Collected Evidence: Collected Evidence: Angle windows to reduce collisions by birdsA single randomised, replicated and controlled experiment in the USA found fewer birds collided with windows angled away from the vertical.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F166https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F166Sat, 19 May 2012 20:14:31 +0100Collected Evidence: Collected Evidence: Bury or isolate power lines to reduce incidental bird mortalityA single before-and-after trial in Spain showed a dramatic increase in the survival of juvenile Spanish imperial eagles Aquila adalberti following the burial or isolation of power lines.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F262https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F262Thu, 19 Jul 2012 13:31:11 +0100Collected Evidence: Collected Evidence: Clear or open patches in forests Of nine studies, seven from the UK and the USA found that early-successional species increased in clearcut areas or opened forests, compared to control areas, areas before management, or other management techniques. One study found that population increases only occurred in clearcuts up to 20 ha in size. Two studies report that mature-forest species declined in cut/opened areas of forest. A replicated, randomised, controlled study from the USA found no differences in species richness between clearcuts of different sizes, whilst another American study found that a mosaic of cut and uncut areas supported a variety of species. A long-term study from the USA of a landscape with opened patches found that there were no consistent differences between clearcut and controlled areas, although some species were only seen in clearcuts.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F326https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F326Thu, 26 Jul 2012 16:51:33 +0100Collected Evidence: Collected Evidence: Clearcut and re-seed forests One of two replicated studies from the USA found similar bird densities in clearcut and re-seeded sites as in sites under other managements. A replicated study from the USA found that pine stands replanted with native pines held more scrub-sucessional species than stands managed with tree thinning, midstory tree removal and burning.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F327https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F327Thu, 26 Jul 2012 17:11:04 +0100Collected Evidence: Collected Evidence: Apply herbicide to mid- and understorey vegetation Of seven studies, one replicated, controlled study in forests in Canada found that bird species richness declined after the treatment of deciduous trees with herbicide. Two of the four studies monitoring bird populations (two replicated, controlled before-and-after studies) these found that numbers of red-cockaded woodpeckers or male greater sage grouse increased in all or some herbicide-treated areas. Increases of sage grouse were larger at two areas without vegetation control. One study considered two species: one decreased while the other showed no response. Another found that bird densities increased equally in both control and treatment areas. Three replicated, controlled before-and-after studies in forests found that nest survival was lower where herbicide was applied to exotic shrubs or deciduous vegetation. One study also found lower nesting densities. One controlled study found northern bobwhite chicks higher had foraging success in herbicide-treated forest areas.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F346https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F346Sun, 29 Jul 2012 14:17:01 +0100Collected Evidence: Collected Evidence: Can nest protection increase nest abandonment? A replicated before-and-after study from the USA found that nest abandonment increased after nest exclosures were installed. Two replicated studies in Sweden and the USA found small levels of abandonment, or non-significant increases in abandonment following nest exclosure installation. A meta-analysis from the USA found that some designs of nest exclosures were more likely to lead to abandonment than others.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F401https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F401Thu, 16 Aug 2012 13:41:47 +0100Collected Evidence: Collected Evidence: Can nest protection increase predation of adults and chicks? Three replicated and controlled studies from North America and Sweden found higher levels of predation on adult birds with nest exclosures, one study from Sweden found that predation was no higher. A replicated and controlled study from Alaska found that long-tailed jaegers Stercorarius longicaudus learned to associate exclosures with birds, targeting adult western sandpipers Calidris mauri and quickly predating chicks when exclosures were removed.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F403https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F403Thu, 16 Aug 2012 14:45:33 +0100Collected Evidence: Collected Evidence: Clean birds following oil spills Three studies from South Africa and Australia found high survival of rehabilitated penguins and plovers or similar survival to un-oiled birds. However a large study from the USA and Canada found that rehabilitated common guillemots Uria aalge had significantly lower survival than untreated birds. Three studies from South Africa and Australia found that rehabilitated birds bred, with one finding that rehabilitated birds had similar breeding success to un-oiled birds. However, this study found that birds rehabilitated after a second spill were less likely to breed, whilst two other studies found that rehabilitated birds had lower success than un-oiled birds.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F448https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F448Thu, 23 Aug 2012 16:12:49 +0100Collected Evidence: Collected Evidence: Clean nest boxes to increase occupancy or reproductive success Five studies from Spain and North America found that various songbirds preferentially nested in cleaned nest boxes, compared to used ones. One study from the USA found that eastern bluebirds showed this preference, but most did not switch from a soiled to a cleaned nest box. One study from the USA found that birds showed an avoidance of heavily-soiled boxes and one from Canada found that tree swallows Tachycineta bicolor preferentially selected nests which were sterilised by microwaving. Two studies from the USA found that eastern bluebirds Sialia sialis and house wrens Troglodytes aedon preferentially nested in uncleaned nest boxes, and one study found that prothonotary warblers Protonotaria citrea showed no preference for cleaned or uncleaned boxes. None of the five studies that investigated it found any difference in success or parasitism levels between cleaned and uncleaned nest boxes.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F499https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F499Tue, 04 Sep 2012 16:10:03 +0100Collected Evidence: Collected Evidence: Artificially incubate eggs or warm nests A replicated, controlled trial in the UK found that great tits Parus major were less likely to interrupt their laying sequence if their nest box was heated, although there was no effect on egg or clutch size. A small study in New Zealand found that no kakapo Strigopus habroptilus eggs or chicks died from chilling following the use of nest warmers. Before this a nest had been lost to chilling.