Human-modified Environments Research Articles

Western Purple-faced Langurs (Semnopithecus vetulus nestor) Feed on Ripe and Ripening Fruits in Human-modified Environments in Sri Lanka

Although most colobines feed mainly on leaves and a few feed heavily on seeds, colobine digestive adaptations for folivory are thought to preclude the high use of ripe fleshy fruits. In this long-term study of Semnopithecus vetulus nestor, the endemic western purple-faced langur of Sri Lanka, I investigated the feeding ecology and dietary flexibility for fruit feeding in 2 free-ranging groups (PT1 and R1) living in human-modified environments with abundant cultivated fruit, at Panadura and Piliyandala, for 19 mo and 13 mo respectively, using scan-sampling, vegetation enumeration, and phenological studies. In contrast to folivorous forest-living colobines, including other subspecies of Semnopithecus vetulus, my focal groups used more fruit (>50%) than foliage (PT1: 36%; R1: 34%). Both groups used many plant species (PT1 115; R1 59), but selected their food species, fruits over leaves, and young leaves over mature leaves. Fruit use was independent of young leaf availability. Notably, 78.4% and 83.4% of fruits consumed by PT1 and R1 were fleshy and human-edible, most of which were ripening or ripe (PT1: 72.4%; R1: 94.8%). The main fruit for both groups was Artocarpus heterophyllus (Moraceae; jakfruit), a cultivar with fleshy fruit. These findings differ from previous understanding of colobine diets. I suggest that environmental factors, such as the abundance and nature of available fruits, and the absence of arboreal-primate fruit competitors, could influence the use of ripe fleshy fruits by colobines strongly, highlighting the need to review the dietary and digestive flexibility of this group in changed and changing natural environments to formulate effective conservation action.

Exotic species, Experienced, and Idealized Nature

This paper is an answer to the Caplat and Coutts forum about our previous paper "The need for flexibility in conservation practices: exotic species as an example". We precise here why we proposed to consider exotic species as well as indigenous species in the reconnection framework in human-modified environments. One argument is that consistent and understandable arguments must be used in the communication from scientists to the public, in order not to decrease the gap between science and society.

A Low-Cost Manipulation of Food Resources Reduces Spatial Overlap Between Baboons (Papio ursinus) and Humans in Conflict

Competition over food and space is a primary driver of human–wildlife conflict. In the Cape Peninsula, South Africa, chacma baboons (Papio ursinus) have adapted to a human-modified environment, sleeping on the urban edge and raiding anthropogenic food sources on a daily basis. Human monitors, who herd baboons away from residential areas, are currently the preferred method of conflict mitigation. However, this method is costly and suffers from short-term interruptions, wherein the unexpected absence of monitors may lead to unprepared residents using lethal force to deter raiding baboons. Elsewhere in the chacma baboon distribution (in nonconflict areas), artificial food patches have been shown to alter troop movements drastically by eliciting consistent leadership behavior from alpha males. We investigated whether an artificial patch could be used to draw baboons away from the urban environment in the absence of monitors. First, we introduced an artificial food patch into natural land within a troop’s range and monitored movement and activity patterns. Although the troop utilized the patch, there was not a significant decline in use of the urban space as they continued to favor food in urban waste sites. Maintaining the patch, we then restricted access to these waste sites using wire-mesh fencing and observed a significant reduction in the time the troop spent within the urban space. In both experimental phases we observed consistent leadership, with dominant individuals arriving first at the patch and monopolizing food items thereon. Thus, we recommend the combined strategy of reducing raiding incentives in conjunction with provisioning as a short-term, cost-effective strategy to alter a baboon troop’s movement patterns and raiding frequency.

Merging wildlife community ecology with animal behavioral ecology for a better urban landscape planning

Cities are extremely human-modified environments, with few existing original habitats. Local, regional and global studies have indicated scale-dependent patterns of communities in relation to urbanization. In general, species with high abundance in urban environments are generalist species, whereas specialists have declined. However, these results do not indicate directly if urban habitats are either sink or source habitats for wildlife. Reproductive success, mortality, and dispersion are key factors to improve our understanding of how to support more diverse animal communities in urban environments. We need more research on the factors affecting the behavioral responses to urbanization of species with different life-histories. Some studies have demonstrated that urbanization has clear impacts on the behavior of wildlife species, a character that is strongly related to the success of species in a given habitat. Indeed, animals can adapt to urban ecosystems behaviorally, for example, by adjusting their food preferences, foraging behavior, anti-predator behavior, or extending the length of their reproduction season. Merging community and behavioral ecology will enable a more effective conservation of remnant semi-natural habitats in urbanized landscapes.

