Collected Evidence: Collected Evidence: Asian clams: Add chemicals to the water A replicated laboratory study in the USA found that dosing with the biocides chlorine, potassium and copper killed Asian clams. A controlled, replicated laboratory study and a controlled, replicated field study in the USA found that higher concentrations of chlorine and bromine, delivered at higher temperatures, shortened the time required to kill the Asian clams. A controlled field-based trial in Spanish irrigation systems showed that fat-coated particles called BioBullets could kill 100% of the Asian clams within pipes. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1118https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1118Tue, 13 Oct 2015 14:59:51 +0100Collected Evidence: Collected Evidence: Water primrose: Chemical control using herbicides A controlled, replicated laboratory study in the USA found that the herbicide triclopyr TEA applied at concentrations of 0.25% killed 100% of young cultivated water primrose within two months. A before-and-after field study in the UK found that the herbicide glyphosate controlled water primrose, causing 97% mortality when mixed with a non-oil based sticking agent and 100% mortality when combined with TopFilm. A controlled, replicated, randomized study in Venezuela3, found that use of the herbicide halosulfuron-methyl (Sempra) resulted in a significant reduction in water primrose coverage without apparent toxicity to rice plants. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1139https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1139Tue, 13 Oct 2015 16:14:37 +0100Collected Evidence: Collected Evidence: Crassula helmsii: Use salt water to kill plants Two replicated, controlled container trials and two before-and-after field trials in the UK found that seawater eradicated Crassula helmsii.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1288https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1288Tue, 12 Jul 2016 09:14:42 +0100Collected Evidence: Collected Evidence: Primates: Present food in puzzle feeders Two before-and-after studies in the USA and the UK found that the use of puzzle feeders decreased food sharing, increased foraging behaviour, and the use of tools but also aggression. One replicated, before-and-after study in the USA found that the use of puzzle feeders increased time spent feeding and less time inactive.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1318https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1318Wed, 12 Oct 2016 14:51:50 +0100Collected Evidence: Collected Evidence: Crop production: Plant flowersCrop yield (2 studies): One replicated, controlled study from Spain found higher crop yields in coriander plants next to planted flower strips, compared to coriander plants next to unplanted field margins. One replicated, randomized, controlled study from Italy found higher crop yields in tomatoes next to planted flower strips, compared to tomatoes next to bare ground, in some comparisons. Crop quality (0 studies) Implementation options (3 studies): One replicated, randomized, controlled study from the USA found smaller lettuces in fields planted with flowers, in five out of six configurations. One replicated, controlled study from Spain found higher coriander yields next to field margins planted with more flower species, compared to fewer flower species. One replicated, randomized, controlled study from Italy found lower crop yields in tomatoes next to field margins planted with more flower species, compared to fewer flower species, in some comparisons.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1360https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1360Fri, 05 May 2017 15:10:52 +0100Collected Evidence: Collected Evidence: Water: Add sewage sludge to the soilWater use (0 studies) Water availability (2 studies): One replicated, controlled study from Spain found less runoff from plots with added sewage sludge, compared to plots without it, in one of four comparisons. One replicated, controlled study from the USA found similar amounts of water in soils with or without added sewage sludge. Pathogens and pesticides (0 studies) Nutrients (1 studies): One replicated, randomized, controlled study from Portugal found that more nitrate was leached from soils with added sewage sludge, compared to soils without it, in some comparisons. Sediments (0 studies) Implementation options (1 study): One replicated, controlled study from Portugal found that more nitrate was leached from plots with a split application of sewage sludge, but not with a single application, compared to plots without added sewage sludge.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1379https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1379Mon, 15 May 2017 15:23:14 +0100Collected Evidence: Collected Evidence: Pest regulation: Add compost to the soilPest regulation (2 studies): Of two replicated, randomized, controlled studies from the USA and an unspecified Mediterranean country, one study found less disease in crops grown in soils with added compost, compared to soils without it, in some comparisons, but one study found no differences in most crop diseases. One replicated, controlled study from the USA found similar amounts of Escherichia coli bacteria in plots with or without added compost. This study also found that similar percentages of pests were consumed by natural enemies in plots with or without added compost. Crop damage (1 study): One replicated, randomized, controlled study found fewer dead tomato plants in soil with added compost, compared to soil without added compost, in some comparisons. Ratio of natural enemies to pests (1 study): One replicated, controlled study from the USA found similar ratios of natural enemies to pests (mostly aphids) in plots with or without added compost. Pest numbers (1 study): One replicated, controlled study from the USA found similar pest numbers in plots with or without added compost. Natural enemy numbers (0 studies)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1392https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1392Mon, 15 May 2017 16:13:04 +0100Collected Evidence: Collected Evidence: Pest regulation: Plant hedgerowsPest regulation (1 study): One replicated, paired, site comparison from the USA found that a higher proportion of pest eggs were parasitized in tomato fields with hedgerows, compared to fields with weedy edges, but only up to 100 m into the crop. Crop damage (1 study): One replicated, paired, site comparison from the USA found that pest damage to tomatoes was no different in fields with hedgerows than it was in fields with weedy edges. Ratio of natural enemies to pests (2 studies): Of two replicated site comparisons from the USA, one paired study found a greater ratio of natural enemies to pests in hedgerows, compared to weedy edges, but one unpaired study did not. The unpaired study also found no difference in the ratio of natural enemies to pests between fields with hedgerows and fields with weedy edges. Pest numbers (1 study): One replicated, paired, site comparison from the USA found fewer pests in fields or field edges with hedgerows, compared to fields or field edges without hedgerows. Natural enemy numbers (1 study): One replicated, paired, site comparison from the USA found more natural enemies in fields with hedgerows, compared to fields with weedy edges, and in hedgerows themselves, compared to weedy edges, in some comparisons.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1401https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1401Fri, 19 May 2017 09:15:42 +0100Collected Evidence: Collected Evidence: Other biodiversity: Plant or maintain ground cover in orchards or vineyardsAmphibians (0 studies) Birds (1 study): One site comparison from Spain found more birds and higher bird diversity in a vineyard with resident vegetation (without tillage), compared to a vineyard with bare soil (with conventional tillage), between the vine rows. Invertebrates (0 studies) Fungi (1 study): One replicated, randomized, controlled study from Portugal found more mushrooms and mushroom species in plots with cover crops (without tillage), compared to plots without cover crops (with conventional tillage). Mammals (0 studies) Plants (0 studies) Reptiles (0 studies) Implementation options (3 studies): One site comparison from Spain found more birds and higher bird diversity in a vineyard with mown resident vegetation, compared to a vineyard with herbicide-treated resident vegetation, between the vine rows. One replicated, randomized, controlled study from Portugal found fewer mushrooms and fewer mushroom species, but similar mushroom diversity, in plots with seeded cover crops, compared to resident vegetation. One replicated site comparison from Greece found more flowering plant species, and higher flowering plant cover, in managed orchards, compared to abandoned orchards.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1413https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1413Fri, 19 May 2017 09:47:59 +0100Collected Evidence: Collected Evidence: Other biodiversity: Plant flowersAmphibians (0 studies) Birds (0 studies) Invertebrates (0 studies) Mammals (0 studies) Plants (2 studies): One replicated, paired, controlled study from Italy found similar numbers of plant species in planted flower strips and unplanted field margins, but found higher plant diversity in unplanted margins. One replicated study from the USA found that most flower species persisted for at least two years after planting. Reptiles (0 studies) Implementation options (2 studies): One replicated study from the USA found that more plant species persisted in flower strips when twice as many seeds were sown, but there was no further increase in persistence at higher seeding rates. One replicated, randomized, controlled study from Spain found that tillage had inconsistent effects on the emergence of planted flowers.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1414https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1414Fri, 19 May 2017 09:50:10 +0100Collected Evidence: Collected Evidence: Other biodiversity: Plant hedgerowsAmphibians (0 studies) Birds (0 studies) Invertebrates (0 studies) Mammals (0 studies) Plants (1 study): One replicated, paired site comparison from the USA found no difference in the number of flower species in hedgerows, compared to weedy field edges. Reptiles (0 studies) Implementation options (2 studies): One replicated site comparison from the USA found more plant species in narrow hedgerows, compared to wide hedgerows, and higher plant cover in younger hedgerows, compared to older hedgerows. One replicated site comparison from the USA found higher cover of exotic plants, compared to native plants, in young hedgerows, but not in old hedgerows.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1415https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1415Fri, 19 May 2017 09:51:59 +0100Collected Evidence: Collected Evidence: Remove and relocate ‘problem’ animals One replicated, before-and-after study in India found that ‘problem’ rhesus monkeys that were translocated, alongside other interventions, survived and remained at the release sites for at least four years. One controlled, before-and-after study in Kenya found that after 16 years, most crop-raiding olive baboons that were translocated from farmland, alongside other interventions, had survived and had similar survival rates compared to non-translocated populations. One before-and-after, site comparison study in the Republic of Congo and Gaboon found that 84% of the ‘problem’ western lowland gorillas that were relocated, alongside other interventions, survived for at least four years. