Collected Evidence: Collected Evidence: Designate a Marine Protected Area and prohibit aquaculture activity One study examined the effects of prohibiting aquaculture activity in a protected area on subtidal benthic invertebrate populations. The study was in Tapong Bay lagoon (Taiwan).   COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Crustacean abundance (1 study): One before-and-after study in Tapong Bay lagoon found that two and a half years after removing oyster aquaculture in a marine protected area, the biomasses of amphipods and shrimps had decreased, and that the biomass of crabs had not changed. Mollusc abundance (1 study): One before-and-after study in Tapong Bay lagoon found that two and a half years after removing oyster aquaculture in a marine protected area, the biomasses of gastropods and bivalves had decreased. Worm abundance (1 study): One before-and-after study in Tapong Bay lagoon found that two and a half years after removing oyster aquaculture in a marine protected area, the biomass of polychaete worms had stayed the same. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2240https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2240Wed, 23 Oct 2019 08:37:47 +0100Collected Evidence: Collected Evidence: Establish community-based fisheries management One study examined the effects of establishing community-based fisheries management on subtidal benthic invertebrate populations. The study was in the Foveaux Straight (New Zealand).   COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Mollusc abundance (1 study): One replicated, site comparison study in the Foveaux Straight found that a customary fisheries area where management was community-based had more New Zealand scallops compared to a protected area prohibiting all fishing and an area allowing recreational harvest. Mollusc condition (1 study): One replicated, site comparison study in the Foveaux Straight found that a customary fisheries area where management was community-based, tended to have smaller New Zealand scallops compared to a protected area prohibiting all fishing and an area allowing recreational harvest. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2242https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2242Wed, 23 Oct 2019 08:39:43 +0100Collected Evidence: Collected Evidence: Restore biogenic habitats (other methods) - Restore mussel beds Two studies examined the effects of restoring mussel beds (not by transplanting or translocating mussels) on mussels and mussel bed-associated subtidal benthic invertebrates. Both were in Strangford Lough (UK).   COMMUNITY RESPONSE (2 STUDIES) Overall community composition (2 studies): One replicated, controlled study in Strangford Lough found that after restoring beds of horse mussels by adding scallop shells to the seabed, overall invertebrate community composition in restored plots was different to that of unrestored plots. One replicated, controlled study in the same area found that after restoring beds of horse mussels by adding scallop shells to the seabed and translocating horse mussels, overall invertebrate community composition in plots restored with shells and mussels was different to plots restored without mussels (shells only), and both were different to unrestored plots and to nearby natural horse mussel beds. Overall species richness/diversity (2 studies): One replicated, controlled study in Strangford Lough found that after restoring beds of horse mussels by adding scallop shells to the seabed, overall invertebrate species diversity was lower in restored plots compared to unrestored plots, but species richness was similar. One replicated, controlled study in the same area found that after restoring beds of horse mussels by adding scallop shells to the seabed and translocating horse mussels, species richness and diversity were higher in restored plots with mussels and shells compared to plots with shells only, and similar to nearby natural horse mussel beds. POPULATION RESPONSE (1 STUDY) Overall abundance (1 study): One replicated, controlled study in Strangford Lough found that after restoring beds of horse mussels by adding scallop shells to the seabed, overall invertebrate abundance was higher in restored plots compared to unrestored plots. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2247https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2247Wed, 23 Oct 2019 09:33:18 +0100Collected Evidence: Collected Evidence: Refill disused borrow pits One study examined the effects of refilling disused borrow pits on subtidal benthic invertebrate populations. The study was in Barnegat Bay estuary (USA).   COMMUNITY RESPONSE (1 STUDY) Overall richness/diversity (1 study): One before-and-after, site comparison study in Barnegat Bay estuary found that overall invertebrate species richness and diversity increased at a disused borrow pit after being refilled with sediments but remained lower than at a natural non-dredged site. POPULATION RESPONSE (1 STUDY) Overall abundance (1 study): One before-and-after, site comparison study in Barnegat Bay estuary found that overall invertebrate abundance increased at a disused borrow pit after being refilled with sediments but remained lower than at a natural non-dredged site. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2251https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2251Wed, 23 Oct 2019 09:51:36 +0100Collected Evidence: Collected Evidence: Install a pump on or above the seabed in docks, ports, harbour, or other coastal areas to increase oxygen concentration One study examined the effects of installing a pump on or above the seabed in docks, ports, harbour, or other coastal areas to increase oxygen concentration on subtidal benthic invertebrate populations. The study was in Osaka Bay (Japan).   COMMUNITY RESPONSE (1 STUDY) Overall richness/diversity (1 study): One before-and-after study in Osaka Bay found that installing a pump on the seabed of a port to mix seawater and increase oxygen concentration led to an increase in combined invertebrate and fish species richness. POPULATION RESPONSE (1 STUDY) Overall abundance (1 study): One before-and-after study in Osaka Bay found that installing a pump on the seabed of a port to mix seawater and increase oxygen concentration led to an increase in combined invertebrates and fish abundance. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2252https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2252Wed, 23 Oct 2019 09:52:56 +0100Collected Evidence: Collected Evidence: Repurpose obsolete offshore structures to act as artificial reefs One study examined the effects of repurposing obsolete offshore structures on subtidal benthic invertebrates. The study was of a sunken oil rig in the Mediterranean Sea (Italy).   