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Peri-urban rivers have been subjected to poor environmental management, especially in developing countries, due to urban expansion and channel transformation in the context of a lack of public conservation policies. As an example, Mexico City, the second largest city in the world, has a socioenvironmental mosaic that allows the evaluation of ecosystem services (ES) associated with aquatic ecosystems amid urbanistic pressures. The main objective of this research was to identify sites with the greatest ES potential supplied by conserved areas that are in a rural-urban transition using the ecological traits of riparian bioindicators, including eco-physiological metrics of communities and assemblages and hydromorphological quality. The aquatic ES most influenced by the peri-urban context was nutrient cycling through the incorporation of organic matter from the riparian ecosystem into the river. Water quantity was also influenced, due to local extraction and structures such as gabion dams. The support and provision ES were sensitive to changes in the geomorphology configuration. In conclusion our results showed that the biological morpho-functional indicators of blue ES were an objective tool to assess the state of river functioning and translate these functions into the language of decision makers. Finally, we determined that the ES provision into the Mexico Basin mainly responds to three major factors: physical characteristics, hydromorphological functioning and the functional ecology of organisms.

Behavioural adaptations are recognized as crucial determinants for successful establishment and persistence of animal populations in a novel urban environment. Here, we examined mechanisms responsible for the development of urban behavioural type in a common waterbird, the Eurasian coot Fulica atra. We compared the behaviour of coots from a rural population and two urban populations that differed in the timing of colonization event (1960s vs. 2000s). We found that some behavioural characters associated with urban life (aggression during nest defence and boldness towards humans during foraging) were more strongly expressed in the older urban population when compared with the recently established urban population. By contrast, coots from the two urban populations showed a similar likelihood of exploiting human-derived food resources, as well as they showed similar levels of physiological stress. Urban coots were generally more aggressive, bolder, and less stressed than their rural conspecifics. Large behavioural and physiological divergence of coots from the recently established urban population and their rural conspecifics suggested that phenotypic plasticity and phenotype sorting may play a key role in the initial stages of urban colonization. On the other hand, increasing expression of boldness and aggression with the time since urbanization may suggest the role of microevolutionary adaptation in response to novel selective forces associated with the urban environment. Our results indicate that a combination of different processes (phenotypic plasticity, phenotype sorting, and microevolution) can determine successful colonization of urban areas by the Eurasian coots, and possibly other bird species.

Our essay responds to the critique of Dooling et al. (Urban Ecosystems in press, 2007) of our previously published article “Goal attainment in urban ecology research: a bibliometric review 1975-2004 (Young and Wolf, Urban Ecosystems, 9:179–193, 2006). We identify our critics’ concerns as rooted in a project of deconstruction of scientific inquiry and a redefinition of the boundaries separating academic disciplines from each other and science from society. While we identify important differences with our critics, we largely support this critical project, as evidenced by our previously published empirical research. In exploring the relationship between critical and positivist approaches to urban ecology research and how we might work toward an integration of nature and society in thought and action, we defend pragmatic approaches to empirical research as well as disciplinary projects as legitimate and essential elements of urban ecology research. We argue in favor of theoretical and methodological pluralism. Rather than define urban ecology through exclusionary projects that would limit the scope and significance of urban ecology research, we reaffirm our call for diverse sets of actors inside and outside university settings to engage and support each other in order to develop and strengthen analysis and pursuit of sustainability.

Foraging decisions reflect a trade-off between the benefits of acquiring food and the costs of movement. Changes in the biotic and abiotic environment associated with urbanization can alter this trade-off and modify foraging decisions. We experimentally manipulated foraging opportunities for two Anolis lizard species – the brown anole (A. sagrei) in Florida and the crested anole (A. cristatellus) in Puerto Rico – to assess whether foraging behavior differs between habitats varying in their degree of urbanization. In both urban and natural forest habitats, we measured the latency of perched anoles to feed from an experimental feeding tray. We manipulated perch availability and predator presence, while also taking into account population (e.g., conspecific density) and individual-level factors (e.g., body temperature) to evaluate whether and how these contribute to between-habitat differences in foraging behavior. In both species, urban anoles had longer latencies to feed and lower overall response rates compared to lizards from forests. Urban anoles were also larger (i.e., snout-vent length and mass) in both species and urban A. sagrei were in better body condition than the natural forest population. We postulate that the observed patterns in foraging behavior are driven by differences in perceived predation risk, foraging motivation, or neophobia. Although we are unable to identify the mechanism(s) driving these differences, the substantial differences in urban versus forest anole foraging behavior emphasizes the importance of understanding how urbanization influences animal populations and their persistence in anthropogenically-modified environments.

Vegetated roofs are hoped to benefit urban wildlife, yet there are few empirical results regarding the conservation potential of such roofs. In this paper, we focus on arthropods on vegetated roofs. We vacuum sampled 17 succulent, meadow or succulent-meadow roofs, in Helsinki, Finland, and used order to species level information together with trait data to describe the communities. We evaluated the importance of biophysical roof characteristics on shaping arthropod assemblages to provide information concerning roof designs that promote rich arthropod fauna. Arthropod communities differed between the three roof types and the influence of roof variables varied between and within arthropod orders. The main local drivers of arthropod abundance across the individually analysed taxa were roof height and vegetation, with mainly positive effects of height (up to 11 m) and litter cover, and mainly negative effects of grass cover. Based on trait data from true bugs, spiders and ants, the roofs consisted mainly of common dispersive species that are generalist feeders and associated with dry open habitats or have wide habitat tolerance. We found one true bug species new to the country and assume that it arrived with imported vegetation. Based on these findings, vegetated roofs of varying height and size benefit common generalists and fauna of open dry habitats, but seem to lack rare native specialists and may introduce non-natives if imported plant material is used. Because the responses to vegetation characteristics are taxon-specific, high diversity of roof vegetation types would benefit arthropod conservation.

