Collected Evidence: Collected Evidence: Enforce legislation to protect birds against persecution Two before-and-after studies have evaluated effects of legislative protection on bird species in Europe. Both found that legislation protects bird populations. One found increased population levels of raptors in Scotland, following protective legislation. One found increased survival of kestrels in Denmark stricter protection, but not necessarily population-level responses. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F101https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F101Mon, 24 Oct 2011 21:55:47 +0100Collected Evidence: Collected Evidence: Control invasive non-native plants on farmland (such as Himalayan Balsam, Japanese knotweed) Two randomized, replicated, controlled trials in the Czech Republic found that removing all flower heads of giant hogweed plants at peak flowering time dramatically reduced seed production in giant hogweed.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F104https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F104Mon, 24 Oct 2011 21:59:27 +0100Collected Evidence: Collected Evidence: Control bracken One systematic review found that the herbicide asulam reduced bracken abundance if applied repeatedly, but cutting may be equally effective. A replicated laboratory trial in the UK found that the herbicide asulam inhibited the growth of three common moss species that commonly grow in association with bracken, when exposed over three weeks, but not if only exposed for 24 hours.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F105https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F105Mon, 24 Oct 2011 22:00:36 +0100Collected Evidence: Collected Evidence: Control mink A systematic review found seven studies demonstrating that trapping appears to be an effective method of reducing American mink populations, but firm conclusions could not be made due to limitations in experimental design. A large-scale trapping programme in the UK demonstrated that American mink have been successfully eradicated over a large area and this may have been associated with some localized water vole expansions. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F107https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F107Mon, 24 Oct 2011 22:02:53 +0100Collected Evidence: Collected Evidence: Protect individual nests of ground-nesting birds Two replicated, randomized, controlled studies from Sweden found providing nest exclosures offered some benefits to ground-nesting birds. One study found that protected nests had higher average daily survival rates than unprotected nests for both common redshank and northern lapwing, however, this study also reported higher predation of adult redshank on protected nests. One study found that the average hatching rate for southern dunlin was higher for protected rather than unprotected nests. This study also found no difference in the number of fledglings, breeding adults or new recruits during two periods with and without nest protection.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F108https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F108Mon, 24 Oct 2011 22:04:47 +0100Collected Evidence: Collected Evidence: Remove flood defence banks to allow inundation One controlled before-and-after study from the UK found more bird territories and species on a stretch of river modified to allow inundation of river edges compared to a channelized section of river. One study from Belgium found that a combination of mowing and flooding resulted in increased plant species richness in meadow plots, but infrequently flooded, mown plots had more plant species than frequently flooded, non-mown plots.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F122https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F122Tue, 01 Nov 2011 21:17:40 +0000Collected Evidence: Collected Evidence: Add yellow rattle seed Rhinanthus minor to hay meadows A review of studies from the UK found that adding hay rattle seed helped other sown target meadow species to colonize and that more plant species were found when yellow rattle was present. A randomized, replicated controlled trial in the UK found that yellow rattle could be established on a pasture field by ‘slot seeding’.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F129https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F129Mon, 14 Nov 2011 21:56:48 +0000Collected Evidence: Collected Evidence: Implement 'mosaic management', a Dutch agri-environment option A replicated, controlled, before-and-after study from the Netherlands found that northern lapwing population trends changed from decreases to increases following the introduction of mosaic management. Three other species of wading bird did not show such a response and Eurasian oystercatcher populations did less well under mosaic management than other management types. A replicated, paired sites study in the Netherlands that black-tailed godwit had higher productivity under mosaic management than other management types due to higher nest survival, and nests were less likely to be trampled by livestock or destroyed by mowing under mosaic management.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F130https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F130Mon, 14 Nov 2011 22:01:50 +0000Collected Evidence: Collected Evidence: Manage heather, gorse or grass by burning A long-term replicated controlled trial in Switzerland found that annual spring burning of calcareous grassland did not increase plant species richness relative to abandoned plots, after 15 years. A replicated controlled trial in Northern Ireland found that heather moorland subject to a single burn had more plant species eight years after the management, than control unburned plots.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F152https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F152Sat, 14 Jan 2012 15:22:28 +0000Collected Evidence: Collected Evidence: Create open patches or strips in permanent grassland Two studies (both randomized, replicated and controlled) investigated the effects of creating open strips in permanent grassland. One trial from the UK found that more Eurasian skylarks used fields containing open strips, but variations in skylark numbers were too great to draw conclusions from this finding. One trial from Scotland found insect numbers in grassy headlands initially dropped when strips were cleared.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F563https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F563Tue, 25 Sep 2012 17:19:06 +0100Collected Evidence: Collected Evidence: Restrict certain pesticides A small scale study in the UK found that using the fungicides Propiconazole and Triadimefon reduced chick food insect abundance less than using Pyrazophos. A replicated, controlled trial in Switzerland found that applying metaldehyde slug pellets in a 50 cm band along the field edge adjacent to wildflower strips provided equivalent crop protection to broadcasting the pellets across the whole field.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F565https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F565Fri, 28 Sep 2012 15:37:14 +0100Collected Evidence: Collected Evidence: Translocate owls A small study from New Zealand found that translocating two male boobook Ninox novaeseelandiae novaeseelandiae allowed the establishment of a small population, when they interbred with the last remaining Norfolk Island boobook N. n. undulata A replicated study in the USA found high survival amongst burrowing owls Athene cunicularia translocated as juveniles, although no breeding was recorded and all birds left the release site and were not seen again.