Collected Evidence: Collected Evidence: Mark or tint windows to reduce collision mortality Two randomised, replicated and controlled studies (one ex situ) found that marking windows did not appear to reduce bird collisions. However, when windows were largely covered with white cloth, fewer birds flew towards them. A randomised, replicated and controlled study found that fewer birds collided with tinted windows than with un-tinted ones, although the authors noted that the poor reflective quality of the glass could have influenced the results. Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F167https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F167Sat, 19 May 2012 20:22:28 +0100Collected Evidence: Collected Evidence: Control mammalian predators on islands for pigeonsTwo before-and-after trials on Mauritius found that fewer pink pigeon Columba mayeri nests were predated and more chicks were fledged following systematic and intensive rat control.  Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F380https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F380Wed, 08 Aug 2012 14:19:04 +0100Collected Evidence: Collected Evidence: Reduce inter-specific competition for food by removing or controlling competitor species Two controlled before-and-after studies from the UK found that six species of wildfowl showed significant increases following the removal of fish from lakes. Three other species did not show increases. A study from France found that grey partridges Perdix perdix increased at a site with several interventions, including the control of competitor species. A before-and-after study from Spain found no change in the rate of kleptoparasitic attacks on herons after the culling of gulls at a colony.  Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F428https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F428Fri, 17 Aug 2012 17:54:16 +0100Collected Evidence: Collected Evidence: Restrict certain pesticides or other agricultural chemicals for birdsA small scale study found that Pyrazophos reduced chick food abundance more than other foliar fungicides. A before-and-after study from Spain found that the population of griffon vultures Gyps fulvus increased in the study area following multiple interventions including the banning of strychnine.  Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F455https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F455Wed, 29 Aug 2012 14:24:27 +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%2Fconservationevidencejournal.com%2Factions%2F507https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F507Thu, 06 Sep 2012 14:17:32 +0100Collected Evidence: Collected Evidence: Provide supplementary food for petrels to increase reproductive successA replicated controlled study in Australia found that Gould’s petrel Pterodroma leucoptera chicks provided with supplementary food had very similar fledging rates to both control and hand-reared birds, but were significantly heavier than other birds.  Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F522https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F522Sat, 08 Sep 2012 13:22:09 +0100Collected Evidence: Collected Evidence: Provide supplementary food for gannets and boobies to increase reproductive success A small controlled study in Australia found that Australasian gannet Morus serrator chicks were significantly heavier if they were supplied with supplementary food, but only in one of two years. Fledging success of fed nests was also higher, but not significantly so. A randomised replicated and controlled study in the Galapagos Islands found that fed female Nazca boobies Sula granti were more likely to produce two-egg clutches if they were fed, and that second eggs were significantly heavier.  Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F523https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F523Sat, 08 Sep 2012 13:25:20 +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%2Fconservationevidencejournal.com%2Factions%2F524https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F524Sat, 08 Sep 2012 13:32:31 +0100Collected Evidence: Collected Evidence: Provide supplementary food for wildfowl to increase reproductive successA small randomised and controlled ex situ study from Canada found faster growth and higher weights for fed greater snow goose Chen caerulescens atlantica chicks than unfed ones, but no differences in mortality rates.  Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F526https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F526Sun, 09 Sep 2012 17:16:26 +0100Collected Evidence: Collected Evidence: Provide supplementary food for gamebirds to increase reproductive successA controlled study in Tibet found that Tibetan eared pheasants Crossoptilon harmani that were fed supplementary food laid significantly larger eggs and clutches than control birds. Nesting success and laying dates were not affected.  Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F527https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F527Sun, 09 Sep 2012 17:34:24 +0100Collected Evidence: Collected Evidence: Provide supplementary food for rails and coots to increase reproductive success A small randomised and controlled trial in the USA found that fed American coots Fulica americana laid heavier eggs, but not larger clutches than controls. However, a randomised, replicated and controlled study in Canada found that clutch size, but not egg size was larger in fed American coot territories. There was also less variation in clutch size between fed territories. The Canadian study also found that coots laid earlier when fed, whilst a replicated cross-over trial from the UK found three was a shorter interval between  common moorhens Gallinula chloropus clutches in fed territories, but that fed birds were no more likely to produce second broods.  Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F528https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F528Sun, 09 Sep 2012 17:37:36 +0100Collected Evidence: Collected Evidence: Provide supplementary food for vultures to increase reproductive success Two before-and-after studies from the USA and Greece found that there were population increases in local populations of two vultures (one New World, one Old World) following the provision of food in the area. A study from Israel found that a small, regularly supplied feeding station could provide sufficient food for breeding Egyptian vultures Neophron percnopterus. A before-and-after study from Italy found that a small population of Egyptian vultures Neophron percnopterus declined following the provision of food at a feeding station, and only a single vulture was seen at the feeding station.  Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F531https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F531Sun, 09 Sep 2012 18:08:42 +0100Collected Evidence: Collected Evidence: Provide supplementary food for owls to increase reproductive success Two replicated and controlled trials from Europe and the USA found that owls supplied with supplementary food had higher hatching and fledging rates than control pairs. The European study, but not the American, also found that fed pairs laid earlier  and had larger clutches The American study also found that owls were no more likely to colonise nest boxes provided with supplementary food.  Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F533https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F533Sun, 09 Sep 2012 19:15:10 +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%2Fconservationevidencejournal.com%2Factions%2F536https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F536Sun, 09 Sep 2012 19:43:26 +0100Collected Evidence: Collected Evidence: Provide supplementary food for wildfowl to increase adult survival Two studies from Canada and Northern Ireland found that five species of wildfowl readily consumed supplementary food (grains and seeds). Only the Canadian study assessed the physiological effects of feeding, and found that fed birds were heavier and had larger hearts or flight muscles or had more body fat than controls  Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F542https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F542Sun, 16 Sep 2012 08:47:27 +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%2Fconservationevidencejournal.com%2Factions%2F545https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F545Sun, 16 Sep 2012 09:10:04 +0100Collected Evidence: Collected Evidence: Provide supplementary food for raptors to increase adult survivalTwo randomised, replicated and controlled studies in the USA found that nesting northern goshawks Accipiter gentilis were significantly heavier in territories supplied with supplementary food, compared with those from unfed territories.  Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F546https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F546Sun, 16 Sep 2012 09:12:47 +0100Collected Evidence: Collected Evidence: Provide supplementary food for cranes to increase adult survivalA before-and-after study from Japan and a global literature review found that local crane populations increased after the provision of supplementary food.  Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F547https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F547Sun, 16 Sep 2012 09:19:25 +0100Collected Evidence: Collected Evidence: Provide supplementary food for pigeons to increase adult survival A study of a recently-released pink pigeon Nesoenas mayeri population on Mauritius found that fewer than half the birds used supplementary food, and appeared to survive without it. However, a later study of the population found that almost all birds were recorded using supplementary feeders.  Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F549https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F549Sun, 16 Sep 2012 09:24:17 +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%2Fconservationevidencejournal.com%2Factions%2F551https%3A%2F%2Fconservationevidencejournal.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%2Fconservationevidencejournal.com%2Factions%2F554https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F554Sat, 22 Sep 2012 20:37:07 +0100Collected Evidence: Collected Evidence: Provide supplementary food through the establishment of food populations One pre-1950 study in the USA found that waterfowl fed on specially-planted rye grass. Three studies from North America and Sweden found that attempts to support populations by establishing prey did not succeed. Whooping cranes Grus americana in the USA preferentially fed on scattered grains, over planted crops; attempts in Sweden to boost macroinvertebrate numbers were not successful and great horned owls Bubo virginianus in Canada did not respond to induced increases in prey populations.  Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F555https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F555Sat, 22 Sep 2012 20:40:45 +0100Collected Evidence: Collected Evidence: Translocate petrels and shearwatersTwo studies from Australia and one from New Zealand found that colonies of burrow-nesting Procellariiformes were successfully established on two islands, and in uninhabited areas of another following the translocation and hand-rearing of chicks.  Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F568https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F568Sun, 30 Sep 2012 12:54:24 +0100Collected Evidence: Collected Evidence: Release captive-bred individuals into the wild to restore or augment wild populations of wildfowl Two studies of reintroduction programmes of ducks in New Zealand found high survival of released birds and population establishment, with one describing successful breeding. One study describes higher success in the second year of the release programme, potentially because there was then a population present in the wild and more intensive predator control. A before-and-after study from Alaska found low survival of released cackling geese Branta hutchinsii, but that the population recovered from 1,000 to 6,000 birds after releases and the control of mammalian predators. A review of a reintroduction programme from Hawaii found that the release of 2,150 Hawaiian geese (nene) Branta sandvicensis had not resulted in the establishment of a self-sustaining population, although some birds bred. Two studies from Canada found very low return rates for released ducks with one finding no evidence for survival of released birds over two years, although there was some evidence that breeding success was higher for released birds than wild ones. Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F618https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F618Sun, 14 Oct 2012 13:05:11 +0100Collected Evidence: Collected Evidence: Provide supplementary food after release Three studies from found that malleefowl Leipoa ocellata, Andean condors Vultur gryphus and pink pigeons Nesoenas mayeri used supplementary food when it was provided after release. A replicated, controlled study from Australia found that malleefowl had higher survival when supplied with supplementary food. A study in Peru found that supplementary food could be used to increase the foraging range of condors after release, or to guide them back to suitable feeding areas.  Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F639https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F639Sun, 14 Oct 2012 23:54:01 +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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