Variation in baseline corticosterone levels of Tree Sparrow (Passer montanus) populations along an urban gradient in Beijing, China

Rapid urbanization is a major anthropogenic pressure on bird species that rely on vegetation for food and shelter. Since the baseline corticosterone concentration (BCC) in some bird species has been found to increase slightly in response to environmental challenges, we hypothesized that urbanization could also induce an increase in BCC. To test this hypothesis, we compared the BCC of Tree Sparrow (Passer montanus) populations in five urban and two rural habitats and analyzed the relationship between BCC and the degree of urbanization. Here, we show that the BCCs of Tree Sparrow populations were strongly and positively correlated with the degree of urbanization of the habitat. Average BCC of Tree Sparrows from high-rise residential areas and a university campus were significantly higher than those from rural areas, suggesting that Tree Sparrows living in highly urbanized areas have greater environmental challenges than those in rural areas. However, the average BCC of birds from an urban park was not significantly different to that of birds at rural sites and also differed significantly from that of birds at two of the other urban sites. These results suggest that urbanization could pose environmental challenges for Tree Sparrows, a species that appears relatively well-adapted to human-modified environments. The marked variation in BCC between different urban sites indicates that conclusions drawn from data collected at single sites must be interpreted with caution.

The effects of provisioning and crop‐raiding on the diet and foraging activities of human‐commensal white‐faced Capuchins (Cebus capucinus)

Non-human primates are coming into increasingly frequent contact with humans and with human-modified environments. The potential for monkeys to survive in such modified landscapes is questionable, and is likely related to a species' behavioral plasticity, particularly as it relates to diet. In this study, I explore the ways in which white-faced capuchins (Cebus capucinus) adjust their diet and foraging behaviors in response to anthropogenic impact. I compare a troop of human-commensal monkeys and a similar troop of wild-feeding monkeys living within the Curú Wildlife Refuge in western Costa Rica for differences in overall diet composition and activity budgets to evaluate the impact of habitat change in this context. The commensal-living white-faced capuchins rely on raided coconut (Cocos nucifera) and oil palm (Elaeis guineensis) crops and provisioned or stolen human foods for over one-half of their total diet. Regardless of this highly anthropogenic diet, the two study troops do not significantly differ in their activity budgets, and the human-commensal troop maintains wild-foraging activities consistent with those of the wild-feeding troop. These data suggest that the white-faced capuchins at this site are responding to anthropogenic disturbance primarily through the exploitation of human food resources, but they do not yet appear to have lost the foraging skills required to survive in this modified landscape on their own. This study adds to our growing body of knowledge on primate survival in matrix habitats, and will hopefully inform primate management plans throughout the Neotropics.

The Spatial Ecology of Chacma Baboons (Papio ursinus) in a Human-modified Environment

Anthropogenic habitat alteration can have a dramatic effect on the spatial distribution and ranging patterns of primates. We characterized the spatial ecology of a free-living troop of chacma baboons (Papio ursinus) in a human-modified environment in the Cape Peninsula, South Africa. We used GPS and behavioral observations collected over 1 yr to quantify the troop’s home range size, habitat selection, choice of sleeping site, and foraging patterns. The troop comprised 115 individuals living in a home range of 9.50 km2, giving a density of 12.1 baboons/km2. Area use correlates positively with exotic vegetation and negatively with indigenous vegetation and altitude. The troop spent significantly more time in low-lying human-modified environments, i.e., plantations, vineyards, and urban habitat, than in indigenous vegetation that was largely restricted to steeper slopes at higher elevations. The troop slept exclusively in exotic trees, 94% of which were located in the plantation, 3% in urban habitat, and 3% in vineyards. The most consumed food items were exotic grasses, subterranean food items, and exotic pine nuts. The survival and persistence of the focal troop in close proximity to the urban edge while ≥3 neighboring troops were previously extirpated suggests that access to low-lying land in conjunction with a land-use practice that does not preclude baboon presence has been fundamental to both their survival and persistence at such a high density. The almost exclusive use of exotic vegetation both as a food source and as a safe refuge for sleeping highlights the ecological flexibility of baboons, but the systematic loss of low-lying productive land poses the single greatest threat to their continued persistence on the Cape Peninsula.

