Collected Evidence: Collected Evidence: Limit, cease or prohibit the use of underwater explosives We found no studies that evaluated the effects of limiting, ceasing or prohibiting the use of underwater explosives 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%2F2903https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2903Mon, 08 Feb 2021 16:14:39 +0000Collected Evidence: Collected Evidence: Modify vessels to reduce noise disturbance We found no studies that evaluated the effects of modifying vessels to reduce noise disturbance 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%2F2904https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2904Mon, 08 Feb 2021 16:15:34 +0000Collected Evidence: Collected Evidence: Limit, cease or prohibit the discharge of cooling effluents from power stations We found no studies that evaluated the effects of limiting, ceasing or prohibiting the discharge of cooling effluents from power stations 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%2F2905https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2905Mon, 08 Feb 2021 16:16:15 +0000Collected Evidence: Collected Evidence: Use methods to reduce sediment disturbance during dredging (e.g. curtains, screens) We found no studies that evaluated the effects of using methods to reduce sediment disturbance during dredging, 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%2F2906https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2906Mon, 08 Feb 2021 16:17:21 +0000Collected Evidence: Collected Evidence: Limit, cease or prohibit discharge of waste effluents overboard from vessels We found no studies that evaluated the effects of limiting, ceasing or prohibiting discharge of waste effluents overboard from vessels, 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%2F2907https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2907Mon, 08 Feb 2021 16:18:11 +0000Collected Evidence: Collected Evidence: Use non-toxic antifouling coatings on surfaces We found no studies that evaluated the effects of using non-toxic antifouling coatings on surfaces, 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%2F2908https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2908Mon, 08 Feb 2021 16:19:22 +0000Collected Evidence: Collected Evidence: Remove and clean-up shoreline waste disposal sites We found no studies that evaluated the effects of removing and cleaning up shoreline waste disposal sites 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%2F2909https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2909Mon, 08 Feb 2021 16:19:56 +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: Legally protect areas where climate change impacts are predicted to be less severe We found no studies that evaluated the effects of legally protecting areas where climate change impacts are predicted to be less severe 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%2F2912https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2912Mon, 08 Feb 2021 16:22:44 +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: Manage water levels and flow in rivers to maintain deep pools and connectivity We found no studies that evaluated the effects of managing water levels and flow in rivers to maintain deep pools and connectivity on 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%2F2914https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2914Mon, 08 Feb 2021 16:24:21 +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%2Fconservationevidencejournal.com%2Factions%2F2915https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2915Mon, 08 Feb 2021 16:29:11 +0000Collected Evidence: Collected Evidence: Enforce existing legislation for habitat protection We found no studies that evaluated the effects of enforcing existing legislation for habitat protection 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%2F2916https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2916Mon, 08 Feb 2021 16:30:18 +0000Collected Evidence: Collected Evidence: Cease or prohibit activities that cause disturbance in sensitive areas for marine and freshwater mammals Two studies evaluated the effects of prohibiting activities that cause disturbance in sensitive areas for marine mammals. One study was in the Kattegat Sea (Denmark) and one in the Indian Ocean (Australia). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Abundance (1 study): One before-and-after study in the Kattegat sea found that harbour porpoise activity increased at a stony reef after fishing was prohibited and the reef was restored with boulders. BEHAVIOUR (1 STUDY) Behaviour change (1 study): One site comparison study in the Indian Ocean found that a beach where human access was fully prohibited had fewer Australian sea lions showing aggression or retreating compared to a beach where access was partly prohibited. Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2917https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2917Mon, 08 Feb 2021 16:33:04 +0000Collected Evidence: Collected Evidence: Cease or prohibit activities that cause disturbance during sensitive periods for marine and freshwater mammals We found no studies that evaluated the effects of ceasing or prohibiting activities that cause disturbance during sensitive periods for 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%2F2918https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2918Mon, 08 Feb 2021 16:34:09 +0000Collected Evidence: Collected Evidence: Retain or create buffer zones around important habitats We found no studies that evaluated the effects of retaining or creating buffer zones around important habitats 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%2F2919https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2919Mon, 08 Feb 2021 16:34:46 +0000Collected Evidence: Collected Evidence: Restore habitat for marine and freshwater mammals One study evaluated the effects of restoring habitat for marine mammals. The study was in the Kattegat sea (Denmark). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Abundance (1 study): One before-and-after study in the Kattegat sea found that harbour porpoise activity increased at a stony reef after it was restored with boulders and fishing was prohibited. