Local government planning agencies play an important role in conserving biodiversity in human-altered landscapes. Such agencies frequently have a limited knowledge of wildlife biology and few resources to carry out research, and therefore require simple, practical guidelines for biodiversity conservation. We propose a landscape design framework for biodiversity conservation that is sequential, prescriptive, and supported by current landscape ecological science. Unlike existing guidelines, our framework can be implemented in any given landscape using only land cover data and it explicitly considers constraints on land use planning. The steps of our framework, in the order in which they should be implemented are: (1) select land cover data and decide which land cover classes constitute unaltered or altered land covers; (2) list the constraints on land use planning (e.g., economic, social) that exist for the landscape; (3) maximize the total amount and diversity of unaltered land cover, especially near water; (4) minimize human disturbance within altered land cover, especially near water; and (5) aggregate altered land covers associated with high-intensity land uses, especially away from water. We illustrate the utility of our approach by applying it to a hypothetical landscape and comparing the outcome to those from the application of traditional ecological guidelines to inform land use planning. (C) 2014 Elsevier B.V. All rights reserved.

Mechanical operations such as mowing, tilling, seeding, and harvesting are well-known sources of direct avian mortality in agricultural fields. However, there are currently no mortality rate estimates available for any species group or larger jurisdiction. Even reviews of sources of mortality in birds have failed to address mechanical disturbance in farm fields. To overcome this information gap we provide estimates of total mortality rates by mechanical operations for five selected species across Canada. In our step-by-step modeling approach we (i) quantified the amount of various types of agricultural land in each Bird Conservation Region (BCR) in Canada, (ii) estimated population densities by region and agricultural habitat type for each selected species, (iii) estimated the average timing of mechanical agricultural activities, egg laying, and fledging, (iv) and used these values and additional demographical parameters to derive estimates of total mortality by species within each BCR. Based on our calculations the total annual estimated incidental take of young ranged from similar to 138,000 for Horned Lark (Eremophila alpestris) to as much as similar to 941,000 for Savannah Sparrow (Passerculus sandwichensis). Net losses to the fall flight of birds, i. e., those birds that would have fledged successfully in the absence of mechanical disturbance, were, for example similar to 321,000 for Bobolink (Dolichonyx oryzivorus) and similar to 483,000 for Savannah Sparrow. Although our estimates are subject to an unknown degree of uncertainty, this assessment is a very important first step because it provides a broad estimate of incidental take for a set of species that may be particularly vulnerable to mechanical operations and a starting point for future refinements of model parameters if and when they become available.

Avian mortality at communication towers in the continental United States and Canada is an issue of pressing conservation concern. Previous estimates of this mortality have been based on limited data and have not included Canada. We compiled a database of communication towers in the continental United States and Canada and estimated avian mortality by tower with a regression relating avian mortality to tower height. This equation was derived from 38 tower studies for which mortality data were available and corrected for sampling effort, search efficiency, and scavenging where appropriate. Although most studies document mortality at guyed towers with steady-burning lights, we accounted for lower mortality at towers without guy wires or steady-burning lights by adjusting estimates based on published studies. The resulting estimate of mortality at towers is 6.8 million birds per year in the United States and Canada. Bootstrapped subsampling indicated that the regression was robust to the choice of studies included and a comparison of multiple regression models showed that incorporating sampling, scavenging, and search efficiency adjustments improved model fit. Estimating total avian mortality is only a first step in developing an assessment of the biological significance of mortality at communication towers for individual species or groups of species. Nevertheless, our estimate can be used to evaluate this source of mortality, develop subsequent per-species mortality estimates, and motivate policy action.

Birds migrating to and from breeding grounds in the United States and Canada are killed by the millions in collisions with lighted towers and their guy wires. Avian mortality at towers is highly variable across species, and the importance to each population depends on its size and trajectory. Building on our previous estimate of avian mortality at communication towers, we calculated mortality by species and by regions. To do this, we constructed a database of mortality by species at towers from available records and calculated the mean proportion of each species killed at towers within aggregated Bird Conservation Regions. These proportions were combined with mortality estimates that we previously calculated for those regions. We then compared our estimated bird mortality rates to the estimated populations of these species in the United States and Canada. Neotropical migrants suffer the greatest mortality; 97.4% of birds killed are passerines, mostly warblers (Parulidae, 58.4%), vireos (Vireonidae, 13.4%), thrushes (Turdidae, 7.7%), and sparrows (Emberizidae, 5.8%). Thirteen birds of conservation concern in the United States or Canada suffer annual mortality of 1-9% of their estimated total population. Of these, estimated annual mortality is >2% for Yellow Rail (Coturnicops noveboracensis), Swainson's Warbler (Limnothlypis swainsonii), Pied-billed Grebe (Podilymbus podiceps), Bay-breasted Warbler (Setophaga castanea), Golden-winged Warbler (Vermivora chrysoptera), Worm-eating Warbler (Helmitheros vermivorum), Prairie Warbler (Setophaga discolor), and Ovenbird (Seiurus aurocapilla). Avian mortality from anthropogenic sources is almost always reported in the aggregate ("number of birds killed"), which cannot detect the species-level effects necessary to make conservation assessments. Our approach to per species estimates could be undertaken for other sources of chronic anthropogenic mortality. (C) 2012 Elsevier Ltd. All rights reserved.