Impactos potenciais das mudanças propostas no Código Florestal Brasileiro sobre os répteis brasileiros

Avaliamos os impactos potenciais sobre a fauna brasileira de répteis (721 espécies descritas até o momento), caso sejam adotadas mudanças propostas por um substitutivo do atual Código Florestal Brasileiro. A possibilidade de compensação ambiental (obrigação legal no caso de degradação de habitats naturais) em bacias ou microbacias distintas daquelas degradadas seria uma das modificações do código vigente que prejudicaria a manutenção da diversidade de répteis. Alguns gêneros de répteis são compostos por espécies que raramente co-ocorrem em uma mesma área. Assim, ações de conservação em escalas reduzidas, em unidades naturais como microbacias, seriam mais adequadas para representar a variação da composição de espécies entre áreas. O substitutivo prevê a exclusão de topos de montanhas como Área de Preservação Permanente (APP), bem como a redução da largura das matas marginais a cursos d´água (que também são APPs). Diversos répteis brasileiros estão restritos a áreas de altitude, ao passo que outros vivem somente ou principalmente em matas de galeria ou áreas ripárias. Assim, a perda de habitat nessas áreas deve tornar alguns répteis vulneráveis a extinção. A proposta também autoriza a recuperação de Reservas Legais (RL) usando espécies de plantas exóticas. Há evidências que muitos répteis brasileiros não conseguem sobreviver em ambientes alterados pelo homem, incluindo as florestas constituídas por espécies exóticas. A proposta também tornará possível compensar RL dentro de unidades de conservação. Entretanto, as unidades de conservação existentes não seriam suficientes para a manutenção da diversidade de répteis no Brasil (principalmente porque muitas espécies têm distribuição restrita). Se adotadas, as mudanças propostas ao Código Florestal Brasileiro terão fortes impactos sobre a fauna de répteis brasileira, um importante componente do patrimônio natural do país. Além disso, moléculas com potencial farmacêutico, presentes nos venenos de muitas espécies, poderão ser perdidas.

Habitat use by western purple-faced langurs Trachypithecus vetulus nestor (Colobinae) in a fragmented suburban landscape

ESR Endangered Species Research Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsSpecials ESR 12:227-234 (2010) - DOI: https://doi.org/10.3354/esr00307 Contribution to the Theme Section 'Responses of animals to habitat alteration' Habitat use by western purple-faced langurs Trachypithecus vetulus nestor (Colobinae) in a fragmented suburban landscape R. S. Moore, K. A. I. Nekaris*, C. Eschmann Anthropology Centre for Conservation Environment and Development,School of Social Sciences and Law, Oxford Brookes University, Oxford OX3 0BP, UK *Corresponding author. Email: anekaris@brookes.ac.uk ABSTRACT: As natural habitats around the globe disappear, humans and non-human primates become increasingly engaged in complex interactions, both peaceful and hostile. Sri Lanka’s endemic western purple-faced langur Trachypithecus vetulus nestor persists in the majority of its range in complete sympatry with humans. Listed as Critically Endangered by the IUCN and one of the world’s top 25 most endangered primates, their survival appears dependent on the tolerance of humans with whom they coexist. Our aims were to augment the limited information on T. v. nestor focusing on group composition and behavioural adaptations in relation to its heavily fragmented habitat. Research was carried out in Talangama Wetlands, Sri Lanka in 2007. The 5 groups varied in size from 11 to 19 individuals Monkeys regularly used fences, rooftops, power lines, and agricultural trees. Two groups of 19 and 16 individuals had home ranges of 3.06 and 2.86 ha respectively. They consumed a variety of foods including fruits, showing dietary flexibility; the fruits and leaves of Arctocarpus heterophyllus were the langurs’ most frequently consumed foods. The langurs seem to be adapting to these human-modified environments. Notwithstanding, areas for concern include potentially fatal dangers when crossing between fragments, increasing human–primate conflict and inter-group conflict, and permanent genetic isolation. KEY WORDS: Human–wildlife conflict · Commensalism · Sri Lanka · Ethnoprimatology · Infanticide · Semnopithecus Full text in pdf format PreviousNextCite this article as: Moore RS, Nekaris KAI, Eschmann C (2010) Habitat use by western purple-faced langurs Trachypithecus vetulus nestor (Colobinae) in a fragmented suburban landscape. Endang Species Res 12:227-234. https://doi.org/10.3354/esr00307Export citation RSS - Facebook - Tweet - linkedIn Cited by Published in ESR Vol. 12, No. 3. Online publication date: September 20, 2010 Print ISSN: 1863-5407; Online ISSN: 1613-4796 Copyright © 2010 Inter-Research.