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2920https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2920Mon, 08 Feb 2021 16:36:03 +0000Collected Evidence: Collected Evidence: Create artificial habitat for marine and freshwater mammals We found no studies that evaluated the effects of creating artificial habitat for 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%2F2921https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2921Mon, 08 Feb 2021 16:36:58 +0000Collected Evidence: Collected Evidence: Leave anthropogenic structures in place after decommissioning We found no studies that evaluated the effects of leaving anthropogenic structures in place after decommissioning 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%2F2922https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2922Mon, 08 Feb 2021 16:37:41 +0000Collected Evidence: Collected Evidence: Legally protect marine and freshwater mammal species We found no studies that evaluated the effects of legally protecting marine and freshwater mammal species. ‘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%2F2923https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2923Mon, 08 Feb 2021 16:38:46 +0000Collected Evidence: Collected Evidence: Rescue and release stranded or trapped marine and freshwater mammals Eleven studies evaluated the effects of rescuing and releasing stranded or trapped marine and freshwater mammals. Five studies were in the North Atlantic Ocean (USA), two studies were in the Indian Ocean (Tasmania, South Africa), and one study was in each of the South Atlantic Ocean (Brazil), the Cachoeira River estuary (Brazil), the North Pacific Ocean (USA) and the Shannon Estuary (Ireland). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (11 STUDIES) Reproductive success (2 studies): One review in the North Pacific Ocean found that after rescuing and releasing stranded or trapped Hawaiian monk seals, along with at least seven other interventions to enhance survival, more than a quarter of the seals reproduced. One study in the Shannon Estuary found that a stranded common bottlenose dolphin that was rescued and released was observed with a calf a year later. Survival (11 studies): Seven studies (including one review) in the North Atlantic Ocean, Indian Ocean and the Shannon Estuary found that 17–100% of rescued and released Atlantic white-sided dolphins, short-beaked common dolphins, common bottlenose dolphins, long-finned pilot whales, short-finned pilot whales, and Cape fur seals survived during post-release monitoring periods, which ranged in length from three weeks to three years. Three studies in the South Atlantic Ocean, the Cachoeira estuary and the Indian Ocean found that a trapped rough-toothed dolphin, two stranded tucuxi dolphins and seven stranded sperm whales were successfully rescued and released, although long-term survival was not reported. One review in the North Pacific Ocean found that rescuing and releasing stranded or trapped Hawaiian monk seals, along with at least seven other interventions to enhance survival, resulted in more than a quarter of the seals surviving. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2924https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2924Mon, 08 Feb 2021 16:51:49 +0000Collected Evidence: Collected Evidence: Rehabilitate and release injured, sick or weak marine and freshwater mammals Twenty-seven studies evaluated the effects of rehabilitating and releasing injured, sick or weak marine and freshwater mammals. Nine studies were in the North Atlantic Ocean (USA, UK, France), six studies were in the North Pacific Ocean (USA), four studies were in the Gulf of Mexico (USA), two studies were in each of the North Sea (the Netherlands) and the Gulf of Maine (USA), and one study was in each of the Indian River Lagoon (USA), Bohai Bay (China), The Wash estuary (UK), water bodies in Florida (USA), El Dorado Lake (Peru), and the Gulf of California (Mexico). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (26 STUDIES) Reproductive success (1 study): One replicated study in the North Pacific Ocean found that more than a quarter of rehabilitated and released Hawaiian monk seals reproduced. Survival (26 studies): Twenty-one studies (including two controlled studies, four replicated studies and one review) in the North Atlantic Ocean, the Gulf of Maine, the Gulf of Mexico, the North Pacific Ocean, the Indian River Lagoon, The Wash estuary, water bodies in Florida, El Dorado Lake, and the Gulf of California found that 10–100% of dolphins, porpoises, whales, seals, sea lions and manatees released after rehabilitation in captivity survived during post-release monitoring periods, which ranged in length from three days to five years. Five studies (including one replicated study) in the North Sea, the North Atlantic Ocean, Bohai Bay and the North Pacific Ocean found that two of three harbour porpoises, 152 of 188 grey seal pups, a common seal, a west Pacific finless porpoise and 14 of 35 California sea lions were successfully rehabilitated and released but survival after release was not reported. One controlled study in the North Pacific Ocean found that at least a quarter of California sea lions treated for toxic algae poisoning and released back into the wild died or had to be euthanized. BEHAVIOUR (3 STUDIES) Behaviour change (3 studies): Two of three controlled studies in the North Atlantic Ocean, the North Pacific Ocean and The Wash estuary found that a harbour porpoise and six harbour seals that were rehabilitated and released had similar movements and/or behaviours to wild mammals. The other study found that California sea lions treated for toxic algae poisoning and released travelled further from the shore, spent less time diving or hauled out and made shorter, shallower dives than wild sea lions without poisoning. Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2925https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2925Mon, 08 Feb 2021 16:57:11 +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 +0000Collected Evidence: Collected Evidence: Reunite abandoned marine and freshwater mammal young with parents One study evaluated the effects of reuniting abandoned marine and freshwater mammal young with parents. The study was in the North Pacific Ocean (USA). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Reproductive success (1 study): One review in the North Pacific Ocean found that after reuniting Hawaiian monk seal pups with their mothers, along with at least seven other interventions to enhance survival, more than a quarter of the seals reproduced. Survival (1 study): One review in the North Pacific Ocean found that after reuniting Hawaiian monk seal pups with their mothers, along with at least seven other interventions to enhance survival, more than a quarter of the seals survived. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2927https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2927Tue, 09 Feb 2021 11:06:36 +0000Collected Evidence: Collected Evidence: Place orphaned or abandoned marine and freshwater mammal young with foster parents We found no studies that evaluated the effects of placing orphaned or abandoned marine and freshwater mammal young with foster parents. ‘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%2F2928https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2928Tue, 09 Feb 2021 11:07:43 +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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