Barbara Clucas

Flagship species on covers of US conservation and nature magazines

Some conservation organizations publish magazines that showcase current conservation and research projects, attract new subscribers and maintain membership, often using flagship species to promote these objectives. This study investigates the nature of flagship species featured on the covers of ten representative US conservation and nature magazines, Defenders, National Wildlife, Wildlife Conservation, Zoonooz, Nature Conservancy, Outdoor America, Sierra, Audubon, California Wild and Natural History. Operationally defining flagship species by diet, taxonomic order, body size and IUCN status, we found that magazines tend to use mammal and bird species rather than invertebrate, fish, amphibian, reptile or plant taxa on their covers. Featured birds were mostly omnivorous or piscivorous, large-bodied and of little conservation concern; featured mammals were mainly carnivorous or herbivorous, large-bodied and of considerable conservation concern. These analyses confirm, for the first time, anecdotal observations about conservation organizations focusing their publicity and programmes on large, charismatic species to raise awareness and funds and raise the spectre that the public may be exposed to only a selected sample of conservation problems.

Patterns of Behavior: Konrad Lorenz, Niko Tinbergen, and the Founding of Ethology

R. W. Burkhardt Jr. 2005. Patterns of Behavior: Konrad Lorenz, Niko Tinbergen, and the Founding of Ethology. University of Chicago Press, Chicago, Illinois, 496 pp. ISBN 0-226-08090-0, price (paper),

Lizards speed up visual displays in noisy motion habitats

29.00. Burkhardt, a historian of biology, 1st began his research for Patterns of Behavior five years after Konrad Lorenz, Niko Tinbergen, and Karl von Frisch shared the 1973 Nobel Prize in Physiology or Medicine for their contributions to the founding of ethology. Ethology, Burkhardt quotes Tinbergen, is “the biological study of behavior.” Patterns of Behavior begins in the early 1900s, connecting major as well as minor events that led to the founding of ethology as a scientific field in the 1930s and through its development into the 1970s. The high level of detail in this book is a testament to Burkhardts patience and persistence in pulling together a mass of sources, including records of conversations, letters, presentations, publications, photographs, and personal interviews. Patterns of Behavior is a close examination of how people, place, and society (e.g., politics) interact to influence scientific theories and structure research directions. Burkhardt provides minibiographies of scientists who directly or indirectly influenced ethology. The first 2 chapters cover the forerunners of ethology, including scientists from the United States (Charles Otis and Whitman Wallace Craig) and …

How much is that birdie in my backyard? A cross-continental economic valuation of native urban songbirds

Extensive research over the last few decades has revealed that many acoustically communicating animals compensate for the masking effect of background noise by changing the structure of their signals. Familiar examples include birds using acoustic properties that enhance the transmission of vocalizations in noisy habitats. Here, we show that the effects of background noise on communication signals are not limited to the acoustic modality, and that visual noise from windblown vegetation has an equally important influence on the production of dynamic visual displays. We found that two species of Puerto Rican lizard, Anolis cristatellus and A. gundlachi, increase the speed of body movements used in territorial signalling to apparently improve communication in visually ‘noisy’ environments of rapidly moving vegetation. This is the first evidence that animals change how they produce dynamic visual signals when communicating in noisy motion habitats. Taken together with previous work on acoustic communication, our results show that animals with very different sensory ecologies can face similar environmental constraints and adopt remarkably similar strategies to overcome these constraints.

New Directions in Urban Avian Ecology: Reciprocal Connections between Birds and Humans in Cities

Human-wildlife interactions in urban areas, both positive and negative, often involve people and birds. We assess the economic value placed on interactions with common native songbirds in two different urban areas (Berlin, Germany and Seattle, Washington, USA) by combining a revealed preference (recalled expenditures on bird feed) and a stated preference approach (determining willingness to pay for conservation or reduction of birds). Residents in both cities purchase bird food, engage in a range of bird-supporting activities and are generally willing to pay a small amount for native songbird conservation. Demographic, cultural and socio-economic factors, as well as specific attitudes towards birds and general attitudes about conservation were found to influence these decisions. This study presents the first attempt at estimating the economic value of enjoying common native urban songbirds and estimates the lower bound to be about 120 million USD/year in Seattle and 70 million USD/year in Berlin.

Donning your enemy's cloak: ground squirrels exploit rattlesnake scent to reduce predation risk

Ask any urban person what type of animal they see on a daily basis and the response will likely be “birds”. Whether it is their increased mobility due to flight compared to other animals, or a particular ability to adapt to changes in the environment, certain species of birds live in relatively high densities in human-dominated landscapes. Indeed, some species apparently thrive in urban habitats. The connection between birds and human settlements is not a recent one. For example, the house sparrow (Passer domesticus) is estimated to have begun its commensal relationship with humans between 400,000 and 10,000 years ago in the Middle East (Anderson 2006). Despite this ancient connection between people and birds the reciprocal nature of our interactions is just beginning to be investigated (e.g. Marzluff and Angell 2005).

