Collected Evidence: Collected Evidence: Introduce and enforce legislation to control hunting of bats We found no studies that evaluated the effects of introducing and enforcing legislation to control the hunting of bats on bat 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%2Fwww.conservationevidence.com%2Factions%2F984https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F984Fri, 20 Dec 2013 14:29:41 +0000Collected Evidence: Collected Evidence: Introduce and enforce legislation to regulate harvesting of bat guano We found no studies that evaluated the effects of introducing and enforcing legislation to regulate the harvesting of bat guano on bat 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%2Fwww.conservationevidence.com%2Factions%2F987https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F987Fri, 20 Dec 2013 14:32:49 +0000Collected Evidence: Collected Evidence: Introduce beavers to impede water flow in forest watercourses We found no evidence for the effects of introducing beavers to impede water flow in forest watercourses on forests. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested 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%2Fwww.conservationevidence.com%2Factions%2F1187https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1187Thu, 19 May 2016 11:46:07 +0100Collected Evidence: Collected Evidence: Introduce certification for bat-friendly crop harvesting regimes We found no studies that evaluated the effects of introducing certification for bat-friendly crop harvesting regimes on bat 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%2Fwww.conservationevidence.com%2Factions%2F1954https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1954Tue, 04 Dec 2018 12:23:48 +0000Collected Evidence: Collected Evidence: Introduce catch shares We found no studies that evaluated the effects of introducing catch shares on subtidal benthic invertebrate populations.   ‘We found no studies’ means that we have not yet found any studies that have directly evaluated this intervention during our systematic journal and report searches. Therefore, we have no evidence to indicate whether or not the intervention has any desirable or harmful effects.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2113https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2113Tue, 22 Oct 2019 09:43:38 +0100Collected Evidence: Collected Evidence: Introduce and enforce legislation to prevent intentional killing of mammals at aquaculture systems We found no studies that evaluated the effects of introducing and enforcing legislation to prevent intentional killing of mammals at aquaculture systems. ‘We found no studies’ means that we have not yet found any studies that have directly evaluated this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2745https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2745Tue, 02 Feb 2021 16:43:17 +0000Collected Evidence: Collected Evidence: Introduce and enforce regulations to prevent the use of harmful deterrents on mammals at aquaculture systems We found no studies that evaluated the effects of introducing and enforcing regulations to prevent the use of harmful deterrents on mammals at aquaculture systems. ‘We found no studies’ means that we have not yet found any studies that have directly evaluated this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2746https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2746Tue, 02 Feb 2021 16:45:37 +0000Collected Evidence: Collected Evidence: Introduce and enforce legislation to prevent intentional killing of mammals at wild fisheries We found no studies that evaluated the effects of introducing and enforcing legislation to prevent intentional killing of mammals at wild fisheries. ‘We found no studies’ means that we have not yet found any studies that have directly evaluated this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2778https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2778Thu, 04 Feb 2021 15:51:27 +0000Collected Evidence: Collected Evidence: Introduce and enforce regulations to prevent the use of harmful deterrents on mammals at wild fisheries We found no studies that evaluated the effects of introducing and enforcing regulations to prevent the use of harmful deterrents on mammals at wild fisheries. ‘We found no studies’ means that we have not yet found any studies that have directly evaluated this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2779https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2779Thu, 04 Feb 2021 15:59:06 +0000Collected Evidence: Collected Evidence: Introduce and enforce regulations for sustainable hunting of marine and freshwater mammals for traditional subsistence and handicrafts We found no studies that evaluated the effects of introducing regulations for sustainable hunting of marine and freshwater mammals for traditional subsistence and handicrafts. ‘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%2Fwww.conservationevidence.com%2Factions%2F2789https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2789Thu, 04 Feb 2021 16:26:55 +0000Collected Evidence: Collected Evidence: Introduce economic incentives to encourage sustainable fishing We found no studies that evaluated the effects of introducing economic incentives to encourage sustainable fishing on marine fish populations.  ‘We found no studies’ means that we have not yet found any studies that have directly evaluated this intervention during our systematic journal and report searches. Therefore, we have no evidence to indicate whether or not the intervention has any desirable or harmful effects. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2811https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2811Fri, 05 Feb 2021 10:03:40 +0000Collected Evidence: Collected Evidence: Introduce fishing gear exchange programmes to encourage fishers to use gear that reduces unwanted catch of mammals We found no studies that evaluated the effects of introducing fishing gear exchange programmes to encourage fishers to use gear that reduces unwanted catch of mammals on marine and freshwater mammal populations. ‘We found no studies’ means that we have not yet found any studies that have directly evaluated this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2834https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2834Fri, 05 Feb 2021 16:07:26 +0000Collected Evidence: Collected Evidence: Introduce and enforce regulations for marine and freshwater mammal watching tours Four studies evaluated the effects of introducing regulations for marine and freshwater mammal watching tours on marine mammals. One study was in each of the North Atlantic Ocean (the Azores), the Cananéia estuary (Brazil), the South Pacific Ocean (Australia) and the Bass Strait (Australia). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (4 STUDIES) Behaviour change (4 studies): Two controlled studies in the North Atlantic Ocean and South Pacific Ocean found that when whale-watching vessels followed approach regulations, fewer sperm whales and humpback whale pods changed their behaviours (e.g. swimming speed, aerial displays) or avoided the vessels compared to when regulations were not followed, but direction of movement and diving patterns or diving behaviours did not differ. One replicated, controlled study in the Cananéia estuary found that when tour boats followed approach regulations, fewer Guiana dolphins displayed negative behaviours (e.g. moving away, diving, groups separating). One study in the Bass Strait found that when boats approached a seal colony to 75 m, more seals remained on shore than when boats approached to 25 m. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2838https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2838Fri, 05 Feb 2021 16:16:26 +0000Collected Evidence: Collected Evidence: Introduce and enforce water quality regulations for aquaculture systems We found no studies that evaluated the effects of introducing and enforcing water quality regulations for 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%2Fwww.conservationevidence.com%2Factions%2F2876https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2876Mon, 08 Feb 2021 11:41:53 +0000Collected Evidence: Collected Evidence: Introduce fragments of non-woody plants: freshwater wetlands Five studies evaluated the effects, on vegetation, of introducing fragments of emergent, non-woody plants to freshwater wetlands. Three studies were in the USA. Two studies were in one marsh in Australia, but used different experimental set-ups. VEGETATION COMMUNITY   VEGETATION ABUNDANCE Overall abundance (2 studies): Two replicated, randomized, paired, controlled, before-and-after studies in a floodplain marsh in Australia found that plots planted with wick grass Hymenachne acutigluma had similar overall vegetation cover to unplanted plots after one year. One of the studies continued for longer, and found that planted plots had greater overall vegetation cover than unplanted plots after three years. Herb abundance (1 study): One replicated, randomized, paired, controlled, before-and-after study in a floodplain marsh in Australia found that plots planted with wick grass Hymenachne acutigluma had similar overall sedge/grass cover to unplanted plots after one year. Individual species abundance (4 studies): Four studies quantified the effect of this action on the abundance of individual plant species. For example, of two replicated, randomized, paired, controlled, before-and-after studies in a floodplain marsh in Australia, one found that wick grass Hymenachne acutigluma was more frequent and had greater cover, after 1–3 years, in plots where its runners had been planted than where they had not been planted. The other study reported that wick grass cover was present, with approximately 1% cover, in 5 of 10 plots where its runners had been planted. This study monitored vegetation one year after planting. VEGETATION STRUCTURE   OTHER Germination/emergence (1 study): One replicated, randomized, paired, controlled study in a floodplain marsh in Australia found that planting wick grass Hymenachne acutigluma had no significant effect on the germination rate of invasive mimosa Mimosa pigra over three years. Survival (5 studies): Two replicated studies planted sedge Carex fragments into freshwater wetlands in the USA. One study reported 38–79% survival of planted tubers over one growing season, whilst the other study reported 0–73% survival of planted rhizomes after 1–9 months. One replicated study in a tidal freshwater marsh in the USA reported that 6–31% of planted California bulrush Schoenoplectus californicus rhizomes had produced shoots after three months. For two other species, all planted rhizomes died within three months. Two replicated, randomized, paired, controlled, before-and-after studies in a floodplain marsh in Australia reported absence of planted wick grass Hymenachne acutigluma from 17–50% of plots after one year. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3260https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3260Sat, 10 Apr 2021 13:28:02 +0100Collected Evidence: Collected Evidence: Introduce fragments of non-woody plants: brackish/saline wetlands Three studies evaluated the effects, on vegetation, of introducing fragments of emergent, non-woody plants to brackish/saline wetlands. Two studies were in one bog in Canada. One study was in China. VEGETATION COMMUNITY   VEGETATION ABUNDANCE Overall abundance (2 studies): Two replicated, paired, controlled, before-and-after studies in salt-contaminated bogs in Canada found that plots planted with rhizomes or sown with fragments of salt marsh herbs had similar overall vegetation biomass, after one year, to plots that had not been planted or sown. Herb abundance (1 study): One replicated, paired, controlled, before-and-after studies in salt-contaminated bogs in Canada found that plots sown with fragments of salt marsh herbs had greater overall cover of the introduced species, after one year, to unsown plots. However, biomass of the introduced species did not significantly differ between sown and unsown plots. Individual species abundance (2 studies): Two replicated studies (one also before-and-after) in brackish/saline wetlands in Canada and China simply quantified the abundance of herb species, over one year or growing season after planting herb fragments. VEGETATION STRUCTURE   OTHER Germination/emergence (1 study): One replicated study on a tidal flat in China reported that at least 25% of bulrush Scirpus mariqueter corms (bulb-like organs) produced shoots within the first growing season after planting. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3261https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3261Sat, 10 Apr 2021 13:28:14 +0100Collected Evidence: Collected Evidence: Introduce fragments of trees/shrubs: freshwater wetlands One study evaluated the effects, on vegetation, of introducing tree/shrub fragments to freshwater wetlands. The study was in the USA. VEGETATION COMMUNITY   VEGETATION ABUNDANCE   VEGETATION STRUCTURE   OTHER            Survival (1 study): One study in a floodplain swamp clearing in the USA reported 12% overall survival of planted unrooted tree cuttings over two years. For two of four species, no monitored seedlings survived. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3262https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3262Sat, 10 Apr 2021 13:28:25 +0100Collected Evidence: Collected Evidence: Introduce fragments of trees/shrubs: brackish/saline wetlandsWe found no studies that evaluated the effects, on vegetation, of introducing tree/shrub fragments to brackish/saline wetlands.   ‘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%2Fwww.conservationevidence.com%2Factions%2F3263https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3263Sat, 10 Apr 2021 13:28:45 +0100Collected Evidence: Collected Evidence: Introduce and enforce water quality regulations for aquaculture systems We found no studies that evaluated the effects on reptile populations of introducing and enforcing water quality regulations for aquaculture systems. ‘We found no studies’ means that we have not yet found any studies that have directly evaluated this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3581https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3581Wed, 08 Dec 2021 15:26:09 +0000Collected Evidence: Collected Evidence: Introduce fishing gear exchange programs to encourage fishers to use gear that reduces unwanted catch of reptiles We found no studies that evaluated the effects on reptile populations of introducing fishing gear exchange programs to encourage fishers to use gear that reduces unwanted catch of reptiles. ‘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%2Fwww.conservationevidence.com%2Factions%2F3620https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3620Thu, 09 Dec 2021 13:30:36 +0000Collected Evidence: Collected Evidence: Introduce and enforce regulations for reptile watching tours We found no studies that evaluated the effects on reptile populations of introducing and enforcing regulations for reptile watching tours. ‘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%2Fwww.conservationevidence.com%2Factions%2F3644https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3644Thu, 09 Dec 2021 15:30:41 +0000Collected Evidence: Collected Evidence: Introduce an overall catch limit (quota cap or total allowable catch) by fishery or fleet Nine studies examined the effects of introducing overall catch limits by fishery or fleet on marine fish populations. Three studies were worldwide, two studies were in the South Atlantic Ocean (Namibia/South Africa), two studies were in the North Sea (Northern Europe), and one study was in each of the North Sea and Atlantic Ocean (Scotland) and the North Atlantic Ocean (Canada).   COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (6 STUDIES) Abundance (5 studies): Four before-and-after studies (two replicated) in the South Atlantic Ocean, the North Atlantic Ocean and the North Sea reported that following the introduction of overall catch limits for fish there was a higher abundance or biomass of hakes, Atlantic herring and Atlantic halibut, compared to before. One replicated, controlled study of fish stocks worldwide found that overfished stocks of tunas and billfishes had faster increases of biomass when managed using overall catch limits, compared to stocks with other types of control or no management. Reproductive success (1 study): A global review reported that after overall catch limits and minimum landing size were introduced there was strong recruitment of broadbill swordfish for one key stock, while recruitment for four other stocks could not be assessed due to limited data. Survival (2 studies): One before-and-after study and one replicated, controlled study in the North Atlantic Ocean and worldwide found that for fish species with overall catch limits there was a decrease or lower fishing mortality, compared either to before implementation or to stocks without catch limits and those with other controls. BEHAVIOUR (0 STUDIES) OTHER (3 STUDIES) Reduction of unwanted catch (1 study): One replicated, before-and-after study in the North Sea and North Atlantic Ocean found that overall catch limits did not reduce unwanted megrim catch despite a reduction in discards, however this was due to retention of more small but legal-sized megrim, previously discarded. Reduction of fishing effort (1 study): One replicated, before-and-after study in the North Sea found that when annual total allowable catch limits were changed (increased or decreased), half of the otter trawl fleet had corresponding changes in fishing effort (increased or decreased), but there were no changes for the beam trawl fleet. Stock status (1 study): One global systematic review found that in terms of reaching biomass-based management targets fisheries with fleet-wide catch quotas were no different to fisheries managed either by catch shares or effort controls. However, along with catch share fisheries, fewer catch quota stocks were over-exploited than those with effort controls. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3811https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3811Thu, 26 May 2022 15:07:14 +0100Collected Evidence: Collected Evidence: Introduce catch shares Two studies examined the effects of introducing catch shares on marine fish populations. Both were reviews of fisheries worldwide.   COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (2 STUDIES) Abundance (2 studies): One of two worldwide systematic reviews found that fisheries or stocks managed under catch shares were more likely to meet management target levels for biomass sustainability than those that did not meet targets. The other study found there was no difference in performance of biomass-based management targets between fisheries under catch shares, fleet-wide catch caps or fishing effort controls. BEHAVIOUR (0 STUDIES) OTHER (2 studies) Stock status (2 studies): Two worldwide systematic reviews found that catch share fisheries had lower rates of over-exploitation compared to non-catch share fisheries, and a higher proportion of fisheries managed under catch shares either met or exceeded management target levels for rates of exploitation than those that did not meet targets. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3812https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3812Fri, 27 May 2022 08:20:03 +0100Collected Evidence: Collected Evidence: Introduce fishing permit/licence or charter schemes We found no studies that evaluated the effects of introducing fishing permit/licence or charter schemes on marine fish populations.   ‘We found no studies’ means that we have not yet found any studies that have directly evaluated this intervention during our systematic journal and report searches. Therefore, we have no evidence to indicate whether or not the intervention has any desirable or harmful effects. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3816https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3816Fri, 27 May 2022 08:40:24 +0100Collected Evidence: Collected Evidence: Introduce gear exchange programs We found no studies that evaluated the effects of introducing gear exchange programmes on marine fish populations.   ‘We found no studies’ means that we have not yet found any studies that have directly evaluated this intervention during our systematic journal and report searches. Therefore, we have no evidence to indicate whether or not the intervention has any desirable or harmful effects.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3828https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3828Fri, 27 May 2022 09:42:22 +0100
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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