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F576https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F576Sun, 30 Sep 2012 14:32:21 +0100Collected Evidence: Collected Evidence: Use techniques to increase the survival of species after capture A small controlled study from the USA found that providing dark, quiet environments with readily-available food and water increased the survival of small birds after capture and increased the probability that they would accept captivity. A study from Hawaii found that keeping birds warm in a ‘mock’ translocation in Hawaii increased survival, although all birds suffered some loss of condition.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F581https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F581Sat, 06 Oct 2012 21:18:18 +0100Collected Evidence: Collected Evidence: Ensure translocated birds are familiar with each other before releaseTwo controlled trials from New Zealand found no evidence that translocating birds which were familiar with each other was more likely to succeed than translocating unfamiliar birds.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F582https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F582Sat, 06 Oct 2012 21:23:28 +0100Collected Evidence: Collected Evidence: Artificially incubate and hand-rear penguins in captivityTwo replicated and controlled studies from South Africa found that hand-reared and released African penguins Spheniscus demersus had similar survival and breeding success as birds which were not orphaned and hand-reared.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F605https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F605Sat, 13 Oct 2012 17:08:04 +0100Collected Evidence: Collected Evidence: Artificially incubate and hand-rear cranes in captivityA replicated and controlled study and a small study, both from the USA, found that hand-reared birds showed normal reproductive behaviour and higher survival than parent-reared birds.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F609https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F609Sat, 13 Oct 2012 17:44:21 +0100Collected Evidence: Collected Evidence: Artificially incubate and hand-rear bustards in captivity A review of a houbara bustard Chlamydotis undulata macqueenii captive breeding programme in Saudi Arabia found that there was no difference in survival between artificially and parentally incubated eggs. A second review of the same programme found that removing eggs from clutches as they were laid increased the number laid by females.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F610https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F610Sat, 13 Oct 2012 17:57:07 +0100Collected Evidence: Collected Evidence: Artificially incubate and hand-rear storks and ibises in captivityA small study in the USA describes the successful artificial incubation and hand-rearing of two Abdim’s stork Ciconia abdimii chicks, whilst a review of northern bald ibis Geronticus eremita conservation found that only very intensive rearing of a small number of chicks appeared to allow strong bonds to form between chicks – thought to be important for the successful release of birds into the wild.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F612https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F612Sun, 14 Oct 2012 11:55:51 +0100Collected Evidence: Collected Evidence: Release captive-bred individuals into the wild to restore or augment wild populations of storks and ibisesA replicated study and a review of northern bald ibis Geronticus eremita release programmes in Europe and the Middle East found that only one of four had resulted in a wild population being established or supported, with many birds dying or dispersing, rather than forming stable colonies.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F624https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F624Sun, 14 Oct 2012 14:38:18 +0100Collected Evidence: Collected Evidence: Release captive-bred individuals into the wild to restore or augment wild populations of owls A study in the USA found that a barn owl Tyto alba population was established following the release of 157 birds in the area over three years. A replicated, controlled study in Canada found that released burrowing owls Athene cunicularia had similar reproductive output, but higher mortality than wild birds, and no released birds returned after migration, although return rates for released birds’ offspring were no different from wild birds.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F627https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F627Sun, 14 Oct 2012 22:47:34 +0100Collected Evidence: Collected Evidence: Use appropriate populations to source released populations A replicated study from Sweden and a small study from France found that birds sourced from populations distant from where they were released were less successful than birds from the area. In Sweden, released white storks Ciconia ciconia from North Africa produced fewer than half the chicks as those that naturally re-colonised, whilst both studies found that storks and little bustards Tetrax tetrax were less likely to migrate than birds originating in the release area.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F631https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F631Sun, 14 Oct 2012 23:16:17 +0100Collected Evidence: Collected Evidence: Use ‘anti-predator training’ to improve survival after release A review from Pakistan and a small trial from Saudi Arabia found that pheasants and bustards had higher survival after release, when given pre-release predator training, compared to birds without training, many of which were predated. The Saudi Arabian study found that introducing a model fox (as opposed to a live predator) to cages did not increase post-release survival. Introducing a live fox to the cage increased post-release survival more than other techniques used.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F637https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F637Sun, 14 Oct 2012 23:49:41 +0100Collected Evidence: Collected Evidence: Sow rare or declining arable weeds Two studies from the UK (both replicated, controlled and randomized) found that the establishment of rare or declining arable weeds depended upon cover crop, cultivation, timing of cut and year or a combination of cultivation in autumn and herbicide treatment.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F642https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F642Tue, 16 Oct 2012 13:52:39 +0100Collected Evidence: Collected Evidence: Restore or create wood pasture One replicated controlled trial in Belgium found that protection from grazing enhanced the survival and growth of tree seedlings planted in pasture. One replicated study in Switzerland found that cattle browsing increased the mortality of tree saplings of four species, and reduced average shoot production and total above-ground biomass. Browsing frequency decreased with increasing height of the surrounding vegetation.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F644https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F644Wed, 17 Oct 2012 15:01:11 +0100Collected Evidence: Collected Evidence: Restore or create upland heath/moorland A small unreplicated trial of heather moorland restoration in northern England found that mowing and flail cutting along with grazing could be used to control the dominance of purple moor grass. The same study found moorland restoration benefited one bird species, with one or two pairs of northern lapwing found to breed in the area of restored moorland, where none had bred prior to restoration. A review from the UK concluded that vegetation changes took place very slowly following the removal of grazing to restore upland grassland to heather moorland.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F650https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F650Tue, 23 Oct 2012 13:03:29 +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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