A cross-continental look at the patterns of avian species diversity and composition across an urbanisation gradient

Ground squirrels (Spermophilus spp.) have evolved a battery of defences against the rattlesnakes (Crotalus spp.) that have preyed on them for millions of years. The distinctive behavioural reactions by these squirrels to rattlesnakes have recently been shown to include self-application of rattlesnake scent—squirrels apply scent by vigorously licking their fur after chewing on shed rattlesnake skins. Here, we present evidence that this behaviour is a novel antipredator defence founded on exploitation of a foreign scent. We tested three functional hypotheses for snake scent application—antipredator, conspecific deterrence and ectoparasite defence—by examining reactions to rattlesnake scent by rattlesnakes, ground squirrels and ectoparasites (fleas). Rattlesnakes were more attracted to ground squirrel scent than to ground squirrel scent mixed with rattlesnake scent or rattlesnake scent alone. However, ground squirrel behaviour and flea host choice were not affected by rattlesnake scent. Thus, ground squirrels can reduce the risk of rattlesnake predation by applying rattlesnake scent to their bodies, potentially as a form of olfactory camouflage. Opportunistic exploitation of heterospecific scents may be widespread; many species self-apply foreign odours, but few such cases have been demonstrated to serve in antipredator defence.

Fossils and phylogeny uncover the evolutionary history of a unique antipredator behaviour

Abstract Context. As humans become increasingly urban, the need for conservation of nature in cities increases and requires an understanding of the patterns and processes of urban ecosystems. In particular, because humans are the most dominant species in urban areas, understanding the role humans play in these ecosystems (direct and indirect) will be of primary importance. Aims. We examine the diversity and composition of bird species across an urbanisation gradient in two cities (Berlin, Germany, and Seattle, Washington, USA). We determine the degrees of species urban tolerance and examine how certain biological traits of species, namely, diet, whether or not species use bird feeders, nest sites and innovation rate, characterise species urban tolerance. Finally, we determine whether human provisioning (bird feeders and nest boxes) influences what types of species persist across the urbanisation gradient. Methods. We surveyed bird abundance and species richness using point counts and surveyed human provisioning by conducting door-to-door interviews of residents across an urbanisation gradient in Berlin and Seattle. Key results. We found that patterns of species richness were similar in both cities, but that species composition in Berlin changed less across the urbanisation gradient than it did in Seattle. The majority of birds in Berlin were urban tolerant, whereas in Seattle, they were moderately urban tolerant and intolerant. A cluster analysis revealed that, in general, in Berlin, omnivorous, open-nesting birds that use bird feeders and have relatively high innovation rates tended to be urban tolerant. In Seattle, birds that were mostly omnivorous, nested in open cups, and used bird feeders tended to be moderately urban tolerant and they were influenced by provisioning of food by humans. Conclusion. Urbanisation and human interactions with birds can act as ecological filters, favouring certain bird species that can lead to varying species compositions across an urban gradient. These differences in species composition across the gradient may be more noticeable in younger cities than in older cities where the filtering process has been occurring for longer time. Implications. By providing a variety of habitats and supplementing natural foods and nesting places, urban planners and residents can help conserve bird diversity in urban areas.

A systematic review of the relationship between urban agriculture and biodiversity

Recently, two squirrel species (Spermophilus spp.) were discovered to anoint their bodies with rattlesnake scent as a means of concealing their odour from these chemosensory predators. In this study, we tested multiple species with predator scents (rattlesnake and weasel) to determine the prevalence of scent application across the squirrel phylogeny. We reconstructed the evolutionary history of the behaviour using a phylogenetic analysis and fossil records of historic predator co‐occurrence. Squirrels with historical and current rattlesnake co‐occurrence all applied rattlesnake scent, whereas no relationship existed between weasel scent application and either weasel or rattlesnake co‐occurrence. This was surprising because experimental tests confirmed rattlesnake and weasel scent were both effective at masking prey odour from hunting rattlesnakes (the primary predator of squirrels). Ancestral reconstructions and fossil data suggest predator scent application in squirrels is ancient in origin, arising before co‐occurrences with rattlesnakes or weasels in response to some other, now extinct, chemosensory predator.

Top Predators as Conservation Tools: Ecological Rationale, Assumptions, and Efficacy

Urban agriculture is a unique form of agriculture that can provide fresh, local produce for urban residents, and may benefit biodiversity by decreasing the need to expand agriculture into natural areas as well as enhancing biodiversity in urban areas. However, although urban agriculture is also often cited as promoting biodiversity in urban areas, the extent of empirical evidence for such claims has not been studied. Here we systematically review the relationship between urban agriculture and biodiversity in the scientific literature. We strictly define urban agriculture as areas in cities that grow produce specifically for human consumption. We examined 148 papers from 2000 to 2017, of which only 24 studies fit our definition of urban agriculture, and of those, only 18 both involved urban agriculture and measured biodiversity. Of the studies that did measure biodiversity, some showed increases in diversity compared to urban vacant lots, but other showed no difference. Moreover, these studies were mostly focused on plants and invertebrates and were conducted almost exclusively in North America. In order to use the generalization that urban agriculture will have a positive influence on urban biodiversity, more studies will need to be conducted across a wider geographic range worldwide (particularly in developing countries in the tropics) and on a greater diversity of species and taxa (e.g., herpetiles, birds and small mammals). Such studies will likely increase in conservation importance as urban expansion and agricultural demands increase globally.