Collected Evidence: Collected Evidence: Use coloured baits to reduce accidental mortality during predator control Two replicated and controlled trials in the USA found that dyed baits were consumed at significantly lower rates than control baits. A replicated, randomised and controlled trial in Australia found no differences in consumption rates of dyed and control baits. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F182https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F182Fri, 01 Jun 2012 16:40:17 +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: Sow crops in spring rather than autumn A replicated, controlled, paired sites study from Sweden found more bird species on areas with spring sown cereals, compared with winter cereals. A before-and-after study from the UK found that several species bred in the study site for the first time after the start of spring sowing. Three studies from Sweden and the UK, two replicated and controlled, found population increases after the start of spring sowing, or higher populations on sites with spring-sown cereals, compared to sites with winter cereals. A before-and-after study from the UK found that ten species did not increase after spring sowing began. No species decreased. A replicated, controlled paired sites study from Sweden found that the benefits of spring-sowing decreased with the proportion of autumn-sown crops in the surrounding area. A replicated, controlled study from Sweden found that hatching success was lower on spring-sown crops than autumn sown.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F207https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F207Sun, 15 Jul 2012 17:16:58 +0100Collected Evidence: Collected Evidence: Plant cereals for whole crop silageA replicated, controlled trial in the UK found that seed-eating birds used CBWCS fields, especially those planted with barley, more than other crops in both summer and winter. Insect-eating species used other crops and grassland more.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F225https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F225Tue, 17 Jul 2012 15:12:29 +0100Collected Evidence: Collected Evidence: Use wildlife refuges to reduce hunting disturbance Three studies from the USA and Europe found that bird densities were higher in refuges where hunting was prohibited, compared to areas with hunting. In addition, two studies found that more birds used hunting-free areas during the open season and on hunting days. No studies investigated the population-level impacts of these refuges.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F278https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F278Tue, 24 Jul 2012 12:34:46 +0100Collected Evidence: Collected Evidence: Use prescribed burning on Australian sclerophyll forest Two of three studies from Australia found no differences in bird species richness in burned sites compared to unburned areas. Three studies found differences in species assemblages in burned and unburned areas, with some species lost and others gained from areas after fire.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F319https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F319Thu, 26 Jul 2012 14:44:29 +0100Collected Evidence: Collected Evidence: Use prescribed burning on coastal habitats Of three studies captured, one replicated, controlled, paired sites study from the USA found that there was a fall in breeding seaside sparrow numbers on a burned site in the year it was burned. The next year, numbers were higher than on an unburned site. A controlled study in Argentina found that tall-grass specialist species were lost from burned areas in the year of burning, but that some habitats recovered by the following year. A replicated controlled study from the USA found no differences in nest predation rates between burned and unburned areas for two years after burning.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F323https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F323Thu, 26 Jul 2012 16:24:19 +0100Collected Evidence: Collected Evidence: Use fire suppression/control Two out of three before-and-after studies, from Australia and the UK, found that five species of bird (including noisy scrub-bird, the target species of one study) increased following fire suppression measures. A before-and-after study in the USA found that open habitat species declined in a pine forest site after fire exclusion, whilst mesic woodland species appeared. A before-and-after study from the UK found that five bird species declined following fire suppression.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F324https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F324Thu, 26 Jul 2012 16:35:35 +0100Collected Evidence: Collected Evidence: Coppice trees Of three studies, one, a before-and-after study in the UK found that a population of European nightjars increased following a series of management interventions, including the coppicing of some birch trees. Two before-and-after studies from the UK and the USA found that the use of coppices by some bird species declined over time. The UK study also found that overall species richness decreased with age, but that some species were more abundant in older stands.