Anthropogenic influences on the spatial ecology of a semi‐arid python

Populations of carpet pythons Morelia spilota have declined across much of inland Australia, apparently because of anthropogenic disturbances, yet continue to persist in areas that have been heavily modified by humans along the eastern seaboard of Australia. To help to clarify this paradox, we undertook a radio-telemetric study of M. spilota in a semi-arid, agricultural landscape in inland Australia, making comparisons at two spatial scales. First, we compared activity and space use at the local regional level, between an area of high human modification: a homestead; and one that has experienced low human disturbance: a nearby woodland. During spring and summer, snakes inhabiting woodland environments moved more frequently and farther than those inhabiting human-modified environments. Home-range sizes did not differ between landscapes. Home ranges of M. spilota from semi-arid Australia were nearly five times smaller than those of conspecifics from coastal eastern Australia, yet daily distances moved were more than three times larger in semi-arid inland populations. Although a number of factors could explain differences in the spatial ecology between inland and coastal populations, the surprisingly ‘healthy’ population at the homestead, a modified area adjacent to relatively intact woodland, suggests the absence or reduction of processes threatening inland M. spilota at other locations. This scenario supports the idea that declines of inland M. spilota are related to habitat loss. For instance, most inland areas differ from our homestead site in having (1) greater fragmentation and thus smaller, more isolated woodland remnants; (2) a higher loss of understorey vegetation, which provides concealment from both predators and prey.

The Yucatan peninsula: biogeographical history 65 million years in the making

The fourth biennial meeting of the International Biogeography Society (IBS) in Merida, Yucatan in January 2009 represented a double opportunity for Mexican biologists. First, it fostered the integration of the large community of Mexican biogeographers with the activities of the IBS. Second, the meeting allowed us to welcome a large number of delegates from distant parts of the world who were able to visit what has been considered an obligate destination for nature lovers and cultural tourists alike: the Yucatan peninsula. As Edward O. Wilson pointed out, besides economic power every country has two additional and important types of wealth: cultural and natural. Cultural richness is a naturally embedded component of the Mexican way of life.

Influence of groundwater exploitation on the ecological status of streams in a Mediterranean system (Selva Basin, NE Spain)

The ecological status of streams depends on an equilibrium between hydrological processes and biological dynamics. Water discharge is the main requisite for a wealthy riparian habitat. Nevertheless, human practices severely affect water availability through stream water derivation and groundwater withdrawal. In this sense, impacts upon aquifer water storage and its effects on base flow generation have a significant effect on stream biology. Consequently, biological indicators will point out poor conditions resulting from such human impacts. In this paper, the effects of groundwater exploitation on stream discharge and surface water quality are evaluated and compared to biological indicators in a Mediterranean catchment. The stream–aquifer relationship is investigated by considering the hydrological context of each river reach, including human pressures, and the hydraulic head in the contiguous alluvial aquifer, where it exists. These data allow us to differentiate distinct types of reaches that are defined according to a “Stream–Aquifer relationship and chemical Pressure” (SAP) classification, which is used later on to standardize the different hydrochemical and biological features of the sampling points. Stream water and groundwater hydrochemistry are compared to depict the hydraulic behavior of the sampled watercourses during wet and dry periods. Specific elements are used as tracers of groundwater inputs, wastewater influence, or even stagnant conditions during the dry season. This dataset defines a framework to interpret the biological status of each reach based on the Iberian biological monitoring working party indicator (IBMWP). Affinities between hydrological and hydrochemical conditions with biological indicator values allow the causal effects of groundwater exploitation on stream ecology to be defined. The use of multivariate principal component analysis shows that the dataset variance is distributed according to the SAP classification, and that variable grouping is in agreement with the observed hydrological processes and their effects on biological indicator values. This work provides evidence of the importance of groundwater dynamics on biological indicators in a human-modified environment. When using the SAP classification, biological indicators acquire a broader meaning as they reveal the status of biological processes and the causal references. Such information is relevant for water management assessment within the context of the European Water Framework Directive, as it emphasizes the control of groundwater exploitation as a key parameter in the preservation of stream ecological status and the achievement of the objectives of the directive.

