Collected Evidence: Collected Evidence: Control predators not on islandsA single replicated and randomised, paired sites study from the UK found that plots with predator control had increased density and fledgling success of breeding birds.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F384https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F384Wed, 08 Aug 2012 15:17:43 +0100Collected Evidence: Collected Evidence: Control predators not on islands for seabirds A before-and-after study from New Zealand found an increase in a tern population following intensive trapping of invasive mammals. A before-and-after study from Canada found increases in tern fledging success following gull control.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F385https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F385Wed, 08 Aug 2012 16:42:50 +0100Collected Evidence: Collected Evidence: Control predators not on islands for wildfowl Six out of seven studies, mostly from North America found higher reproductive success of ducks when mammalian predators were removed. A before-and-after study found higher survival of captive-bred brown teal Anas chlorotis following feral cat Felis catus control. One meta-analysis from the USA and Canada found that ducks on sites with mammalian predator removal did not have higher reproductive success and trends in reproductive success were no more positive than on sites without predator control.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F386https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F386Wed, 08 Aug 2012 16:53:51 +0100Collected Evidence: Collected Evidence: Control predators not on islands for gamebirds Four controlled studies in Europe found increased populations or productivity of grouse and partridges on sites with predator removal. One study tested multiple interventions simultaneously. A fifth replicated UK study found no increase in grouse densities or reproductive success on sites with gamekeepers, compared to those without.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F387https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F387Wed, 08 Aug 2012 17:25:00 +0100Collected Evidence: Collected Evidence: Control predators not on islands for railsA single study from the USA found more California clapper rails Rallus longirostris obsoletus on sites with higher numbers of foxes removed.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F388https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F388Wed, 08 Aug 2012 17:35:18 +0100Collected Evidence: Collected Evidence: Control predators not on islands for cranesA single trial from the USA found that greater sandhill cranes Grus canadensis tabida had higher hatching and fledging success in years with predator control, compared to years without control.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F389https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F389Wed, 08 Aug 2012 17:37:18 +0100Collected Evidence: Collected Evidence: Control predators not on islands for waders Three out of four controlled studies in the UK and the USA found some evidence for higher reproductive success or lower predation rates for waders in areas or years with predator removal, although one UK study found that only three of six species investigated had increased reproductive success in years with predator removal. Predators removed were carrion crows Corvus corone, gulls Larus spp., red foxes Vulpes vulpes and cats Felis catus.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F390https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F390Wed, 08 Aug 2012 17:40:34 +0100Collected Evidence: Collected Evidence: Control predators not on islands for parrotsA replicated, controlled trial in New Zealand found increased kaka Nestor meridionalis nesting success and lower predation at sites with mammal predator removal than at unmanaged sites.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F391https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F391Thu, 09 Aug 2012 13:05:06 +0100Collected Evidence: Collected Evidence: Control predators not on islands for songbirds A before-and-after study from New Zealand found that a reintroduced population of New Zealand robins Petroica australis declined without predator control and increased with rat poisoning. Two UK studies, one non-experimental, found increased populations of some species following control of bird and mammal predators. One replicated, controlled study from New Zealand found lower New Zealand robin survival in areas where rodent bait was broadcast, but no difference with controls when dispensers were used. Six studies from New Zealand, Australia, UK found increased nest success or survival (in one case with artificial nests) following bird and mammal predator control. One randomised, replicated and controlled study from the USA found no difference in nest survival in a site with mammalian predator removal.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F392https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F392Thu, 09 Aug 2012 13:08:55 +0100Collected Evidence: Collected Evidence: Reduce predation by translocating predatorsTwo studies from France and the USA found local population increases or reduced predationfollowing the translocation of predators away from an area.  A study in Saudi Arabia found that predation was no lower when predators were translocated from the bird release site.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F393https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F393Thu, 09 Aug 2012 13:39:34 +0100Collected Evidence: Collected Evidence: Do birds take bait designed for pest control?Two studies, one randomised, replicated and controlled, from New Zealand and Australia found no evidence that birds took bait meant for pest control.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F395https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F395Thu, 09 Aug 2012 13:47:55 +0100Collected Evidence: Collected Evidence: Reduce nest predation by excluding predators from nests or nesting areasA 2011 systematic review found that excluding predators from nests significantly increased hatching success, although individual barriers around nests sometimes had adverse impacts. See also: Physically protect nests from predators using non-electric fencing; Physically protect nests with individual exclosures/barriers or provide shelters for chicks; Protect bird nests using electric fencing; Use artificial nests that discourage predation; Guard nests to prevent predation; Plant nesting cover to reduce nest predation; Protect nests from ants; Use multiple barriers to protect nests; Use naphthalene to deter mammalian predators; Use snakeskin to deter mammalian nest predators; Play spoken-word radio programs to deter predators; Use 'cat curfews' to reduce predation; Use lion dung to deter domestic cats; Use mirrors to deter nest predators; Use ultrasonic devices to deter cats; Can nest protection increase nest abandonment?; and Can nest protection increase predation of adults and chicks?Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F396https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F396Thu, 09 Aug 2012 14:28:57 +0100Collected Evidence: Collected Evidence: Physically protect nests with individual exclosures/barriers or provide shelters for chicks of ground nesting seabirds A before-and-after study from Japan found an increase in fledging rates of little terns Sterna albifrons following the provision of chick shelters and other interventions. Two studies from the USA and Canada found reduced predation of tern chicks following the provision of chick shelters. A small study from the USA found low levels of use of chick shelters, except when predators were present.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F397https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F397Tue, 14 Aug 2012 13:01:08 +0100Collected Evidence: Collected Evidence: Physically protect nests with individual exclosures/barriers or provide shelters for chicks of waders Three of 13 studies from the USA found higher productivity from nests protected by individual barriers than unprotected nests. Two studies from the USA and Sweden found no higher productivity from protected nests. Eight studies from the USA and Europe found higher hatching rates, or survival, or low predation of nests protected by individual barriers, although two of these found that higher hatching rates did not result in higher productivity. Two small studies from North America found no differences in predation or survival rates between protected and unprotected nests. A meta-analysis from the USA found that there were differences in the effectiveness of different exclosure designs.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F398https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F398Wed, 15 Aug 2012 14:32:17 +0100Collected Evidence: Collected Evidence: Physically protect nests with individual exclosures/barriers or provide shelters for chicks of storks and ibisesA randomised, replicated and controlled study from Cambodia found that giant ibis Thaumatibis gigantean fledgling rates were higher for nests in protected trees than controls.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F399https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F399Thu, 16 Aug 2012 13:10:41 +0100Collected Evidence: Collected Evidence: Physically protect nests with individual exclosures/barriers or provide shelters for chicks of songbirds Three studies from across the world found increased fledging success for nests in trees protected by individual barriers. A replicated controlled study from the USA also found higher success for ground-nests protected by individual barriers. Two studies from the UK and Japan found lower predation rates on nests protected by individual barriers.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F400https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F400Thu, 16 Aug 2012 13:13:40 +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: Use artificial nests that discourage predation Three trials in North America found lower predation or higher nesting success of wildfowl in nest boxes or nesting ‘tubs’ than natural nests in tree cavities or on the ground. A trial in captivity found that raccoons could be prevented from entering nest boxes if they were topped with a metal cone with a 7.6 cm overhang and the distance between entrance hole and the roof was increased from 30 to 60 cm. A replicated study in the USA found that fewer woods duck Aix sponsa used nest boxes with predator guards on when given the choice of unaltered boxes, but that both designs were used with equal frequency when only one design was available.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F402https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F402Thu, 16 Aug 2012 14:40:11 +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: Use multiple barriers to protect nests A replicated, controlled study from the USA found no evidence that erecting an electric fence around nests protected by individual barriers increased fledging success in piping plovers Charadrius melodus. A replicated study from the USA found that removing the outer of two nest protection fences after 15 days appeared to reduce predation compared to when both fences were left for 18 days.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F404https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F404Thu, 16 Aug 2012 15:00:00 +0100Collected Evidence: Collected Evidence: Plant nesting cover to reduce nest predation We found no evidence of planting nesting cover to reduce nest predation for bird populations. '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%2F405https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F405Thu, 16 Aug 2012 15:01:47 +0100Collected Evidence: Collected Evidence: Use snakeskin to deter mammalian nest predatorsA randomised, replicated and controlled trial in the USA found that artificial nests were less likely to be predated if they had snake skin wrapped around them than control nests.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F406https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F406Thu, 16 Aug 2012 15:07:38 +0100Collected Evidence: Collected Evidence: Use mirrors to deter nest predators We found no evidence for the effects of mirrors on nest predation rates. '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%2F407https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F407Thu, 16 Aug 2012 15:09:28 +0100Collected Evidence: Collected Evidence: Use naphthalene to deter mammalian predatorsA replicated, controlled study from the USA found that scattering naphthalene moth balls near artificial nests did not affect predation rates.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F408https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F408Thu, 16 Aug 2012 15:11:27 +0100Collected Evidence: Collected Evidence: Use ultrasonic devices to deter cats We found no evidence for the effects of ultrasonic cat deterrents on bird populations. '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%2F409https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F409Thu, 16 Aug 2012 15:12:26 +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