Our study focuses on the spatial ecology and seasonal habitat use of two aquatic turtles in order to understand the manner in which upland habitat use by humans shapes the aquatic activity, movement, and habitat selection of these species in an urban setting. We used radiotelemetry to follow 15 female Graptemys geographica (common map turtle) and each of ten male and female Trachemys scripta (red-eared slider) living in a man-made canal within a highly urbanized region of Indianapolis, IN, USA. During the active season (between May and September) of 2002, we located 33 of the 35 individuals a total of 934 times and determined the total range of activity, mean movement, and daily movement for each individuals. We also analyzed turtle locations relative to the upland habitat types (commercial, residential, river, road, woodlot, and open) surrounding the canal and determined that the turtles spent a disproportionate amount of time in woodland and commercial habitats and avoided the road-associated portions of the canal. We also located 21 of the turtles during hibernation (February 2003), and determined that an even greater proportion of individuals hibernated in woodland-bordered portions of the canal. Our results clearly indicate that turtle habitat selection is influenced by human activities; sound conservation and management of turtle populations in urban habitats will require the incorporation of spatial ecology and habitat use data.

Developing effective butterfly monitoring strategies is key to understanding how butterflies interact with urban environments, and, in turn, to developing local conservation practices. We investigated two urban habitat types (public gardens and restored/reconstructed prairies) and compared three survey methods (Pollard transects, purposive point counts, and random point counts) to determine which was most productive for detecting butterflies and assessing family diversity. We conducted 66 butterfly surveys by using each method (198 total) from May through September in 2015 and 2016 at six sites (three public gardens and three prairies) in Ames, Ankeny and Des Moines, Iowa. All survey methods were used on 11 sampling dates at each site. Overall, we observed 2,227 butterflies representing 38 species: 1,076 in public gardens and 1,151 in prairie areas. We used a smaller data set standardized for survey effort, including 1,361 of these sightings, to compare survey methods and habitat types. Although there were no significant differences in number of butterfly sightings between the two habitats, more sightings (798) were documented by using purposive point counts when compared to Pollard transects (297) or random point counts (266) (for both comparisons, p < 0.0001). Occupancy modeling also indicated that purposive point counts were most effective in detecting certain species of butterflies, most notably those within the Pieridae (whites, sulphurs) and Papilionidae (swallowtails). We conclude that public gardens and restored/reconstructed prairies in urban settings can provide important butterfly habitat, and that purposive point-count surveys are most effective for detecting butterflies in these relatively small-scale landscape features.

The tree population within the City of Syracuse was assessed using a random sampling of plots in 1999, 2001 and 2009 to determine how the population and the ecosystem services these trees provide have changed over time. Ecosystem services and values for carbon sequestration, air pollution removal and changes in building energy use were derived using the i-Tree Eco model. In addition, photo interpretation of aerial images was used to determine changes in tree cover between the mid-1990s and 2009. Between the mid-1990s and 2003, tree cover in Syracuse exhibited a decline from 27.5 to 25.9 %, but subsequently increased to 26.9 % by 2009. The total tree population exhibited a similar pattern, dropping from 881,000 trees in 1999 to 862,000 in 2001, and then increasing to 1,087,000 trees in 2009. Most of this increase in the urban tree population is due to invasive or pioneer trees species, particularly Rhamnus cathartica, which has more than tripled in population between 2001 and 2009. Insects such as gypsy moth and emerald ash borer pose a substantial risk to altering future urban forest composition. The annual ecosystem services provided by the urban forest in relation to carbon sequestration, air pollution removal and reduction in building energy use are estimated at about $2.4 million per year. An improved understanding of urban forests and how they are changing can facilitate better management plans to sustain ecosystem services and desired forest structure for future generations.

Urbanization is spreading all over the world, with more than half of the people now living in urban ecosystems. Pollutants such as metals have continuously been introduced into ecosystems as a consequence of urbanization and industrial processes. Metals can bioaccumulate in tissues of organisms. Therefore, the selection of ecological compartments such as birds as bio-indicator species can be a proper approach to monitor pollution in cities. This study aimed to measure concentrations of lead in the lungs and feathers of the house sparrow (Passer domesticus) and investigate the possibility of applying this species for air pollution monitoring in Tehran, Iran. In July and August of 2020, 50 bird specimens were collected from five regions of Tehran (north, south, east, west, and central) and 10 birds from Alborz region (as the control station). The lead concentration was measured by using a FAAS instrument after acid digestion. The results showed that the average lead concentration in feathers of five regions of Tehran (North: 42.95 ± 23.57, Central: 43.59 ± 9.58, South: 35.42 ± 3.38, East: 22.91 ± 3.24, and West: 34.36 ± 11.98 µg/g) were higher than those of the control station (14.40 ± 2.97 µg/g). Significant differences were observed between lead concentration in feathers of the birds collected from the control station and those of central, south and west of Tehran. Lead concentration in the birds’ lungs in all regions of Tehran (North: 72.65 ± 17.55, Central: 20.76 ± 3.02, East: 17.88 ± 1.74, and West: 30.19 ± 13.04 µg/g) except south (13.17 ± 2.14 µg/g) were higher than the control group (14.57 ± 1.94 µg/g). However, this difference was only significant between the birds of the control station and those of north of Tehran. In this study, no significant differences were observed between lead concentrations in male and female as well as adult and juvenile sparrows. Also, no significant correlation was observed between tissue accumulation of lead in feathers and lungs. This study suggests that feathers can be used as a useful indicator of local air pollution.