Collected Evidence: Collected Evidence: Provide artificial nesting sites for divers/loons A replicated before-and-after study from the UK found that there was a very large increase in loon productivity on lakes provided with nesting rafts, with a corresponding increase in productivity across the whole country. Two studies from the USA found higher nesting success on lakes with floating  nesting rafts, compared to sites without rafts, but no new territories were established on lakes without loons but with rafts. A replicated study from the UK found that loons used nesting rafts and artificial islands in some areas of the UK, but not others.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F478https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F478Thu, 30 Aug 2012 14:13:43 +0100Collected Evidence: Collected Evidence: Provide artificial nesting sites for burrow-nesting seabirds Four studies from across the world found evidence for population increases or new populations being established in petrel species following the provision of nest boxes. In two cases nest boxes were combined with the translocation of chicks or other interventions. Six studies from across the world found high occupancy rates for artificial burrows by seabirds, with three finding that occupancy increased over time, taking years to build up. Three studies from across the world found very low occupancy rates for artificial burrows used by petrel species. Eight studies from across the world found that the productivity of birds using artificial burrows was high, in many cases as high or higher than in natural burrows. One replicated study from the USA and a small study from the Galapagos found low productivity of petrels using artificial burrows.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F481https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F481Thu, 30 Aug 2012 16:21:23 +0100Collected Evidence: Collected Evidence: Provide artificial nesting sites for falcons Four studies from the USA and Europe found that local populations of falcons increased following the installation of artificial nesting sites, with one reporting that there was no decline in natural nest use following the installation and use of nest boxes. A replicated study from Canada found that the local population of American kestrels Falco sparverius did not increase following the erection of nest boxes. Eight studies from across the world found that the success and productivity of falcons in nest boxes was high and equal to, or higher than those in natural nests. Four studies from across the world found that productivities in nest boxes were lower than in natural nests or in previously published results, or that some falcons were evicted from their nests by barn owls Tyto alba. Four studies from across the world found no differences in productivity between nest box designs or positions, whilst two, from Spain and Israel found that productivity in boxes varied between designs and habitats. Twenty-one studies from across the world found nest boxes were used by falcons, with one in the UK finding that nest boxes were not used at all. One study from Canada found that falcons preferentially nested in nest boxes over natural nest sites; a study from Mauritius found that most breeding attempts were in nest boxes Four studies found that use increased over time. Seven studies found that position or design affected use, whilst three found no differences between design or positioning.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F489https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F489Mon, 03 Sep 2012 14:01:21 +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: Guard nests to increase nest success A before-and-after study from Costa Rica found an increase in scarlet macaw Ara macau population following the monitoring of nests, along with several other interventions. Two studies from Puerto Rico and New Zealand found that parrot nest success was higher or mortality reduced or nest success higher with intensive monitoring of nests, ompared to periods without monitoring. A study from New Zealand also found high overall nest success when nests were monitored.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F506https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F506Thu, 06 Sep 2012 14:12:26 +0100Collected Evidence: Collected Evidence: Foster eggs or chicks of gannets and boobies with wild conspecificsA small controlled study in Australia found that Australasian gannet chicks Morus serrator were lighter, and hatching and fledging success lower in nests which had an additional egg or chick added. However, overall productivity was (non-significantly) higher in experimental nests.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F507https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F507Thu, 06 Sep 2012 14:17:32 +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 vultures with wild conspecificsTwo small studies, one a New World vulture and one of an Old World species found that single chicks were successfully adopted by foster conspecifics, although in one case this led to the death of one of the foster parents’ chicks.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F509https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F509Thu, 06 Sep 2012 14:34:30 +0100Collected Evidence: Collected Evidence: Foster eggs or chicks of raptors with wild conspecifics Ten out of 11 studies from across the world found that fostering raptor chicks to wild conspecifics had high success rates. A single study from the USA found that only one of six eggs fostered to wild bald eagle Haliaeetus leucocephalus nests were hatched and raised. The authors suggest that the other eggs may have been infertile. A replicated study from Spain found that Spanish imperial eagle Aquila adalberti chicks were no more likely to survive to fledging if they were transferred to foster nests from three chick broods (at high risk from siblicide), compared to chicks left in three-chick broods. A replicated study from Spain found that young (15–20 years old) Montagu's harrier Circus pygargus chicks were successfully adopted, but three older (27–29 day old) chicks were rejected.