Genotypes

The file contains genotypes of black bears (Ursus americanus) and coyotes (Canis latrans) detected at caribou calf kill sites in Newfoundland, Canada

Data from: Enhanced understanding of predator–prey relationships using molecular methods to identify predator species, individual and sex

Predator species identification is an important step in understanding predator-prey interactions, but predator identifications using kill site observations are often unreliable. We used molecular tools to analyse predator saliva, scat and hair from caribou calf kills in Newfoundland, Canada to identify the predator species, individual and sex. We sampled DNA from 32 carcasses using cotton swabs to collect predator saliva. We used fragment length analysis and sequencing of mitochondrial DNA to distinguish between coyote, black bear, Canada lynx and red fox and used nuclear DNA microsatellite analysis to identify individuals. We compared predator species detected using molecular tools to those assigned via field observations at each kill. We identified a predator species at 94% of carcasses using molecular methods, while observational methods assigned a predator species to 62.5% of kills. Molecular methods attributed 66.7% of kills to coyote and 33.3% to black bear, while observations assigned 40%, 45%, 10% and 5% to coyote, bear, lynx and fox, respectively. Individual identification was successful at 70% of kills where a predator species was identified. Only one individual was identified at each kill, but some individuals were found at multiple kills. Predator sex was predominantly male. We demonstrate the first large-scale evaluation of predator species, individual and sex identification using molecular techniques to extract DNA from swabs of wild prey carcasses. Our results indicate that kill site swabs (i) can be highly successful in identifying the predator species and individual responsible; and (ii) serve to inform and complement traditional methods

Genotypes

The file contains genotypes of black bears (Ursus americanus) and coyotes (Canis latrans) detected at caribou calf kill sites in Newfoundland, Canada

Data from: Intrinsic traits of woodland caribou Rangifer tarandus caribou calves depredated by black bears Ursus americanus and coyotes Canis latrans

Individuals in substandard physical condition are predicted to be more vulnerable to predation. Support for this prediction is inconsistent partly as a result of differences across systems in the life histories of predator and prey species. Our objective was to examine the physical condition of woodland caribou (Rangifer tarandus caribou) calves depredated by two predators with different life histories in Newfoundland, Canada. Black bears (Ursus americanus) are capable of chasing calves at high speeds over short distances and primarily prey on calves <1 month of age. Coyotes (Canis latrans) are cursorial predators that pursue prey over longer distances, which is expected to result in the selection of substandard individuals. We hypothesized that (i) black bears will kill calves in substandard physical condition, while (ii) coyotes will kill calves from across the distribution of individual conditions. We used mitochondrial DNA species identification tests to assign predator species to calf mortalities. We then used molecular identifications and field observations to build a predictive model using generalized boosted trees to predict the predator species where a molecular identification was unavailable. We tested our hypotheses using Cox proportional hazards models under a competing risks framework. Bears killed younger calves and lighter calves, while coyotes killed heavier calves. Coyotes also killed more late-born calves, which might suggest prey switching as calves become more abundant later in the season. Our findings suggest that the physical constraints of predators play a greater role than predator hunting strategies in this system, but other processes are likely influential. The tendency for coyotes to kill heavier calves might result from sustained coyote predation over time, following the removal by black bears of lighter calves during their first month of age. This research illuminates the complexity of predator-prey interactions in Newfoundland and highlights an important source of variability for predator-prey systems

Cox Regression Model Data

Data from collared caribou calves used in a Cox proportional hazards model to identify differences in the intrinsic traits of calves killed by black bears versus coyotes

Predictive Model Data

Observation data collected from caribou calf mortality locations used in a generalized boosted tree model to predict the predator species

Data from: Intrinsic traits of woodland caribou Rangifer tarandus caribou calves depredated by black bears Ursus americanus and coyotes Canis latrans

Individuals in substandard physical condition are predicted to be more vulnerable to predation. Support for this prediction is inconsistent partly as a result of differences across systems in the life histories of predator and prey species. Our objective was to examine the physical condition of woodland caribou (Rangifer tarandus caribou) calves depredated by two predators with different life histories in Newfoundland, Canada. Black bears (Ursus americanus) are capable of chasing calves at high speeds over short distances and primarily prey on calves <1 month of age. Coyotes (Canis latrans) are cursorial predators that pursue prey over longer distances, which is expected to result in the selection of substandard individuals. We hypothesized that (i) black bears will kill calves in substandard physical condition, while (ii) coyotes will kill calves from across the distribution of individual conditions. We used mitochondrial DNA species identification tests to assign predator species to calf mortalities. We then used molecular identifications and field observations to build a predictive model using generalized boosted trees to predict the predator species where a molecular identification was unavailable. We tested our hypotheses using Cox proportional hazards models under a competing risks framework. Bears killed younger calves and lighter calves, while coyotes killed heavier calves. Coyotes also killed more late-born calves, which might suggest prey switching as calves become more abundant later in the season. Our findings suggest that the physical constraints of predators play a greater role than predator hunting strategies in this system, but other processes are likely influential. The tendency for coyotes to kill heavier calves might result from sustained coyote predation over time, following the removal by black bears of lighter calves during their first month of age. This research illuminates the complexity of predator-prey interactions in Newfoundland and highlights an important source of variability for predator-prey systems

