Collected Evidence: Collected Evidence: Reduce capacity of cooling water intake structures We found no studies that evaluated the effects of reducing capacity of 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%2F2752https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2752Tue, 02 Feb 2021 16:54:58 +0000Collected Evidence: Collected Evidence: Reduce shipping along inland waterways We found no studies that evaluated the effects of reducing shipping along inland waterways 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%2F2763https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2763Tue, 02 Feb 2021 17:07:40 +0000Collected Evidence: Collected Evidence: Replace or repair damaged anti-predator nets around aquaculture systems One study evaluated the effects on marine mammals of replacing anti-predator nets around aquaculture systems. The study was in the North Atlantic Ocean (USA). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (0 STUDIES)       OTHER (1 STUDY) Human-wildlife conflict (1 study): One site comparison study in the North Atlantic Ocean found that replacing anti-predator nets more frequently at salmon farms resulted in fewer salmon losses to harbour seal predation. Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2774https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2774Thu, 04 Feb 2021 15:21:20 +0000Collected Evidence: Collected Evidence: Restrict capture of marine and freshwater mammals for research or aquariums and zoos We found no studies that evaluated the effects of restricting capture of marine and freshwater mammals for research or aquariums and zoos. ‘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%2F2782https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2782Thu, 04 Feb 2021 16:17:27 +0000Collected Evidence: Collected Evidence: Reduce duration of time fishing gear is in the water We found no studies that evaluated the effects of reducing the duration of time fishing gear is in the water 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%2F2796https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2796Thu, 04 Feb 2021 16:38:40 +0000Collected Evidence: Collected Evidence: Retain buoys and lines at the sea floor or river bed when not hauling We found no studies that evaluated the effects of retaining buoys and lines at the sea floor or river bed when not hauling 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%2F2798https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2798Thu, 04 Feb 2021 16:40:23 +0000Collected Evidence: Collected Evidence: Retain offal on fishing vessels instead of discarding overboard We found no studies that evaluated the effects of retaining offal on fishing vessels instead of discarding overboard 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%2F2827https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2827Fri, 05 Feb 2021 15:58:14 +0000Collected Evidence: Collected Evidence: Remove or clean-up oil pollution following a spill We found no studies that evaluated the effects of removing or cleaning up oil pollution following a spill 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%2F2870https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2870Mon, 08 Feb 2021 11:29:48 +0000Collected Evidence: Collected Evidence: Rehabilitate and release marine and freshwater mammals following oil spills We found no studies that evaluated the effects of rehabilitating and releasing marine and freshwater mammals following oil spills. ‘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%2F2871https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2871Mon, 08 Feb 2021 11:30:30 +0000Collected Evidence: Collected Evidence: Relocate marine and freshwater mammals following oil spills We found no studies that evaluated the effects of relocating marine and freshwater mammals following oil spills. ‘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%2F2872https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2872Mon, 08 Feb 2021 11:31:21 +0000Collected Evidence: Collected Evidence: Reduce the amount of pesticides used in aquaculture systems We found no studies that evaluated the effects of reducing the amount of pesticides used in aquaculture systems 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%2F2877https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2877Mon, 08 Feb 2021 11:42:45 +0000Collected Evidence: Collected Evidence: Reduce the amount of antibiotics used in aquaculture systems We found no studies that evaluated the effects of reducing the amount of antibiotics used in aquaculture systems 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%2F2878https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2878Mon, 08 Feb 2021 11:43:28 +0000Collected Evidence: Collected Evidence: Reduce pesticide, herbicide or fertilizer use We found no studies that evaluated the effects of reducing pesticide, herbicide or fertilizer use 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%2F2879https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2879Mon, 08 Feb 2021 11:44:13 +0000Collected Evidence: Collected Evidence: Recover lost or discarded fishing gear We found no studies that evaluated the effects of recovering lost or discarded 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%2F2886https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2886Mon, 08 Feb 2021 11:49:11 +0000Collected Evidence: Collected Evidence: Remove derelict fishing gear from mammals found entangled Two studies evaluated the effects of removing derelict fishing gear from mammals found entangled. One study was in the North Pacific Ocean (USA) and one in the North Atlantic Ocean (USA). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (2 STUDIES) Reproductive success (1 study): One review in the North Pacific Ocean found that after removing derelict fishing gear from Hawaiian monk seals, along with at least seven other interventions to enhance survival, more than a quarter of the seals reproduced. Survival (2 studies): One review in the North Pacific Ocean found that removing derelict fishing gear from Hawaiian monk seals, along with at least seven other interventions to enhance survival, resulted in more than a quarter of the seals surviving. One review in the North Atlantic Ocean found that three common bottlenose dolphins survived for at least 1–4 years after they were disentangled from derelict fishing gear and released. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2892https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2892Mon, 08 Feb 2021 11:56:01 +0000Collected Evidence: Collected Evidence: Remove litter from marine and freshwater environments We found no studies that evaluated the effects of removing litter from marine and freshwater environments 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%2F2895https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2895Mon, 08 Feb 2021 11:59:16 +0000Collected Evidence: Collected Evidence: Reduce hammer energy during pile driving We found no studies that evaluated the effects of reducing hammer energy during pile driving 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%2F2900https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2900Mon, 08 Feb 2021 16:10:51 +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: 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: 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: 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: Remove individual marine and freshwater mammals exhibiting aggressive behaviours that may limit population recovery One study evaluated the effects of removing individual marine mammals exhibiting aggressive behaviours that may limit population recovery. The study was in the North Pacific Ocean (USA). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Survival (1 study): One before-and-after study in the North Pacific Ocean found that after removing aggressive male Hawaiian monk seals, the survival of adult female Hawaiian monk seals increased. Condition (1 study): One before-and-after study in the North Pacific Ocean found that fewer female Hawaiian monk seals were injured after aggressive male Hawaiian monk seals were removed. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2929https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2929Tue, 09 Feb 2021 11:09:19 +0000Collected Evidence: Collected Evidence: Release captive-bred marine and freshwater mammals to re-establish or boost native populations Two studies evaluated the effects of releasing captive-bred marine and freshwater mammals to re-establish or boost native populations. One study was in the Porto de Pedras estuary (Brazil) and one in water bodies in Florida (USA). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (2 STUDIES) Survival (2 studies): Two studies in the Porto de Pedras estuary and water bodies in Florida found that two of three Antillean manatees and two of 14 Florida manatees born in captivity and released into the wild survived for at least one year without further intervention. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2933https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2933Tue, 09 Feb 2021 11:36:19 +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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