and Sweden. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (5 STUDIES) Abundance (2 studies): Two studies, in Italy and Sweden, found that compensating livestock owners for losses to predators led to increasing populations of wolves and wolverines. Survival (3 studies): Three before-and-after studies (including two replicated studies), in Kenya, found that when pastoralists were compensated for livestock killings by predators, fewer lions were killed. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2414https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2414Fri, 29 May 2020 15:48:47 +0100Collected Evidence: Collected Evidence: Use flags to reduce predation of livestock by mammals to reduce human-wildlife conflict Five studies evaluated the effects on mammals of using flags to reduce predation of livestock by mammals to reduce human-wildlife conflict. Three studies were in the USA, one was in Italy and one was in Canada. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (0 STUDIES) OTHER (5 STUDIES) Human-wildlife conflict (5 studies): Three studies (including two before-and-after studies and a controlled study), in Italy, Canada and the USA, found that flags hanging from fence lines (fladry) deterred crossings by wolves but not by coyotes. A further replicated, controlled study in the USA found that electric fences with fladry were not crossed by wolves. A replicated, controlled, before-and-after study in the USA found that fladry did not reduce total deer carcass consumption by a range of carnivores. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2421https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2421Mon, 01 Jun 2020 13:54:30 +0100Collected Evidence: Collected Evidence: Deter predation of livestock by using shock/electronic dog-training collars to reduce human-wildlife conflict Five studies evaluated the effects of using shock/electronic dog-training collars to deter predation of livestock to reduce human-wildlife conflict. All five studies were in the USA. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (0 STUDIES) OTHER (5 STUDIES) Human-wildlife conflict (5 studies): Three of four replicated studies (including two controlled studies), in the USA, found that electric shock collars reduced livestock predation or bait consumption by wolves, whilst one found that they did not reduce wolf bait consumption. One replicated, controlled study in the USA found that electric shock collars reduced the frequency of attacks by captive coyotes on lambs. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2446https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2446Tue, 02 Jun 2020 10:37:37 +0100Collected Evidence: Collected Evidence: Release translocated/captive-bred mammals in larger unrelated groups Five studies evaluated the effects of releasing translocated or captive-bred mammals in larger unrelated groups. Two studies were in South Africa, one was in Namibia and South Africa, one was in the USA and one was in Australia. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (5 STUDIES) Reproductive success (3 studies): A replicated, paired sites study in the USA found that black-tailed prairie dogs translocated in larger groups had higher reproductive success than smaller groups. A study in South Africa found that Cape buffalo translocated to a fenced reserve as a larger group formed a single herd and reproduced, whilst a smaller group separated. A study in South Africa found that rehabilitated and captive-bred cheetahs released in groups (unrelated and family) and as individuals reproduced. Survival (4 studies): A replicated, paired sites study in the USA found that black-tailed prairie dogs translocated in larger groups had higher initial daily survival rate than smaller groups. Two studies (one controlled) in Namibia and South Africa and Australia found that releasing translocated black rhinoceroses and burrowing bettongs in larger groups did not increase survival. A study in South Africa found that most adult rehabilitated and captive-bred cheetahs released in groups (unrelated and family) and as individuals survived at least one year. BEHAVIOUR (2 STUDIES) Behaviour change (2 studies): A replicated, paired sites study in the USA found that black-tailed prairie dogs translocated in larger groups attracted more immigrants than smaller groups. A study in South Africa found that Cape buffalo translocated as a larger group formed a single herd and stayed in the fenced reserve, whilst a smaller group scattered and escaped the reserve. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2462https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2462Tue, 02 Jun 2020 12:01:41 +0100Collected Evidence: Collected Evidence: Use target species distress calls or signals to deter crop damage by mammals to reduce human-wildlife conflict Five studies evaluated the effects of using target species distress calls or signals to deter crop damage by these species to reduce human-wildlife conflict. Two studies were in the USA and one each was in Namibia, Australia and Sri Lanka. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (0 STUDIES) OTHER (5 STUDIES) Human-wildlife conflict (5 studies): Two of five replicated studies (including four controlled studies), in the USA, Namibia, Australia and Sri Lanka, found that white-tailed deer and Asian elephants were deterred or repelled from areas by playing their respective distress calls. Two studies found that, in most cases, elephants and white-tailed deer were not deterred from entering or remaining at sites when distress calls were played. The fifth study found mixed results but, overall, eastern grey kangaroo foot-thumping noises did not increase numbers leaving a site. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2488https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2488Thu, 04 Jun 2020 13:14:16 +0100Collected Evidence: Collected Evidence: Restore or create forest Five studies evaluated the effects on mammals of restoring or creating forest. Two studies were in the USA and one each were in Colombia, Italy and Australia. COMMUNITY RESPONSE (2 STUDIES) Richness/diversity (2 studies): Two site comparison studies (one replicated) in the USA and Colombia found that mammal species richness in restored forest was similar to that in established forest. POPULATION RESPONSE (2 STUDIES) Abundance (2 studies): One of two replicated studies (one a site comparison) in Australia and Italy found that replanted or regrowing forest supported a higher abundance of hazel dormice than did coppiced forest. The other study found only low numbers of common brushtail possums or common ringtail possums by 7–30 years after planting. BEHAVIOUR (1 STUDY) Usage (1 study): A replicated, site comparison study in the USA found that restored riparian forest areas were visited more by carnivores than were remnant forests when restored areas were newly established, but not subsequently, whilst restored areas were not visited more frequently by black-tailed deer. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2570https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2570Tue, 09 Jun 2020 17:06:23 +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: 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: Provide mammals with escape routes from canals Five studies evaluated the effects on mammals of providing mammals with escape routes from canals. Two studies were in Germany and one each was in the USA, the Netherlands and Argentina. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (2 STUDIES) Survival (2 studies): One of two studies (one before-and-after), in Germany and the USA, found that ramps and ladders reduced mule deer drownings whilst the other study found that ramps and shallow-water inlets did not reduce mammal drownings. BEHAVIOUR (3 STUDIES) Use (3 studies): Three studies (one replicated) in Germany, the Netherlands and Argentina, found that ramps and other access or escape routes out of water were used by a range of medium-sized and large mammals species. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2638https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2638Fri, 12 Jun 2020 13:06:54 +0100Collected Evidence: Collected Evidence: Establish long-term fishery closures Five studies examined the effects of establishing long-term fishery closures in an area on marine fish populations. One study was in each of the Norwegian Sea (Norway), the North Sea (UK), the Gulf of Maine (USA), the Bismark Sea (Papua New Guinea) and the Kattegat (Sweden/Denmark). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (4 STUDIES) Condition (2 studies): One replicated, before-and-after study in the Norwegian Sea found that in the five years after the long-term closure of a commercial coastal fishery, the weights of young salmon returning to rivers were higher than before, and weights of older salmon were similar or lower. One site comparison study in the Gulf of Maine found that there were smaller, but similar condition monkfish inside an area closed year-round to groundfish fishing for six to seven years than an area open to all fishing. Abundance (4 studies): Two site comparison studies in the Gulf of Maine and Bismark Sea found a higher abundance of only one of seven fish species and lower abundance of monkfish in areas closed to groundfish (bottom-dwelling) fisheries for six to eight years, compared to open areas. One of two replicated, before-and-after studies (one controlled) in the Norwegian Sea and North Sea found that there were more young salmon and similar numbers of older salmon returning to rivers than before, in the five years after the long-term closure of a commercial coastal fishery. The other study found that lesser sandeel biomass and density peaked but there was no overall increase in the three years after a long-term fishery closure compared to before. BEHAVIOUR (1 STUDY) Behaviour change (1 study): One site comparison study in the Bismark Sea found that in an area closed to customary fishing for eight years, six of seven fish species had a lower flight response distance compared to an area open to customary fishing, making them more vulnerable to capture with spear guns. OTHER (3 STUDIES) Reduction of unwanted catch (1 study): One replicated, before-and-after study in the Kattegat found that a combination of long-term fishery closures and areas limited to specific gears reduced unwanted catch of cod compared to before. Reduction of fishing effort (1 study): One replicated, controlled, before-and-after study in the North Sea found that long-term closure of a commercial fishery reduced overall fishing effort for lesser sandeel. Commercial catch abundance (1 study): One replicated, controlled, before-and-after study in the North Sea found that annual sandeel catch rates were varied after the indefinite closure of the commercial fishery in an area. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2655https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2655Thu, 12 Nov 2020 14:53:37 +0000Collected Evidence: Collected Evidence: Establish temporary fishery closures Five studies examined the effects of establishing temporary fishery closures on marine fish populations. Two studies were in the North Atlantic Ocean (Canada, UK) and one study was in each of the North Sea (UK), the Philippine Sea (Palau) and the Mediterranean Sea (Spain).  COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Abundance (1 study): One before-and-after, site comparison study in the Atlantic Ocean found no increase in the biomass of the spawning stock of cod following a temporary fishery closure compared to fished areas over nine years. Survival (1 study): One before-and-after, site comparison study in the Atlantic Ocean found no change in the survival of cod following a temporary fishery closure compared to fished areas over nine years. Condition (1 study): One before-and-after, site comparison study in the Atlantic Ocean found no change in the length composition of cod following a temporary fishery closure, compared to fished areas over nine years. BEHAVIOUR (1 STUDY) Use (1 study): A study in the Northeast Atlantic Ocean reported that over five years tagged adult cod spent nearly a third of time inside a seasonally closed cod spawning area during implementation, and were thus given increased protection from any gears targeting bottom-dwelling fish during the spawning period. OTHER (4 STUDIES) Reduction of fishing effort (1 study): One replicated, controlled, before-and-after study in the North Sea found that fixed temporary closures had little effect on fishing effort for cod, but real-time area closures reduced the annual amount of cod caught (retained and discarded). Commercial catch abundance (3 studies): One of two replicated (one controlled, one before-and-after) studies in the Philippine Sea and Mediterranean Sea found that during a temporary closure of a grouper fishery, spear fisher catch numbers of other fish groups (herbivores) increased, indicating they were being targeted more compared to the open season. The other study found that in targeted fisheries over 10 years, catch rates of red mullet and total catch (fish and invertebrates combined), but not European hake, increased after temporary closures, compared to before. One before-and-after, site comparison study in the Atlantic Ocean found no change over nine years in cod catches following a temporary fishery closure compared to fished areas. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2664https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2664Wed, 18 Nov 2020 16:03:49 +0000Collected Evidence: Collected Evidence: Cease or prohibit spearfishing Five studies examined the effects of ceasing or prohibiting spearfishing in an area on marine fish populations. Two studies were in the Mediterranean Sea (France, Corsica). One study was in each of the Tasman Sea (Australia) and the Indian Ocean (South Africa). One study was a review of marine reserves around the world. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (4 STUDIES) Abundance (4 studies): Two of three site comparison studies in the Mediterranean Sea, the Tasman Sea and the Indian Ocean found that prohibiting spearfishing, and line fishing, in protected areas increased the abundances of European seabass and gilthead seabream (years unknown) and of coral reef fish species, compared to protected and unprotected fished areas, after two to seven years. The other study found that fish densities differed between spearfished and non-spearfished areas after 10–12 years, and was affected by depth and/or fish size. A review of reef marine reserves around the world reported that two non-spearfished reserves in the northwestern Atlantic had more snappers and grunts after two years in one, and higher densities of reef fish, including snappers and grunts after 20 years in the other, compared to nearby fished reefs. Condition (3 studies): Two site comparison studies in the Mediterranean Sea and the Indian Ocean found that prohibiting spearfishing (and linefishing) in marine protected areas resulted in larger European seabass and coral reef fish species, compared to protected and unprotected fished areas, after two to seven years. A review of global reef marine reserves reported that reef fish were larger in one reserve in the northwestern Atlantic that had banned spearfishing for 20 years, compared to nearby fished reefs. BEHAVIOUR (0 STUDIES) OTHER (1 STUDY)  Commercial catch abundance (1 study): One replicated, site-comparison study in the Mediterranean Sea found that prohibiting spearfishing in specific zones of a marine reserve resulted in higher commercial and recreational fishery catches of targeted common dentex compared to zones that allowed spearfishing and areas outside the reserve after one to three years.    Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2672https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2672Fri, 20 Nov 2020 09:32:23 +0000Collected Evidence: Collected Evidence: Deploy fishing gear at selected depths to avoid unwanted species Five studies examined the effect of deploying fishing gear at selected depths to avoid unwanted species on marine fish populations. Three studies were in the Atlantic Ocean (Florida, Brazil, Canary Islands), and one study was in each of the Pacific Ocean (Hawaii) and the Tasman Sea (Australia). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (0 STUDIES) OTHER (5 STUDIES) Reduction of unwanted catch (5 studies): Four of five replicated studies (three controlled, one paired and controlled) in the Pacific Ocean, Atlantic Ocean and the Tasman Sea found that deploying fishing gear (longlines, handlines and traps) at selected depths, including above the seabed instead of on it, reduced the unwanted catches of five of 17 fish species, three of eight shark/ray species, non-commercially targeted fish species and Harrison’s dogfish, compared to depths usually fished. The other study found that different shark species were hooked at different depths in the water column during bottom-set longlining deployments.