William J. Sutherland

Consequences of the Allee effect for behaviour, ecology and conservation

Warder C. Allee brought attention to the possibility of a positive relationship between aspects of fitness and population size 50 years ago. Until recently, however, this concept was generally regarded as an intriguing but relatively unimportant aspect of population ecology. Increasing appreciation that Allee effects must be incorporated into models of population dynamics and habitat use, together with recent interest in the implications of sociality for conservation, have shown that for ecology and conservation the consequences of the Allee effect are profound. The Allee effect can be regarded not only as a suite of problems associated with rarity, but also as the basis of animal sociality.

What Is the Allee Effect

W. C. Allee brought attention to the possibility of a positive relationship between aspects of fitness and population size over fifty years ago. This phenomenon, frequently termed the Allee effect, has been the focus of increased interest over the past two decades in the light of concerns over conservation and the problems of rarity. Use of the term suffers from the absence of a clear definition however, with the result that Allee effects are frequently thought to involve only a narrow range of phenomena and are often overlooked altogether. We propose a definition for the effect and attempt to resolve the major issues underlying the confusion surrounding this term.

Ecological census techniques : a handbook

Preface 1. Planning a research programme William J. Sutherland 2. Principles of sampling Jeremy J. D. Greenwood and Robert A. Robinson 3. General census methods Jeremy J. D. Greenwood and Robert A. Robinson 4. Plants James M. Bullock 5. Invertebrates Malcolm Ausden and Martin Drake 6. Fish Isabelle M. Cote and Martin R. Perrow 7. Amphibians Tim R. Halliday 8. Reptiles Simon Blomberg and Richard Shine 9. Birds David W. Gibbons and Richard D. Gregory 10. Mammals Charles Krebs 11. Environmental variables Jacquelyn C. Jones, John D. Reynolds and Dave Raffaelli 12. The twenty commonest censusing sins William J. Sutherland Index.

Biodiversity Conservation: Challenges Beyond 2010

Biodiversity Convention In October 2010, the Convention on Biological Diversity will meet to assess the current condition of global biodiversity and to propose and agree on priorities for its future conservation. In this context, Rands et al. (p. 1298; see the News Focus section; see the cover) review recent patterns of biodiversity conservation, highlighting successes, as well as current and future threats. They argue that biodiversity should be treated as a public good, with responsibility for its conservation integrated across sectors of society and government, rather than be confined to the business of environmental agencies, and review the conditions under which this goal might be achieved. The continued growth of human populations and of per capita consumption have resulted in unsustainable exploitation of Earth’s biological diversity, exacerbated by climate change, ocean acidification, and other anthropogenic environmental impacts. We argue that effective conservation of biodiversity is essential for human survival and the maintenance of ecosystem processes. Despite some conservation successes (especially at local scales) and increasing public and government interest in living sustainably, biodiversity continues to decline. Moving beyond 2010, successful conservation approaches need to be reinforced and adequately financed. In addition, however, more radical changes are required that recognize biodiversity as a global public good, that integrate biodiversity conservation into policies and decision frameworks for resource production and consumption, and that focus on wider institutional and societal changes to enable more effective implementation of policy.

Why behavioural responses may not reflect the population consequences of human disturbance

The effect of human disturbance on animals is frequently measured in terms of changes in behaviour in response to human presence. The magnitude of these changes in behaviour is then often used as a measure of the relative susceptibility of species to disturbance; for example species which show strong avoidance of human presence are often considered to be in greater need of protection from disturbance than those which do not. In this paper we discuss whether such changes in behaviour are likely to be good measures of the relative susceptibility of species, and suggest that their use may result in confusion when determining conservation priorities.

