Collected Evidence: Collected Evidence: Use artificial visual and auditory stimuli to induce breeding in wild populationsA single small study from the British Virgin Islands found that there was an increase in breeding behaviour in a small population of Caribbean flamingos Phoenicopterus ruber following the introduction of visual and auditory stimulants.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F475https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F475Thu, 30 Aug 2012 12:52:00 +0100Collected Evidence: Collected Evidence: Rehabilitation of injured and treated birds Two replicated studies from the USA and UK found that 40% and 25% of raptors were released following rehabilitation. The USA study also found that 32% of owls were released. Three replicated studies from the USA all found relatively high survival of released raptors, with only 2.4% of birds being recovered (i.e. found dead, 1) and 66–68% survival over two weeks and six weeks. One study found that mortality rates were higher for owls than raptors.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F476https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F476Thu, 30 Aug 2012 13:15:35 +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: Use differently-coloured artificial nestsA replicated study from the USA found that two species showed different colour preferences for nest boxes, but that in each case, the preferred colour had lower nesting success than the less preferred colour.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F500https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F500Tue, 04 Sep 2012 16:21:30 +0100Collected Evidence: Collected Evidence: Repair/support nests to support breedingA small study from Puerto Rico found that nine Puerto Rican parrot Amazona vittata nests were repaired, resulting in no chicks dying of cold.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F502https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F502Tue, 04 Sep 2012 16:31:27 +0100Collected Evidence: Collected Evidence: Remove vegetation to create nesting areas Two out of six studies found that the number of waders and terns nesting in an area increased following the removal of vegetation, and another found that a tern colony moved to an area prepared by removing vegetation. Two of these studies used multiple interventions at once. One study found a decrease in colony size after several interventions, including vegetation control. A study from the UK found that gulls and terns nested in an area cleared of vegetation and a controlled study from Puerto Rico found that although no terns nested in plots cleared completely of vegetation, more nested in partially-cleared plots than in uncleared plots. A before-and-after study from Canada found that tern nesting success was higher after plots were cleared of vegetation and other interventions were used.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F505https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F505Thu, 06 Sep 2012 14:00:49 +0100Collected Evidence: Collected Evidence: Provide supplementary food to allow the rescue of a second chickA small controlled study in Spain found that second chicks from lammergeier Gypaetus barbatus nests survived longer if nests were provided with food, allowing one chick to be rescued.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F541https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F541Sat, 15 Sep 2012 20:58:36 +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%2Fwww.conservationevidence.com%2Factions%2F555https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F555Sat, 22 Sep 2012 20:40:45 +0100Collected Evidence: Collected Evidence: Provide supplementary water to increase survival or reproductive successA controlled study in Morocco found that water supplemented northern bald ibis Geronticus eremite pairs had significantly higher reproductive success than those far from water sources.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F558https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F558Sun, 23 Sep 2012 15:16:43 +0100Collected Evidence: Collected Evidence: Translocate individualsA review of 239 bird translocation programmes found 63–67% resulted in establishment of self-sustaining populations.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F566https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F566Sun, 30 Sep 2012 12:46:30 +0100Collected Evidence: Collected Evidence: Translocate megapodesA replicated study from Indonesia found that up to 78% of maleo Macrocephalon maleo eggs hatched after translocation, with higher success if eggs were reburied as they were found. There was only anecdotal evidence that the translocations increased local populations.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F567https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F567Sun, 30 Sep 2012 12:49:00 +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%2Fwww.conservationevidence.com%2Factions%2F568https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F568Sun, 30 Sep 2012 12:54:24 +0100Collected Evidence: Collected Evidence: Translocate pelicansTwo reviews of a brown pelican Pelecanus occidentalis translocation programme in the USA found high survival of translocated nestlings and that the target population grew enormously, to over 16,000 nests. The authors note that some of the growth may have been due to immigration from the source populations.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F569https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F569Sun, 30 Sep 2012 12:58:02 +0100Collected Evidence: Collected Evidence: Translocate auksA replicated study in the USA and Canada found that 20% of 774 translocated Atlantic puffins Fratercula arctica remained in or near the release site, with up to 7% breeding.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F570https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F570Sun, 30 Sep 2012 13:02:20 +0100Collected Evidence: Collected Evidence: Translocate wildfowl Three studies of two duck translocation programmes in New Zealand and Hawaii found high post-release survival, breeding and the successful establishment of new populations. A replicated study in USA found that none of 391 blue-winged teal Querquedula discors stayed in the release site and that there was high mortality after release. A replicated, controlled study in the USA found that wing-clipping female wood ducks Aix sponsa during translocation prevented them from abandoning their ducklings.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F571https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F571Sun, 30 Sep 2012 13:18:26 +0100Collected Evidence: Collected Evidence: Translocate gamebirds Three studies from the USA found that translocation of gamebirds resulted in population establishment or growth, or an increase in lekking sites. Four studies from the USA found high survival of translocated birds, although one, from Alaska found that translocated birds had high initial mortality, which then fell to levels close to those in resident birds. Two studies from the USA found high mortality in translocated birds. Four studies from the USA found breeding rates that were high, or similar to resident birds, amongst translocated birds.