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2683https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2683Mon, 30 Nov 2020 16:26:13 +0000Collected Evidence: Collected Evidence: Use a different twine type in a trawl net Five studies examined the effects of using a different twine type in a trawl net on marine fish populations. Two studies were in each of the North Sea (UK) and the Western Baltic Sea (Denmark/Germany), and one study was in the Adriatic Sea (Italy). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (0 STUDIES) OTHER (5 STUDIES) Improved size-selectivity of fishing gear (5 studies): Four of five replicated studies (four controlled) in the North Sea, Baltic Sea and Adriatic Sea found that using a different twine type (twine thickness and construction material) improved the size-selectivity of bottom fish, haddock, Atlantic cod, plaice and flounder, compared to thinner or other twine materials. One study found that selectivity of non-target haddock and plaice was similar for three different twine diameters. One of these studies also found that size-selectivity of fish was influenced by twine number and mesh orientation, while another found no effect of twine number and mesh orientation, but cod selectivity increased with a smaller codend circumference. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2710https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2710Tue, 29 Dec 2020 16:07:09 +0000Collected Evidence: Collected Evidence: Set a minimum landing size for commercially fished species Five studies examined the effects of setting a minimum landing size for commercially fished species on marine fish populations. One study was a global review and one study was in each of the Tasman Sea (Australia), the Baltic Sea (Northern Europe), the Ionian Sea (Greece) and the Northwest Atlantic Ocean (USA). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (2 STUDIES) Reproductive success (2 studies): One global review reported that one of five swordfish fisheries showed an increase in swordfish recruitment after the setting of recommended minimum landing sizes and catch limits, with recruitment in the other fisheries either highly variable or unable to be assessed. One replicated study in the Ionian Sea reported that, despite established minimum sizes, most fish landed in commercial catches were immature, and thus had never spawned. BEHAVIOUR (0 STUDIES) OTHER (3 STUDIES) Reduction of unwanted catch (3 studies): One of three before-and-after studies (one replicated) in the Atlantic Ocean, Tasman Sea and Baltic Sea found that following an increase in the set minimum landing size and mesh size of gill nets the catches of the youngest southern flounder were reduced. The other two found that increasing the minimum landing size did not reduce the catches of discarded dusky flathead and Atlantic cod3, and discarding of flathead increased in one of three cases. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2735https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2735Tue, 02 Feb 2021 14:28:08 +0000Collected Evidence: Collected Evidence: Introduce fragments of non-woody plants: freshwater wetlands Five studies evaluated the effects, on vegetation, of introducing fragments of emergent, non-woody plants to freshwater wetlands. Three studies were in the USA. Two studies were in one marsh in Australia, but used different experimental set-ups. VEGETATION COMMUNITY   VEGETATION ABUNDANCE Overall abundance (2 studies): Two replicated, randomized, paired, controlled, before-and-after studies in a floodplain marsh in Australia found that plots planted with wick grass Hymenachne acutigluma had similar overall vegetation cover to unplanted plots after one year. One of the studies continued for longer, and found that planted plots had greater overall vegetation cover than unplanted plots after three years. Herb abundance (1 study): One replicated, randomized, paired, controlled, before-and-after study in a floodplain marsh in Australia found that plots planted with wick grass Hymenachne acutigluma had similar overall sedge/grass cover to unplanted plots after one year. Individual species abundance (4 studies): Four studies quantified the effect of this action on the abundance of individual plant species. For example, of two replicated, randomized, paired, controlled, before-and-after studies in a floodplain marsh in Australia, one found that wick grass Hymenachne acutigluma was more frequent and had greater cover, after 1–3 years, in plots where its runners had been planted than where they had not been planted. The other study reported that wick grass cover was present, with approximately 1% cover, in 5 of 10 plots where its runners had been planted. This study monitored vegetation one year after planting. VEGETATION STRUCTURE   OTHER Germination/emergence (1 study): One replicated, randomized, paired, controlled study in a floodplain marsh in Australia found that planting wick grass Hymenachne acutigluma had no significant effect on the germination rate of invasive mimosa Mimosa pigra over three years. Survival (5 studies): Two replicated studies planted sedge Carex fragments into freshwater wetlands in the USA. One study reported 38–79% survival of planted tubers over one growing season, whilst the other study reported 0–73% survival of planted rhizomes after 1–9 months. One replicated study in a tidal freshwater marsh in the USA reported that 6–31% of planted California bulrush Schoenoplectus californicus rhizomes had produced shoots after three months. For two other species, all planted rhizomes died within three months. Two replicated, randomized, paired, controlled, before-and-after studies in a floodplain marsh in Australia reported absence of planted wick grass Hymenachne acutigluma from 17–50% of plots after one year. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3260https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3260Sat, 10 Apr 2021 13:28:02 +0100Collected Evidence: Collected Evidence: Use fences or barriers to protect freshwater wetlands planted with trees/shrubs Five studies evaluated the effects, on vegetation, of using fences or barriers to protect freshwater wetlands planted with trees/shrubs. Four studies were in the USA and one was in Australia. VEGETATION COMMUNITY   VEGETATION ABUNDANCE Tree/shrub abundance (1 study): One replicated, paired, controlled study in a floodplain swamp clearing in the USA found that amongst plots sown with tree seeds, fencing to exclude deer had no significant effect on total tree seedling density after three years. VEGETATION STRUCTURE Height (2 studies): One replicated, paired, controlled study in a floodplain swamp clearing in the USA found that amongst plots sown with tree seeds, those also fenced to exclude deer contained taller tree seedlings, after three years, than those left unfenced. One replicated, paired, controlled study in created freshwater wetlands in the USA found that the average height of white cedar Thuja occidentalis saplings typically increased by a similar amount, between two and five years after planting, in plots fenced to exclude deer and plots left unfenced. OTHER Survival (3 studies): One replicated, paired, controlled study in floodplain swamps in Australia reported that planted swamp gum Eucalyptus camphora seedlings had a much higher survival rate, over one year, in plots fenced to exclude mammals than in open plots. Two replicated, paired, controlled studies in freshwater wetlands in the USA reported that exclusion fencing sometimes increased survival of planted tree seedlings but sometimes had no clear or significant effect. This depended on factors such as the season of planting, seedling elevation, and site. Growth (1 study): One replicated, randomized, controlled study in a nutria-invaded wetland in the USA found that planted baldcypress Taxodium distichum seedlings grew more, over one growing season, when protected than when left unprotected. Plastic guards increased height and diameter growth rates. Sticky, insect-repellent oil increased the growth rate for height, but not diameter. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3330https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3330Sun, 11 Apr 2021 13:15:05 +0100Collected Evidence: Collected Evidence: Remove vegetation that could compete with planted trees/shrubs: freshwater wetlands Five studies evaluated the effects, on trees/shrubs planted in freshwater wetlands, of removing competing plants. Four studies were in the USA. Two of these took place in the same swamp, but with different experimental set-ups. One study was in Australia. VEGETATION COMMUNITY   VEGETATION ABUNDANCE   VEGETATION STRUCTURE Height (3 studies): Three replicated, controlled studies (two also randomized, two also paired) in a wet meadow in Australia and a degraded swamp in the USA found that clearing vegetation before planting tree/shrub seedlings typically had no clear or significant effect on their height, after 1–4 growing seasons. However, one of the studies in the USA found that planted baldcypress Taxodium distichum seedlings were taller, after three growing seasons, when planted amongst cut woody vegetation than below an uncleared canopy. Diameter/perimeter/area (1 study): One replicated, randomized, paired, controlled study in a wet meadow in Australia found that clearing vegetation, before planting tree/shrub seedlings, typically had no significant effect on the diameter of these seedlings nine months later. OTHER Germination/emergence (1 study): One replicated, randomized, paired, controlled study in a wet meadow in Australia found that there were more seedlings in plots that had been cleared of vegetation before sowing tree/shrub seeds, than in plots that had not been cleared before sowing. Seedlings were counted two months after sowing. Survival (4 studies): Three replicated, controlled studies (two also randomized, two also paired) in a wet meadow in Australia and a degraded swamp in the USA found that clearing vegetation before planting tree/shrub seedlings typically had no clear or significant effect on their survival, after 1–4 growing seasons. However, one of the studies in the USA found that planted baldcypress Taxodium distichum seedlings had a lower survival rate, after three growing seasons, when planted amongst cut woody vegetation than below an uncleared canopy. One replicated, randomized, paired, controlled study in degraded swamps in the USA found that removing reed canarygrass Phalaris arundinacea before planting tree/shrub seedlings never significantly reduced their survival rate over 1–2 growing seasons, and often increased it. Growth (1 study): One replicated, randomized, controlled study in the USA found that baldcypress Taxodium distichum seedlings planted into a marsh grew more in diameter, but less in height, when planted into plots cleared of vines than when planted into uncleared plots. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3334https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3334Sun, 11 Apr 2021 14:09:05 +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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