Environmental factors and land uses related to the naturalization of Bombus terrestris in Hokkaido, northern Japan

The buff-tailed bumblebee, Bombus terrestris, was introduced into Japan in 1991 and is now widely established in Hokkaido, northern Japan. To characterize environmental factors affecting the naturalization of B. terrestris, we examined the relationship between vegetation, land use, and bumblebee fauna at various sites in Hokkaido. Increase of human-modified environments and reduced area of forest were associated with B. terrestris inhabitation. Although agricultural fields provide a huge expanse of land for B. terrestris naturalization, environmental instability (human impacts or weather factors) sometimes leads to local population extinctions. Urban and residential areas may suffer less fluctuation and provide suitable environments for B. terrestris naturalization though the total area is rather small. Presence of the both types of human-modified environments is likely to lead the introduction of B. terrestris into new areas in Hokkaido, northern Japan.

The net ecosystem carbon exchange of human-modified environments in the Australian Capital Region

As part of a larger study to quantify and map ecosystem services in southeast Australia, we estimated carbon stored in biomass and soils and the net ecosystem carbon exchange between the land surface and the atmosphere in the Australian Capital Region (ACR). Our aim was to understand and quantify how different human-modified landscapes provide an essential ecosystem service: the exchange and storage of carbon in the landscape. Using a remote sensing based modelling methodology, we obtained values of Net Primary Productivity (NPP), total carbon in soil and biomass and carbon turnover from meteorological and terrain inputs and vegetation attributes. We obtained a set of maps of NPP, total carbon (C) storage and C-turnover for the ACR. We superimposed a land use/cover map to assign the uptake, storage and release of carbon to different land use/cover types. Our results support the hypothesis that human-intensive land uses significantly affect the ability of terrestrial ecosystems to provide an important ecosystem service in the form of carbon storage.

Fruit availability and utilisation by grey-headed flying foxes (Pteropodidae: Pteropus poliocephalus) in a human-modified environment on the south coast of New South Wales, Australia

Context. Extensive clearing and modification of habitat is likely to change many facets of the environment including climate and regional food resources. Such changes may result in changes in behaviour in highly mobile fauna, such as flying foxes. Aims.The availability of fruit resources was examined to determine whether grey-headed flying foxes (Pteropus poliocephalus) have feeding preferences related to habitat or dietary items, and whether human usage of the land around the colony site has affected the resources available. Methods. Fruit availability around a colony was monitored from December 2004 to March 2005. Night surveys and faecal analyses were undertaken to determine the distribution of feeding locations, the food species used and the food items consumed by P. poliocephalus. Key results.The amount of food available per hectare in each habitat was similar. However, we found differences in the composition of food trees and the distribution of food resources within each habitat. Ficus species were a major resource with flying foxes observed feeding in figs during every survey and figs identified in droppings over the whole period. Human-modified habitats were used throughout the study period with flying foxes observed in small patches of vegetation and in individual trees without any nearby vegetation. Conclusions. The need for maintaining vegetation, particularly Ficus species, in all areas where flying foxes are found, especially in human-modified habitats and rainforest remnants, is highlighted as this vegetation is of great importance to flying foxes. Other wildlife, such as birds and possums, may also benefit from the maintenance of this vegetation. Implications. Through management of urban resources there is the potential to prevent future conflict situations arising between humans and wildlife, such as can be seen when flying fox colonies are in close proximity to houses.

Renal pathologies in giant toads ( Bufo marinus) vary with land use

A variety of human land uses involve the release of toxins into the environment. Wildlife live alongside humans across this array of land uses and thus, are exposed to varying chemical milieus. Kidneys are the principle excretory organs for vertebrates and excessive or chronic exposure to exogenous toxins can lead to renal pathology and renal failure. Although studies have linked chemical exposure to specific renal diseases across diverse taxa, none compare renal lesions occurring in wildlife living in different types of human-modified landscapes. We identify lesions characteristic of renal stress, including toxin exposure, in 82 giant toad ( Bufo marinus) males living in habitats ranging from suburban to agricultural. In a previous study [McCoy K.A., Bortnick L.J., Campbell C.M., Hamlin H.J., Guillette L.J., Jr., St. Mary C.M. Agriculture Alters Gonadal Form and Function in Bufo marinus. Environ Health Persp; in press.], these individuals were examined for gonadal abnormalities, which were significantly and positively associated with percentage of agriculture at the collection site. Thus, we hypothesized the same association for renal abnormalities. We scored gross anatomical abnormalities and used light microscopy to identify tubular and interstitial lesions that have been associated with toxicant exposure in other organisms, including humans. Renal lesions indicative of tubular disease were observed at one suburban and two agricultural sites, whereas interstitial lesions were most severe at one agricultural site. Although there was no relationship between frequency of renal disease and proportion of agriculture in the collection vicinity, the renal lesions we identify are consistent with toxin exposure and are similar to those found in human drug abusers and patients suffering medication-induced nephropathy. This is the first study to describe renal lesions in a wild amphibian species and investigate the distribution of renal lesions across human altered landscapes. Indentifying the chemicals inducing renal lesions across these landscapes, their toxicological mechanisms, and their implications on wildlife health will help us devise strategies to mitigate the impacts of toxins on humans and animals living in human-modified environments.

