Collected Evidence: Collected Evidence: Translocate habitat-forming (biogenic) species - Translocate reef- or bed-forming molluscs Two studies examined the effects of translocating habitat-forming molluscs on associated subtidal benthic invertebrate populations. Both were in Strangford Lough (UK).   COMMUNITY RESPONSE (2 STUDIES) Overall community composition (2 studies): One replicated, site comparison study in Strangford Lough found that plots with translocated mussels had different associated invertebrate communities to plots without mussels, but also to natural mussel beds. One replicated, controlled study in Strangford Lough found that translocating mussels onto scallop shells or directly onto the seabed led to similar associated invertebrate communities. Overall richness/diversity (2 studies): One replicated, site comparison study in Strangford Lough found that plots with translocated mussels had higher richness and diversity of associated invertebrates to plots without mussels, and similar to natural mussel beds. One replicated, controlled study in Strangford Lough found that translocating mussels onto scallop shells or directly onto the seabed led to similar richness and diversity of associated invertebrates. POPULATION RESPONSE (2 STUDIES) Overall abundance (2 studies): One replicated, site comparison study in Strangford Lough presented unclear abundance results. One replicated, controlled study in Strangford Lough found that translocating mussels onto scallop shells or directly onto the seabed led to higher abundance of associated invertebrates in one of two comparisons. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2245https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2245Wed, 23 Oct 2019 08:48:18 +0100Collected Evidence: Collected Evidence: Translocate habitat-forming (biogenic) species - Translocate reef-forming corals Two studies examined the effects of translocating habitat-forming corals on associated subtidal benthic invertebrate populations. One was in Tayabas Bay (Philippines) and one in the South China Sea (Philippines).   COMMUNITY RESPONSE (2 STUDIES) Overall community composition (1 study): One replicated, controlled, before-and-after study in the South China Sea found that following coral translocation associated invertebrate communities did not change and remained similar to plots without translocated corals. Overall richness/diversity (2 studies): One replicated, controlled, before-and-after study in the South China Sea found that following coral translocation richness of associated invertebrates increased but also increased in plots without corals, likely due to spill-over. One replicated, controlled study in Tayabas Bay found that richness of associated invertebrates was higher in plots with translocated corals than in plots without. POPULATION RESPONSE (1 STUDY) Overall abundance (1 study): One replicated, controlled, before-and-after study in the South China Sea found that following coral translocation abundance of associated invertebrates increased and became higher than in plots without translocated corals. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2246https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2246Wed, 23 Oct 2019 08:52:10 +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: Restore biogenic habitats (other methods) - Restore oyster reefs Eight studies examined the effects of restoring oyster reefs (not by transplanting or translocating oysters) on oysters and oyster reef-associated subtidal benthic invertebrates. Two were in the Gulf of Mexico (USA), one was a global review, four were in the North Pacific Ocean (USA), and one was in the Mission-Aransas estuary (USA).   COMMUNITY RESPONSE (3 STUDIES) Overall community composition (2 studies): One of two replicated, controlled studies in the Gulf of Mexico and the Mission-Aransas estuary found that after restoring eastern oyster reefs, the community composition of combined mobile decapod invertebrates and fish was similar on all types of restoration material used, but the other found that composition varied with the material used. Overall species richness/diversity (3 studies): One replicated, site comparison study in the Gulf of Mexico found that diversity of reef-associated invertebrates was similar in reefs restored by laying rocks regardless of age, in young reefs restored by laying oyster shells, and in natural reefs, but lower in old shell-restored reefs. One replicated, controlled study in the Gulf of Mexico found that diversity of reef-associated invertebrates was higher in all restored reefs than on unrestored sediment, but that diversity varied between the restoration materials used. One replicated, controlled study in the Mission-Aransas estuary found that diversity of fish, crabs and shrimps varied with the restoration material used. POPULATION RESPONSE (7 STUDIES) Overall abundance (2 studies): One replicated, site comparison study in the Gulf of Mexico found that the effect of restoring eastern oyster reefs on the abundance of reef-associated invertebrates depended on the material used for restoration and the age of the