Collected Evidence: Collected Evidence: Introduce and enforce legislation to prevent intentional killing of mammals at aquaculture systems We found no studies that evaluated the effects of introducing and enforcing legislation to prevent intentional killing of mammals at aquaculture systems. ‘We found no studies’ means that we have not yet found any studies that have directly evaluated this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2745https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2745Tue, 02 Feb 2021 16:43:17 +0000Collected Evidence: Collected Evidence: Install diversion or return systems on cooling water intake structures We found no studies that evaluated the effects of installing diversion or return systems on cooling water intake structures on marine and freshwater mammal populations. ‘We found no studies’ means that we have not yet found any studies that have directly evaluated this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2750https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2750Tue, 02 Feb 2021 16:50:44 +0000Collected Evidence: Collected Evidence: Introduce and enforce legislation to prevent intentional killing of mammals at wild fisheries We found no studies that evaluated the effects of introducing and enforcing legislation to prevent intentional killing of mammals at wild fisheries. ‘We found no studies’ means that we have not yet found any studies that have directly evaluated this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2778https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2778Thu, 04 Feb 2021 15:51:27 +0000Collected Evidence: Collected Evidence: Introduce alternative treatments to reduce the use of marine and freshwater mammals in traditional medicine We found no studies that evaluated the effects of introducing alternative treatments to reduce the use of marine and freshwater mammals in traditional medicine. ‘We found no studies’ means that we have not yet found any studies that have directly evaluated this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2783https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2783Thu, 04 Feb 2021 16:19:10 +0000Collected Evidence: Collected Evidence: Introduce alternative food sources to replace marine and freshwater mammal meat We found no studies that evaluated the effects of introducing alternative food sources to replace marine and freshwater mammal meat. ‘We found no studies’ means that we have not yet found any studies that have directly evaluated this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2784https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2784Thu, 04 Feb 2021 16:21:34 +0000Collected Evidence: Collected Evidence: Introduce alternative income sources to reduce marine and freshwater mammal exploitation and trade We found no studies that evaluated the effects of introducing alternative income sources to reduce marine and freshwater mammal exploitation and trade. ‘We found no studies’ means that we have not yet found any studies that have directly evaluated this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2785https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2785Thu, 04 Feb 2021 16:22:40 +0000Collected Evidence: Collected Evidence: Introduce alternative sources of bait to replace the use of marine and freshwater mammals We found no studies that evaluated the effects of introducing alternative sources of bait to replace the use of marine and freshwater mammals. ‘We found no studies’ means that we have not yet found any studies that have directly evaluated this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2786https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2786Thu, 04 Feb 2021 16:23:36 +0000Collected Evidence: Collected Evidence: Inform local communities and fishers about the negative impacts of hunting to reduce the killing of marine and freshwater mammals We found no studies that evaluated the effects of informing local communities and fishers about the negative impacts of hunting to reduce the killing of marine and freshwater mammals. ‘We found no studies’ means that we have not yet found any studies that have directly evaluated this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2787https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2787Thu, 04 Feb 2021 16:24:44 +0000Collected Evidence: Collected Evidence: Increase visual detectability of fishing gear for mammals Two studies evaluated the effects on marine mammals of increasing the visual detectability of fishing gear for mammals. One study was in the Gulf of St. Lawrence (Canada) and one was in Cape Cod Bay (USA). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (2 STUDIES) Behaviour change (2 studies): One study in the Gulf of St. Lawrence found that minke whales approached white ropes more slowly and changed their bearing more when approaching black ropes compared to ropes of other colours. One study in Cape Cod Bay found that simulated ropes painted red or orange were detected by North Atlantic right whales at greater distances than green but not black ropes, and more whales collided with green ropes than the other three rope colours. Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2805https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2805Thu, 04 Feb 2021 17:16:45 +0000Collected Evidence: Collected Evidence: Install exclusion and/or escape devices for mammals on fishing nets Seven studies evaluated the effects on marine mammals of installing exclusion and/or escape devices on fishing nets. Four studies were in the Indian Ocean (Australia, Tasmania) and/or Tasman Sea (Tasmania) and three studies were in the South Atlantic Ocean (South Georgia). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (2 STUDIES) Survival (2 studies): One study in the Indian Ocean found that less than one third of common bottlenose dolphins exited escape hatches on trawl nets alive. One replicated study in the Tasman Sea and Indian Ocean found that fewer fur seals died in exclusion devices with large escape openings than in those with small openings. BEHAVIOUR (0 STUDIES) OTHER (5 STUDIES) Reduction in entanglements/unwanted catch (5 studies): Three studies (including two controlled studies) in the South Atlantic Ocean and Indian Ocean found that installing exclusion and/or escape devices on trawl nets reduced the number of trapped or entangled Antarctic fur seals and common bottlenose dolphins. One before-and-after study in the Indian Ocean found that installing exclusion and escape devices on trawl nets reduced common bottlenose dolphin entanglements for three of four fishing vessels. One study in the South Atlantic Ocean found that modifying an exclusion and escape device by enlarging and relocating the escape panel resulted in fewer Antarctic fur seal entanglements. Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2823https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2823Fri, 05 Feb 2021 15:39:04 +0000Collected Evidence: Collected Evidence: Install barriers at wild fisheries One study evaluated the effects on freshwater mammals of installing a barrier at a wild fishery. The study was in the Puntledge River (Canada). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (0 STUDIES) OTHER (1 STUDY) Human-wildlife conflict (1 study): One randomized, controlled study in the Puntledge River found that installing a ‘cork line’ barrier did not deter harbour seals from feeding on salmon released from a hatchery. Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2824https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2824Fri, 05 Feb 2021 15:52:33 +0000Collected Evidence: Collected Evidence: Establish handling and release protocols for mammals captured by fisheries One study evaluated the effects on marine mammals of establishing handling and release protocols for mammals captured by wild fisheries. The study was in the Great Australian Bight (Australia). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Survival (1 study): One before-and-after study in the Great Australian Bight found that introducing a code of conduct for releasing dolphins trapped in nets, along with avoiding dolphins during fishing, resulted in lower mortality of short-beaked common dolphins. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2829https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2829Fri, 05 Feb 2021 16:02:48 +0000Collected Evidence: Collected Evidence: Finance low interest loans to convert to fishing gear that reduces unwanted catch of mammals We found no studies that evaluated the effects of financing low interest loans to convert to fishing gear that reduces unwanted catch of mammals on marine and freshwater mammal populations. ‘We found no studies’ means that we have not yet found any studies that have directly evaluated this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2835https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2835Fri, 05 Feb 2021 16:08:28 +0000Collected Evidence: Collected Evidence: Inform the public of ways to reduce disturbance to marine and freshwater mammals (e.g. use educational signs) One study evaluated the effects of informing the public of ways to reduce disturbance to marine and freshwater mammals. The study was in the South Pacific Ocean (New Zealand). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (0 STUDIES) OTHER (1 STUDY) Change in human behaviour (1 study): One controlled study in the South Pacific Ocean found that tourist groups that observed information signs approached and disturbed New Zealand fur seals in similar numbers to those that did not. Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2843https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2843Fri, 05 Feb 2021 16:24:16 +0000Collected Evidence: Collected Evidence: Install bypass channels in dams We found no studies that evaluated the effects of installing bypass channels in dams on marine and freshwater mammal populations. ‘We found no studies’ means that we have not yet found any studies that have directly evaluated this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2848https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2848Fri, 05 Feb 2021 16:37:32 +0000Collected Evidence: Collected Evidence: Establish pollution emergency plans We found no studies that evaluated the effects of establishing emergency pollution plans on marine and freshwater mammal populations. ‘We found no studies’ means that we have not yet found any studies that have directly evaluated this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2862https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2862Mon, 08 Feb 2021 11:24:01 +0000Collected Evidence: Collected Evidence: Establish riparian buffers to reduce the amount of pollutants reaching rivers and the sea We found no studies that evaluated the effects of establishing riparian buffers to reduce the amount of pollutants reaching rivers and the sea on marine and freshwater mammal populations. ‘We found no studies’ means that we have not yet found any studies that have directly evaluated this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2882https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2882Mon, 08 Feb 2021 11:46:21 +0000Collected Evidence: Collected Evidence: Establish aquaculture to extract the nutrients from run-offs We found no studies that evaluated the effects of establishing aquaculture to extract the nutrients from run-offs on marine and freshwater mammal populations. ‘We found no studies’ means that we have not yet found any studies that have directly evaluated this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2883https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2883Mon, 08 Feb 2021 11:47:05 +0000Collected Evidence: Collected Evidence: Improve methods for locating fishing gear We found no studies that evaluated the effects of improving methods for locating fishing gear on marine and freshwater mammal populations. ‘We found no studies’ means that we have not yet found any studies that have directly evaluated this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2889https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2889Mon, 08 Feb 2021 11:51:49 +0000Collected Evidence: Collected Evidence: Establish fishing gear registration programmes We found no studies that evaluated the effects of establishing fishing gear registration programmes on marine and freshwater mammal populations. ‘We found no studies’ means that we have not yet found any studies that have directly evaluated this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2890https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2890Mon, 08 Feb 2021 11:52:28 +0000Collected Evidence: Collected Evidence: Inform fishers of the impacts of derelict fishing gear on mammals to encourage responsible disposal We found no studies that evaluated the effects of informing fishers of the impacts of derelict fishing gear on mammals to encourage responsible disposal. ‘We found no studies’ means that we have not yet found any studies that have directly evaluated this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2891https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2891Mon, 08 Feb 2021 11:53:08 +0000Collected Evidence: Collected Evidence: Install stormwater traps or grids We found no studies that evaluated the effects of installing stormwater traps or grids on marine and freshwater mammal populations. ‘We found no studies’ means that we have not yet found any studies that have directly evaluated this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2894https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2894Mon, 08 Feb 2021 11:58:26 +0000Collected Evidence: Collected Evidence: Implement rapid response plans for stranded mammals following extreme events We found no studies that evaluated the effects of implementing rapid response plans for stranded mammals following extreme events. ‘We found no studies’ means that we have not yet found any studies that have directly evaluated this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2911https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2911Mon, 08 Feb 2021 16:20:50 +0000Collected Evidence: Collected Evidence: Establish a network of legally protected areas We found no studies that evaluated the effects of establishing a network of legally protected areas on marine and freshwater mammal populations. ‘We found no studies’ means that we have not yet found any studies that have directly evaluated this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2913https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2913Mon, 08 Feb 2021 16:23:32 +0000Collected Evidence: Collected Evidence: Hand-rear orphaned or abandoned marine and freshwater mammal young Twelve studies evaluated the effects of hand-rearing orphaned or abandoned marine and freshwater mammal young. Four studies were in the North Pacific Ocean (USA), two studies were in captive facilities (USA), and one study was in each of the North Atlantic Ocean (USA), the Indian River Lagoon (USA), the Salish Sea (USA), the Guerrero Lagoon (USA), the South Atlantic Ocean (Brazil) and water bodies in Florida (USA). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (11 STUDIES) Reproductive success (1 study): One replicated study in the South Atlantic Ocean found that most captive-reared Antillean manatees released back into the wild reproduced. Survival (11 studies): Three studies (including one replicated and controlled study) in the North Pacific Ocean, and the Indian River Lagoon found that a gray whale calf, three Steller sea lion pups, and a common bottlenose dolphin calf that were released after being reared in captivity survived during post-release monitoring periods of between three days to three months. Two replicated studies in the South Atlantic Ocean and water bodies in Florida found that approximately three-quarters of Antillean manatees and two-thirds of Florida manatees that were captive-reared and released were known to survive for at least one year, and some survived for more than seven years. Three studies in the North Atlantic Ocean, the North Pacific Ocean and the Guerrero Lagoon found that three West Indian manatee calves, seven Hawaiian monk seal pups and one Antillean manatee calf that were captive-reared either died before or after release, had to be returned to captivity after release, or survived in the wild only with supplemental feeding. Two studies at captive facilities found that a captive-reared grey whale calf and five pygmy and dwarf sperm whale calves increased in body weight but were either not released or died in captivity. One controlled study in the North Pacific Ocean found that captive-reared, released Pacific harbour seal pups had similar survival estimates to wild pups. BEHAVIOUR (3 STUDIES) Behaviour change (3 studies): Two controlled studies (including one replicated study) in the North Pacific Ocean found that captive-reared and released Pacific harbour seal pups and Steller sea lion pups had similar diving behaviour to wild pups. One controlled study in the Salish Sea found that captive-reared and released harbour seal pups travelled greater distances and further from the release site than wild pups born at the same site and in the same season. Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2926https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2926Tue, 09 Feb 2021 10:51:31 +0000
What Works 2021 cover

What Works in Conservation

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

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