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F503https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F503Tue, 04 Sep 2012 16:34:31 +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: Can captive breeding have deleterious effects on individual fitness? Three studies of wild populations, wild and captive populations and museum specimens, one replicated, found evidence for  potentially deleterious physiological or genetic changes due to captive breeding. These studies did not investigate fitness. A study of a wild Mauritius kestrel, Falco punctatus, population derived totally from captive individuals found high inbreeding and a loss of genetic diversity, but this was caused more by the very low population size (four wild birds) than by captivity per se. The museum-based study found reduced relative brain volume in captive wildfowl, compared with wild birds, whilst a comparison of wild and captive populations of white-headed ducks Oxyura leucocephala found lower genetic diversity in captive populations.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F599https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F599Sat, 13 Oct 2012 16:00:16 +0100Collected Evidence: Collected Evidence: Artificially incubate and hand-rear seabirds in captivity Five studies from across the world found evidence for the success of hand-rearing seabirds. One small study in Spain found that one of five hand-reared Audouin’s gulls Larus audouinii successfully bred in the wild. Four studies found that various petrel species (Procellariiformes) successfully fledged after hand-rearing. One controlled study found that fledging rates of hand-reared birds was similar to parent-reared birds, although a study on a single bird found that the chick fledged at a lower weight and later than parent-reared chicks.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F604https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F604Sat, 13 Oct 2012 16:50:42 +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 wildfowl in captivity Two replicated studies in Canada and India found high success rates for hand-rearing buffleheads Bucephala albeola and bar-headed geese Anser indicus in captivity. Eggs were artificially incubated or incubated under foster parents. A replicated, controlled study in England found that Hawaiian geese (nene) Branta sandvicensis chicks showed less well-adapted behaviours if they were raised without parental contact, compared to chicks raised by parents.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F606https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F606Sat, 13 Oct 2012 17:11:00 +0100Collected Evidence: Collected Evidence: Artificially incubate and hand-rear gamebirds in captivityA single, replicated study in Finland found that hand-reared grey partridges Perdix perdix did not take off to fly as effectively as wild-caught birds, potentially making them more vulnerable to predation from ground predators.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F607https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F607Sat, 13 Oct 2012 17:33:47 +0100Collected Evidence: Collected Evidence: Artificially incubate and hand-rear rails in captivityA controlled before-and-after study from New Zealand found that post-release survival of hand-reared takahe Porphyrio hochstetteri (formerly P. mantelli) was as high as wild-reared birds and that six of ten released females raised chicks.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F608https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F608Sat, 13 Oct 2012 17:41:25 +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 waders in captivity Three out of four replicated and controlled studies from the USA and New Zealand found that artificially incubated and/or hand-reared waders had higher hatching and fledging success than controls. One study from New Zealand found that hatching success of black stilt Himantopus novaezelandiae was lower for artificially-incubated eggs.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F611https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F611Sat, 13 Oct 2012 18:03:08 +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: Artificially incubate and hand-rear vultures in captivityA study in Peru found that hand-reared Andean condors Vultur gryphus had similar survival to parent-reared birds after release into the wild.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F613https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F613Sun, 14 Oct 2012 12:01:57 +0100Collected Evidence: Collected Evidence: Artificially incubate and hand-rear raptors in captivity Six studies from across the world found high success rates for artificial incubation and hand-rearing of raptors. A replicated and controlled study from France found that artificially incubated raptor eggs had significantly lower hatching success than parent-incubated eggs. This study found that fledging success for hand-reared chicks was similar to wild chicks, whilst a replicated and controlled study from Canada found that hand-reared chicks had slower growth and attained a lower weight than parent-reared birds. A replicated study from Mauritius found that hand-rearing of wild eggs had higher success than hand-rearing captive-bred chicks. Three studies that provided methodological comparisons found that American kestrel Falco sparverius eggs were more likely to hatch at 38.5oC, compared to 36oC or 40oC, that peregrine falcon F. peregrinus eggs should be incubated over 37oC and that falcon chicks gained far more weight when saline was added to their diet.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F614https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F614Sun, 14 Oct 2012 12:05:10 +0100Collected Evidence: Collected Evidence: Artificially incubate and hand-rear parrots in captivity Two studies from South America describe the successful hand-rearing of parrot chicks, with ten of 12  yellow-shouldered amazons Amazona barbadensis surviving for a year after release and blue-fronted amazons Amazona aestiva fledging at higher weights than wild birds. A review of the kakapo Strigops habroptilus management programme found that chicks could be successfully raised and released, but that eggs incubated from a young age had low success. A study from the USA found that all hand-reared thick-billed parrots Rhynchopsitta pachyrhyncha died within a month of release: significantly lower survival than for wild-caught birds also translocated to the release site.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F615https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F615Sun, 14 Oct 2012 12:29:14 +0100Collected Evidence: Collected Evidence: Artificially incubate and hand-rear songbirds in captivity Four studies from the USA found high rates of success for artificial incubation and hand-rearing of songbirds. The one study to compare techniques found that crow chicks fed more food had higher growth rates, but that these rates never matched those of wild birds.    Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F616https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F616Sun, 14 Oct 2012 12:34:18 +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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