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1422https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1422Tue, 17 Oct 2017 09:04:32 +0100Collected Evidence: Collected Evidence: Install rope or pole (canopy) bridges One study in Brazil found that black lion tamarins and capuchins used a pole bridge to cross a road. One before-and-after study in Belize found that a black howler monkey population increased after the construction of pole bridges over man-made gaps. One before-and-after study in Madagascar found that all six monitored lemur species used bridges to cross roads and pipelines. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1457https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1457Tue, 17 Oct 2017 13:28:40 +0100Collected Evidence: Collected Evidence: Regularly de-activate/remove ground snares One before-and-after study in the Democratic Republic of Congo and Rwanda found that mountain gorilla numbers increased over five years in an area that was patrolled for snares, alongside other interventions. One before-and-after study in the Democratic Republic of Congo, Rwanda and Uganda found that a mountain gorilla population declined in an area where snares were removed regularly, alongside other interventions. One before-and-after study in Ghana found that the number of snares declined in an area where they were regularly removed, alongside other interventions. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1475https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1475Tue, 17 Oct 2017 17:15:09 +0100Collected Evidence: Collected Evidence: Provide better equipment (e.g. guns) to anti-poaching ranger patrols One before-and-after study in the Democratic Republic of Congo and Rwanda found that gorilla populations increased after anti-poaching guard were provided with better equipment, alongside other interventions. One study in Uganda found that no gorillas were killed for 21 months after game guards were provided with better equipment, alongside other interventions. One before-and-after study in Rwanda found that the number of immature gorillas increased and the number of snares decreased after anti-poaching patrols were supplied with better equipment, alongside other interventions. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1476https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1476Tue, 17 Oct 2017 17:22:29 +0100Collected Evidence: Collected Evidence: Implement community control of patrolling, banning hunting and removing snares A site comparison study in the Democratic Republic of Congo found that community control was more effective at reducing illegal bushmeat hunting, including primates, compared to the nearby national park. A before-and-after study in Cameroon found that no incidents of gorilla poaching occurred over three years after implementation of community control and monitoring of illegal activities. A site comparison study in Nigeria found that there were more gorillas and chimpanzees in an area managed by a community conservation organisation than in areas not managed by local communities. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1482https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1482Tue, 17 Oct 2017 19:12:50 +0100Collected Evidence: Collected Evidence: Use selective logging instead of clear-cutting One site comparison in Sierra Leone found that primate densities were higher in forest that had been logged at low intensity than in a forest logged at high intensity. One before-and-after study in Madagascar found that the number of lemurs increased following selective logging. One site comparison study in Uganda found that primate densities were similar in forest that had been logged at low intensity and forest logged at high intensity. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1485https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1485Tue, 17 Oct 2017 19:26:45 +0100Collected Evidence: Collected Evidence: Provide monetary benefits to local communities for sustainably managing their forest and its wildlife (e.g. REDD, employment) One before-and-after study in Belize found that numbers of black howler monkeys increased by 138% over 13 years after local communities received monetary benefits, alongside other interventions. One before-and-after study in the Republic of Congo found that most central chimpanzees reintroduced to an area where local communities received monetary benefits, alongside other interventions, survived over five years. One before-and-after study in Rwanda, Uganda and the Democratic Republic of Congo found that numbers of mountain gorillas declined by 28% over 41 years despite the implementation of development projects in nearby communities, alongside other interventions. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1509https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1509Wed, 18 Oct 2017 15:15:52 +0100Collected Evidence: Collected Evidence: Habituate primates to human presence to reduce stress from tourists/researchers etc. A before-and-after study in Brazil found that an introduced population of golden lion tamarins declined after one year, following habituation to human presence, alongside other interventions. A before-and-after study in Madagascar found that the majority of introduced black-and-white ruffed lemurs and diademed sifakas survived over 30 months, following habituation to human presence, alongside other interventions. A controlled, before-and-after study in Rwanda, Uganda, and Democratic Republic of Congo found that a mountain gorilla population increased over 41 years, following habituation to human presence, alongside other interventions. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1519https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1519Thu, 19 Oct 2017 09:30:50 +0100Collected Evidence: Collected Evidence: Provide additional sleeping platforms/nesting sites for primates One before-and-after study in Brazil found that a translocated lion tamarin population declined after artificial nest boxes were provided, alongside other interventions. One before-and-after study in Brazil found that a majority of reintroduced golden lion tamarins died seven years after artificial nest boxes were provided, alongside other interventions. One before-and-after study in Gabon found that a majority of juvenile western lowland gorillas survived for at least seven years after nesting platforms were provided, alongside other interventions. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1530https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1530Thu, 19 Oct 2017 10:22:21 +0100Collected Evidence: Collected Evidence: Keep safety distance to habituated animals One before-and-after study in the Democratic Republic of Congo found that most reintroduced chimpanzees survived over five years after being followed from a distance of 5–100 m, alongside other interventions. One controlled study in Malaysia found that the number of reintroduced orangutans declined by 33% over 31 years despite visitors being required to keep a safety distance to the animals, alongside other interventions. One before-and-after study in Rwanda, Uganda and Congo found that numbers of mountain gorillas increased by 168% over 41 years while being observed from a safety distance, alongside other interventions. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1538https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1538Thu, 19 Oct 2017 14:38:23 +0100Collected Evidence: Collected Evidence: Parrot’s feather: Use of herbicides - diquat Two laboratory studies (including a replicated, randomized, controlled study) in the USA found that diquat reduced the growth of parrot’s feather. One replicated, randomized, controlled field study in Portugal found that growth was not reduced after the application of diquat. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1680https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1680Mon, 23 Oct 2017 09:11:46 +0100Collected Evidence: Collected Evidence: Parrot’s feather: Use of herbicides - endohall Two replicated, controlled laboratory studies in New Zealand and the USA found that endothall reduced the growth of parrot’s feather. One replicated, randomized, controlled field study in New Zealand found that parrot’s feather plants treated with endohall presented lower cover soon after herbicide application but cover later increased to levels similar to pre-treatment. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1681https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1681Mon, 23 Oct 2017 09:16:19 +0100Collected Evidence: Collected Evidence: Use prescribed fire to maintain or restore disturbance Three studies evaluated the effects, on peatland vegetation, of using prescribed fire to maintain or restore disturbance. Two studies were in fens and one was in a bog. N.B. Prescribed burning in peatlands with no history of disturbance is considered as a separate action. Characteristic plants (1 study): One replicated before-and-after study in a fen in the UK reported that burning (along with other interventions) had no effect on cover of fen-characteristic mosses or herbs. Herb cover (2 studies): One replicated, controlled study in a fen in the USA reported that burning reduced forb cover and increased sedge/rush cover, but had no effect on grass cover. In contrast, one replicated before-and-after study in a fen in the UK reported that burning (along with other interventions) reduced grass/sedge/rush cover. Tree/shrub cover (2 studies): Two replicated studies in fens in the USA and the UK reported that burning (sometimes along with other interventions) reduced tree/shrub cover. Overall plant richness/diversity (3 studies): Two replicated, controlled studies in a fen in the USA and a bog in New Zealand found that burning increased plant species richness or diversity. However, one replicated before-and-after study in a fen in the UK reported that burning (along with other interventions) typically had no effect on plant species richness and diversity. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1763https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1763Mon, 27 Nov 2017 21:37:27 +0000Collected Evidence: Collected Evidence: Carnivores: Provide devices to simulate live prey, including sounds, lures, pulleys and bungees Two before-and-after studies in the USA and the UK found that activity levels and behavioural diversity increased in felids when presented with a lure or pulley system. One replicated, before-and-after study in the USA found that pacing behaviour decreased and walking increased in cougars, but pacing initially increased in tigers, when provided with a carcass on a bungee. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1927https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1927Wed, 24 Jan 2018 12:29:30 +0000
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.

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