Collected Evidence: Collected Evidence: Use new crop types to benefit wildlife (such as perennial cereal crops) We have captured no evidence for the effects of using new crop types to benefit wildlife (such as perennial cereal crops) 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%2F89https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F89Mon, 24 Oct 2011 21:31:28 +0100Collected Evidence: Collected Evidence: Use mixed stocking A replicated, controlled study in the UK found more spiders, harvestmen and pseudoscorpions on sheep-grazed grassland than on mixed livestock-grazed grassland when suction sampling, but not when pitfall-trapping.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F93https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F93Mon, 24 Oct 2011 21:35:59 +0100Collected Evidence: Collected Evidence: Use mowing techniques to reduce chick mortality A review from the UK found a large increase in corncrake Crex crex populations in the UK following a scheme to delay mowing and promote corncrake-friendly mowing techniques. One replicated controlled study from the UK and a review from the UK found lower levels of mortality of corncrakes and Eurasian skylark Alauda arvensis when wildlife-friendly mowing techniques were used, compared to other techniques.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F192https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F192Wed, 27 Jun 2012 17:30:44 +0100Collected Evidence: Collected Evidence: Use mixed stocking We found no evidence on the effects of mixed stocking on bird 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%2F232https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F232Tue, 17 Jul 2012 15:51:52 +0100Collected Evidence: Collected Evidence: Use netting to exclude fish-eating birds Two replicated studies from Germany and the USA found that netting or closely-spaced string barriers reduced losses of fish or deterred fish-eating birds from fish ponds. A review concluded that excluding birds was an effective way to reduce damage. A series of tests in the Netherlands found that netting or nylon lines over ponds did not prevent birds from landing, but did alter behaviour, whilst a before-and-after study from the USA found that fewer great blue herons Ardea Herodias landed at fish ponds with netting, but that they stayed longer. Two replicated studies from Germany and Israel found that some birds became entangled in netting or closely-spaced string barriers over fish ponds. The Israeli study found that dark, small meshed netting entangled fewer birds than other netting types.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F248https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F248Wed, 18 Jul 2012 12:00:45 +0100Collected Evidence: Collected Evidence: Use nest covers to reduce the impact of research on predation of ground-nesting seabirdsA before-and-after study in Canada found that protecting Caspian tern Sterna caspia nests after researchers disturbed parents from them significantly increased hatching success. This was due to a reduction in predation by ring-billed gulls Larus delawarensis.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F316https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F316Wed, 25 Jul 2012 18:26:31 +0100Collected Evidence: Collected Evidence: Use multiple barriers to protect nests A replicated, controlled study from the USA found no evidence that erecting an electric fence around nests protected by individual barriers increased fledging success in piping plovers Charadrius melodus. A replicated study from the USA found that removing the outer of two nest protection fences after 15 days appeared to reduce predation compared to when both fences were left for 18 days.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F404https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F404Thu, 16 Aug 2012 15:00:00 +0100Collected Evidence: Collected Evidence: Use mirrors to deter nest predators We found no evidence for the effects of mirrors on nest predation rates. '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%2F407https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F407Thu, 16 Aug 2012 15:09:28 +0100Collected Evidence: Collected Evidence: Use naphthalene to deter mammalian predatorsA replicated, controlled study from the USA found that scattering naphthalene moth balls near artificial nests did not affect predation rates.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F408https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F408Thu, 16 Aug 2012 15:11:27 +0100Collected Evidence: Collected Evidence: Use microlites to help birds migrateA review of northern bald ibis Geronticus eremita conservation found that a group of birds followed a microlite from Austria to Italy but none made the return journey.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F640https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F640Sun, 14 Oct 2012 23:58:53 +0100Collected Evidence: Collected Evidence: Use mowing techniques to reduce mortality Eight studies investigated the effects of different mowing techniques on wildlife. Seven studies (including four replicated trials of which one randomized, and one controlled and three reviews) from Germany, Ireland, Switzerland and the UK found that using specific mowing techniques can reduce mortality or injury in birds, mammals, amphibians or invertebrates. A review found the UK corncrake population increased around the same period that Corncrake Friendly Mowing schemes were introduced. One replicated trial found that changing the mowing pattern reduced the number of corncrake chicks killed. Sixty-eight percent of chicks escaped mowing when fields were mown from the centre outwards, compared to 45% during conventional mowing from the field edge inwards. Six studies looked at the effects of using different mowing machinery. Two studies (one review, one randomized, replicated trial) found bar mowers and one report found double chop mowers caused less damage or lower mortality among amphibians and/or invertebrates than other types of mowing machinery. A review found evidence that twice as many small mammals were killed by rotary disc mowers with conditioners compared to double blade mowers. Two studies found that using a mechanical processor or conditioner killed or injured more invertebrates than without a conditioner, however one replicated controlled study found mower-conditioners resulted in higher Eurasian skylark nest survival than using a tedder. A review of studies found that skylark chick survival was four times higher when wider mowing machinery was used, whilst a replicated controlled trial found skylark nest survival was highest when swather mowers and forage harvesters were used.    Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F698https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F698Sun, 09 Dec 2012 10:30:37 +0000Collected Evidence: Collected Evidence: Use mixed pastureWeeds: Two of two studies (both randomised, replicated trials, one also controlled) from the USA found reduced weeds in mixed compared to monoculture pasture. Pests: Five studies from North America measured pests including four randomised, replicated, controlled tests. One study found fewer pests and two studies found reductions in some pest groups or in some pasture mixes. One study found no effect and another found more pests, although the effect was potentially inseparable from grazing treatments. Crop mortality: One randomised, replicated study from the USA found no effect on forage crop mortality caused by nematodes.Yield: Two of five studies (including two randomised, replicated, controlled tests) from North America found increased forage crop yields and two studies found mixed effects depending on the crop type and year. One study found no effect. Crops studied were alfalfa, bird’s-foot trefoil, chicory, cicer milkvetch, clovers, fescues, oats, ryegrass, other grasses, other legumes, rapeseed and turnip.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F721https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F721Thu, 30 May 2013 11:59:00 +0100Collected Evidence: Collected Evidence: Use natural control agents: cleaner wrasse Two studies in Ireland found mixed effects of cleaner wrasse on sea lice numbers infesting salmon. One controlled study found corkwing and goldskinny cleaner wrasse were as effective at controlling lice infestation as chemical treatments. One replicated, controlled study found rockcook cleaner wrasse were ineffective at preventing lice outbreaks. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F738https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F738Mon, 03 Jun 2013 15:28:00 +0100Collected Evidence: Collected Evidence: Use nets to keep primates out of fruit trees One controlled, replicated, before-and-after study in Indonesia found that areas where nets were used to protect crop trees, crop-raiding by orangutans was reduced. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1442https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1442Tue, 17 Oct 2017 11:16:03 +0100Collected Evidence: Collected Evidence: Use moorings which reduce or avoid contact with the seabed (eco- moorings) We found no studies that evaluated the effects of using moorings which reduce or avoid contact with the seabed (eco-moorings) 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%2F2092https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2092Mon, 21 Oct 2019 15:21:52 +0100Collected Evidence: Collected Evidence: Use more than one net on otter trawls We found no studies that evaluated the effects of using more than one net on otter trawls 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%2F2124https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2124Tue, 22 Oct 2019 10:17:39 +0100Collected Evidence: Collected Evidence: Use native species instead of non-native species in aquaculture systems We found no studies that evaluated the effects of using native species instead of non-native species in aquaculture systems 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%2F2155https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2155Tue, 22 Oct 2019 12:05:48 +0100Collected Evidence: Collected Evidence: Use mobile phone communications to warn farmers of problematic mammals (e.g. elephants) We found no studies that evaluated the effects of using mobile phone communications to warn farmers of problematic mammals (e.g. elephants). ‘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%2F2452https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2452Tue, 02 Jun 2020 10:59:20 +0100Collected Evidence: Collected Evidence: Use noise aversive conditioning to deter crop damage by mammals to reduce human-wildlife conflict One study evaluated the effects of using noise aversive conditioning to deter crop damage by mammals to reduce human-wildlife conflict. This study was in the USA. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (0 STUDIES) OTHER (1 STUDY) Human-wildlife conflict (1 study): A replicated, controlled study in USA found that noise aversive conditioning reduced bait consumption by white-tailed deer. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2461https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2461Tue, 02 Jun 2020 11:44:11 +0100Collected Evidence: Collected Evidence: Use negative stimuli to deter consumption of livestock feed by mammals to reduce human-wildlife conflict One study evaluated the effects of using negative stimuli to deter consumption of livestock feed by mammals to reduce human-wildlife conflict. This study was in the USA. KEY COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (0 STUDIES) OTHER (1 STUDY) Human-wildlife conflict (1 study): A replicated, controlled study in the USA found that white-tailed deer presence at cattle feeders was usually reduced by a device that produced a negative stimulus. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2486https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2486Thu, 04 Jun 2020 13:03:54 +0100Collected Evidence: Collected Evidence: Use netting of contrasting colour in a trawl net One study examined the effect of using netting of contrasting colour in a trawl net on marine fish populations. The study was in the Baltic Sea (Denmark).  COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (0 STUDIES) OTHER (1 STUDY) Reduction of unwanted catch (1 study): One replicated, paired, controlled study in the Baltic Sea found that a trawl codend with contrasting black netting used in conjunction with a square mesh escape panel caught a similar amount of undersized cod as a conventional codend. Improved size-selectivity of fishing gear (1 study): One replicated, paired, controlled study in the Baltic Sea found that two designs of contrasting netting colour in trawl codends with square mesh escape windows did not improve the size-selectivity of cod compared to conventional codend netting colour. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2718https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2718Tue, 05 Jan 2021 15:46:48 +0000Collected Evidence: Collected Evidence: Use noise aversive conditioning to deter mammals from fishing gear One study evaluated the effects on marine mammals of using noise aversive conditioning to deter mammals from fishing gear. The study was in the North Pacific Ocean (USA). COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (0 STUDIES) OTHER (1 STUDY) Human-wildlife conflict (1 study): One study in the North Pacific Ocean found that noise aversive conditioning did not reduce bait foraging behaviour by California sea lions. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2819https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2819Fri, 05 Feb 2021 15:12:55 +0000Collected Evidence: Collected Evidence: Use nest covers to protect against human disturbance Two studies evaluated the effects of using nest covers to protect against human disturbance on reptiles. One study was in the USA and one was in Greece. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (2 STUDIES) Reproductive success (2 studies): One of two replicated, controlled studies (including one paired study) in the USA and Greece found that loggerhead turtle nests that were covered with cages had similar hatching success compared to nests that were not covered. The other study found mixed effects of cages on hatching success of loggerhead turtle nests. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3645https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3645Thu, 09 Dec 2021 15:32:25 +0000Collected Evidence: Collected Evidence: Use mixed stocking Three studies evaluated the effects on butterflies and moths of grazing with mixed livestock. All three studies were in the UK and compared grazing with sheep and cattle to sheep only. COMMUNITY RESPONSE (1 STUDY) Richness/diversity (1 study): One replicated, randomized, controlled study in the UK found that grassland plots grazed at low intensity with sheep and cattle had fewer moth species than plots grazed at low intensity with sheep only. POPULATION RESPONSE (3 STUDIES) Abundance (3 studies): Two of three replicated studies (including two randomized, controlled studies and one paired, site comparison study) in the UK found that grassland plots grazed at low intensity with sheep and cattle had a similar abundance of moth caterpillars and small invertebrates including caterpillars to plots grazed at low intensity with sheep only. One of these studies found that in plots grazed at high intensity, the abundance of small invertebrates including caterpillars was lower in plots with sheep and cattle than in sheep only plots. The other study found that grassland plots grazed at low intensity with sheep and cattle had a lower abundance of adult moths than plots grazed at low intensity with sheep only. BEHAVIOUR (0 STUDIES)  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3964https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3964Sun, 14 Aug 2022 10:38:09 +0100Collected Evidence: Collected Evidence: Use motor bar mowers rather than rotary mowers Two studies evaluated the effects on butterflies and moths of using motor bar mowers rather than rotary mowers. Both studies were in Switzerland. COMMUNITY RESPONSE (1 STUDY) Richness/diversity (1 study): One replicated, site comparison study in Switzerland found that farms managed with more in-field agri-environment scheme options, including using bar mowers instead of rotary mowers, had a similar species richness of butterflies to farms with fewer agri-environment scheme options. POPULATION RESPONSE (2 STUDIES) Abundance (1 study): One replicated, site comparison study in Switzerland found that farms managed with more in-field agri-environment scheme options, including using bar mowers instead of rotary mowers, had a similar abundance of butterflies to farms with fewer agri-environment scheme options. Survival (1 study): One replicated, randomized, paired, controlled study in Switzerland1 found that fewer large white caterpillars were killed when meadows were harvested using a hand-pushed bar mower than with a tractor-pulled rotary mower. Condition (1 study): One replicated, randomized, paired, controlled study in Switzerland found that fewer wax model caterpillars were damaged when meadows were harvested using a hand-pushed bar mower than with a tractor-pulled rotary mower. BEHAVIOUR (0 STUDIES)  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3969https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3969Sun, 14 Aug 2022 10:39:04 +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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