Hero mobile image

Conservation Evidence Journal

Publishing evidence to improve practice


The Conservation Evidence Journal shares the global experience of those on the front line of conservation practice about the effectiveness of conservation actions. All papers include monitoring of the effects of the intervention and are written by, or in partnership with, those who did the conservation work. We encourage articles from anywhere around the world on all aspects of species and habitat management such as habitat creation, habitat restoration, translocations, reintroductions, invasive species control, changing attitudes and education. 

The Conservation Evidence Journal publishes peer-reviewed papers throughout the year collected in an annual Volume. We publish Special Issues and collate Collections on specific topics, such as management of particular groups of species or habitats. To search for papers on a specific topic within the journal select Advanced search, enter your keyword(s) and within the Source box type: "conservation evidence". This will take you to a list of actions that contain Conservation Evidence Journal papers. In order to see the list of individual Conservation Evidence Journal papers on the topic, please click on 'You can also search Individual Studies' at the top of this page.

Creative Commons License Copyright is retained by the author(s). All papers published in the Conservation Evidence Journal are open access and licensed under a Creative Commons Attribution 4.0 International License

The Conservation Evidence Journal is a separate publication within the Conservation Evidence project. Conservation Evidence is a free, authoritative information resource designed to support decisions about how to maintain and restore global biodiversity. You can search for summarised evidence from the scientific literature about the effects of actions for species groups and habitats using our online database

Submit to Conservation Evidence Journal

Volume 19

EDITORIAL Creating testable questions in practical conservation: a process and 100 questions

Sutherland W.J., Robinson J.M., Aldridge D.C., Alamenciak T., Armes M., Baranduin N., Bladon A.J., Breed M.F., Dyas N., Elphick C.S., Griffiths R.A., Hughes J., Middleton B., Littlewood N.A., Mitchell R., Morgan W.H., Mosley R., Petrovan S.O., Prendergast K., Ritchie E.G., Raven H., Smith R.K., Watts S.H. & Thornton A. (2022), 19, 1-7


It is now clear that the routine embedding of experiments into conservation practice is essential for creating reasonably comprehensive evidence of the effectiveness of actions. However, an important barrier is the stage of identifying testable questions that are both useful but also realistic to carry out without a major research project. We identified approaches for generating such suitable questions. A team of 24 participants crowdsourced suggestions, resulting in a list of a hundred possible tests of actions.


Effectiveness of actions intended to achieve a voluntary transition from the use of lead to non-lead shotgun ammunition for hunting in Britain

Green R.E., Taggart M.A., Pain D.J., Clark N.A., Clewley L., Cromie R., Dodd S.G., Elliot B., Green R.M.W., Huntley B., Huntley J., Pap S., Porter R., Robinson J.A., Sheldon R., Smith K.W., Smith L., Spencer J. & Stroud D. (2022), 19, 8-14


In 2020, nine major UK shooting and rural organisations proposed a voluntary transition from the use for hunting of lead shotgun ammunition to non-lead alternatives. The major food retailer Waitrose & Partners has announced its intention to move to not supplying game meat products from animals killed using any kind of lead ammunition and the National Game Dealers Association announced a plan for a similar policy to be implemented in 2022. The SHOT-SWITCH research project, which is intended to monitor the progress of these voluntary initiatives, began in the 2020/2021 shooting season. The project monitors changes in the proportions of wild-shot common pheasants Phasianus colchicus available to consumers in Great Britain that had been killed using lead and non-lead shotgun ammunition, as assessed by using inductively coupled plasma atomic emission spectrometry to identify the composition of shotgun pellets recovered from carcasses. In 2020/2021, 99.4% of the pheasants sampled had been killed using lead ammunition. We report here further results from this study for the 2021/2022 season. We found that 99.5% of the 215 pheasants from which shotgun pellets were recovered had been killed using lead ammunition. We conclude that the shooting and rural organisations’ joint statement and two years of their considerable efforts in education, awareness-raising and promotion, have not yet had a detectable effect on the ammunition types used by hunters who supply pheasants to the British game meat market.


Artificial nesting platforms support population recovery of the Dalmatian pelican Pelecanus crispus along the Danube River in Bulgaria

Cheshmedzhiev S., Todorov E., Koev V., Mihov S. & Kutzarov Y. (2022), 19, 15-20


The Dalmatian pelican Pelecanus crispus is a Near Threatened species of waterbird with populations in the wetlands of the Lower Danube River. Breeding populations declined due to habitat loss and wetland drainage and conservation efforts have focused on bringing breeding Dalmatian pelicans back to their former wetland sites in Bulgaria. Since 2008, conservation efforts have focused on building artificial nesting platforms at marshes along the Lower Danube River. These efforts resulted in considerable growth of the population in the country. Between 2011 and 2021, four wooden platforms were installed at the Belene Island wetland complex (Pechina and Martvo Marshes) and the Kalimok wetland complex. All four platforms were used successfully by pelicans, resulting in the formation of two new breeding colonies and a total of 91 pairs in 2021. The majority, 88 pairs, were recorded at the Belene Island marshes, with the remainder at the Kalimok colony. The average annual breeding success was 1.17 young per pair at Peschina Marsh (occupied from 2016-2021), 0.90 at Martvo Marsh (2020-2021), and 1.33 at Kalimok (2021). The average across all three colonies was 1.14 young per pair. By 2021, the breeding population of Dalmatian pelicans in Bulgaria had grown to 131-150 breeding pairs at three locations.


