Timothy Van Deelen - Academia.edu (original) (raw)

Papers by Timothy Van Deelen

Ecological Applications, 2021

Biological data collection is entering a new era. Community science, satellite remote sensing (SR... more Biological data collection is entering a new era. Community science, satellite remote sensing (SRS), and local forms of remote sensing (e.g., camera traps and acoustic recordings) have enabled biological data to be collected at unprecedented spatial and temporal scales and resolution. There is growing interest in developing observation networks to collect and synthesize data to improve broad‐scale ecological monitoring, but no examples of such networks have emerged to inform decision‐making by agencies. Here, we present the implementation of one such jurisdictional observation network (JON), Snapshot Wisconsin, which links synoptic environmental data derived from SRS to biodiversity observations collected continuously from a trail camera network to support management decision‐making. We use several examples to illustrate that Snapshot Wisconsin improves the spatial, temporal, and biological resolution and extent of information available to support management, filling gaps associated...

Canadian Journal of Zoology, 2019

Anti-predator responses to perceived predation risk can influence population demography. Understa... more Anti-predator responses to perceived predation risk can influence population demography. Understanding the relative effect of predator exposure and intraspecific interactions across a variety of anti-predator behaviors provides important insight into inter- and intra-specific drivers of species-specific behaviors. We merged classical behavioral observation methods with camera trapping techniques to examine anti-predator behaviors of white-tailed deer (Odocoileus virginianus (Zimmermann, 1780)) relative to variation in predator exposure and interspecific interactions. We coded 772 behavioral observations from >180 000 images spanning 605 trap-nights. Seasonal differences in behavioral responses to diminishing returns on foraging effort indicated that deer are risk-averse foragers and are more likely to exhibit risky behaviors in the presence of a concentrated food resource when the nutritional value of food resources are high. However, deer tended to spend less time at a site as r...

Ecology and Evolution, 2020

Canadian Journal of Zoology, 2013

We examined predation habits of cougars (Puma concolor (L., 1771)) following the recent recovery ... more We examined predation habits of cougars (Puma concolor (L., 1771)) following the recent recovery of gray wolves (Canis lupus L., 1758) in the southern Greater Yellowstone Ecosystem. With the extirpation of wolves in the early 20th century, cougars likely expanded their niche space to include space vacated by wolves, and increased use of habitat better suited to the foraging of a coursing predator, like wolves. We predicted that as wolves recolonized their former range, competitive exclusion would compel cougars to cede portions of niche space occupied in the absence of wolves. To examine this hypothesis, we radio-tracked cougars and examined their predation sites from winter 2000–2001 through summer 2009. Variation in foraging by cougars was associated with increasing wolf presence. As wolf numbers increased and the mean distance between wolf pack activity centers and cougar predation sites decreased, cougars made kills at higher elevations on more north-facing slopes during summer ...

Illinois Natural History Survey …, 1999

<p>The thick black line delineates the state boundaries and thick red lines delineate study... more <p>The thick black line delineates the state boundaries and thick red lines delineate study area (e.g., northern forest, eastern farmland) boundaries (Created by A. Norton using ArcMap 9.2. Forestland: Wisconsin Department of Natural resources 1998 WISCLAND land cover, Madison WI. County Outlines: U.S. Census Bureau. 1999 Wisconsin County Outlines, Madison, WI).</p

☯ These authors contributed equally to this work. ‡ These authors also contributed equally to thi... more ☯ These authors contributed equally to this work. ‡ These authors also contributed equally to this work.

A New Era for Wolves and People

Wisconsin is world-renowned for its diversity of ecological landscapes and wildlife. As climatic ... more Wisconsin is world-renowned for its diversity of ecological landscapes and wildlife. As climatic fluctuations intensify, the distribution and abundance of these landscapes and associated wildlife populations will be altered. In the following report, we summarize the main issues regarding climate change impacts and adaptation as these relate to Wisconsin’s wildlife. In the first part, we provide a general review of Wisconsin’s climate and ecosystems, outlining trends in recent and anticipated climate change. The second part provides an overview, based on peer-reviewed research and technical publications, of direct and indirect impacts of climate change on wildlife in Wisconsin. Parts three through five illustrate the impacts of climate change using case studies from three major habitat types in the state (forests, wetlands, and grasslands). This discussion serves to highlight impacts that we anticipate across an array of species. Finally, the last part includes a review of adaptation...

Biological Conservation, 2021

Abstract Wildlife managers need reliable information on species distributions (i.e. patterns of o... more Abstract Wildlife managers need reliable information on species distributions (i.e. patterns of occurrence and abundance) to make effective decisions. Historically, managers have relied on harvest records (collected at broad spatial extents but coarse resolution) to monitor wildlife populations. However, emerging citizen-science datastreams can potentially supplement harvest-based monitoring by providing fine-resolution data that permit identification of species-environment relationships needed to predict occurrence and abundance. We combined harvest records and citizen-science camera-trap data in integrated species distribution models (iSDMs) to estimate species-environment relationships and distribution patterns of six wildlife species in Wisconsin, USA. We expected that iSDMs would more precisely estimate species-environment relationships and predict spatial abundance patterns intermediate between camera- and harvest-only SDMs. We also conducted simulations to explore the consequences of incomplete knowledge of harvest effort for estimates of abundance and species-environment relationships. Integrated models produced more precise species-environment relationships than camera-only models in 53% of the relationships we tested; all harvest-only models failed to converge. Moreover, integrated and camera-only models showed low agreement (mean: 19.67%) in identifying abundance “hotspots” but considerably higher agreement (mean: 45.17%) in identifying abundance “cold spots”. Our simulations showed that abundance patterns estimated by iSDMs may suffer from imprecision if harvest effort is poorly measured. We recommend that harvest records be collected at finer spatial resolutions and be paired with in-depth effort reporting. Our work demonstrates the potential for integrating an existing datastream (harvest records) with an emerging one (citizen-science camera-trap monitoring) for modeling species distributions and providing support for wildlife management decisions.

