Erica J. Newton

Ministry of Natural Resources and Forestry

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Bruce A. Pond

Ministry of Natural Resources and Forestry

Erin L. Koen

Cherokee Nation

Martyn E. Obbard

Ministry of Natural Resources and Forestry

Kevin R. Middel

Ministry of Natural Resources and Forestry

Brent R. Patterson

Ministry of Natural Resources and Forestry

Jeff Clune

University of British Columbia

James A. Schaefer

Trent University

Kurt C. VerCauteren

Animal and Plant Health Inspection Service

Reesa Y. Conrey

Colorado Parks and Wildlife

Justin T. Ridge

Marine Conservation Institute

Cooperative Institutions

Ministry of Natural Resources and Forestry

Trent University

Centre National de la Recherche Scientifique

Université de Montpellier

Colorado State University

University of Guelph

Centre d'Écologie Fonctionnelle et Évolutive

Wuhan University

Duke University

Institut de Recherche pour le Développement

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Trends in body condition in polar bears (Ursus maritimus) from the Southern Hudson Bay subpopulation in relation to changes in sea ice

Arctic Science (2016)

Martyn E. Obbard Marc Cattet Eric J. Howe Kevin R. Middel Erica J. Newton

Sea ice is declining over much of the Arctic. In Hudson Bay the ice melts completely each summer, and advances in break-up have resulted in longer ice-free seasons. Consequently, earlier break-up is implicated in declines in body condition, survival, and abundance of polar bears (Ursus maritimus Phipps, 1774) in the Western Hudson Bay (WH) subpopulation. We hypothesised that similar patterns would be evident in the neighbouring Southern Hudson Bay (SH) subpopulation. We examined trends 1980–2012 in break-up and freeze-up dates within the entire SH management unit and within smaller coastal break-up and freeze-up zones. We examined trends in body condition for 900 bears captured during 1984–1986, 2000–2005, and 2007–2009 and hypothesised that body condition would be correlated with duration of sea ice. The ice-free season in SH increased by about 30 days from 1980 to 2012. Body condition declined in all age and sex classes, but the decline was less for cubs than for other social classes. If trends towards a longer ice-free season continue in the future, further declines in body condition and survival rates are likely, and ultimately declines in abundance will occur in the SH subpopulation.

Ursus maritimus

10.1139/as-2015-0027

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Citations (109)

Advancing UAS methods for monitoring coastal environments

AGU Fall Meeting Abstracts (2017)

Justin T. Ridge Alexander C. Seymour Antonio B. Rodriguez Julian Dale Erica J. Newton

Source

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Citations (1)

Causes and Consequences of Broad-Scale Changes in the Distribution of Migratory Caribou (<i>Rangifer tarandus</i>) of Southern Hudson Bay

ARCTIC (2015)

Erica J. Newton Kenneth F. Abraham James A. Schaefer Bruce A. Pond Glen S. Brown

Understanding the factors driving changes in species distributions is fundamental to conservation, but for wide-ranging species this is often complicated by the need for broad-scale observations across space and time. In the last three decades, the location of summer concentrations of migratory caribou (Rangifer tarandus) in southern Hudson Bay (SHB), Canada, has shifted south and east as much as 500 km. We used long-term data (1987 – 2011) to test two hypotheses that could explain the distribution shift: forage depletion and anthropogenic disturbance. Over time and space, we compared the body size of live-captured adult female caribou, dietary quality from fecal nitrogen in July, the location of VHF- and GPS-collared female caribou in July, distribution of all-terrain vehicle (ATV) tracks and caribou tracks in August, and the proximity of collared caribou to sections of the coast with higher ATV activity in spring and summer. The forage depletion hypothesis was supported by greater body size and dietary quality in caribou of the eastern portion of SHB than in western SHB animals in 2009 – 11. The anthropogenic disturbance hypothesis was supported by the negative correlation of the distributions of ATV tracks and caribou tracks on the coast in 2010 and the fact that caribou avoided areas with ATV activity by 10 – 14 km. In 1987, collared caribou were observed largely along the coast in western SHB in mid-July, while in 2009 – 11, they were inland in western SHB and along the coast in eastern SHB. While these locations demonstrate a substantial change in summer distribution over three decades, we were unable to differentiate between forage depletion and anthropogenic disturbance as a single causal factor of the distribution shift.

