Collected Evidence: Collected Evidence: Provide specialist advice, assistance preparing conservation plans We have captured no evidence for the effects of providing specialist advice and/or assistance in preparing conservation plans on farmland wildlife. '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%2F114https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F114Mon, 24 Oct 2011 22:14:27 +0100Collected Evidence: Collected Evidence: Provide short grass for wadersA replicated UK study found that common starlings and northern lapwings spent more time foraging on short swards, compared to longer grass, and that starlings captured more prey in short grass.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F221https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F221Tue, 17 Jul 2012 14:03:36 +0100Collected Evidence: Collected Evidence: Provide supplementary foodA replicated, controlled study from Europe found that overall, gardens with supplementary food did not contain more species than those without. However, there was some evidence that gardens with supplementary food in five countries did contain more species than unfed ones, when countries were analysed separately.   For specific interventions see: provide supplementary foodCollected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F521https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F521Sat, 08 Sep 2012 13:18:10 +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%2Fwww.conservationevidence.com%2Factions%2F522https%3A%2F%2Fwww.conservationevidence.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%2Fwww.conservationevidence.com%2Factions%2F523https%3A%2F%2Fwww.conservationevidence.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%2Fwww.conservationevidence.com%2Factions%2F524https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F524Sat, 08 Sep 2012 13:32:31 +0100Collected Evidence: Collected Evidence: Provide supplementary food for gulls, terns and skuas to increase reproductive success Four studies of three experiments from Europe and Alaska found that providing supplementary food increased fledging success or chick survival in two gull species, although a study from the UK found that this was only true for one island, with abnormally low breeding success. A second island with higher success was not affected by feeding. Two of the experiments fed parent birds and one fed the chicks directly. One study from the Antarctic found no effect of feeding parent skuas on productivity. One study from Alaska found increased chick growth when parents were fed; one study from the Antarctic found no increase in chick growth.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F525https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F525Sat, 08 Sep 2012 13:37:48 +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%2Fwww.conservationevidence.com%2Factions%2F527https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F527Sun, 09 Sep 2012 17:34:24 +0100Collected Evidence: Collected Evidence: Provide supplementary food for ibises to increase reproductive successA study from China found that breeding success of crested ibis Nipponia nippon was correlated with the amount of supplementary food provided, although no comparison was made with unfed nests.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F530https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F530Sun, 09 Sep 2012 17:51:49 +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%2Fwww.conservationevidence.com%2Factions%2F533https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F533Sun, 09 Sep 2012 19:15:10 +0100Collected Evidence: Collected Evidence: Provide supplementary food for kingfishers to increase reproductive successA controlled study in the USA found that belted kingfisher Ceryle alcyon supplied with food had heavier nestlings and were more likely to renest. There was mixed evidence for the effect of feeding on laying date.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F534https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F534Sun, 09 Sep 2012 19:30:18 +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%2Fwww.conservationevidence.com%2Factions%2F536https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F536Sun, 09 Sep 2012 19:43:26 +0100Collected Evidence: Collected Evidence: Provide supplementary food for gamebirds to increase adult survival Two European studies found increased numbers of grey partridge Perdix perdix in fed areas, compared to unfed areas. In one study there was no change in the overall population in the study area, in the second there was an increase. One cross-over study from the USA found that northern bobwhites Colinus virginianus had higher overwinter survival in fed areas, one found lower survival and a literature review found no overall effect of feeding.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F544https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F544Sun, 16 Sep 2012 09:01:06 +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%2Fwww.conservationevidence.com%2Factions%2F547https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F547Sun, 16 Sep 2012 09:19:25 +0100Collected Evidence: Collected Evidence: Provide supplementary food for gulls, terns and skuas to increase adult survivalA randomised, replicated and controlled study in the Antarctic found that female south polar skuas Catharacta maccormicki that were fed lost more weight whilst feeding two chicks than unfed birds. There was no difference for birds with single chicks, or male birds.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F548https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F548Sun, 16 Sep 2012 09:21:14 +0100Collected Evidence: Collected Evidence: Provide supplementary food for hummingbirds to increase adult survival Four studies from the USA found that three species of hummingbird showed preferences for higher concentrations of sucrose (measured in weight/volume), consuming more and visiting feeders more frequently. A study from the USA found that black-chinned hummingbirds Archilochus alexanderi preferentially fed on sugar solutions over artificial sweeteners, and that increasing the viscosity of these solutions (so they appeared more like sugar solutions) did not affect their consumption. Two studies from Mexico (ex situ) and Argentina found that four species showed preferences for sucrose over fructose or glucose when equiweight solutions were compared.  One found that birds also preferentially fed on sucrose over a sucrose-glucose mix, the other found no preference for sucrose over a glucose-fructose mix. A controlled study from the USA found that Anna’s hummingbirds Calypte anna showed a preference for red-dyed sugar solutions over five other colours, but only if different colours were presented at the same time. A replicated study from the USA found that rufous hummingbirds Selasphorous rufus preferentially fed on feeders placed higher, over lower ones.