Mammalia, 2019

Selective pressures (i.e. resource limitation and competitive interaction) that drive the composi... more Selective pressures (i.e. resource limitation and competitive interaction) that drive the composition of ecological communities vary, and often operate on different ecological scales (ecological variables across varying spatial scales) than observed patterns. We studied the drivers of distribution and abundance of the American marten (Martes americana) and the carnivore community at three ecological scales on a Great Lakes island archipelago using camera traps. We found different drivers appeared important at each ecological scale and studying any of the three scales alone would give a biased understanding of the process driving the system. Island biogeography (resource limitation) was most important for carnivore richness, with higher richness on larger islands and lower richness as distance from the mainland increased. Marten presence on individual islands appeared to be driven by island size (resource limitation) and human avoidance (competitive interaction). Marten abundance at ...

Scientific reports, Jan 20, 2018

Population estimation is essential for the conservation and management of fish and wildlife, but ... more Population estimation is essential for the conservation and management of fish and wildlife, but accurate estimates are often difficult or expensive to obtain for cryptic species across large geographical scales. Accurate statistical models with manageable financial costs and field efforts are needed for hunted populations and using age-at-harvest data may be the most practical foundation for these models. Several rigorous statistical approaches that use age-at-harvest and other data to accurately estimate populations have recently been developed, but these are often dependent on (a) accurate prior knowledge about demographic parameters of the population, (b) auxiliary data, and (c) initial population size. We developed a two-stage state-space Bayesian model for a black bear (Ursus americanus) population with age-at-harvest data, but little demographic data and no auxiliary data available, to create a statewide population estimate and test the sensitivity of the model to bias in the...

Ecology and evolution, 2018

Implicit and explicit use of expert knowledge to inform ecological analyses is becoming increasin... more Implicit and explicit use of expert knowledge to inform ecological analyses is becoming increasingly common because it often represents the sole source of information in many circumstances. Thus, there is a need to develop statistical methods that explicitly incorporate expert knowledge, and can successfully leverage this information while properly accounting for associated uncertainty during analysis. Studies of cause-specific mortality provide an example of implicit use of expert knowledge when causes-of-death are uncertain and assigned based on the observer's knowledge of the most likely cause. To explicitly incorporate this use of expert knowledge and the associated uncertainty, we developed a statistical model for estimating cause-specific mortality using a data augmentation approach within a Bayesian hierarchical framework. Specifically, for each mortality event, we elicited the observer's belief of cause-of-death by having them specify the probability that the death w...

The Canadian Field-Naturalist, 2007

Published reports of peak breeding and parturition dates for White-tailed Deer (Odocoileus virgin... more Published reports of peak breeding and parturition dates for White-tailed Deer (Odocoileus virginianus) indicate that deer in northern regions typically breed during November and give birth during late May and early June. However, we report a late-born White-tailed Deer fawn killed by a vehicle between 12-13 March 2007 in south central Wisconsin. Morphology measurements and body weight indicated the individual was 63-76 days old, was born between 26 December 2006 and 8 January 2007, and was conceived between 14-27 June 2006. To our knowledge, this observation represents the latest documented breeding activity in northern deer populations.

Wildlife Society Bulletin, 2015

Background/Question/Methods Information on unobservable population processes (discrepancies) can ... more Background/Question/Methods Information on unobservable population processes (discrepancies) can contribute to fuller understanding of observed patterns and processes whereas implications of failing to include unobservable population processes lead to a misunderstanding of population dynamics and, potentially, to ineffective management. However, few flexible, rigorous models are available to accurately estimate discrepancies in population growth. A promising method for estimating unobserved population processes is through integrated population models (IPMs) where multiple data sources with shared parameters are used in a common model. Our goal was to improve on the IPM framework to help conservationists, managers, and researchers make more informed decisions about conservation and management of populations through estimation of discrepancies in the growth process. In this paper, we 1) introduce a flexible, general IPM and method to estimate unknown population processes with commonly...

PloS one, 2015

White-tailed deer (Odocoileus virginianus) are commonly exposed to disease agents that affect liv... more White-tailed deer (Odocoileus virginianus) are commonly exposed to disease agents that affect livestock but environmental factors that predispose deer to exposure are unknown for many pathogens. We trapped deer during winter months on two study areas (Northern Forest and Eastern Farmland) in Wisconsin from 2010 to 2013. Deer were tested for exposure to six serovars of Leptospira interrogans (grippotyphosa, icterohaemorrhagiae, canicola, bratislava, pomona, and hardjo), bovine viral diarrhea virus (BVDV-1 and BVDV-2), infectious bovine rhinotracheitis virus (IBR), and parainfluenza 3 virus (PI3). We used logistic regression to model potential intrinsic (e.g., age, sex) and extrinsic (e.g., land type, study site, year, exposure to multiple pathogens) variables we considered biologically meaningful to exposure of deer to livestock pathogens. Deer sampled in 2010-2011 did not demonstrate exposure to BVDV, so we did not test for BVDV in subsequent years. Deer had evidence of exposure to ...

Recovery of Gray Wolves in the Great Lakes Region of the United States, 2009