COMMUNITY RESPONSE (1 STUDY) Overall species richness/diversity (1 study): One study in the Mediterranean Sea recorded at least 53 invertebrate species having colonised a sunken oil rig after 30 years. Species included 14 species of molluscs, 14 species of worms, and 11 species of crustaceans. POPULATION RESPONSE (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2262https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2262Wed, 23 Oct 2019 10:57:16 +0100Collected Evidence: Collected Evidence: Remove and relocate habitat-forming (biogenic) species before onset of impactful activities One study examined the effects of removing and relocating habitat-forming species before onset of impactful activities on subtidal benthic invertebrates. The study was in the Fal Estuary (UK).   COMMUNITY RESPONSE (1 STUDY) Overall community composition (1 study): One replicated, paired, controlled study in the Fal Estuary found that invertebrate community composition was different in plots where maërl bed habitat had been removed and relayed compared to undisturbed maërl after five weeks, but similar after 44 weeks. Overall species richness/diversity (1 study): One replicated, paired, controlled study in the Fal Estuary found that invertebrate species richness was lower in plots where maërl bed habitat had been removed and relayed compared to undisturbed maërl after five weeks, but similar after 44 weeks. POPULATION RESPONSE (1 STUDY) Overall abundance (1 study): One replicated, paired, controlled study in the Fal Estuary found that invertebrate abundance was different in plots where maërl bed habitat had been removed and relayed compared to undisturbed maërl after five weeks, but similar after 44 weeks. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2264https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2264Wed, 23 Oct 2019 11:00:53 +0100Collected Evidence: Collected Evidence: Transplant/release captive-bred or hatchery-reared species in predator exclusion cages One study examined the effects of transplanting or releasing hatchery-reared species in predator exclusion cages on their wild populations. The study was in the North Pacific Ocean (Canada).   COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Survival (1 study): One replicated, controlled study the North Pacific Ocean found that hatchery-reared abalone transplanted in predator exclusion cages had similar survivorship following release compared to those transplanted directly onto the seabed. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2268https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2268Wed, 23 Oct 2019 12:32:51 +0100Collected Evidence: Collected Evidence: Translocate species - Translocate crustaceans One study examined the effects of translocating crustacean species on their wild populations. The study took place in the Tasman Sea (Australia).   COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Crustacean survival (1 study): One study in the Tasman Sea found that following translocation survival of southern rock lobsters was similar to that of resident lobsters. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2269https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2269Wed, 23 Oct 2019 12:36:49 +0100Collected Evidence: Collected Evidence: Translocate species - Translocate worms One study examined the effects of translocating worm species on their wild populations. The study was in Scottish Lochs (UK).   COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Worm survival (1 study): One replicated, controlled study in Scottish Lochs found that no reef-forming red tube worm survived when translocated to a new Loch, but survival was high when worms were translocated back to its source Loch. Worm condition (1 study): One replicated, controlled study in Scottish Lochs found that no reef-forming red tube worm survived and so no growth was recorded when translocated to a new loch, worms translocated back to its source Loch grew. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2271https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2271Wed, 23 Oct 2019 12:47:40 +0100Collected Evidence: Collected Evidence: Tag species to prevent illegal fishing or harvesting One study examined the effects of tagging species to prevent illegal fishing or harvesting on subtidal benthic invertebrates. The study examined the effects on the Californian abalone fishery (USA).   COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOURS (1 STUDY) Behaviour-change (1 study): One before-and-after study in California found no significant reduction in non-compliance with daily quotas of abalones after introducing tagging regulations. OTHER (1 STUDY) Illegal catch (1 study): One before-and-after study in California found no significant reduction in illegal takes of abalones after introducing tagging regulations. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2275https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2275Wed, 23 Oct 2019 12:50:46 +0100Collected Evidence: Collected Evidence: Provide educational or other training programmes about the marine environment to improve behaviours towards marine invertebrates One study examined the effects of providing educational or other training programmes about the marine environment on subtidal benthic invertebrate populations. The study took place in Hong Kong.   COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (1 STUDY) Behaviour change (1 study): One replicated, before-and-after survey study in Hong Kong found that a conservation education programme on the Asian horseshoe crab in secondary schools significantly increased the students’ behaviour towards Asian horseshoe crab conservation. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2281https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2281Wed, 23 Oct 2019 13:38:47 +0100Collected 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%2Fwww.conservationevidence.com%2Factions%2F2774https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2774Thu, 04 Feb 2021 15:21:20 +0000Collected Evidence: Collected Evidence: Establish ‘move-on rules’ for fishing vessels if mammals are encountered One study evaluated the effects on marine mammals of establishing move-on rules for fishing vessels if mammals are encountered. 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 measures to delay or relocate fishing if dolphins were encountered, along with releasing trapped dolphins, resulted in fewer short-beaked common dolphins being encircled and killed. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2790https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2790Thu, 04 Feb 2021 16:29:13 +0000Collected Evidence: Collected Evidence: Deploy fishing gear at different depths One study evaluated the effects on marine mammals of deploying fishing gear at different depths. The study was in the Arafura Sea (Australia). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (0 STUDIES) OTHER (1 STUDY) Reduction in entanglements/unwanted catch (1 study): One controlled study in the Arafura Sea found that fishing nets deployed 4.5 m below the water surface had fewer entanglements of dolphins than surface nets. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2793https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2793Thu, 04 Feb 2021 16:33:47 +0000Collected Evidence: Collected Evidence: Use stiffened materials or increase tension of fishing gear One study evaluated the effects on marine mammals of using stiffened materials in fishing nets. The study was in the South Atlantic Ocean (Argentina). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (0 STUDIES) OTHER (1 STUDY) Reduction in entanglements/unwanted catch (1 study): One controlled study in the South Atlantic Ocean found that using stiffened fishing nets did not reduce the number of Franciscana dolphin entanglements. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2801https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2801Thu, 04 Feb 2021 17:10:46 +0000Collected Evidence: Collected Evidence: Use a larger mesh size for fishing trap-nets One study evaluated the effects on freshwater mammals of using a larger mesh size for fishing trap-nets. The study was in the River Indal (Sweden). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (0 STUDIES) OTHER (1 STUDY) Human-wildlife conflict (1 study): One controlled study in the River Indal found that a fishing trap-net with a larger mesh size in the first two sections had fewer grey seals feeding around it and less damage caused by seals. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2803https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2803Thu, 04 Feb 2021 17:13:38 +0000Collected Evidence: Collected Evidence: Play predator calls to deter mammals from fishing gear One study evaluated the effects of playing predator calls to deter mammals from fishing gear. The study was in the South Atlantic Ocean (Africa). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (0 STUDIES) OTHER (1 STUDY) Human-wildlife conflict (1 study): One study in the South Atlantic Ocean found that playing killer whale vocalisations did not deter Cape fur seals from feeding on fish catches in a purse-seine net or trawl net. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2817https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2817Fri, 05 Feb 2021 15:08:39 +0000Collected Evidence: Collected Evidence: Use an electric current to deter mammals from fishing gear One study evaluated the effects of using an electric current to deter mammals from fishing gear. The study was in the Fraser River (Canada). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (0 STUDIES) OTHER (1 STUDY) Human-wildlife conflict (1 study): One controlled study in the Fraser River found that using an electric current on a fishing net reduced Pacific harbour seal predation on salmon catches. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2818https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2818Fri, 05 Feb 2021 15:10:45 +0000Collected Evidence: Collected Evidence: Use noise aversive conditioning to deter mammals from fishing gear One study evaluated the effects on marine mammals of using noise aversive conditioning to deter mammals from fishing gear. The study was in the North Pacific Ocean (USA). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (0 STUDIES) OTHER (1 STUDY) Human-wildlife conflict (1 study): One study in the North Pacific Ocean found that noise aversive conditioning did not reduce bait foraging behaviour by California sea lions. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2819https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2819Fri, 05 Feb 2021 15:12:55 +0000Collected Evidence: Collected Evidence: Use acoustic decoys to divert mammals away from fishing gear One study evaluated the effects on marine mammals of using acoustic decoys to divert mammals away from fishing gear. The study was in the Gulf of Alaska (USA). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (1 STUDY) Behaviour change (1 study): One study in the Gulf of Alaska found that increasing the distance between an acoustic decoy device and fishing lines resulted in fewer sperm whales at the lines, but sperm whale presence and time of arrival did not differ. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2820https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2820Fri, 05 Feb 2021 15:15:05 +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%2Fwww.conservationevidence.com%2Factions%2F2824https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2824Fri, 05 Feb 2021 15:52:33 +0000Collected Evidence: Collected Evidence: Switch off artificial lighting at wild fisheries One study evaluated the effects on freshwater mammals of switching off artificial lights 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 switching off artificial lights on a bridge did not deter harbour seals from feeding on salmon released from a hatchery. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2825https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2825Fri, 05 Feb 2021 15:56:10 +0000Collected Evidence: Collected Evidence: Use ‘mammal-safe’ nets to capture and release mammals trapped in fishing structures One study evaluated the effects on marine mammals of using ‘mammal-safe’ nets to capture and release mammals trapped in fishing structures. The study was in the Bay of Fundy (Canada). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Survival (1 study): One controlled study in the Bay of Fundy found that using ‘marine mammal nets’ with a larger mesh size to release harbour porpoises from herring weirs resulted in lower porpoise mortality compared to using conventional herring nets. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2828https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2828Fri, 05 Feb 2021 16:00:21 +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%2Fwww.conservationevidence.com%2Factions%2F2829https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2829Fri, 05 Feb 2021 16:02:48 +0000
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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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