10.14430/arctic4524

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Citations (8)

Improving the accessibility and transferability of machine learning algorithms for identification of animals in camera trap images: MLWIC2

bioRxiv (Cold Spring Harbor Laboratory) (2020)

Michael A. Tabak Mohammad Sadegh Norouzzadeh David W. Wolfson Erica J. Newton Raoul K. Boughton

Abstract Motion-activated wildlife cameras (or “camera traps”) are frequently used to remotely and non-invasively observe animals. The vast number of images collected from camera trap projects have prompted some biologists to employ machine learning algorithms to automatically recognize species in these images, or at least filter-out images that do not contain animals. These approaches are often limited by model transferability, as a model trained to recognize species from one location might not work as well for the same species in different locations. Furthermore, these methods often require advanced computational skills, making them inaccessible to many biologists. We used 3 million camera trap images from 18 studies in 10 states across the United States of America to train two deep neural networks, one that recognizes 58 species, the “species model,” and one that determines if an image is empty or if it contains an animal, the “empty-animal model.” Our species model and empty-animal model had accuracies of 96.8% and 97.3%, respectively. Furthermore, the models performed well on some out-of-sample datasets, as the species model had 91% accuracy on species from Canada (accuracy range 36-91% across all out-of-sample datasets) and the empty-animal model achieved an accuracy of 91-94% on out-of-sample datasets from different continents. Our software addresses some of the limitations of using machine learning to classify images from camera traps. By including many species from several locations, our species model is potentially applicable to many camera trap studies in North America. We also found that our empty-animal model can facilitate removal of images without animals globally. We provide the trained models in an R package ( mlwic 2: Machine Learning for Wildlife Image Classification in R), which contains Shiny Applications that allow scientists with minimal programming experience to use trained models and train new models in six neural network architectures with varying depths.

Transferability

Trap (plumbing)

Identification

Camera trap

10.1101/2020.03.18.997700

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Citations (11)

Too many to count: Using orthophotography to census an unharvested beaver (Castor canadensis) population in Ontario

Ecosphere (2022)

Ashley McLaren Erica J. Newton A. Silver Mike Allan Kevin R. Middel

Abstract Various methods exist to monitor wildlife populations and estimate trends in their distribution and abundance. For American beaver ( Castor canadensis ), aerial surveys provide a means to obtain abundance data over large areas and typically involve observers searching watercourses and shorelines for active beaver presence. Here, we describe a systematic aerial photographic census we designed and executed in autumn to quantify annual beaver colony abundance on the 184‐km 2 Michipicoten Island, Ontario, from 2015 to 2019. Aerial photographs were stitched together into orthophotomosaics after each census and visually searched for beaver food caches, with each food cache representing an independent beaver colony. Our methods revealed that beaver colony abundance declined substantially from a peak of 6.1 colonies/km 2 in 2015, the highest reported across North America, to 0.4 colonies/km 2 in 2018. Beaver abundance remained low through 2019. Although photographing the entire isolated study area required relatively little time and effort, even when beaver density was very high, post‐census processing work was time‐consuming. Lessons learned will improve efficiencies of our future censuses and aid other researchers. Our method is advantageous over traditional aerial wildlife surveys in that it provides a digital and visual record that can be used for additional analyses.

Castor canadensis

Aerial Survey

10.1002/ecs2.4185

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Citations (4)

Evaluating potential sources of invasive wild pigs in Ontario

Ecology and Evolution (2021)

Erin L. Koen Erica J. Newton E. Hance Ellington

Invasive wild pigs (Sus scrofa) are considered one of the most damaging species globally, and once they become established in an area, they are notoriously difficult to eliminate. As such, identifying the potential pathways of invasion, especially in places with emerging populations, is critical for preventing new or continued invasion. Wild pigs have been reported in Ontario, Canada, in recent years. We tested four nonexclusive hypotheses about the source of wild pigs in Ontario: (a) escapees from captive sources within Ontario; (b) invasion from neighboring jurisdictions; (c) existing wild populations within Ontario; and (d) translocation and illegal release. We found that sightings of Eurasian wild boar were closer to premises with wild boar than were random locations; wild boar sightings were an average of 16.3 km (SD = 25.4 km, min = 0.2 km, n = 20) from premises with wild boar. We also found that sightings of domestic pigs were closer to domestic pig farms than expected. Sightings of wild pigs in groups of more than four animals were rare. Our results suggest that wild pigs observed in Ontario are recent escapes from captivity, recognizing that there may be established groups of wild pigs that we have not yet detected. While not common, we also received reports indicating that in the past, wild pigs have been translocated and illegally released. Other North American jurisdictions that have been successful at eliminating wild pigs have removed existing populations and changed regulations to limit future invasion, such as prohibiting possession and transport of wild boar and prohibiting hunting of wild pigs.

