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J.A. Bissonette

Publications and source records attributed to J.A. Bissonette.

13 recordsLinked to original sources
USGS2010

Do well-connected landscapes promote road-related mortality?

Cost surface (CS) models have emerged as a useful tool to examine the interactions between landscapes patterns and wildlife at large-scale extents. This approach is particularly relevant to guide conservation planning for species that show vulnerability to road networks in human-dominated landscapes. In this study, we measured the functional connectivity of the landscape in southern Portugal and examined how it may be related to stone marten road mortality risk. We addressed three questions: (1) How different levels of landscape connectivity influence stone marten occurrence in montado patches? (2) Is there any relation between montado patches connectivity and stone marten road mortality risk? (3) If so, which road-related features might be responsible for the species’ high road mortality? We developed a series of connectivity models using CS scenarios with different resistance values given to each vegetation cover type to reflect different resistance to species movement. Our models showed that the likelihood of occurrence of stone marten decreased with distance to source areas, meaning continuous montado. Open areas and riparian areas within open area matrices entailed increased costs. We found higher stone marten mortality on roads in well-connected areas. Road sinuosity was an important factor influencing the mortality in those areas. This result challenges the way that connectivity and its relation to mortality has been generally regarded. Clearly, landscape connectivity and road-related mortality are not independent.

European Journal of Wildlife Research↗
USGS2009

Summer spatial patterning of chukars in relation to free water in Western Utah

Free water is considered important to wildlife in arid regions. In the western United States, thousands of water developments have been built to benefit wildlife in arid landscapes. Agencies and researchers have yet to clearly demonstrate their effectiveness. We combined a spatial analysis of summer chukar (Alectoris chukar) covey locations with dietary composition analysis in western Utah. Our specific objectives were to determine if chukars showed a spatial pattern that suggested association with free water in four study areas and to document summer dietary moisture content in relation to average distance from water. The observed data for the Cedar Mountains study area fell within the middle of the random mean distance to water distribution suggesting no association with free water. The observed mean distance to water for the other three areas was much closer than expected compared to a random spatial process, suggesting the importance of free water to these populations. Dietary moisture content of chukar food items from the Cedar Mountains (59%) was significantly greater (P < 0.05) than that of birds from Box Elder (44%) and Keg-Dugway (44%). Water developments on the Cedar Mountains are likely ineffective for chukars. Spatial patterns on the other areas, however, suggest association with free water and our results demonstrate the need for site-specific considerations. Researchers should be aware of the potential to satisfy water demand with pre-formed and metabolic water for a variety of species in studies that address the effects of wildlife water developments. We encourage incorporation of spatial structure in model error components in future ecological research. ?? Springer Science+Business Media B.V. 2009.

Landscape Ecology↗
USGS2009

Spatial-temporal patterns in Mediterranean carnivore road casualties: Consequences for mitigation

Many carnivores have been seriously impacted by the expansion of transportation systems and networks; however we know little about carnivore response to the extent and magnitude of road mortality, or which age classes may be disproportionately impacted. Recent research has demonstrated that wildlife-vehicle-collisions (WVC) involving carnivores are modulated by temporal and spatial factors. Thus, we investigated road mortality on a guild of small and medium-sized carnivores in southern Portugal using road-kill data obtained from a systematic 36 months monitoring period along highways (260 km) and national roads (314 km) by addressing the following questions: (a) which species and age class are most vulnerable to WVC? (b) are there temporal and/or spatial patterns in road-kill? and (c) which life-history and/or spatial factors influence the likelihood of collisions? We recorded a total of 806 carnivore casualties, which represented an average of 47 ind./100 km/year. Red fox and stone marten had the highest mortality rates. Our findings highlight three key messages: (1) the majority of road-killed individuals were adults of common species; (2) all carnivores, except genets, were more vulnerable during specific life-history phenological periods: higher casualties were observed when red fox and stone marten were provisioning young, Eurasian badger casualties occurred more frequently during dispersal, and higher Egyptian mongoose mortality occurred during the breeding period; and (3) modeling demonstrated that favorable habitat, curves in the road, and low human disturbance were major contributors to the deadliest road segments. Red fox carcasses were more likely to be found on road sections with passages distant from urban areas. Conversely, stone marten mortalities were found more often on national roads with high of cork oak woodland cover; Egyptian mongoose and genet road-kills were found more often on road segments close to curves. Based on our results, two key mitigation measures should help to reduce WVC in Portugal. The first involves the improvement of existing crossings with buried and small mesh size fence to guide the individuals towards to the passages, in road segments with high traffic volume (>1200 vehicles/night) and located in preferred carnivore habitats. The second mitigation involves cutting or removal of dense vegetation in verges of road segments with curves to aid motorists in seeing animals about to cross. ?? 2008 Elsevier Ltd.

