Closing yield gaps: perils and possibilities for biodiversity conservation.

Increasing agricultural productivity to 'close yield gaps' creates both perils and possibilities for biodiversity conservation. Yield increases often have negative impacts on species within farmland, but at the same time could potentially make it more feasible to minimize further cropland expansion into natural habitats. We combine global data on yield gaps, projected future production of maize, rice and wheat, the distributions of birds and their estimated sensitivity to changes in crop yields to map where it might be most beneficial for bird conservation to close yield gaps as part of a land-sparing strategy, and where doing so might be most damaging. Closing yield gaps to attainable levels to meet projected demand in 2050 could potentially help spare an area equivalent to that of the Indian subcontinent. Increasing yields this much on existing farmland would inevitably reduce its biodiversity, and therefore we advocate efforts both to constrain further increases in global food demand, and to identify the least harmful ways of increasing yields. The land-sparing potential of closing yield gaps will not be realized without specific mechanisms to link yield increases to habitat protection (and restoration), and therefore we suggest that conservationists, farmers, crop scientists and policy-makers collaborate to explore promising mechanisms.BP was funded by the Zukerman Research Fellowship in Global Food Security at King’s College, Cambridge.This is the accepted manuscript of a paper which was published in the Philosophical Transactions of the Royal Society B: Biological Sciences (B Phalan, R Green, A Balmford, Phil. Trans. R. Soc. B 2014, 369, 20120285

Taxonomic status of the Liberian Greenbul Phyllastrephus leucolepis and the conservation importance of the Cavalla Forest, Liberia

We thank Jochen Martens for his long-lasting patience in dealing with the specimen of leucolepis, and Brian Hillcoat for comments and advice. It is hardly possible to thank by name all those who have supported WG over the past 30 years and more since 1981 in the fields of forest ecology and ornithology in eastern Liberia. In particular, we express gratitude to Alex Peal and Theo Freeman, both Heads of Wildlife and National Parks, for their many years of cooperation, and the Silviculture Officers Wynn Bryant, Momo Kromah and Steve Miapeh. The knowledge of the tree experts Joe Keper and Daniel Dorbor helped us to gain insights into the ecological complexities of the relationship between man, birds and trees. William Toe worked for three years as bird trapper and assistant in bird banding. WG’s attachment to the University of Liberia and to the students who so often accompanied him was made possible by Ben Karmorh from the Environmental Protection Agency (EPA) and University of Liberia. NABU, the German Conservation Society, has supported the Liberian projects for almost 30 years now. We also thank Nigel Collar, Françoise Dowsett-Lemaire and Hannah Rowland for comments and advice. We thank the African Bird Club and the Royal Society for the Protection of Birds for helping to fund the 2013 expedition to the Cavalla Forest, in particular Alice Ward-Francis, Robert Sheldon, Alan Williams and Keith Betton. We also are extremely grateful to Michael Garbo and staff of the Society for the Conservation of Nature in Liberia for all manner of help with the expedition, to Harrison Karnwea and colleagues at the Forest Development Authority of Liberia for permissions and other support, as well as to Emmanuel Loqueh, Trokon Grimes, Flomo Molubah and Amos ‘Dweh’ Dorbor for being such excellent companions in the field. YL performed the genetic work as part of her M.Sc. (Genetics) at the University of Aberdeen, whose support is acknowledged.Peer reviewedPublisher PD

Translating cognitive insights into effective conservation programs: reply to Schakner et al.

This is the author accepted manuscript. The final version is available from Elsevier via http://dx.doi.org/10.1016/j.tree.2014.09.00

Comparative cognition for conservationists.

