Collected 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 vocalisations to attract birds to safe areas Six studies from North America, the Galapagos and the Azores found that seabirds were more likely to nest in areas where vocalisations were played, or were successfully attracted to nest in new areas, following the playing of vocalisations. Four of these studies used several interventions at once. One study found that some calls were more effective than others. Two studies from the USA and the Galapagos found that birds did not colonise all new areas where vocalisations were played. It is possible that the result from the Galapagos was due to only having a single year’s data. One controlled study from Hawaii found that albatross were more likely to land in areas where vocalisations were played than in areas without vocalisation playback. A small controlled study from New Zealand found that terns were not more likely to land in areas where vocalisations were played.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F585https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F585Sat, 06 Oct 2012 21:54:59 +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 +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 +0100Collected Evidence: Collected Evidence: Use captive breeding to increase or maintain populations of tinamousA replicated study from Costa Rica over three years found that great tinamous Tinamus major successfully bred in captivity, with similar reproductive success to wild birds.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F588https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F588Sat, 06 Oct 2012 22:48:42 +0100Collected Evidence: Collected Evidence: Use captive breeding to increase or maintain populations of seabirdsA study from Spain over five years found that a single pair of Audouin’s gulls, Larus audouinii, successfully bred in captivity.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F589https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F589Sat, 06 Oct 2012 22:52:51 +0100Collected Evidence: Collected Evidence: Use captive breeding to increase or maintain populations of railsA study from an island in Australia found that Lord Howe Island woodhens Tricholimnas sylvestris successfully bred in captivity, with 66 chicks being produced over four years from three pairs of adults.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F590https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F590Sat, 06 Oct 2012 22:55:27 +0100Collected Evidence: Collected Evidence: Use captive breeding to increase or maintain populations of cranesA study from Canada over 32 years found that whooping cranes Grus americana successfully bred in captivity eight years after the first eggs were removed from the wild. The authors note that young ‘downy’ chicks suffered high mortality in captivity.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F591https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F591Sat, 06 Oct 2012 22:58:51 +0100Collected Evidence: Collected Evidence: Use captive breeding to increase or maintain populations of bustards We captured four studies of a houbara bustard, Chlamydotis undulata, macqueenii captive breeding programme in Saudi Arabia. The project successfully raised chicks in captivity, with 285 chicks hatched in the 7th year of the project after 232 birds were used to start the captive population. Captive birds bred earlier and appeared to lay more eggs than wild birds. Forty-six percent of captive eggs hatched and 43% of chicks survived to ten years old, although no comparison was made with wild birds.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F592https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F592Sat, 06 Oct 2012 23:13:15 +0100Collected Evidence: Collected Evidence: Use captive breeding to increase or maintain populations of storks and ibises We captured a small study and a review describing the captive breeding of storks (Ciconiidae) and a study and a review describing the breeding of northern bald ibis, Geronticus eremita. Both studies on storks were from the USA. The small study found that a pair bred; the review found that only seven of 19 species had been successfully bred in captivity. A review of bald ibis conservation found that 1,150 birds had been produced in captivity from 150 founders over 20 years. However, some projects had failed, and a study from Turkey found that captive birds had lower productivity than wild birds.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F595https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F595Sat, 13 Oct 2012 14:54:55 +0100Collected Evidence: Collected Evidence: Use captive breeding to increase or maintain populations of raptors Three small studies and a review from around the world all found that raptors bred successfully in captivity. Two small studies on Accipiter spp. found that wild-caught birds bred in captivity after a few years, with one pair producing 15 young over four years, whilst a study on bald eagle, Haliaeetus leucocephalus, captive breeding found low fertility in captive-bred eggs, but that birds still produced chicks after a year or so together. A review of Mauritius kestrel, Falco punctatus, captive breeding found that 139 independent young were raised over 12 years from 30 eggs and chicks taken from the wild (of which 13 survived). An update of the same programme found that hand-reared Mauritius kestrels were less successful if they came from captive-bred eggs, compared to wild ‘harvested’ eggs.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F596https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F596Sat, 13 Oct 2012 15:08:20 +0100Collected Evidence: Collected Evidence: Use captive breeding to increase or maintain populations of pigeonsA review of a captive-breeding programme on Mauritius and in the UK found that 42 pink pigeons, Nesoenas mayeri, were successfully bred in captivity.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F597https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F597Sat, 13 Oct 2012 15:21:33 +0100Collected Evidence: Collected Evidence: Use captive breeding to increase or maintain populations of songbirds A replicated study from Australia and two small studies from the USA found that three species of songbird were successfully bred in captivity. Four out of five pairs of wild-bred, hand-reared puaiohi, Myadestes palmeri, formed pairs and laid a total of 39 eggs in 1998 and a breeding population of helmeted honeyeaters, Lichenostomus melanops cassidix, was successfully established through a breeding programme. Only one pair of loggerhead shrikes, Lanius ludovicianus, formed pairs from eight wild birds caught and their first clutch died.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F598https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F598Sat, 13 Oct 2012 15:24:35 +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: Use artificial insemination in captive breeding A review of artificial insemination argued that it could be a useful tool to conservationists, but that there were challenges to its use. Deep and repeated inseminations increased fertility. Two trials from the USA found that artificial insemination of raptors achieved approximately 50% fertility or 0%. A review of a houbara bustard Chlamydotis undulata macqueenii captive breeding programme in Saudi Arabia found that artificial insemination increased fertility, whilst another review found that the highest fertility levels were achieved with inseminations of at least 10 million spermatozoa every 4–5 days.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F601https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F601Sat, 13 Oct 2012 16:16:19 +0100Collected Evidence: Collected Evidence: Freeze semen for use in artificial insemination A small controlled trial in the USA found that using frozen semen for artificial insemination resulted in lower fertility in falcons, and a second small trial from the USA found that an American kestrel Falco sparverius had only 33% fertility when inseminated with frozen semen. A small trial from the USA found that fertility rates were highest when semen contained 10% dimethyl sulphoxide (DMSO, a cryoprotectant), compared to semen containing 6% or 8% DMSO.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F602https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F602Sat, 13 Oct 2012 16:27:01 +0100Collected Evidence: Collected Evidence: Wash contaminated semen and use it for artificial inseminationA single replicated controlled study in Spain found that semen contaminated with urine could be successfully washed to increase its pH and produced three raptor nestlings.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F603https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F603Sat, 13 Oct 2012 16:47:48 +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 +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