Biological Conservation↗
USGS2009

The effects of fire on avian communities: Spatio-temporal attributes of the literature 19122003

We reviewed the temporal, geographic, and biogeographic distribution, as well as relevant research and publication attributes, of 512 documents addressing the effects of fire on avian communities, to provide an assessment of the scope of this literature and recommendations for future research. We summarized relevant attributes of all documents to identify patterns that were then tested against appropriate null models. Most documents reported on original research, with the literature evenly divided between studies investigating controlled fire and those reporting on uncontrolled wildfires. Conceptual reviews made up the second largest category; methodological reviews, bibliographies, and meta-analyses were rare. Although the literature examined spans nearly a century, most documents were published within the last 15 years, with new literature being added at an increasing rate. However, increases seem to be skewed towards original research at the expense of synthesis. An overwhelming majority of documents were published in peer-reviewed scientific journals and in English. Other important publication outlets included MS and PhD theses and conference proceedings. The spatial distribution of documents by continent and biogeographic domain and division differed significantly from expectations based on land area. Future research on avian community response to fire should focus on (1) continued synthesis, emphasizing methodological reviews, bibliographies, and North America; (2) increasing research efforts in areas currently underrepresented in the literature, including Africa, Asia, and South and Central America; and (3) meta-analyses. ?? 2009 IAWF.

International Journal of Wildland Fire↗
USGS2009

Road zone effects in small-mammal communities

Our study focused on the putative effects of roads on small-mammal communities in a high desert region of southern Utah. Specifically, we tested whether or not roads create adjacent zones characterized by lower small- mammal densities, abundance, and diversity. We sampled abundance of small mammals at increasing distances from Interstate 15 during two summers. We recorded 11 genera and 13 species. We detected no clear abundance, density, or diversity effects relative to distance from the road. Only two of 13 species were never captured near roads. The abundance of the remaining 11 small mammal species was either similar at different distances from the road or higher closer to the road. We conclude that although roads may act as barriers and possible sources of mortality, adjacent zones of vegetation often provide favorable microhabitat in the desert landscape for many small mammals. ?? 2009 by the author(s).

Ecology and Society↗
USGS2008

Relative importance of habitat area and isolation for bird occurrence patterns in a naturally patchy landscape

There is debate among ecologists about whether total habitat area or patch arrangement contributes most to population and/or community responses to fragmented or patchy landscapes. We tested the relative effects of patch area and isolation for predicting bird occurrence in a naturally patchy landscape in the Bear River Mountains of Northern Utah, USA. We selected focal patches (mountain meadows) ranging in elevation from 1,920 to 2,860 m and in size from 0.6 to 182 ha. Breeding birds were sampled in each focal meadow during the summers of 2003 and 2004 using variable-distance point transects. Logistic regression and likelihood-based model selection were used to determine the relationship between likelihood of occurrence of three bird species (Brewer's sparrow, vesper sparrow, and white-crowned sparrow) and area, isolation, and proximity metrics. We used model weights and model-averaged confidence intervals to assess the importance of each predictor variable. Plots of area versus isolation were used to evaluate complex relationships between the variables. We found that meadow area was the most important variable for explaining occurrence for two species, and that isolation was the most important for the other. We also found that the absolute distance was more appropriate for evaluating isolation responses than was the species-specific proximity metric. Our findings add clarity to the debate between ecologists regarding the relative importance of area and isolation in species responses to patchy landscapes.

Landscape Ecology↗
USGS2008

Restoring habitat permeability to roaded landscapes with isometrically-scaled wildlife crossings

Globally, human activities impact from one-third to one-half of the earth's land surface; a major component of development involves the construction of roads. In the US and Europe, road networks fragment normal animal movement patterns, reduce landscape permeability, and increase wildlife-vehicle collisions, often with serious wildlife population and human health consequences. Critically, the placement of wildlife crossing structures to restore landscape connectivity and reduce the number of wildlife-vehicle collisions has been a hit-or-miss proposition with little ecological underpinning, however recent important developments in allometric scaling laws can be used to guide their placement. In this paper, we used cluster analysis to develop domains of scale for mammalian species groups having similar vagility and developed metrics that reflect realistic species movement dynamics. We identified six home range area domains; three quarters of 102 species clustered in the three smallest domains. We used HR0.5 to represent a daily movement metric; when individual species movements were plotted against road mile markers, 71.2% of 72 species found in North America were included at distances of ???1 mi. The placement of wildlife crossings based on the HR0.5 metric, along with appropriate auxiliary mitigation, will re-establish landscape permeability by facilitating wildlife movement across the roaded landscape and significantly improve road safety by reducing wildlife vehicle collisions.