Spatial and Temporal Variation in the Diet of Coyotes in the Chicago Metropolitan Area

Coyotes (Canis latrans) are an opportunistic predator that have adapted to many human-modified environments. Conflicts between coyotes and humans are an increasing concern for managers in urban areas. We examined the spatial and temporal utilization and availability of natural and human-associated food for coyotes in the Chicago metropolitan area, Illinois, USA. We collected 1429 coyote scats from May 2000 to December 2002, and conducted prey surveys in 2002, in 4 sites that varied in their degree of urban development. Dominant food items included small rodents, white-tailed deer (Odocoileus virginianus), fruit, eastern cottontail (Sylvilagus floridanus) and birds. Their availability and occurrence in scats varied among sites and seasons. The occurrence of human-associated food items, which was only found in significant amounts in the most developed site, varied seasonally (2–25%). Because coyotes in less-developed areas had lower dietary diversity, these coyotes may have to venture into developed areas when there is a decline in the abundance of major prey species for that specific area.

Movement of Dengue Vectors Between the Human Modified Environment and an Urban Forest in Rio de Janeiro

The movement of Aedes aegypti (L.) and Aedes albopictus (Skuse) females between sylvatic and urban environments was investigated by marking, releasing, and recapturing adults and by identifying rubidium (Rb)-marked eggs of females that were released after taking a bloodmeal containing RbCl. When released in the forest, Ae. albopictus females flew as far as 1,000 m and reached houses within 1 wk. When Ae. albopictus were released close to houses, most females were recaptured near the release point, and Rb-marked eggs were found 1,000 m away in the forest only once, 35 d after the release. These differing patterns of movement may suggest a preference of Ae. albopictus for the human-modified environment. Ae. aegypti, however, showed low tendency to disperse into the forest. The capacity of Ae. albopictus females to disperse from a sylvatic into a human-modified environment suggests that this species may play a role in the dissemination of forest-restricted pathogens, such as yellow fever virus.

Movement of Dengue Vectors Between the Human Modified Environment and an Urban Forest in Rio de Janeiro

The movement of Aedes aegypti (L.) and Aedes albopictus (Skuse) females between sylvatic and urban environments was investigated by marking, releasing, and recapturing adults and by identifying rubidium (Rb)-marked eggs of females that were released after taking a bloodmeal containing RbCI. When released in the forest, Ae. albopictus females flew as far as 1000 m and reached houses within 1 wk. When Ae. albopictus were released close to houses, most females were recaptured near the release point, and Rb-marked eggs were found 1000 m away in the forest only once, 35 d after the release. These differing patterns of movement may suggest a preference of Ae. albopictus for the human-modified environment. Ae. aegypti, however, showed low tendency to disperse into the forest. The capacity of Ae. albopictus females to disperse from a sylvatic into a human-modified environment suggests that this species may play a role in the dissemination of forest-restricted pathogens, such as yellow fever virus.

Urban Food Webs: Predators, Prey, and the People Who Feed Them

A prevailing image of the city is of the steel and concrete downtown skyline. The more common ex‐ perience of urban residents, however, is a place of irrigated and fertilized green spaces, such as yards, gardens, and parks, surrounding homes and business‐ es where people commonly feed birds, squirrels, and other wildlife. Within these highly human-modified environments, researchers are becoming increasingly curious about how fundamental ecological phenom‐ ena play out, such as the feeding relationships among species. While food webs have long provided a tool for organizing information about feeding relation‐ ships and energy flows through natural habitats, they have not been applied to urban ecosystems until re‐ cently (Faeth et al. 2005).