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F550https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F550Sun, 16 Sep 2012 09:33:20 +0100Collected Evidence: Collected Evidence: Provide supplementary food for nectar-feeding songbirds to increase adult survival Two studies from Australia and New Zealand found that ten species of honeyeaters and stitchbirds Notiomystis cincta readily used feeders supplying sugar solutions, with seasonal variations varying between species and stitchbirds spending more time foraging for insects when food was supplied. A series of ex situ trials using southern African birds found that most species tested showed a preference for sucrose solutions over glucose or fructose. One study found that sunbirds and sugarbirds only showed such a preference at low (equimolar) concentrations. Two more studies found that two species showed preferences for sucrose when comparing 20% (by weight) solutions, although a third species did not show this preference. All species rejected solutions with xylose (a natural sugar in nectar) added. A final study found that sucrose preferences only became apparent at equicalorific concentrations high enough for birds to subsist on.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F553https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F553Sat, 22 Sep 2012 20:11:36 +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%2Fwww.conservationevidence.com%2Factions%2F639https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F639Sun, 14 Oct 2012 23:54:01 +0100Collected Evidence: Collected Evidence: Provide supplementary food for birds or mammals A total of 18 individual studies investigated the effects of providing supplementary food. Nine studies from France, Sweden and the UK (six replicated studies, of which five controlled and one also randomized and paired) found that the provision of supplementary food increased farmland bird abundance, breeding population size, density, body mass, hatching, nestling growth and fledging rates, increased overwinter survival of a declining house sparrow population and that fed male hen harriers bred with more females than control birds. Two studies did not separate the effects of several other interventions carried out on the same study site. Four studies from the UK and Finland (three replicated studies, of which one controlled and one randomized) found that farmland songbirds and field voles (field voles on unmown plots only) used supplementary food when provided, including the majority of targeted species such as tree sparrow, yellowhammer and corn bunting. Five replicated studies from the UK (of which two also controlled) found that the provision of supplementary food had no clear effect on farmland bird breeding abundance, European turtle dove reproductive success, territory size or territory density, overwinter survival of three stable house sparrow populations, tree sparrow nest box use, or the abundance of weed seeds on the soil surface. One replicated, controlled study from Sweden found no effect of supplementary food provision on common starling clutch size or nestling weight, and lower fledging rates in nests which received supplementary food compared to nests without supplementary food in one year. Four studies from the UK (two replicated of which one was also randomized and controlled) found that the use of supplementary food by farmland birds varied between species and region, depended upon the time of year and proximity to other feeding stations and natural feeding areas. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F648https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F648Thu, 18 Oct 2012 14:20:34 +0100Collected Evidence: Collected Evidence: Provide supplementary food for a certain period of time only One study in Tanzania found that a chimpanzee population increased after supplementary feeding for two months immediately after reintroduction, alongside other interventions. One before-and-after study in Brazil found that a golden lion tamarin population declined after one year following supplementary feeding, alongside other interventions. One study in Brazil found that an abandoned infant muriqui was retrieved by its mother and rejoined the wild group after supplementary feeding, alongside other interventions. Four studies in Brazil, Madagascar, and South Africa found that only a minority of reintroduced primates survived after supplementary feeding, alongside other interventions. One study in Guinea found that the majority of introduced chimpanzees survived for at least 27 months following supplementary feeding, alongside other interventions.. Three studies in Gabon, South Africa and Vietnam found that a majority of primates survived reintroduction while being supplimentry fed alongside other interventions. Two studies in Gabon and the Republic of Congo found that the majority of lowland gorillas survived for at least nine months to four years after provision of supplementary food, alongside other interventions. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1528https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1528Thu, 19 Oct 2017 10:13:06 +0100Collected Evidence: Collected Evidence: Provide suitable bat foraging and roosting habitat at expanding range fronts We found no studies that evaluated the effects of providing suitable bat foraging and roosting habitat at expanding range fronts on bat populations. ‘We found no studies’ means that we have not yet found any studies that have directly evaluated 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%2F2026https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2026Wed, 05 Dec 2018 18:15:42 +0000Collected Evidence: Collected Evidence: Provide supplementary food during/after release of translocated mammals Sixteen studies evaluated the effects of providing supplementary food during/after release of translocated mammals. Four studies were in the UK, two were in each of the USA, France, Australia and Argentina, and one was in each of Italy, Spain, Ireland and South Africa. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (15 STUDIES) Abundance (2 studies): A controlled study in Spain found that providing supplementary food during translocation did not increase European rabbit abundance. A study in France found that following supplementary feeding in a holding pen prior to release, a translocated deer population increased over six years. Reproductive success (4 studies): Three studies (one replicated) in the USA, Italy and Ireland found that having been provided with supplementary food in holding pens prior to release, translocated black-tailed prairie dogs, a pair of Eurasian badgers and most female red squirrels reproduced in the wild. A study in the UK found that some translocated pine martens released from holding pens and then provided with supplementary food and nest boxes bred in the first year after release. Survival (10 studies): Six of 10 studies (including one replicated and one controlled study) in the UK, France, Italy, Ireland, South Africa, USA, Argentina and Australia found that at sites with supplementary food in holding pens before (and in two cases after) release, translocated populations of black-tailed prairie dogs, approximately half of female roe deer and over half of red squirrels, Eurasian badgers, pine martens and released rehabilitated or captive reared giant anteaters survived for between one month and at least two years. Four studies found that at translocation release sites with provision of supplementary food, in most cases artificial refuges and in one case water, no red squirrels, rock hyraxes or burrowing bettongs survived over 2-5 months and most translocated Tipton and Heermann’s kangaroo rat spp. died within five days. A controlled study in France found that translocated European rabbits provided with supplementary food in holding pens for three days prior to release had higher female (but not male) survival rates immediately following release compared to those released directly. A controlled study in the UK found that survival of translocated and rehabilitated European hedgehogs that were provided with supplementary food after release varied with release method. Condition (2 studies): One of three studies (including one replicated, one controlled and two before-and-after studies) in the UK and Australia found that translocated common dormice gained weight after being provided with supplementary food. One found that translocated eastern bettongs did not have increased body weights after provision of supplementary food in fenced enclosures prior to release. The other found that translocated and rehabilitated European hedgehogs provided with food after release all lost body mass, with effects varying with release method. BEHAVIOUR (2 STUDIES) Use (1 study): A controlled study in Australia found that supplementary feeding stations were visited by translocated burrowing bettongs. Behaviour change (1 study): A controlled study in Argentina found that after being provided with supplementary food and kept in holding pens, released captive-bred giant anteaters were less nocturnal than wild-born rehabilitated and released individuals. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2470https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2470Wed, 03 Jun 2020 14:59:22 +0100Collected Evidence: Collected Evidence: Provide supplementary food after fire One study evaluated the effects on mammals of providing supplementary food after fire. This study was in the USA. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (1 STUDY) Survival (1 study): A replicated, randomized, controlled study in the USA found that supplementary feeding did not increase survival of hispid cotton rats following prescribed fire. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2494https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2494Thu, 04 Jun 2020 15:06:37 +0100Collected Evidence: Collected Evidence: Provide supplementary food during/after release of captive-bred mammals Fifteen studies evaluated the effects of providing supplementary food during/after release of captive-bred mammals. Four studies were in Australia, two were in each of the USA, China and Argentina, and one was in each of Poland, the UK, Oman and Saudi Arabia. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (14 STUDIES) Abundance (5 studies): Four studies (one replicated, one before-and-after study) and one review in Poland, Oman, China and Australia found that following provision of supplementary food (and in one case water) to released captive-bred animals, populations of European bison increased more than six-fold over 20 years, Arabian oryx increased over 14 years, eastern-barred bandicoots increased for the first five years before declining, Père David's deer increased more than six-fold over 12 years and Przewalski’s horses (enclosed in winter) increased over 11 years. Reproductive success (9 studies): Eight studies (including two replicated and one before-and-after study) and one review in Poland, the UK, China, the USA, Australia and Saudi Arabia found that following the provision of supplementary food (and in one case water or artificial nests) after release of captive-bred animals, some from holding pens, European bison, European otters, Père David's deer, eastern-barred bandicoots, Przewalski’s horses and some captive-bred red wolves successfully reproduced, Arabian gazelles started breeding in the year following releases and sugar gliders established a breeding population. Survival (6 studies): Four of six studies (one controlled, before-and-after study) in the UK, USA, Argentina and Australia found that following the provision of supplementary food (and in one case water or nest boxes) after release of captive-bred animals, many from holding pens, 19% of red wolves survived for at least seven years, Eurasian otters survived for at least two years, over half the giant anteaters (some rehabilitated) survived for at least six months and hare-wallabies survived at least two months. Two of the studies found that red-tailed phascogales survived for less than a year and most Mexican wolves survived less than eight months. BEHAVIOUR (1 STUDY) Behaviour change (1 study): A controlled study in Argentina found that after being provided with supplementary food and kept in holding pens, released captive-bred giant anteaters were less nocturnal in their activity patterns than released wild-born rehabilitated individuals. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2527https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2527Mon, 08 Jun 2020 14:23:58 +0100Collected Evidence: Collected Evidence: Provide supplementary feed to reduce tree damage One study evaluated the effects of providing supplementary feed on the magnitude of tree damage caused by mammals. This study was in USA. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (0 STUDIES) OTHER (1 STUDY) Human-wildlife conflict (1 study): A replicated, randomized, paired sites, controlled, before-and-after study in USA found that supplementary feeding reduced tree damage by black bears. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2629https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2629Fri, 12 Jun 2020 12:41:42 +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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