From Adherence to Self-Determination: Evolution of a Treatment Paradigm for People with Serious Mental Illnesses

Treatment adherence and nonadherence is the current paradigm for understanding why people with serious mental illnesses have low rates of participation in many evidence-based practices. The authors propose the concept of self-determination as an evolution in this explanatory paradigm. A review of the research literature led them to the conclusion that notions of adherence are significantly limited, promoting a value-based perspective suggesting people who do not opt for prescribed treatments are somehow flawed or otherwise symptomatic. Consistent with a trend in public health and health psychology, ideas of decisions and behavior related to health and wellness are promoted. Self-determination frames these decisions as choices and is described herein via the evolution of ideas from resistance and compliance to collaboration and engagement. Developments in recovery and hope-based mental health systems have shepherded interest in self-determination. Two ways to promote self-determination are proffered: aiding the rational actor through approaches such as shared decision making and addressing environmental forces that are barriers to choice. Although significant progress has been made toward self-determination, important hurdles remain. (Psychiatric Services 63:169–173, 2012; doi: 10.1176/appi.ps.201100065) Many people with serious mental illnesses do not seem to adhere to treatments as prescribed. In this Open Forum we propose that the concepts of self-determination and choice make greater sense of this phenomenon than the concept of treatment adherence and nonadherence. In 1990, one of us (PWC) coauthored an article published in this journal titled “From Noncompliance to Collaboration in the Treatment of Schizophrenia” (1). The article noted that many people with serious mental illnesses did not benefit from recommended practices, in part because they did not fully participate in them. The 1990 article sought to expand on outdated notions of resistance and compliance by framing treatment decisions about evidence-based practices as a collaborative partnership. Although the model described in the 1990 article was a substantial improvement over ideas of the time, it was nevertheless limited, and further shifts in conceptualizing this phenomenon were required. To support such shifts, we formed the Center on Adherence and Self-Determination (www.casd1.org), which is funded by the National Institute of Mental Health. The first five authors of this paper are co-principal investigators of the center. Self-determination is the crux of the new model, and choice is at the heart of self-determination. We begin this Open Forum by briefly recapping what research has shown—that many people with serious mental illnesses do not fully benefit from available evidence-based care. To make sense of this shortfall, we then consider the evolution of ideas in psychiatric practice, from resistance through collaboration to self-determination. The evolution paralleled a significant change in the mental health system, with themes of recovery, hope, and empowerment becoming more salient. The evolution also informs strategies for helping people decide which services will benefit them, and this Open Forum ends by describing decision-making processes

Data from: Spatiotemporal heterogeneity in prey abundance and vulnerability shapes the foraging tactics of an omnivore

1. Prey abundance and prey vulnerability vary across space and time, but we know little about how they mediate predator-prey interactions and predator foraging tactics. To evaluate the interplay between prey abundance, prey vulnerability, and predator space use, we examined patterns of black bear (Ursus americanus) predation of caribou (Rangifer tarandus) neonates in Newfoundland, Canada using data from 317 collared individuals (9 bears, 34 adult female caribou, 274 caribou calves). 2. During the caribou calving season, we predicted that landscape features would influence calf vulnerability to bear predation, and that bears would actively hunt calves by selecting areas associated with increased calf vulnerability. Further, we hypothesized that bears would dynamically adjust their foraging tactics in response to spatiotemporal changes in calf abundance and vulnerability (collectively, calf availability). Accordingly, we expected bears to actively hunt calves when they were most abundant and vulnerable, but switch to foraging on other resources as calf availability declined. 3. As predicted, landscape heterogeneity influenced risk of mortality, and bears displayed the strongest selection for areas where they were most likely to kill calves, which suggested they were actively hunting caribou. Initially, the per-capita rate at which bears killed calves followed a type-I functional response, but as the calving season progressed and calf vulnerability declined, kill rates dissociated from calf abundance. In support of our hypothesis, bears adjusted their foraging tactics when they were less efficient at catching calves, highlighting the influence that predation phenology may have on predator space use. Contrary to our expectations, however, bears appeared to continue to hunt caribou as calf availability declined, but switched from a tactic of selecting areas of increased calf vulnerability to a tactic that maximized encounter rates with calves. 4. Our results reveal that generalist predators can dynamically adjust their foraging tactics over short time scales in response to changing prey abundance and vulnerability. Further, they demonstrate the utility of integrating temporal dynamics of prey availability into investigations of predator-prey interactions, and move towards a mechanistic understanding of the dynamic foraging tactics of a large omnivore