reef. One replicated, controlled study in the Gulf of Mexico found that abundance of combined reef-associated mobile decapod invertebrate and fish was similar on all restored reefs regardless of the restoration material used, and higher than on unrestored sediment. Crustacean abundance (1 study): One replicated, controlled study in the Mission-Aransas estuary found that after restoring eastern oyster reefs, crab abundance, but not biomass, and shrimp biomass, but not abundance, varied with the restoration material used. Oyster abundance (6 studies): One replicated, site comparison study in the Gulf of Mexico found that oyster reefs restored by laying rocks had similar oyster abundance to natural reefs, and higher than reefs restored by laying oyster shells. One replicated, controlled study in the Mission-Aransas estuary found that oyster cover and abundance varied with the restoration material used. One replicated, controlled study in the Gulf of Mexico found that oyster spat abundance was similar on all types of restoration material used, and higher than on unrestored sediment. Three replicated, controlled studies in the North Pacific Ocean found that restoring oyster reefs by placing lines of clam shells below Mean Lower Low Water (MLLW) led to higher cover of clam shells by oysters than when placing the lines above MLLW, that for those placed below MLLW, keeping them there led to similar cover compared to moving them above MLLW halfway through the study, and that placing the lines on cobbly seabed led to similar cover compared to placing them on muddy seabed. Oyster reproductive success (3 studies): Three replicated, controlled studies in the North Pacific Ocean found that restoring oyster reefs by placing lines of clam shells below Mean Lower Low Water (MLLW) led to higher recruitment of oyster spat on clam shells than by lacing lines above MLLW, that recruitment was higher on lines placed on cobbly seabed than on muddy seabed, and that recruitment was similar on lines placed near or far from the nearest adult oyster populations. Oyster survival (5 studies): One global systematic review found that two of nine restoration techniques (restoring oyster reef by transplanting juveniles, and by creating no-harvest sanctuaries) assessed resulted in over 85% survival of restored oysters. Four replicated, controlled studies in the North Pacific Ocean found that restoring oyster reefs by placing lines of clam shells below Mean Lower Low Water (MLLW) led to similar survival of oysters than when placing the lines above MLLW, but that for those placed below MLLW, moving them above MLLW halfway through the study led to higher survival than keeping then below, that survival was similar on lines placed on cobbly seabed or muddy seabed, and that survival was similar on lines placed near or far from the nearest adult oyster populations. Oyster condition (5 studies): One replicated, controlled study in the Gulf of Mexico found that the effect of restoring eastern oyster reefs on average spat size varied with the restoration material used. One replicated, controlled study in the North Pacific Ocean found that restoring oyster reefs by placing lines of clam shells below Mean Lower Low Water (MLLW) led to similar growth of oysters on the shells than placing lines above MLLW. Four replicated, controlled studies in the North Pacific Ocean found that restoring oyster reefs by placing lines of clam shells below Mean Lower Low Water (MLLW) led to higher cover of clam shells by non-native species than placing lines above MLLW, but that for those placed below MLLW, moving them above MLLW halfway through the study led to lower cover than keeping then below, that cover was similar on lines placed on cobbly seabed or muddy seabed, and that cover of clam shells by non-native species was higher on lines placed near compared to far from the nearest adult oyster populations. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2248https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2248Wed, 23 Oct 2019 09:37:47 +0100Collected Evidence: Collected Evidence: Restore biogenic habitats (other methods) - Restore seagrass beds/meadows Three studies examined the effects of restoring seagrass beds (not by transplanting or translocating seagrass) on seagrass bed-associated subtidal benthic invertebrates. One was in the North Atlantic Ocean (USA), one in the Indian Ocean (Kenya), and one in the Florida Keys (USA).   