Although human-modified landscapes are characterized by the loss of natural habitats, new habitats also can be created and exploited by many species. The importance of landscape change to invertebrate associations (particularly host-parasite associations) is understudied. Our objective was to determine whether prevalence and intensity of gregarine parasitism in the damselfly Ischnura verticalis (Say) (Odonata: Coenagrionidae) differed between 17 artificial and 7 natural wetlands in landscapes that varied in amount of forest and wetland cover and road density determined at spatial extents of 500 m and 1 km from each wetland. Wetlands were located in and around Ottawa, Ontario, and Gatineau, Quebec, Canada. Wetland type did not account for significant variation in principal components based on forest and wetland cover and road density at either spatial extent. Gregarine prevalence was higher in damselflies collected from natural wetlands than in those collected from artificial wetlands and was positively associated with increasing forest cover. In contrast, gregarine intensity was inversely related to road density. Our results suggest that parasitism of damselflies by gregarines is associated with wetland type and landscape characteristics, although the mechanisms producing such relationships are unknown.

The effect of artificial habitat in altered landscapes on species interactions and their suite of enemies is largely unknown. Water mites have been associated with reduced fitness of model damselflies. Mite parasitism was variable, but higher for Ischnura verticalis damselflies from natural, than from artificial, wetlands in the same region. There were no differences in timing of sampling, temperature during sampling, or host age or sex composition of samples between wetland types. Landscape structure might constrain mite presence or abundance at wetland sites or wetland type might be a better predictor of mites, based on factors such as prey abundance. Fewer mites on damselflies from numerous artificial wetlands means that the strength of parasite‐mediated selection is likely less than would be inferred if only natural wetlands were surveyed. Such effects of human changes in habitats on host species probably occur often.

Roads and traffic affect animal populations detrimentally in four ways: they decrease habitat amount and quality, enhance mortality due to collisions with vehicles, prevent access to resources on the other side of the road, and subdivide animal populations into smaller and more vulnerable fractions. Roads will affect persistence of animal populations differently depending on (1) road avoidance behavior of the animals (i.e., noise avoidance, road surface avoidance, and car avoidance); (2) population sensitivity to the four road effects; (3) road size; and (4) traffic volume. We have created a model based on these population and road characteristics to study the questions: (1) what types of road avoidance behaviors make populations more vulnerable to roads?; (2) what types of roads have the greatest impact on population persistence?; and (3) how much does the impact of roads vary with the relative population sensitivity to the four road effects?Our results suggest that, in general, the most vulnerable populations are those with high noise and high road surface avoidance, and secondly, those with high noise avoidance only. Conversely, the least vulnerable populations are those with high car avoidance only, and secondly, high road surface and high car avoidance. Populations with low overall road avoidance and those with high overall road avoidance tend to respond in opposite ways when the sensitivity to the four road effects is varied. The same is true of populations with high road surface avoidance when compared to those with high car and high noise avoidance. The model further predicted that traffic volume has a larger effect than road size on the impact of roads on population persistence. One potential application of our model (to run the model on the web or to download it go to www.glel.carieton.ca/ or www.nls.ethz.ch/roadmodel/index.htm or contact the first author) is to generate predictions for more structured field studies of road avoidance behavior and its influence on persistence of wildlife populations. (c) 2005 Elsevier B.V. All rights reserved.

Species respond to habitat at different spatial scales, yet many studies have considered this response only at relatively small scales. We developed a technique and accompanying software (Focus) that use a focal patch approach to select multiple sets of spatially independent sites. For each independent set, regressions are conducted between the habitat variable and counts of species abundance at different scales to determine the spatial scale at which species respond most strongly to an environmental or habitat variable of interest. We applied the technique to determine the spatial scales at which 12 different species of cerambycid beetles respond to forest cover. The beetles responded at different scales, from 20 to 2000 meters. We expect this technique and the accompanying software to be useful for a wide range of studies, including the analysis of existing data sets to answer questions related to the large-scale response of organisms to their environment.

We compared the minnow assemblages of Adirondack lakes with top piscivores with those of lakes having similar physiochemical and biotic characteristics but no top piscivores using a subset of data collected from 1984 to 87 by the Adirondack Lake Survey Corporation. Native minnow richness in lakes with top piscivores was about one third that of lakes without piscivores, with piscivore assemblages dominated by introduced species such as northern pike (Esox lucius), largemouth bass (Micropterus salmoides), and smallmouth bass (Micropterus dolomieu). There was strong evidence that at least four minnow species, including creek chub (Semotilus atromaculatus), northern redbelly dace (Phoxinus eos), blacknose dace (Rhinichthys atratulus), and common shiner (Luxilus cornutus), were less likely to occur in lakes with piscivores; for a fifth species (pearl dace (Margariscus margarita)), the evidence is suggestive but not as strong. Of 13 minnow species, only for two nonnative species (bluntnose minnow (Pimephales notatus) and golden shiner (Notemigonus crysoleucas)) was there strong evidence that their occurrence was unaffected by the presence of introduced piscivores. These results add to the growing body of evidence that the introduction of top piscivores to small temperate lakes puts native minnow communities at high extinction risk.