Collected Evidence: Collected Evidence: Plant cereals in wide-spaced rows A replicated and controlled study from the UK found that planting cereals in wide-spaced rows “offered benefits over conventional wheat for Eurasian skylarks, but details were not given. Another replicated and controlled study from the UK found that fields with wide-spaced rows had fewer skylark nests than control or skylark plot fields. A replicated and controlled study from the UK found that the faecal content (and therefore diet) of skylark nestlings was similar between control fields and those with wide-spaced rows.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F216https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F216Tue, 17 Jul 2012 11:58:51 +0100Collected Evidence: Collected Evidence: Create beetle banks A small UK study found that a site with beetle banks had increasing populations of rare or declining species, although several other interventions were used on this site. A literature review from the UK found that grey partridge Perdix perdix populations were far larger on sites with beetle banks and other interventions than on other farms. Two replicated studies from the UK also investigated population-level effects: one found that no bird species were strongly associated with beetle banks; the second found no relationship between beetle banks and grey partridge population density trends. A UK literature review found that two bird species nested in beetle banks and that some species were more likely to forage in them than others. A study in the UK found that one of two species used beetle banks more than expected. The other used them less than other agri-environment options.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F217https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F217Tue, 17 Jul 2012 12:04:26 +0100Collected Evidence: Collected Evidence: Use volunteers to collect downed birds and rehabilitate them We found no evidence that report on the effectiveness of using volunteers to collect and rehabilitate downed birds. '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%2F472https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F472Wed, 29 Aug 2012 16:42:08 +0100Collected Evidence: Collected Evidence: Water nesting mounds to increase incubation success in malleefowlA small controlled in Australia found that two malleefowl Leipoa ocellata nests were abandoned after they dried out, despite being watered, although unwatered nests were abandoned much earlier.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F473https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F473Wed, 29 Aug 2012 16:48:28 +0100Collected Evidence: Collected Evidence: Incorporate plant remains into the soil that produce weed-controlling chemicalsWeeds: Six studies (including six randomised, replicated, controlled tests) from Asia, Europe and North America examined the effect of allelopathic plant remains on weeds by comparing amended soils with weeded controls. Three studies found a reduction in weed growth, and three found effects varied between years, weed groups, or the type of weeding method in controls.Four studies from Asia  and North America examined the effect on weeds by comparing amended soils with unweeded controls. Two studies found a reduction in weed growth, but one found that residues applied too far in advance of crop planting had the reverse effect. Two studies found that effects varied between trials, weed species or the type of residue used.Two studies, including one randomised, replicated, controlled laboratory study, found that the decrease in weeds did not last beyond a few days or weeks after residue incorporation. Pests: One randomised, replicated, controlled study in the Philippines found mixed effects on pests. Crop growth: Two of three studies found crop growth was inhibited by allelopathic plant remains, but this could be minimised by changing the timing of application. One study found effects varied between years. Yield: Three randomised, replicated, controlled studies compared yields in amended plots with weeded controls and found positive, negative and mixed effects. Three studies compared amended plots with unweeded controls, two found positive effects on yield and one found mixed effects (depending on the crop). Profit: One study found that amending soils increased profit compared to unweeded controls, but not compared to weeded controls.   Crops studied were beans, cotton, maize, rice and wheat.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F728https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F728Thu, 30 May 2013 13:50:22 +0100Collected 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: Cover the ground using techniques other than plastic mats after restoration planting One replicated, randomized, controlled study in the USA found that covering the ground with mulch after planting increased total plant cover.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1240https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1240Fri, 03 Jun 2016 09:38:37 +0100Collected Evidence: Collected Evidence: Close non-essential roads as soon as logging operations are complete We found no evidence for the effects of closing non-essential roads as soon as logging operations are complete 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%2F1496https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1496Tue, 17 Oct 2017 19:48:39 +0100Collected Evidence: Collected Evidence: Physically exclude pedestrians from peatlands We found no studies that evaluated the effects on peatland vegetation of physically excluding pedestrians from peatlands. ‘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%2F1752https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1752Mon, 27 Nov 2017 21:32:15 +0000Collected Evidence: Collected Evidence: Treat bat hibernacula environments to reduce the white-nose syndrome pathogen reservoir We found no studies that evaluated the effects of treating hibernacula environments to reduce the white-nose syndrome pathogen reservoir 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%2F2007https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2007Wed, 05 Dec 2018 15:37:15 +0000Collected Evidence: Collected Evidence: Treat bats for infection with white-nose syndrome Two studies evaluated the effects of treating bats with a probiotic bacterium to reduce white-nose syndrome infection. One study was in Canada and one in the USA. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (2 STUDIES) Survival (2 studies): One randomized, controlled study in Canada found that treating little brown bats with a probiotic bacterium at the time of infection with white-nose syndrome (but not 21 days prior) increased survival within cages in a laboratory. One randomized, controlled study in the USA found that treating little brown bats with a probiotic bacterium within a mine increased survival for free-flying bats, but not caged bats. Condition (2 studies): One randomized, controlled study in Canada found that little brown bats caged in a laboratory and treated with a probiotic bacterium at the time of infection with white-nose syndrome had reduced symptoms of the disease, but bats treated 21 days prior to infection had worse symptoms. One randomized, controlled study in the USA found that little brown bats kept within cages in a mine and treated with a probiotic bacterium had a similar severity of white-nose syndrome to untreated bats. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2008https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2008Wed, 05 Dec 2018 15:40:15 +0000Collected Evidence: Collected Evidence: Pay monetary compensation for habitat damage remediation We found no studies that evaluated the effects of paying monetary compensation for habitat damage remediation 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%2F2263https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2263Wed, 23 Oct 2019 10:58:53 +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: Install tunnels/culverts/underpass under railways Six studies evaluated the effects on mammals of installing tunnels, culverts or underpass under railways. Two studies were in Spain, one was in each of Australia, Canada and the Netherlands and one reviewed literature from a range of countries. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Survival (1 study): A review found that most studies recorded no evidence of predation in or around passages under railways or roads of mammals using those passages. BEHAVIOUR (5 STUDIES) Use (5 studies): Five studies, in Spain, Australia, Canada and the Netherlands, found that tunnels, culverts and underpasses beneath railways were used by a range of mammals including rodents, rabbits and hares, carnivores, marsupials, deer and bears. One of these studies found that existing culverts were used more than were specifically designed wildlife tunnels. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2519https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2519Mon, 08 Jun 2020 09:27:22 +0100Collected Evidence: Collected Evidence: Train captive-bred mammals to avoid predators Two studies evaluated the effects of training captive-bred mammals to avoid predators. One study was in Australia and one was in the USA. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Survival (1 study): A randomized, controlled study in the USA found that training captive-born juvenile black-tailed prairie dogs, by exposing them to predators, increased post-release survival. BEHAVIOUR (1 STUDY) Behaviour change (1 study): A before-and-after study in Australia found that rufous hare-wallabies could be conditioned to become wary of potential predators. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2520https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2520Mon, 08 Jun 2020 09:30:41 +0100Collected Evidence: Collected Evidence: Use acoustic devices at aquaculture systems Six studies evaluated the effects on marine and freshwater mammals of using acoustic devices at aquaculture systems. Four studies were in the North Atlantic Ocean (USA, UK), one was in the Reloncaví fjord (Chile) and one in the Mediterranean Sea (Italy). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (0 STUDIES) OTHER (6 STUDIES) Human-wildlife conflict (6 studies): Four of six studies (including five before-and-after and/or site comparison studies and one controlled study) in the North Atlantic Ocean, the Reloncaví fjord and the Mediterranean Sea found that using acoustic devices at salmon farms reduced predation on caged salmon by grey seals, harbour seals and South American sea lions, or reduced the number of harbour seals approaching a fish cage. The two other studies found that using acoustic devices did not reduce harbour seal predation at salmon farms, or reduce the presence, approach distances, groups sizes or time spent around fin-fish farms by common bottlenose dolphins. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2775https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2775Thu, 04 Feb 2021 15:29:04 +0000Collected Evidence: Collected Evidence: Translocate mammals away from aquaculture systems to reduce human-wildlife conflict Two studies evaluated the effects of translocating mammals away from aquaculture systems to reduce human-wildlife conflict. Both studies were in the Tasman Sea and one was also in the Southern Ocean (Tasmania). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (0 STUDIES)       OTHER (2 STUDIES) Human-wildlife conflict (2 studies): Two studies (including one site comparison study) in the Tasman Sea (one also in the Southern Ocean) found that more than half or nearly all of Australian and New Zealand fur seals translocated away from salmon farms returned. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2776https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2776Thu, 04 Feb 2021 15:43:44 +0000Collected Evidence: Collected Evidence: Lower water level to restore degraded brackish/salt marshesWe found no studies that evaluated the effects, on vegetation, of lowering the water level to restore degraded brackish/salt 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%2F3031https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3031Wed, 31 Mar 2021 15:20:22 +0100Collected Evidence: Collected Evidence: Lower water level to restore degraded freshwater swampsWe found no studies that evaluated the effects, on vegetation, of lowering the water level to restore degraded 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%2F3032https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3032Wed, 31 Mar 2021 15:20:38 +0100Collected Evidence: Collected Evidence: Create mounds or hollows before planting non-woody plants: brackish/saline wetlands One study evaluated the effects, on vegetation, of creating mounds or hollows in brackish/saline wetlands before planting emergent, non-woody plants. The study was in the USA. VEGETATION COMMUNITY   VEGETATION ABUNDANCE Individual species abundance (1 study): One replicated, randomized, paired, controlled study in an estuarine salt marsh in the USA found that amongst plots sown/planted with dwarf saltwort Salicornia bigelovii, those that had been excavated into depressions had lower cover of dominant pickleweed Salicornia virginica – over the first growing season – than plots left at ground level. VEGETATION STRUCTURE   OTHER Germination/emergence (1 study): One replicated, randomized, paired, controlled study in an estuarine salt marsh in the USA found that there were no more (sometimes fewer) dwarf saltwort Salicornia bigelovii seedlings in excavated depressions than in level plots, two months after sowing saltwort seeds. Survival (1 study): The same study found that the survival rate of dwarf saltwort Salicornia bigelovii transplants was not greater (sometimes lower) in excavated depressions than in level plots. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3287https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3287Sat, 10 Apr 2021 17:34:58 +0100Collected Evidence: Collected Evidence: Create mounds or hollows before planting trees/shrubs: freshwater wetlands Three studies evaluated the effects, on vegetation, of creating mounds or hollows in freshwater wetlands before planting trees/shrubs. All three studies were in the USA. VEGETATION COMMUNITY Community composition (1 study): One replicated, site comparison study of 10-year-old restored/created freshwater wetlands in the USA reported that adding coarse woody debris to wetlands before planting trees/shrubs affected the composition of the ground vegetation layer, but not the tree layer. Overall richness/diversity (2 studies): Two studies in freshwater wetlands in the USA reported that creating mounds or hollows before planting trees/shrubs had no clear or significant effect on plant species richness and diversity 10–12 years later. In one of the studies, the same was true for bryophyte, herb and woody plants richness separately. VEGETATION ABUNDANCE   VEGETATION STRUCTURE Height (1 study): One replicated, paired, controlled study in created freshwater wetlands in the USA found that the average height of white cedar Thuja occidentalis saplings typically increased more, between two and five years after planting, in created mounds than on lower (occasionally flooded) ground. OTHER                                         Survival (1 study): One replicated, paired, controlled study in created freshwater wetlands in the USA found that white cedar Thuja occidentalis seedlings had higher survival rates when planted into created mounds than on lower (occasionally flooded) ground. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3288https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3288Sat, 10 Apr 2021 17:35:08 +0100Collected Evidence: Collected Evidence: Cease or prohibit all types of fishing We found no studies that evaluated the effects on reptile populations of ceasing or prohibiting all types of fishing. ‘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%2F3543https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3543Tue, 07 Dec 2021 17:21:27 +0000Collected Evidence: Collected Evidence: Cease or prohibit commercial fishing We found no studies that evaluated the effects on reptile populations of ceasing or prohibiting commercial fishing. ‘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%2F3544https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3544Tue, 07 Dec 2021 17:22:46 +0000Collected Evidence: Collected Evidence: Relocate nests/eggs for artificial incubation: Crocodilians Six studies evaluated the effects of relocating nests/eggs for artificial incubation on crocodilian populations. Two studies were in the USA and one study was in each of Zimbabwe, Argentina, Venezuela and Australia. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (6 STUDIES) Reproductive success (5 studies): Two replicated studies in Zimbabwe and the USA reported that hatching success for 20,000 Nile crocodile eggs and >30,000 American alligator eggs that were artificially incubated was 74% and 61%. Two studies (including one replicated study) in Argentina and Venezuela reported that 43–100% of road-snouted caiman eggs, 66% of American crocodile eggs and 54% of Orinoco crocodile eggs hatched successfully following artificial incubation. One replicated, before-and-after study in Australia reported that hatching success of artificially incubated saltwater crocodile eggs differed when the project was under local compared to external management. Condition (1 study): One replicated, controlled, paired study in the USA found that American alligator eggs relocated for artificial incubation produced larger hatchlings than eggs left in situ. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3799https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3799Wed, 15 Dec 2021 19:14:49 +0000Collected Evidence: Collected Evidence: Relocate nests/eggs for artificial incubation: Tuatara Two studies evaluated the effects of relocating nests/eggs for artificial incubation on tuatara populations. Both studies were in New Zealand. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (2 STUDIES) Reproductive success (2 studies): One of two replicated studies (including one controlled study) in New Zealand reported that hatching success of tuatara eggs relocated for artificial incubation was 86–100%. The other study reported hatching success of 44%. Condition (1 study): One replicated, controlled study in New Zealand found that 10 months after hatching, artificially incubated tuatara were larger that those from natural nests. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3800https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3800Wed, 15 Dec 2021 19:27:29 +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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