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F329https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F329Fri, 27 Jul 2012 14:58:36 +0100Collected Evidence: Collected Evidence: Manage woodland edges for birds We captured three studies of two experiments, of which one, a before-and-after study from the UK, found an increase in the local population of European nightjars following several management interventions, including the management of woodland edges for birds. Two studies of a replicated, controlled paired sites experiment in the USA found that bird abundances were higher in woodland edges with border-edge cuts and that predation on artificial nests was lower than in uncut edges. Scrub- and edge-nesting species were more abundant. Overall species richness and nest success did not differ different between treatments.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F334https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F334Sat, 28 Jul 2012 14:12:39 +0100Collected Evidence: Collected Evidence: Mow or cut reedbeds Of three studies captured, one controlled study from the Netherlands found that warblers nested at lower densities in cut areas of reeds. Productivity and success did not vary between treatments. An unreplicated study from Denmark found that geese grazed at the highest densities on reedbeds cut 5–12 years previously. One replicated study investigated changing water levels in addition to cutting reeds in the UK and found that management did not affect great bittern breeding productivity but did appear to delay territory establishment.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F340https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F340Sat, 28 Jul 2012 20:15:58 +0100Collected Evidence: Collected Evidence: Reduce predation by translocating predatorsTwo studies from France and the USA found local population increases or reduced predationfollowing the translocation of predators away from an area.  A study in Saudi Arabia found that predation was no lower when predators were translocated from the bird release site.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F393https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F393Thu, 09 Aug 2012 13:39:34 +0100Collected Evidence: Collected Evidence: Use supplementary feeding to reduce predation A controlled cross-over experiment from the UK found that there was no difference in grouse adult survival or productivity when supplementary food was provided to hen harrier Circus cyaneus compared to in control areas. This study and another from the USA that used artificial nests found that nest predation rates were reduced in areas when supplementary food was provided to predators. A second study from the USA found no such effect.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F417https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F417Thu, 16 Aug 2012 15:42:26 +0100Collected Evidence: Collected Evidence: Reduce inter-specific competition for nest sites of songbirds by removing competitor species Two studies from Australia found increases in bird populations and species richness after the control of noisy miners Manorina melanocephala – a native but hyper-competitive species. A controlled study from Italy found that blue tits Parus caeruleus nested in more nest boxes when hazel dormice Muscardinus avellanarius were excluded from nest boxes over winter.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F424https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F424Fri, 17 Aug 2012 17:28:29 +0100Collected Evidence: Collected Evidence: Remove eggs from wild nests to increase reproductive output A replicated study from Mauritius found that harvesting entire clutches appeared to increase Mauritius kestrels Falco punctatus productivity more effectively than removing individual eggs as they were laid. A replicated study over 30 years in Canada (Kuyt 1996) found that wild whooping cranes Grus americana reproductive success was higher for nests with one or two eggs removed than for control nests. A single study from the USA found that removing bald eagle Haliaeetus leucocephalus eggs from wild nests for hand-rearing did not appear to greatly affect the wild population.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F477https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F477Thu, 30 Aug 2012 13:27:46 +0100Collected Evidence: Collected Evidence: Provide artificial nesting sites for wildfowl using artificial/floating islands Two studies from North America found that a variety of wildfowl used artificial islands and floating rafts, and had high (70–80%) nesting success. A replicated study from across the UK found that wildfowl preferentially nested on well vegetated islands, compared to bare ones.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F483https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F483Sat, 01 Sep 2012 16:49:16 +0100Collected Evidence: Collected Evidence: Provide nesting habitat for birds that is safe from extreme weather A small from New Zealand found Chatham Island oystercatchers Haematopus chathamensis used raised nest platforms made from car tyres (designed to raise nests above the level of storm surges). The success of these nests is not reported. Two replicated, controlled studies from the USA found that the nesting success of terns and waders was no higher on specially raised areas of nesting substrate, compared to unraised areas, with one study finding that a similar proportion of nests were lost to flooding in raised and unraised areas.