COMMUNITY RESPONSE (2 STUDIES) Overall community composition (1 study): One randomized, replicated, controlled study in the Florida Keys found that restoring seagrass beds by fertilizing the seabed had no effect on overall invertebrate community composition, but adding sand led to communities different from both unrestored and natural sites. Overall species richness/diversity (2 studies): One randomized, replicated, controlled study in the Florida Keys found that after restoring seagrass beds by fertilizing the seabed and adding sand, overall invertebrate species richness was similar at restored, unrestored, and natural sites. One replicated, controlled study in the Indian Ocean found that transplanting plastic seagrass mimics into bare sites, previously-restored seagrass sites, and natural seagrass sites, resulted in similar invertebrate diversity on mimic leaves and in the surrounding sediment, and similar species richness on mimic leaves at all restored sites as on natural seagrass leaves. POPULATION RESPONSE (3 STUDIES) Overall abundance (3 studies): One replicated, randomized, controlled, before-and-after study in the North Atlantic Ocean found that after restoring seagrass beds, the abundance of mobile invertebrates had increased and was higher in restored than unrestored plots, but the abundance of sessile invertebrates had not increased. One replicated, controlled study in the Indian Ocean found that transplanting plastic seagrass mimics into bare sites, previously-restored seagrass sites, and natural seagrass sites, resulted in similar abundance of invertebrate in the surrounding sediment across sites, and resulted in different abundance of invertebrates on mimic leaves between sites although all had lower abundances than on natural seagrass leaves. One randomized, replicated, controlled study in the Florida Keys found that after restoring seagrass beds by fertilizing the seabed or adding sand, overall invertebrate abundance was not different at restored sites compared to both unrestored and natural sites. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2249https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2249Wed, 23 Oct 2019 09:45:10 +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: Landscape or artificially enhance the seabed (natural habitats) Three studies examined the effects of landscaping or artificially enhancing the seabed on subtidal benthic invertebrates. One study was in the North Sea (UK), one in the Westerschelde estuary (Netherlands), and one in the Persian Gulf (Kuwait).   COMMUNITY RESPONSE (3 STUDIES) Overall community composition (2 studies): One controlled, before-and after study in the North Sea found that following addition of gravels, invertebrate community composition became more similar to natural seabed communities. One before-and-after, site comparison study in the Westerschelde estuary found no change in invertebrate community composition following addition of sedimentary dredge material. Overall richness/diversity (3 studies): One controlled, before-and after study in the North Sea and one site comparison study in the Persian Gulf found that invertebrate species richness increased following addition of gravels or coral and limestone rubbles, and one also found that richness became similar to natural seabed. One before-and-after, site comparison study in the Westerschelde estuary found no change in species richness following addition of sedimentary dredged material. POPULATION RESPONSE (3 STUDIES) Overall abundance (3 studies): One controlled, before-and after study in the North Sea and one site comparison study in the Persian Gulf found that invertebrate abundance and biomass increased following addition of gravels or coral and limestone rubbles, and one also found that abundance became similar to natural seabed. One before-and-after, site comparison study in the Westerschelde estuary found no change in invertebrate abundance and biomass following addition of sedimentary dredge material. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2253https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2253Wed, 23 Oct 2019 09:56:38 +0100Collected Evidence: Collected Evidence: Provide artificial shelters Five studies examined the effects of providing artificial shelters on subtidal benthic invertebrates. Three studies were in the Caribbean Sea (Mexico); one in Florida Bay and one in the Florida Keys (USA).   COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (2 STUDIES) Lobster abundance (2 studies): Two replicated, controlled, before-and-after studies in the Caribbean Sea found that abundance of lobsters either increased in plots with artificial shelters but not in plots without, or increased in all plots but more so in plots with artificial shelters than those without. Lobster condition (1 study): One replicated, controlled, before-and-after study in the Caribbean Sea found that lobsters in plots with artificial shelters were bigger than in plots without. BEHAVIOUR (3 STUDIES) Use (3 studies): Three replicated studies (two controlled) in Florida Bay, the Florida Keys, and the Caribbean Sea, found that artificial shelters were occupied by lobsters and molluscs, that occupancy by lobsters varied with artificial shelter designs, that lobsters occupied artificial shelters more than natural ones (crevices), and that lobsters occupying artificial shelters were larger, had greater nutritional condition, and had similar sex ratio and survival rate, compared to lobsters occupying natural shelters. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2257https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2257Wed, 23 Oct 2019 10:13:10 +0100Collected Evidence: Collected Evidence: Create artificial reefs Twelve studies examined the effects of creating artificial reefs on subtidal benthic invertebrate populations. Three studies were in the Mediterranean Sea (Italy); three were in the North Atlantic Ocean (USA, Portugal, France); one in the Firth of Lorn (UK); two in the North Pacific Ocean (USA); one in the English Channel (UK), one in the Gulf of Mexico (USA); and one in the Yellow Sea (China).   COMMUNITY RESPONSE (8 STUDIES) Overall community composition (3 studies): Two site comparison studies (one replicated) in the English Channel and North Atlantic Ocean found that invertebrate communities growing on artificial reefs were different to that of natural reefs. One replicated study the North Pacific Ocean found that invertebrate community composition changed over time on an artificial reef. Overall richness/diversity (6 studies): Two site comparison studies (one replicated) in the Mediterranean Sea and North Atlantic Ocean found that invertebrate species richness and/or diversity on the artificial reef or in the sediments inside and adjacent to the reef area were lower compared to on natural reefs or in nearby natural sediments. One replicated, site comparison study in the Gulf of Mexico found that artificial breakwaters had more species of nekton compared to adjacent mudflats. One site comparison study in English Channel recorded 263 taxa on the artificial reef, including at least nine not recorded on nearby natural reefs but excluding at least 39 recorded on natural reefs. One replicated study in the North Pacific Ocean found a 49% increase in species richness over five years on an artificial reef. One study in the North Atlantic Ocean found that artificial reefs hosted at least five species of large mobile invertebrates. Mollusc richness/diversity (1 study): One replicated, site comparison study in the Mediterranean Sea found that mollusc species richness and diversity were lower on artificial reefs compared to natural reefs. Worm community composition (1 study): One replicated, site comparison study in the North Pacific Ocean found that polychaete worm community composition was similar at one of two artificial reefs compared to a natural reef. Worm richness/diversity (1 study): One replicated, site comparison study in the North Pacific Ocean found that polychaete worm species richness and diversity were similar at one of two artificial reefs compared to a natural reef, but lower at the second artificial reef. POPULATION RESPONSE (12 STUDIES) Overall abundance (10 studies): One of two site comparison studies (one replicated) in the Mediterranean Sea found that abundance of invertebrates in the sediment was lower at the reef sites than in nearby natural sediments, but increased in the sediments directly adjacent to the reefs, while the other study found that abundance was similar in the sediments inside and directly adjacent to the artificial reef area, but lower than in nearby natural sediments. Of five site comparison studies (four replicated) in the North Pacific Ocean, the North Atlantic Ocean, the Gulf of Mexico and the Yellow Sea, one found that invertebrate biomass was higher on the artificial reef than in adjacent natural sediments, two that invertebrate abundance and biomass and nekton abundance were similar on artificial reefs and natural habitats (reef; mudflat), and two found mixed effects on abundances of invertebrates. One site comparison study in the English Channel reported that the abundances of some species were lower on the artificial reef compared to natural reefs. One replicated study in the North Pacific Ocean reported an 86% increase in invertebrate abundance growing on an artificial reef over five years. One study in the North Atlantic Ocean found that two of five species at one artificial reef, and three of seven at another, were recorded during >50% of dives. Overall condition (1 study): One replicated, site comparison study in the Yellow Sea found mixed effects of creating an artificial reef on the sizes of mobile invertebrates. Mollusc abundance (1 study): One replicated, site comparison study in the Mediterranean Sea found that mollusc abundance was lower on artificial reefs compared to natural reefs. Crustacean abundance (1 study): One replicated, site comparison in the Firth of Lorn found that abundances of edible crabs and velvet swimming crabs were typically higher on artificial than natural reefs. OTHER (1 STUDY) Biological production (1 study): One site comparison study in North Atlantic Ocean found that secondary production was higher from invertebrates growing on an artificial reef than from invertebrates in adjacent natural sediments. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2258https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2258Wed, 23 Oct 2019 10:26:30 +0100Collected Evidence: Collected Evidence: Create artificial reefs of different 3-D structure and material used Eight studies examined the effects of creating artificial reefs of different typology on subtidal benthic invertebrate populations. One study was in the English Channel (UK), three in the Mediterranean Sea (Israel, Italy), one in the North Atlantic Ocean (USA), one in the Firth of Lorn (UK), one in the North Pacific Ocean (USA), and one in the Gulf of Mexico (USA).   