Effect of roost management on populations trends of Rhinolophus hipposideros and Rhinolophus ferrumequinum in Britain and Ireland

Wright P.G.R., Kitching T., Hanniffy R., Bollo Palacios M., McAney K. & Schofield H. (2022), 19, 21-26


After a significant population decline during the 20th century, populations of both greater and lesser horseshoe bats have increased over recent decades in Britain and populations of lesser horseshoe bats have increased in Ireland. Vincent Wildlife Trust (VWT) acquired 37 bat reserves since the 1980s with the aim to safeguard the sites and enhance the roosting and hibernation conditions in buildings that were often derelict and sub-optimal for bats. These measures have resulted in a strong population size increase of all colonies. However, populations have also been increasing throughout Britain and Ireland as a consequence of legal protection and milder winters resulting in higher survival rates. Therefore, it is not clear whether the measures that have taken place in VWT reserves have led to a greater increase than roosts that have not benefited from the same type of management. We aimed to compare population trends of horseshoe bat roosts under VWT management and non-VWT management from 1999 to 2020 in order to assess its effectiveness. For this, we analysed population trends at sites under different management types (VWT and non-VWT) for lesser horseshoe bats in Britain and Ireland and greater horseshoe bats in Britain. Our results indicated that populations in Britain under VWT management have increased by 366% (CI 225% - 580%) for greater horseshoe bats and 188% (CI 125% - 283%) for lesser horseshoe bats. Roosts that did not benefit from the same levels of management increased respectively by 164% (CI 132% - 199%) and 51% (CI 40% - 60%). In Ireland, populations of lesser horseshoe bats in VWT managed roosts increased by 217% (CI 118% - 364%) while non-VWT managed roosts remained stable (-0.44%; CI -23% - 29%). We conclude that management actions carried out by VWT of greater and lesser horseshoe bat roosts have helped populations recover at a faster rate by securing the integrity of buildings, improving access points and by providing optimal microclimatic conditions within the buildings.


A small, heated roost facilitates nursery establishment and increases the size of a lesser horseshoe bat (Rhinolophus hipposideros) colony in the northern Swiss Alps

Zingg P.E., von Weissenfluh U. & Schaub M. (2022), 19, 27-34


Small thermal roofs in building attics might be a promising option to maintain and support nursery colonies of bats, but little empirical evidence is available. In a controlled study conducted from 2014 to 2021 on the northern side of the Swiss Alps, we investigated the effects of a thermal roof within an attic on the establishment and size of a nursery of lesser horseshoe bats Rhinolophus hipposideros. We installed a gable roof as a thermal roof (1.4 m2 of usable roosting area with two internal heating mats) in the attic of a building that previously did not host a bat colony, monitored the temperature and later counted the number of roosting bats. The building is near a power station that hosted lesser horseshoe bats but which was shut down and becoming too cool to support a nursery colony of this species. The ridge of the thermal roof had a temperature of about 33°C, while the temperature in the building's sub-roof was lower on average and subject to greater temporal fluctuations. Two years after installation, the bats started to use the roost consistently in summer and the numbers grew from 22 in 2014 to 239 in 2021. During 136 survey days we found that 85% of the bats were roosting in the small thermal roof, and only a minority were in the much larger sub-roof suggesting that the former was preferred. Our study provides empirical evidence that a thermal roof can initiate the colonisation of a replacement roost and support colony growth.


Does provision of supplementary food to grey partridges Perdix perdix help their over-winter survival on upland hill farms in northern England?

Warren P., Hornby T. & Baines D. (2022), 19, 35-40


Grey partridge populations in the UK have declined dramatically since 1970. These birds are mainly associated with lowland cereal farms, but they are also found on marginal hill farms in northern England where they frequent rough grasslands created by low-intensity sheep farming. Here, important populations remain, but the availability of winter food, particularly in years with prolonged snow appears a major limiting factor. To investigate whether food shortages in winter limit grey partridge survival, we experimentally tested whether we could improve their survival by increasing the provision of supplementary food within five study plots, each paired with a control, over two consecutive winters. Grey partridges found and used feeding stations, with discovery time on average 12 days earlier in the second winter. The frequency of hopper use also increased on four of the five fed plots in the second winter. We found no differences in an index of over-winter survival nor subsequent breeding success in relation to the feeding treatment. However, the study coincided with two mild winters with little snow and the provision of supplementary food may be more important in more severe winters with prolonged snow cover. Grey partridges readily used feed hoppers and we recommend their provision to provide emergency food sources in severe winter weather whilst longer-term land-use based solutions are sought.


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

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