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F504https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F504Thu, 06 Sep 2012 13:55:55 +0100Collected Evidence: Collected Evidence: Foster eggs or chicks of waders with wild conspecifics Two small trials in North America found that piping plovers Charadrius melodus accepted chicks introduced into their broods, although in one case the chick died later the same day. A replicated study from New Zealand found that survival of fostered black stilts Himantopus novasezelandiae was higher for birds fostered to conspecifics rather than a closely related species.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F508https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F508Thu, 06 Sep 2012 14:30:39 +0100Collected Evidence: Collected Evidence: Foster eggs or chicks of woodpeckers with wild conspecifics Three studies from the USA found that red-cockaded woodpecker Picoides borealis chicks fostered to conspecifics had high fledging rates. One small study found that fostered chicks survived better than chicks translocated with their parents.    Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F514https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F514Thu, 06 Sep 2012 16:29:20 +0100Collected Evidence: Collected Evidence: Provide supplementary food for auks to increase reproductive success Two replicated and controlled studies from the UK found that Atlantic puffin Fratercula arctica chicks provided with supplementary food were significantly heavier than control chicks. One study found differences between populations, suggesting some are more food-limited than others. The two UK studies found that fed chicks fledged at the same time as controls, whilst a randomised, replicated and controlled study from Canada found that tufted puffin Fratercula cirrhata chicks supplied with supplementary food fledged later than controls. The Canadian study found that fed chicks had faster growth by some, but not all, metrics.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F524https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F524Sat, 08 Sep 2012 13:32:31 +0100Collected Evidence: Collected Evidence: Provide supplementary food for parrots to increase reproductive success Two studies from New Zealand found some evidence that providing supplementary food for kakapos Strigopus habroptilus increased the number of breeding attempts made, whilst a third study found that birds provided with specially-formulated pellets appeared to have larger clutches than those fed on nuts. One study found no evidence that providing food increased the number of nesting attempts.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F536https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F536Sun, 09 Sep 2012 19:43:26 +0100Collected Evidence: Collected Evidence: Provide supplementary food for vultures to increase adult survival A before-and-after study from Spain found a large increase in griffon vulture Gyps fulvus population in the study area following multiple interventions including supplementary feeding. Two studies from the USA and Israel found that Californian condors Gymnogyps californianus and Egyptian vultures Neophron percnopterus fed on many of the carcasses provided for them. The Egyptian vultures were sometimes dominated by larger species at a feeding station supplied twice a month, but not at one supplied every day.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F545https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F545Sun, 16 Sep 2012 09:10:04 +0100Collected Evidence: Collected Evidence: Provide supplementary food for woodpeckers to increase adult survival One replicated, controlled study from the USA found that 12 female downy woodpeckers Picoides pubescens supplied with supplementary food had higher nutritional statuses than unfed birds. However, two analyses of a replicated, controlled study of 378 downy woodpeckers from the USA found that they did not have higher survival rates or nutritional statuses than unfed birds.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F551https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F551Sun, 16 Sep 2012 09:42:41 +0100Collected Evidence: Collected Evidence: Can supplementary feeding increase predation or parasitism? A replicated, controlled study in the USA found that providing seeds in predictable areas did not increase predation on seven species of songbird. A replicated and controlled trial in Spain found higher levels of potentially dangerous gut microflora when fed on livestock carrion, compared to those fed on wild rabbits. A replicated study in Spain found higher levels of predation on artificial nests close to carcasses provided for vultures.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F554https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F554Sat, 22 Sep 2012 20:37:07 +0100Collected Evidence: Collected Evidence: Clip birds’ wings on release Two studies from Saudi Arabia and Hawaii found that bustards and geese had lower survival when released in temporary exclosures with clipped wings, compared to birds released with unclipped wings. A review of cackling goose Branta hutchinsii conservation found that wing-clipped or moulting wild adult geese proved a better strategy than releasing young geese. A review of northern bald ibis (waldrapp) Geronticus eremita conservation found no differences in survival between birds released with clipped and unclipped wings in Israel.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F633https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F633Sun, 14 Oct 2012 23:29:34 +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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