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F572https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F572Sun, 30 Sep 2012 13:50:44 +0100Collected Evidence: Collected Evidence: Translocate rails Three reviews of two translocation programmes in the Seychelles and New Zealand found high survival amongst translocated rails. All studies found that translocated birds bred successfully, although one found that translocated takahe Porphyrio hochstetteri had lower reproductive success than birds in the source population. The other New Zealand study found no differences in breeding success between recently and formerly translocated takahe.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F573https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F573Sun, 30 Sep 2012 13:58:55 +0100Collected Evidence: Collected Evidence: Translocate raptors Six studies of three translocation programmes in the UK and the USA found that all three successfully established populations of white-tailed eagles Haliaeetus albicilla, red kites Milvus milvus and ospreys Pandion halieatus. However, the latest review of the programme to reintroduce red kites to England and Scotland reported that one of six populations was very small, with only four pairs, despite 90 birds being released. A replicated study in Spain found high survival and establishment of translocated Montagu’s harrier Circus pygargus fledglings.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F574https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F574Sun, 30 Sep 2012 14:09:28 +0100Collected Evidence: Collected Evidence: Translocate herons, storks and ibisesA before-and-after study in the USA found that a colony of black-crowned night herons Nycticorax nycticorax was successfully moved, with the new colony producing chicks the year after translocation.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F575https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F575Sun, 30 Sep 2012 14:25:50 +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: Translocate woodpeckers All five translocation programmes studied were for red-cockaded woodpeckers Picoides borealis in the southern USA. Six studies of four programmes found that >50% of translocated birds remained in their new sites, with two studies of the same programme reporting a large population increase. Birds from four programmes were reported as forming pairs or breeding, although some translocated pairs split up and some translocated nestlings were abandoned. One study found that translocated nestlings fledged at similar rates to native chicks.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F577https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F577Sun, 30 Sep 2012 14:34:11 +0100Collected Evidence: Collected Evidence: Translocate parrots Three studies of two translocation programmes from the Pacific and New Zealand found that populations of parrots were successfully established on islands following translocations, including the colonisation of other islands in the New Zealand study. Survival of translocated birds was monitored in five studies of four programmes from across the world and ranged from 41% over 60 days for red-fronted parakeets Cyanoramphus novaezelandiae in New Zealand to 98% for kakapos Strigops habroptila in New Zealand. Survival for translocated thick-billed parrots Rhynchopsitta pachyrhyncha in the USA was higher than for captive-bred birds. Despite very high survival, kakapos that were translocated had very low reproductive output in New Zealand.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F578https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F578Sun, 30 Sep 2012 14:41:44 +0100Collected Evidence: Collected Evidence: Translocate songbirds Nine studies from across the world, including a review of 31 translocation attempts in New Zealand found that translocations led to the establishment of songbird populations. The review found that 79% and 100% of translocation programmes for saddlebacks Philesturnus carunculatus and New Zealand robins Petroica australis, respectively, were successful in establishing populations. Eight of the studies were from islands, mostly following predator removal. Three studies from Zimbabwe, New Zealand and the USA report on three translocation programmes that failed to establish populations. A methodological paper found that the nesting success of saddlebacks decreased as the latitudinal difference between source area and release site increased.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F580https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F580Sat, 06 Oct 2012 12:49:36 +0100Collected Evidence: Collected Evidence: Translocate nests to avoid disturbance Four small trials from the USA and a replicated study from Chatham Island, New Zealand found some success in relocating nests whilst they were in use. However, one study from the USA found that only 40% of burrowing owls Athene cunicularia were moved successfully, another found that American kestrels Falco sparverius tolerated movement of their nest, but not repeated disturbance and another found that barn swallow Hirundo rustica may follow their nest as it is slowly moved on a car, but may not stay at the new site.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F584https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F584Sat, 06 Oct 2012 21:27:21 +0100Collected Evidence: Collected Evidence: Use decoys to attract birds to safe areas Seven studies found that birds bred in areas where decoys (of birds or nests) were used to attract birds. Six of the studies used several interventions at once. Two studies from the USA found that least terns Sterna antillarum and herons were not attracted to new areas to breed when decoys were used. Five studies from North America and France and Spain found that more birds landed near decoys than in control areas. The two studies to compare decoy types found that three-dimensional models were better than two-dimensional ‘cut-outs’ and plastic models of birds were better than rag decoys.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F586https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F586Sat, 06 Oct 2012 22:25:17 +0100
What Works 2021 cover

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.

More about What Works in Conservation

Download free PDF or purchase
The Conservation Evidence Journal

The Conservation Evidence Journal

An online, free to publish in, open-access journal publishing results from research and projects that test the effectiveness of conservation actions.

Read the latest volume: Volume 21

Go to the CE Journal

Discover more on our blog

Our blog contains the latest news and updates from the Conservation Evidence team, the Conservation Evidence Journal, and our global partners in evidence-based conservation.


Who uses Conservation Evidence?

Meet some of the evidence champions

Endangered Landscape ProgrammeRed List Champion - Arc Kent Wildlife Trust The Rufford Foundation Save the Frogs - Ghana Mauritian Wildlife Supporting Conservation Leaders
Sustainability Dashboard National Biodiversity Network Frog Life The international journey of Conservation - Oryx Cool Farm Alliance UNEP AWFA Bat Conservation InternationalPeople trust for endangered species Vincet Wildlife Trust