Ideal free distributions when individuals differ in competitive ability: phenotype-limited ideal free models

Abstract A series of prospective models is developed to investigate ideal free distributions in populations where individuals differ in competitive ability. The models are of three types. In the continuous-input models, there is continuous arrival of food or mates into each habitat patch, and competitors scramble to obtain as large a share as possible. In the interference models, the prey density in a particular patch stays constant but the presence of competitors slows down the rate at which prey are captured. In the kleptoparasitism model, individuals have food or females stolen from them by competitors higher in the dominance hierarchy, and in turn steal items from subordinates. A general result of the continuous-input and interference models is that the population of competitors can be truncated between patches so that the individuals with the highest competitive ability occur in the best patches, or in the patches where competitive differences are greatest. Individuals of lowest competitive ability occur in the poorest patches or where competitive differences are least, and intermediate phenotypes are ranked between these two extremes. Thus the ideal free prediction that all individuals will achieve equal fitness will not apply. However, in continuous-input cases where competitive differences between phenotypes remain constant across patches, this solution is only neutrally stable, and forms only one element of a set of equilibrium distributions. The fact that many empirical studies of continuous-input have found approximately equal mean fitness across patches may relate to this finding. Most interference studies contradict the simple ideal free solution by having different mean intake rates across patches; this may relate to the predicted positive correlation of competitive ability with patch quality. The kleptoparasitism model usually generated continuous cycling of individuals between habitat patches, though some correlation could be found between competitive ability and patch quality.

A horizon scan of global conservation issues for 2014

Highlights • This is the fifth in our annual series of horizon scans published in TREE.• We identify 15 issues that we considered insufficiently known by the conservation community.• These cover a wide range of issues. Four relate to climate change, two to invasives and two to disease spread.• This exercise has been influential in the past.

One Hundred Questions of Importance to the Conservation of Global Biological Diversity

We identified 100 scientific questions that, if answered, would have the greatest impact on conservation practice and policy. Representatives from 21 international organizations, regional sections and working groups of the Society for Conservation Biology, and 12 academics, from all continents except Antarctica, compiled 2291 questions of relevance to conservation of biological diversity worldwide. The questions were gathered from 761 individuals through workshops, email requests, and discussions. Voting by email to short-list questions, followed by a 2-day workshop, was used to derive the final list of 100 questions. Most of the final questions were derived through a process of modification and combination as the workshop progressed. The questions are divided into 12 sections: ecosystem functions and services, climate change, technological change, protected areas, ecosystem management and restoration, terrestrial ecosystems, marine ecosystems, freshwater ecosystems, species management, organizational systems and processes, societal context and change, and impacts of conservation interventions. We anticipate that these questions will help identify new directions for researchers and assist funders in directing funds.

The Influence of Late Quaternary Climate-Change Velocity on Species Endemism

Regions with low glacial-interglacial climate-change velocity were essential refuges for many small-ranged species. The effects of climate change on biodiversity should depend in part on climate displacement rate (climate-change velocity) and its interaction with species’ capacity to migrate. We estimated Late Quaternary glacial-interglacial climate-change velocity by integrating macroclimatic shifts since the Last Glacial Maximum with topoclimatic gradients. Globally, areas with high velocities were associated with marked absences of small-ranged amphibians, mammals, and birds. The association between endemism and velocity was weakest in the highly vagile birds and strongest in the weakly dispersing amphibians, linking dispersal ability to extinction risk due to climate change. High velocity was also associated with low endemism at regional scales, especially in wet and aseasonal regions. Overall, we show that low-velocity areas are essential refuges for Earth’s many small-ranged species.

Understanding and managing conservation conflicts.

Conservation conflicts are increasing and need to be managed to minimise negative impacts on biodiversity, human livelihoods, and human well-being. Here, we explore strategies and case studies that highlight the long-term, dynamic nature of conflicts and the challenges to their management. Conflict management requires parties to recognise problems as shared ones, and engage with clear goals, a transparent evidence base, and an awareness of trade-offs. We hypothesise that conservation outcomes will be less durable when conservationists assert their interests to the detriment of others. Effective conflict management and long-term conservation benefit will be enhanced by better integration of the underpinning social context with the material impacts and evaluation of the efficacy of alternative conflict management approaches.