Wild boar

Domestic pig

Captivity

10.1002/ece3.8160

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Citations (7)

Permanent Genetic Resources added to Molecular Ecology Resources Database 1 December 2011 – 31 January 2012

Molecular Ecology Resources (2012)

Maria Cristina Arias Emilie Arnoux James J. Bell Abel Bernadou GIORGIA BINO

Abstract This article documents the addition of 473 microsatellite marker loci and 71 pairs of single‐nucleotide polymorphism (SNP) sequencing primers to the Molecular Ecology Resources Database. Loci were developed for the following species: Barteria fistulosa, Bombus morio, Galaxias platei, Hematodinium perezi, Macrocentrus cingulum Brischke (a.k.a. M. abdominalis Fab., M. grandii Goidanich or M. gifuensis Ashmead) , Micropogonias furnieri, Nerita melanotragus, Nilaparvata lugens Stål , Sciaenops ocellatus, Scomber scombrus, Spodoptera frugiperda and Turdus lherminieri . These loci were cross‐tested on the following species: Barteria dewevrei , Barteria nigritana , Barteria solida , Cynoscion acoupa, Cynoscion jamaicensis, Cynoscion leiarchus, Cynoscion nebulosus, Cynoscion striatus, Cynoscion virescens, Macrodon ancylodon, Menticirrhus americanus, Nilaparvata muiri and Umbrina canosai . This article also documents the addition of 116 sequencing primer pairs for Dicentrarchus labrax.

Sciaenidae

10.1111/j.1755-0998.2012.03133.x

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Citations (24)

Remote sensing reveals long-term effects of caribou on tundra vegetation

Polar Biology (2014)

Erica J. Newton Bruce A. Pond Glen S. Brown Kenneth F. Abraham James A. Schaefer

Ungulate

Circumpolar star

10.1007/s00300-014-1472-3

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Citations (21)

Experimental test of the efficacy of hunting for controlling human–wildlife conflict

Journal of Wildlife Management (2023)

Joseph M. Northrup Eric J. Howe Jeremy Inglis Erica J. Newton Martyn E. Obbard

Abstract Human–wildlife conflict can cause major declines in wildlife populations and pose a threat to human safety and livelihoods. Large carnivores are among the most conflict‐prone species because they range widely, eat human‐associated foods, and can pose a risk to human safety. Legal harvest of carnivores by licensed hunters is an attractive method to attempt to reduce conflict; however, there is mixed evidence for its effectiveness. We leveraged a unique management project in Ontario, Canada in which a new spring American black bear ( Ursus americanus ) hunting season was implemented in selected wildlife management units in addition to the existing fall season. We examined human–bear interactions and incidents before (2012 and 2013) and after (2014 and 2015) this implementation in treatment and control areas. Further, using data from 2004–2019, we examined the longer‐term patterns of human–bear interactions and incidents before and after this management project when a spring season was implemented throughout the entire province beginning in 2016. Harvest increased significantly upon the implementation of the spring season in selected units, but there was no concomitant reduction in interactions or incidents, and these were higher in areas with the new spring season relative to control areas. Human–bear interactions, incidents, and harvest were strongly related to the availability of natural foods in all analyses. Regulated, presumably sustainable harvest was ineffective at reducing human–bear interactions and incidents in the near‐term and might have increased both. Our results support a long history of research showing that natural food availability is a primary driver of human–wildlife conflict. Programs promoting coexistence between people and wildlife, including education, capacity building, and management of unnatural food sources are likely to be the most successful at reducing conflicts between people and bears.

Human–wildlife conflict

Hunting season

10.1002/jwmg.22363

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Citations (6)

Predicting high-risk areas for African swine fever spread at the wild-domestic pig interface in Ontario

Preventive Veterinary Medicine (2021)

Lisa Pollock Erica J. Newton Erin L. Koen

Domestic pig

10.1016/j.prevetmed.2021.105341

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Citations (7)