Biological Conservation↗
USGS2004

Benefits and impacts of road removal

Road removal is being used to mitigate the physical and ecological impacts of roads and to restore both public and private lands. Although many federal and state agencies and private landowners have created protocols for road removal and priorities for restoration, research has not kept pace with the rate of removal. Some research has been conducted on hydrologic and geomorphic restoration following road removal, but no studies have directly addressed restoring wildlife habitat. Road removal creates a short-term disturbance which may temporarily increase sediment loss. However, long-term monitoring and initial research have shown that road removal reduces chronic erosion and the risk of landslides. We review the hydrologic, geomorphic, and ecological benefits and impacts of three methods of road removal, identify knowledge gaps, and propose questions for future research, which is urgently needed to quantify how effectively road removal restores terrestrial, riparian, and aquatic habitat and other ecosystem processes.

Frontiers in Ecology and the Environment↗
USGS2002

Fragmentation: Is the message clear?

In this paper, we briefly discuss some of the fundamental problems arising from the inherent complexity of larger-scale ecological systems. We examine the tenuous assumption of a direct correspondence between ecological data and theory, we comment on a recent report that evaluated the efficacy of fragmentation experiments, and we briefly assess its implications for ecological research and conservation practice on the landscape scale.

Ecology and Society↗
USGS2002

Scaling roads and wildlife: The Cinderella principle

It is clear that a reduction in both direct and indirect effects of roads and road networks must be the goal of management agencies. However, increased permeability of roaded landscapes can only be achieved by up-front planning and subsequent mitigative actions. The key is to understand that roads must be made permeable to the movement of animals. More profoundly, ecosystem services, i.e., clean water, clean air, uncontaminated soil, natural landscapes, recreation opportunities, abundant wildlife, and life sustaining ecological processes must not be seriously impacted. In other words, quality of life as measured by ecosystem services should be a major component of the planning process when roads are constructed or improved. Mitigative structures exist to increase permeability of roads. Wildlife overpasses and underpasses, often referred to as ecoducts or green bridges, with associated structures to enable larger animals to exit the road right of way, e.g., earthen escape ramps (BISSONETTE and HAMMER, 2001), various culvert designs for smaller animals including badger pipes and amphibian and reptile tunnels, and fish ladders are but a small sampling of the structures already in place around the world. What is needed is attention to the big picture. Landscapes need to be reconnected and made more permeable. Responsible agencies and organizations need to be aggressive about promoting mitigations and a conservation ethic into road planning. Only with a broad based effort between a concerned public, a database to work from, and a willingness of responsible agencies, will the now very large virtual footprint of roads and road networks be reduced to more closely approximate the physical footprint. By embracing the Cinderella Principle of making the virtual shoe fit more closely the actual physical footprint of roads, we will be able to achieve a closer connection with ecological harmony with its resultant effect of abundant wildlife.

Conference Paper↗
USGS1999

Effects of saline drinking water on early gosling development

Relatively high levels of saline drinking water may adversely affect the growth, development, and survival of young waterfowl. Saline drinking water was suspect in the low survival rate of Canada goose (Branta canadensis) goslings at Fish Springs National Wildlife Refuge (FSNWR) in western Utah. Hence, we investigated the effects of saline drinking water on the survival and growth of captive, wild-strain goslings from day 1-28 following hatch. We compared survival and growth (as measured by body mass, wing length, and culmen length) between a control group on tap water with a mean specific conductivity of 650 μS/cm, and 2 saline water treatments: (1) intermediate level (12,000 μS/cm), and (2) high level (18,000 μS/cm). Gosling mortality occurred only in the 18,000 μS/cm treatment group (33%; n = 9). Slopes of regressions of mean body mass, wing length, and culmen length on age were different from each other (P < 0.05), except for culmen length for the intermediate and high treatment levels. We predict that free-ranging wild goslings will experience mortality at even lower salinity levels than captive goslings because of the combined effects of depressed growth and environmental stresses, including hot desert temperatures and variable food quality over summer.

Journal of Wildlife Management↗
USGS1998

Changes in land use as a possible factor in Mourning Dove population decline in Central Utah

Mourning Dove (Zenaida macroura) population indices for the western United States have declined significantly since 1966. Based on data collected in 1951-1952, in Fillmore, Utah, we examined whether there had been a local decline in the dove population index since the original data were collected. We then determined whether habitat had been altered, identified which foraging habitats doves preferred, and assessed whether changes in land use could be responsible, in part, for a decline in the local population index. We found that dove population indices declined 72% and 82% from 1952-1992 and 1952-1993, respectively. The most dramatic change in habitat was an 82% decline in land devoted to dry land winter wheat production and a decline in livestock feed pens. Doves foraged primarily in harvested wheat fields, feed pens, and weedy patches. We hypothesize that a decrease in wheat availability during the spring and the consolidation of the livestock industry have contributed to a population decline of Mourning Doves in central Utah.

Journal of Field Ornithology↗