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F510https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F510Thu, 06 Sep 2012 14:42:31 +0100Collected Evidence: Collected Evidence: Foster eggs or chicks of owls with wild conspecifics A replicated study in the USA found high fledging rates for barn owl Tyto alba chicks fostered to wild pairs. A replicated controlled study from Canada found that captive-reared burrowing owl Athene cunicularia chicks fostered to wild nests did not have significantly lower survival or growth rates than wild chicks.    Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F511https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F511Thu, 06 Sep 2012 15:57:35 +0100Collected Evidence: Collected Evidence: Foster eggs or chicks of cranes with wild conspecificsA small study in Canada found high rates of fledging for whooping crane Grus americana eggs fostered to first time breeders (which normally have very low fertility).  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F512https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F512Thu, 06 Sep 2012 16:13:08 +0100Collected Evidence: Collected Evidence: Foster eggs or chicks of bustards with wild conspecificsA small study in Saudi Arabia found that a captive-bred egg was successfully fostered to a female in the wild.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F513https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F513Thu, 06 Sep 2012 16:18:42 +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: Foster eggs or chicks of parrots with wild conspecifics A replicated study from Venezuela found that yellow-shouldered Amazon Amazona barbadensis chicks had high fledging rates when fostered to conspecific nests in the wild. A second replicated study from Venezuela found significantly lower poaching rates of yellow-shouldered Amazons Amazona barbadensis when chicks were moved to foster nests closer to a field base.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F515https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F515Thu, 06 Sep 2012 16:34:58 +0100Collected Evidence: Collected Evidence: Foster eggs or chicks of petrels and shearwaters with wild non-conspecifics (cross-fostering)A replicated and partially controlled study from Hawaii found that Newell’s shearwater Puffinus newelli eggs fostered to wedge-tailed shearwater P. pacificus nests had high fledging rates.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F516https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F516Thu, 06 Sep 2012 16:54:21 +0100Collected Evidence: Collected Evidence: Foster eggs or chicks of waders with wild non-conspecifics (cross-fostering) A replicated and controlled study from the USA found that killdeer Charadrius vociferus eggs incubated and raised by spotted sandpipers Actitis macularia had similar fledging rates to parent-reared birds. A replicated and controlled study from New Zealand found that cross-fostering black stilt Himantopus novasezelandiae chicks to black-winged stilt H. himantopus nests significantly increased nest success, but that cross-fostered chicks had lower success than chicks fostered to conspecifics’ nests.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F517https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F517Thu, 06 Sep 2012 17:03:55 +0100Collected Evidence: Collected Evidence: Foster eggs or chicks of ibises with wild non-conspecifics (cross-fostering)A 2007 literature review describes attempting to foster northern bald ibis Geronticus eremite chicks with cattle egrets Bubulcus ibis as unsuccessful.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F518https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F518Thu, 06 Sep 2012 17:07:49 +0100Collected Evidence: Collected Evidence: Foster eggs or chicks of cranes with wild non-conspecifics (cross-fostering)Two studies from the USA found low fledging success for cranes fostered to non-conspecifics’ nests.    Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F519https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F519Thu, 06 Sep 2012 17:13:19 +0100Collected Evidence: Collected Evidence: Foster eggs or chicks of songbirds with wild non-conspecifics (cross-fostering) A replicated study from the USA found that the survival of cross-fostered yellow warbler Dendroica petechia chicks was lower than previously-published rates for the species, although incubation and nestling periods were very similar. A replicated and controlled study from Norway found that the success of cross-fostering small songbirds varied depending on the species of chick and foster birds. However, only great tits P. major raised by blue tits P. caeruleus had lower pairing success than control birds, whilst blue tits raised by coal tits P. ater had higher recruitment than controls, or those raised by great tits.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F520https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F520Thu, 06 Sep 2012 17:37:20 +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: Place feeders close to windows to reduce collisionsA randomised, replicated and controlled experiment in the USA found that placing bird feeders close to windows reduced the number of collisions with the windows and the number of fatal collisions.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F557https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F557Sun, 23 Sep 2012 15:13:35 +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: Ensure genetic variation to increase translocation success We did not find any studies on the effects of ensuring genetic variation in translocated 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%2F583https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F583Sat, 06 Oct 2012 21:25:41 +0100Collected Evidence: Collected Evidence: Alter habitat to encourage birds to leave an areaA single before-and-after study in the USA found that an entire Caspian tern Sterna caspia population moved following (amongst other interventions) the alteration of nesting habitat at the old colony site.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F587https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F587Sat, 06 Oct 2012 22:42:09 +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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