COMMUNITY RESPONSE (6 STUDIES) Overall community composition (3 studies): One controlled study in the English Channel found that artificial reef modules made of scrap tyres developed a similar sessile invertebrate community composition as traditional artificial concrete modules. Two controlled studies (one replicated) in the Mediterranean Sea found that pyramids reefs made of “sea-friendly” concrete developed different invertebrate community compositions compared to reefs of either traditional concrete plinth-pole structures or bundles of traditional concrete tubes. Overall richness/diversity (5 studies): Four controlled studies (three replicated) in the Mediterranean Sea, the North Pacific Ocean, and the Gulf of Mexico found no differences in overall invertebrate richness/diversity or combined mobile invertebrate and fish richness between reef structure and/or material. One controlled study in the Mediterranean Sea found that invertebrate species richness was lower on “sea-friendly” pyramid reefs compared to bundle reefs of traditional concrete. POPULATION RESPONSE (7 STUDIES) Overall abundance (5 studies): Four controlled studies (three replicated) in the English Channel, the Mediterranean Sea, the North Pacific Ocean, and the Gulf of Mexico found no differences in overall invertebrate abundances or combined mobile invertebrate and fish abundance between reef structure and/or material. One controlled study in the Mediterranean Sea found that “sea-friendly” concrete pyramids had lower abundance compared to plinth-pole structures after two years, but higher after three. Crustacean abundance (2 studies): One replicated, controlled study in the North Atlantic Ocean found that artificial reefs made of limestone boulders, gravel concrete aggregate, or tyre-concrete aggregate had similar abundance of spiny lobsters. One replicated, controlled study in the Firth of Lorn found that the complexity of artificial reef modules had mixed effects on the abundance of edible crab and velvet swimming crab. Mollusc abundance (1 study): One replicated, controlled study in the Gulf of Mexico found that breakwaters made of bags of oyster shells recruited more oysters and ribbed mussels compared to “ReefBall” breakwaters. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2259https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2259Wed, 23 Oct 2019 10:39:51 +0100Collected Evidence: Collected Evidence: Locate artificial reefs near aquaculture systems to benefit from nutrient run-offs Two studies examined the effects of locating artificial reefs near aquaculture systems to benefit from nutrient run-offs on subtidal benthic invertebrate populations. One study was in the Gulf of Aqaba (Israel and Jordan), and one in the Mediterranean Sea (Spain).   COMMUNITY RESPONSE (1 STUDY) Overall community composition (1 study): One controlled study in the Mediterranean Sea found that an artificial reef located under aquaculture cages had similar invertebrate community composition to artificial reefs located at sites without aquaculture cages. POPULATION RESPONSE (1 STUDY) Overall abundance (1 study): One controlled study in the Gulf of Aqaba found that an artificial reef located at an aquaculture site had similar invertebrate biomass growing on it compared to an artificial reef located at a site without aquaculture cages. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2260https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2260Wed, 23 Oct 2019 10:51:01 +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: Offset habitat loss from human activity by restoring or creating habitats elsewhere Two studies examined the effects of offsetting habitat loss from human activity by restoring or creating habitats elsewhere on subtidal benthic invertebrate populations. One study was in the Delaware Bay (USA), the other in the Persian Gulf (Kuwait).   COMMUNITY RESPONSE (1 STUDY) Overall richness/diversity (1 study): One study in the Persian Gulf found that an area of low ecological value restored to offset habitat lost to land reclamation was colonized by over 198 invertebrate species. POPULATION RESPONSE (0 STUDIES) OTHER (1 STUDY) Biological production (1 study): One study in Delaware Bay found that an artificial reef built to offset lost soft-sediment habitat had higher annual secondary production/unit area from sessile invertebrates, but lower total annual secondary production, compared to habitat similar to that lost. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2265https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2265Wed, 23 Oct 2019 11:03:46 +0100Collected Evidence: Collected Evidence: Transplant/release captive-bred or hatchery-reared species - Transplant/release crustaceans Five studies examined the effects of transplanting or releasing hatchery-reared crustacean species on their wild populations. Four examined lobsters in the North Sea (Germany, Norway, UK), and one examined prawns in the Swan-Canning Estuary (Australia).   COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (5 STUDIES) Crustacean abundance (1 study): One study in the Swan-Canning Estuary  found that after releasing hatchery-reared prawn larvae into the wild, the abundance of egg-bearing female prawns increased. Crustacean reproductive success (3 studies): Two studies (one controlled) in the North Sea found that after their release, recaptured hatchery-reared female lobsters carried eggs, and the number, size and developmental stage of eggs were similar to that of wild females. One study in the Swan-Canning Estuary  found that after releasing hatchery-reared prawn larvae into the wild the overall population fecundity (egg production/area) increased. Crustacean survival (2 studies): Two studies in the North Sea found that 50–84% and 32–39% of hatchery-reared lobsters survived in the wild after release, up to eight and up to five years, respectively. Crustacean condition (4 studies): Two studies in the North Sea found that hatchery-reared lobsters grew in the wild after release. One controlled study in the North Sea found that after release into the wild, hatchery-reared female lobsters had similar growth rates as wild females. One study in the North Sea found that after releasing hatchery-reared lobsters, no recaptured lobsters displayed signs of “Black Spot” disease, and 95% had developed a crusher-claw. One study in the Swan-Canning Estuary  found that after releasing hatchery-reared prawn larvae into the wild, the size of egg-bearing female prawns increased. BEHAVIOUR (1 STUDY) Crustacean movement (1 study): One controlled study in the North Sea found that after release into the wild, hatchery-reared female lobsters had similar movement patterns as wild females. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2266https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2266Wed, 23 Oct 2019 12:11:24 +0100Collected Evidence: Collected Evidence: Transplant/release captive-bred or hatchery-reared species - Transplant/release molluscs Eight studies examined the effects of transplanting or releasing hatchery-reared mollusc species on their wild populations. One examined abalone in the North Pacific Ocean (Canada), one examined clams off the Strait of Singapore (Singapore), one examined oysters in the North Atlantic Ocean (USA), and four examined scallops in the North Atlantic Ocean and Gulf of Mexico (USA).   COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (8 STUDIES) Mollusc abundance (2 studies): One replicated, before-and-after study in the North Atlantic Ocean found that after transplanting hatchery-reared scallops, abundance of juvenile scallops typically increased, but not that of adult scallops. Two replicated, randomized, controlled studies in the North Atlantic Ocean, found that after releasing hatchery-reared oyster larvae, more spat initially settled using a direct technique compared to a traditional remote technique, and equal number of spat settled on cleaned and natural oyster shells. Mollusc reproductive success (1 study): One replicated, before-and-after study in the North Atlantic Ocean found that after transplanting hatchery-reared scallops, larval recruitment increased across all areas studied. Mollusc survival (5 studies): One replicated study in the Strait of Singapore found that, after transplantation in the field, aquarium-reared clams had a high survival rate. One replicated, controlled study in the North Atlantic Ocean found that after transplanting hatchery-reared scallops, the number of transplanted scallops surviving decreased regardless of the methods used, and maximum mortalities was reported to be 0–1.5%. One replicated, controlled study in the North Pacific Ocean found that transplanting hatchery-reared abalone into the wild reduced survivorship compared to non-transplanted hatchery-reared abalone kept in tanks. Two replicated, randomized, controlled studies in the North Atlantic Ocean found that after releasing hatchery-reared oyster larvae, 61% of the settled spat survived the winter, and settled spat survived equally on cleaned and natural oyster shells. Mollusc condition (3 studies): Two replicated studies in the Strait of Singapore and the North Atlantic Ocean found after transplantation in the wild, aquarium-reared clams and hatchery-reared scallops increased in weight and/or grew. Scallops grew in both free-planted plots and suspended bags but grew more in free-planted plots. One replicated, before-and-after study in the Gulf of Mexico found that after transplanting hatchery-reared scallops, wild populations had not become genetically more similar to hatchery-reared scallops. One replicated, controlled study in the North Atlantic Ocean found that after transplanting hatchery-reared scallops, free-planted scallops developed less shell biofouling than suspended scallops. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2267https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2267Wed, 23 Oct 2019 12:16:17 +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 molluscs Nine studies examined the effects of translocating mollusc species on their wild populations. Two examined scallops in the North Atlantic Ocean (USA) and one examined scallops in the Tasman Sea and South Pacific Ocean (New Zealand). One study examined conch in the Florida Keys (USA). One examined clams in the North Atlantic Ocean (Portugal). One examined abalone in the North Pacific Ocean (USA). One examined mussels in Strangford Lough (UK). Two examined mussels in the Gulf of Corinth (Greece).   COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (8 STUDIES) Mollusc abundance (3 studies): One replicated, controlled, before-and-after study in the North Atlantic Ocean found that translocating bay scallops increased larval recruitment into the adult population compared to before translocation. One before-and-after study in the North Pacific Ocean found that following translocation of adult pink abalone to existing patchy populations, total abalone abundance (translocated and resident) decreased to similar levels as before translocation. One replicated, site comparison study in Strangford Lough found that after translocating horse mussels, the abundance of young mussels was higher in site with translocated mussels compared to both sites without translocated mussels and natural mussel reefs. Mollusc reproductive success (1 study): One replicated, controlled, before-and-after study in the North Atlantic Ocean found that translocating bay scallops did not increase larval production compared to before translocation. Mollusc survival (5 studies): Three replicated studies (one before-and-after and two site comparisons) in the North Atlantic Ocean and in the Tasman Sea and South Pacific Ocean, found that following translocation, scallops and clams survived. Survival of translocated New Zealand scallops was higher in areas closed to commercial fishing compared to fished areas. Two studies in the Gulf of Corinth found that Mediterranean fan mussels survived when translocated to a deep site, and had similar survival compared to naturally-occurring mussels, but did not survive when translocated to a shallow site. Mollusc condition (2 studies): One replicated, site comparison study in the North Atlantic Ocean found that following translocation, clams had similar condition indices to clams in the source site. One study in the Gulf of Corinth found that translocated Mediterranean fan mussels had similar size-specific growth-rates compared to naturally-occurring mussels. BEHAVIOUR (1 STUDY) Mollusc behaviour (1 study): One replicated study in the Florida Keys found that translocating non-reproductive adult queen conch to aggregations of reproductive conch did not have adverse effects on the movement patterns of non-translocated resident conch, and all conch displayed similar total distance travelled, movement rates, migration patterns, home-range sizes, and sociability. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2270https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2270Wed, 23 Oct 2019 12:38:40 +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: Cease or prohibit the harvesting of scallops Three studies examined the effects of ceasing or prohibiting the harvesting of scallops on their populations. One study was in the South Atlantic Ocean (Argentina), one in the English Channel (UK) and one in the Irish Sea (UK).   COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (3 STUDIES) Scallop abundance (3 studies): Two of three site comparison studies (one replicated, one before-and-after) in the South Atlantic Ocean, the English Channel, and the Irish Sea found that in areas where scallop harvesting had stopped scallop abundance was similar, and one found that scallop biomass was higher, compared to harvested areas.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2277https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2277Wed, 23 Oct 2019 12:53:07 +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: Hand-rear orphaned or abandoned young in captivity Six studies evaluated the effects of hand-rearing orphaned mammals. Two were in the USA, one each was in Australia, South Africa and India and one was in six countries across North America, Europe and Asia. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (5 STUDIES) Reproductive success (1 study): One study in India found that three hand-reared orphaned or abandoned greater one-horned rhinoceroses gave birth in the wild. Survival (5 studies): Five studies (including one controlled and one replicated) in Australia, the USA, India and in six countries across North America, Europe and Asia, found that some hand-reared orphaned or abandoned ringtail possums, white-tailed deer, sea otters, bears and greater one-horned rhinoceroses survived for periods of time after release. BEHAVIOUR (1 STUDY) Behaviour change (1 study): A study in South Africa found that a hand-reared, orphaned serval established a home range upon release. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2358https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2358Tue, 26 May 2020 14:14:17 +0100
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What Works in Conservation

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

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