Every animal occupies a unique cognitive world based on its sensory capacities, and attentional and learning biases. Behaviour results from the interaction of this cognitive world with the environment. As humans alter environments, cognitive processes ranging from perceptual processes to learned behaviour govern animals' reactions. By harnessing animals' perceptual biases and applying insights from cognitive theory, we can purposefully alter cues to reduce maladaptive responses and shape behaviour. Despite the fundamental connection between cognition and behaviour, the breadth of cognitive theory is underutilised in conservation practice. Bridging these disciplines could augment existing conservation efforts targeting animal behaviour. We outline relevant principles of perception and learning, and develop a step-by-step process for applying aspects of cognition towards specific conservation issues.We would like to thank Nick Davies and several anonymous reviewers for helpful discussions and comments on the manuscript, and Edward Legg and Ljerka Ostojic for feedback on the figures. A.L.G. received generous support from the Gates-Cambridge Trust; A.T. is funded by a BBSRC David Phillips Fellowship (BB/H021817/1); B.P. is funded by a Zukerman Research Fellowship at King's College.This is the final version of the article. It first appeared from Elsevier via http://dx.doi.org/10.1016/j.tree.2014.06.00

Reducing the land use of EU pork production: where there's swill, there's a way.

Livestock production occupies approximately 75% of agricultural land, consumes 35% of the world's grain, and produces 14.5% of anthropogenic greenhouse gas emissions. With demand for meat and dairy products forecast to increase 60% by 2050, there is a pressing need to reduce the footprint of livestock farming. Food wastes have a long history as a source of environmentally benign animal feed, but their inclusion in feed is currently banned in the EU because of disease control concerns. A number of East Asian states have in the last 20 years, however, introduced regulated, centralised systems for safely recycling food wastes into animal feed. This study quantifies the land use savings that could be realised by changing EU legislation to promote the use of food wastes as animal feed and reviews the policy, public, and industry barriers to the use of food waste as feed. Our results suggest that the application of existing technologies could reduce the land use of EU pork (20% of world production) by one fifth, potentially saving 1.8 million hectares of agricultural land. While swill presents a low-cost, low-impact animal feed, widespread adoption would require efforts to address consumer and farmer concerns over food safety and disease control.E.K.H.J.zE is funded by BBSRC grant BB/J014540/1.This is the final version of the article. It was first available from Elsevier via http://dx.doi.org/10.1016/j.foodpol.2015.11.00

Crop expansion and conservation priorities in tropical countries

Expansion of cropland in tropical countries is one of the principal causes of biodiversity loss, and threatens to undermine progress towards meeting the Aichi Biodiversity Targets. To understand this threat better, we analysed data on crop distribution and expansion in 128 tropical countries, assessed changes in area of the main crops and mapped overlaps between conservation priorities and cultivation potential. Rice was the single crop grown over the largest area, especially in tropical forest biomes. Cropland in tropical countries expanded by c. 48,000 km2 per year from 1999–2008. The countries which added the greatest area of new cropland were Nigeria, Indonesia, Ethiopia, Sudan and Brazil. Soybeans and maize are the crops which expanded most in absolute area. Other crops with large increases included rice, sorghum, oil palm, beans, sugar cane, cow peas, wheat and cassava. Areas of high cultivation potential—while bearing in mind that political and socio-economic conditions can be as influential as biophysical ones—may be vulnerable to conversion in the future. These include some priority areas for biodiversity conservation in tropical countries (e.g., Frontier Forests and High Biodiversity Wilderness Areas), which have previously been identified as having ‘low vulnerability’, in particular in central Africa and northern Australia. There are also many other smaller areas which are important for biodiversity and which have high cultivation potential (e.g., in the fringes of the Amazon basin, in the Paraguayan Chaco, and in the savanna woodlands of the Sahel and East Africa). We highlight the urgent need for more effective sustainability standards and policies addressing both production and consumption of tropical commodities, including robust land-use planning in agricultural frontiers, establishment of new protected areas or REDD+ projects in places agriculture has not yet reached, and reduction or elimination of incentives for land-demanding bioenergy feedstock

How imperfect can land sparing be before land sharing is more favourable for wild species?

