Collected Evidence: Collected Evidence: Remove coarse fish We have captured no evidence for the effects of removing coarse fish on farmland wildlife. '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%2F110https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F110Mon, 24 Oct 2011 22:08:13 +0100Collected Evidence: Collected Evidence: Remove earth wires to reduce incidental bird mortalityA before-and-after study and a literature review describe significant reductions in collision mortalities of cranes Grus spp. and grouse Lagopus spp. following the removal of earth wires.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F263https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F263Thu, 19 Jul 2012 13:41:42 +0100Collected Evidence: Collected Evidence: Remove coarse woody debris from forests One of two replicated and controlled studies from the USA found that overall breeding bird abundance and diversity were lower in plots where woody debris was removed, compared to control plots. Several individually-analysed species showed lower abundances. A replicated, controlled before-and-after study from the USA found lower nest survival for black-chinned hummingbirds following debris removal. Some species in both studies increased after debris removal.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F345https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F345Sat, 28 Jul 2012 20:43:34 +0100Collected Evidence: Collected Evidence: Remove brood parasite eggs from target species’ nests A controlled before-and-after study on Puerto Rico found lower rates of parasitism of yellow-shouldered blackbird Agelaius xanthomus nests when shiny cowbird Molothrus bonariensis eggs were removed from nests. A replicated, controlled study from 1997-1999 in grassy fields in New York State, USA found that song sparrow Melospiza melodia nests that had cowbird eggs removed from them had lower success than nests which were parasitised and that did not have eggs removed.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F443https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F443Thu, 23 Aug 2012 15:56:54 +0100Collected Evidence: Collected Evidence: Remove burned trees One replicated, controlled study in Israel1 found that removing burned trees increased total plant species richness. One replicated, controlled study in Spain2 found that removal increased the cover and species richness of some plant species.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1237https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1237Fri, 03 Jun 2016 08:52:10 +0100Collected Evidence: Collected Evidence: Remove and relocate ‘problem’ animals One replicated, before-and-after study in India found that ‘problem’ rhesus monkeys that were translocated, alongside other interventions, survived and remained at the release sites for at least four years. One controlled, before-and-after study in Kenya found that after 16 years, most crop-raiding olive baboons that were translocated from farmland, alongside other interventions, had survived and had similar survival rates compared to non-translocated populations. One before-and-after, site comparison study in the Republic of Congo and Gaboon found that 84% of the ‘problem’ western lowland gorillas that were relocated, alongside other interventions, survived for at least four years. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1422https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1422Tue, 17 Oct 2017 09:04:32 +0100Collected Evidence: Collected Evidence: Relocate primates to non-residential areas We found no evidence for the effects of relocating primates to non-residential areas on primate populations. '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%2F1423https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1423Tue, 17 Oct 2017 09:26:18 +0100Collected Evidence: Collected Evidence: Remove alien invasive vegetation where the latter has a clear negative effect on the primate species in question We found no evidence for the effects of removing alien invasive vegetation on primate populations. '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%2F1533https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1533Thu, 19 Oct 2017 13:35:57 +0100Collected Evidence: Collected Evidence: Remove drill cuttings after decommissioning We found no studies that evaluated the effects of removing drill cuttings after decommissioning 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%2F2064https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2064Mon, 21 Oct 2019 13:47:04 +0100Collected Evidence: Collected Evidence: Remove discarded sediment material from the seabed following cessation of aggregate extraction We found no studies that evaluated the effects of removing discarded sediment material from the seabed following cessation of aggregate extraction 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%2F2074https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2074Mon, 21 Oct 2019 14:36:08 +0100Collected Evidence: Collected Evidence: Remove biofouling organisms/species in aquaculture We found no studies that evaluated the effects of removing biofouling organisms/species in aquaculture 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%2F2163https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2163Tue, 22 Oct 2019 12:13:36 +0100Collected Evidence: Collected Evidence: Remove and clean-up shoreline waste disposal sites One study examined the effects of removing and cleaning-up shoreline waste disposal sites on subtidal benthic invertebrates. The study was in the Southern Ocean (Antarctica).   COMMUNITY RESPONSE (1 STUDY) Overall community composition (1 study): One replicated, controlled, before-and-after study in the Southern Ocean found that after removing and cleaning-up a disused waste disposal site, invertebrate community composition changed, and no further negative impacts were detected, but communities remained different to natural sites. Overall richness/diversity (1 study): One replicated, controlled, before-and-after study in the Southern Ocean found that after removing and cleaning-up a disused waste disposal site, invertebrate species richness did not change over time and remained different to that of natural sites, but no further negative impacts were detected. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2215https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2215Tue, 22 Oct 2019 13:32:05 +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: Remove and relocate invertebrate species before onset of impactful activities We found no studies that evaluated the effects of removing and relocating invertebrate species before onset of impactful activities on their 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%2F2280https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2280Wed, 23 Oct 2019 13:36:46 +0100Collected Evidence: Collected Evidence: Remove burnt trees and branches after wildfire One study evaluated the effects on mammals of removing burnt trees and branches after wildfire. This study was in Spain. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Abundance (1 study): A replicated, randomized, controlled study in Spain found that removing burned trees and branches after wildfire did not increase European wild rabbit numbers compared to removing burned trees but leaving branches in place. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2478https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2478Thu, 04 Jun 2020 11:07:35 +0100Collected Evidence: Collected Evidence: Remove competing vegetation to allow tree establishment in clearcut areas Three studies evaluated the effects on mammals of removing competing vegetation to allow tree establishment in clearcut areas. Two studies were in Canada and one was in the USA. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (3 STUDIES) Use (3 studies): One of three studies (including two controlled studies and one site comparison study), in the USA and Canada, found that where competing vegetation was removed to allow tree establishment in clearcut areas, American martens used the areas more. One study found mixed results for moose and one found no increase in site use by snowshoe hares. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2644https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2644Fri, 12 Jun 2020 16:14:25 +0100Collected Evidence: Collected Evidence: Remove derelict fishing gear from mammals found entangled Two studies evaluated the effects of removing derelict fishing gear from mammals found entangled. One study was in the North Pacific Ocean (USA) and one in the North Atlantic Ocean (USA). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (2 STUDIES) Reproductive success (1 study): One review in the North Pacific Ocean found that after removing derelict fishing gear from Hawaiian monk seals, along with at least seven other interventions to enhance survival, more than a quarter of the seals reproduced. Survival (2 studies): One review in the North Pacific Ocean found that removing derelict fishing gear from Hawaiian monk seals, along with at least seven other interventions to enhance survival, resulted in more than a quarter of the seals surviving. One review in the North Atlantic Ocean found that three common bottlenose dolphins survived for at least 1–4 years after they were disentangled from derelict fishing gear and released. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2892https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2892Mon, 08 Feb 2021 11:56:01 +0000Collected Evidence: Collected Evidence: Remove and clean-up shoreline waste disposal sites We found no studies that evaluated the effects of removing and cleaning up shoreline waste disposal sites on marine and freshwater mammal populations. ‘We found no studies’ means that we have not yet found any studies that have directly evaluated this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2909https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2909Mon, 08 Feb 2021 16:19:56 +0000Collected Evidence: Collected Evidence: Remove debris from freshwater marshesWe found no studies that evaluated the effects, on vegetation, of removing debris from freshwater marshes.   ‘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%2F3161https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3161Tue, 06 Apr 2021 12:48:54 +0100Collected Evidence: Collected Evidence: Remove debris from brackish/salt marshes Two studies evaluated the effects, on vegetation, of removing debris from brackish/salt marshes. Both studies were in the USA. VEGETATION COMMUNITY   VEGETATION ABUNDANCE Overall abundance (1 study): One replicated, paired, site comparison study in a salt marsh in the USA found that overall vegetation cover in patches where debris had been removed remained lower than in undisturbed marsh for one growing season, but had recovered to match undisturbed marsh after two growing seasons. Individual species abundance (2 studies): Two studies quantified the effect of this action on the abundance of individual plant species. For example, the two replicated, site comparison studies in salt marshes in the USA found that the abundance of dominant herb species in impacted vegetation patches was typically lower than in undisturbed marsh one growing season after removing debris, but was sometimes similar to undisturbed marsh. The results depended on the species, metric and type of debris removed. One of the studies also monitored until the second growing season after removing debris; at this point, the cover of both dominant herb species had recovered to match undisturbed marsh. VEGETATION STRUCTURE Height (1 study): One replicated, before-and-after, site comparison study in a salt marsh in the USA found that the maximum height of smooth cordgrass recovered, to match undisturbed marsh, within 45 weeks of removing debris. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3162https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3162Tue, 06 Apr 2021 12:49:05 +0100Collected Evidence: Collected Evidence: Remove debris from freshwater swampsWe found no studies that evaluated the effects, on vegetation, of removing debris from freshwater swamps.   ‘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%2F3163https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3163Tue, 06 Apr 2021 12:49:15 +0100Collected Evidence: Collected Evidence: Remove debris from brackish/saline swampsWe found no studies that evaluated the effects, on vegetation, of removing debris from brackish/saline swamps.   ‘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%2F3164https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3164Tue, 06 Apr 2021 12:49:30 +0100Collected Evidence: Collected Evidence: Remove derelict fishing gear from reptiles found entangled We found no studies that evaluated the effects on reptile populations of removing derelict fishing gear from reptiles found entangled. ‘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%2F3568https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3568Wed, 08 Dec 2021 15:07:01 +0000Collected Evidence: Collected Evidence: Relocate reptiles (including eggs and hatchlings) following oil spills Studies investigating the effect of relocating reptiles are discussed in Species management. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3577https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3577Wed, 08 Dec 2021 15:20:01 +0000Collected Evidence: Collected Evidence: Remove coal combustion waste to reduce contamination of terrestrial and aquatic habitats We found no studies that evaluated the effects on reptile populations of removing coal combustion waste to reduce contamination of terrestrial and aquatic habitats. ‘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%2F3594https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3594Wed, 08 Dec 2021 16:23:34 +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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