Two solutions, at opposite ends of a continuum, have been proposed to limit negative impacts of human agricultural demand on biodiversity. Under land sharing, farmed landscapes are made as beneficial to wild species as possible, usually at the cost of lower yields. Under land sparing, yields are maximised and land not needed for farming is spared for nature. Multiple empirical studies have concluded that land-sparing strategies would be the least detrimental to wild species, provided the land not needed for agriculture is actually spared for nature. However, the possibility of imperfections in the delivery of land sparing has not been comprehensively considered. Land sparing can be imperfect in two main ways: land not required for food production may not be used for conservation (incomplete area sparing), and habitat spared may be of lower quality than that assessed in surveys (lower habitat quality sparing). Here we use published data relating population density to landscape-level yield for birds and trees in Ghana (167 and 220 species respectively) and India (174 birds, 40 trees) to assess effects of imperfect land sparing on region-wide population sizes and hence population viabilities. We find that incomplete area and lower habitat quality imperfections both reduce the benefits of a land-sparing strategy. However, sparing still outperforms sharing whenever >= 28% of land that could be spared is devoted to conservation, or the quality of land spared is >= 29% of the value of that surveyed. Thresholds are even lower under alternative assumptions of how population viability relates to population size and for species with small global ranges, and remain low even when both imperfections co-occur. Comparison of these thresholds with empirical data on the likely real-world performance of land sparing suggests that reducing imperfections in its delivery would be highly beneficial. Nevertheless, given plausible relationships between population size and population viability, land sparing outperforms land sharing despite its imperfections. Policy implications. Our results confirm that real-world difficulties in implementing land sparing will have significant impacts on biodiversity. They also underscore the need for strategies which explicitly link yield increases to setting land aside for conservation, and for adoption of best practices when spared land requires restoration. However, land-sparing approaches to meeting human agricultural demand remain the least detrimental to biodiversity, even with current imperfections in implementation

Conserving the birds of Uganda's Banana-Coffee Arc: Land Sparing and Land Sharing Compared

Reconciling the aims of feeding an ever more demanding human population and conserving biodiversity is a difficult challenge. Here, we explore potential solutions by assessing whether land sparing (farming for high yield, potentially enabling the protection of non-farmland habitat), land sharing (lower yielding farming with more biodiversity within farmland) or a mixed strategy would result in better bird conservation outcomes for a specified level of agricultural production. We surveyed forest and farmland study areas in southern Uganda, measuring the population density of 256 bird species and agricultural yield: food energy and gross income. Parametric non-linear functions relating density to yield were fitted. Species were identified as "winners" (total population size always at least as great with agriculture present as without it) or "losers" (total population sometimes or always reduced with agriculture present) for a range of targets for total agricultural production. For each target we determined whether each species would be predicted to have a higher total population with land sparing, land sharing or with any intermediate level of sparing at an intermediate yield. We found that most species were expected to have their highest total populations with land sparing, particularly loser species and species with small global range sizes. Hence, more species would benefit from high-yield farming if used as part of a strategy to reduce forest loss than from low-yield farming and land sharing, as has been found in Ghana and India in a previous study. We caution against advocacy for high-yield farming alone as a means to deliver land sparing if it is done without strong protection for natural habitats, other ecosystem services and social welfare. Instead, we suggest that conservationists explore how conservation and agricultural policies can be better integrated to deliver land sparing by, for example, combining land-use planning and agronomic support for small farmers

Avoiding impacts on biodiversity through strengthening the first stage of the mitigation hierarchy

The mitigation hierarchy is a decision-making framework designed to address impacts on biodiversity and ecosystem services through first seeking to avoid impacts wherever possible, then minimizing or restoring impacts, and finally by offsetting any unavoidable impacts. Avoiding impacts is seen by many as the most certain and effective way of managing harm to biodiversity, and its position as the first stage of the mitigation hierarchy indicates that it should be prioritized ahead of other stages. However, despite an abundance of legislative and voluntary requirements, there is often a failure to avoid impacts. We discuss reasons for this failure and outline some possible solutions. We highlight the key roles that can be played by conservation organizations in cultivating political will, holding decision makers accountable to the law, improving the processes of impact assessment and avoidance, building capacity, and providing technical knowledge. A renewed focus on impact avoidance as the foundation of the mitigation hierarchy could help to limit the impacts on biodiversity of large-scale developments in energy, infrastructure, agriculture and other sectors