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Coyote (Canis latrans) presence in many North American cities evokes fear in some humans, driving demands for management action. With societal values shifting towards non-lethal coexistence practices, many wildlife managers turn to strategies like aversion conditioning, designed to increase coyotes' fear of humans. Yet, scant knowledge exists about baseline fear behaviors (e.g., vigilance, alertness) in urban coyotes. This has implications for coexistence practices, as the motivation for coyotes' behavior should underscore how managers respond. To explore urbanization effects on fear and behavior, we used remote cameras to monitor three coyote families during the pup-rearing season in urban, peri-urban, and rural sites in/near Calgary, Canada (2021-2022). We coded behaviors observed in adults and pups using 62 822 images. Rural adult coyotes were observed more around pups, while urban and peri-urban coyotes were observed more around pups that were playing, spent more time den-guarding, and showed higher alertness. This adaptive response in urban and peri-urban coyotes may force some coyotes into a behavioral trade-off (e.g., guarding pups vs. foraging), which could translate into more risky behaviors (e.g., consuming garbage). The elevated baseline fear in coyotes facing urban pressures suggests that coexistence practitioners must consider the risks of increasing fear during aversion conditioning.

Compare liver copper (Cu) concentration, as a metric of dietary Cu exposure, in senior dogs euthanized for geriatric health concerns against free-foraging coyotes. Liver samples (April 7, 2023, to April 22, 2024) from 104 dogs and 88 coyotes were histologically evaluated, assigned rhodanine Cu scores, and had liver Cu quantified (µg/g of dry weight liver [dwl]). Medical records, signalment, and dietary history were acquired for dogs. Water Cu from relevant geolocations was analyzed. Dietary Cu (manufacturer typical analyses or inductively coupled plasma atomic emission spectroscopy [USDA micronutrient laboratory]) was normalized as mg of Cu/100 kcal (metabolizable energy was calculated with modified Atwater factorials). Dietary Cu intake was categorized as Cu-restricted (0.15 to 0.24 mg of Cu/100 kcal) or Cu-replete (0.31 to 0.39 and ≥ 0.40 mg of Cu/100 kcal). Nonparametric statistics defined significant differences and associations. There were 35 of 104 rhodanine-positive samples (34%) from dogs versus 0 of 88 from coyotes. Median (range; 95% CI) liver Cu concentration (µg/g of dwl) in dogs (248 [70 to 1,795; 267 to 369]) significantly exceeded that in coyotes (25 [5 to 114; 27 to 36]). Liver Cu concentrations of 69 rhodanine-negative dog samples, including 13 dogs fed Cu-restricted diets, also were significantly higher than those of coyotes. Liver Cu was 201 (70 to 370; 182 to 218) µg/g of dwl in all rhodanine-negative dogs and was 190 (79 to 355; 132 to 250) µg/g of dwl in dogs fed Cu-restricted diets. Significantly greater liver Cu concentration in geriatric dogs compared to free-foraging coyotes corroborates concern regarding higher dietary Cu intake in dogs fed commercial dog foods. Findings did not imply, without further investigation, whether lower coyote liver Cu is optimized for canid health and metabolism or merely reflects food-derived Cu intake and interspecies differences. Findings added case-based evidence supporting concern for excessive Cu in commercial dog foods.

Animal decision-making directly impacts survival and reproductive success, particularly for reproductive habitat specialists (e.g., denning species) in highly dynamic environments. Despite the widespread and increasing distribution of coyotes (Canis latrans) in urban areas, little research has focused on how they select urban den sites. In this study, we investigated den structure and site selection of coyotes in Atlanta, Georgia. From January to April of 2022-2024, we GPS collared 48 coyotes and located 20 dens in April of 2022-2025. We measured the physical characteristics of dens and categorized structure type as anthropogenic or natural. We used a 3rd-order resource selection analysis to assess impacts of impervious surface (%), distance to buildings, and distance to cover habitat on den site selection. We found that approximately half of the dens were located in anthropogenic structures, which coyotes appeared to use opportunistically for concealment and protection. We also identified strong selection for cover habitat and avoidance of impervious surfaces by coyotes for den sites. Our findings indicate that coyotes in Atlanta avoid areas with high human infrastructure, select areas with cover, and show flexibility in structure use allowing them to safeguard dens. While this showcases the adaptability of coyotes when making complex reproductive decisions, it also highlights the potential population level impacts increased urbanization and land conversion may have on urban wildlife.

We aimed to confirm the identity of a nematode recovered from the right ventricle of a coyote heart at dissection, using published molecular methods to validate morphological diagnosis of Dirofilaria immitis (dog heartworm). An adult nematode was recovered during dissection of the heart from a coyote (Canis latrans) that was hunted on Prince Edward Island (PEI) in January 2021 and frozen at -20°C before being processed in June 2024. The nematode was identified based on size and morphological features. Species identity was confirmed via PCR and DNA sequencing of the D. immitis specific surface antigen gene. The adult male nematode discovered in the right ventricle of a coyote hunted near Summerville, PEI, was confirmed to be D. immitis, sharing 99% identity with published sequences in GenBank. This finding indicates that D. immitis is established in PEI and could spread to other wild or domestic canids. Dirofilaria immitis can cause severe cardiopulmonary disease in domestic dogs. Veterinarians in the maritime provinces should be mindful of the probability that local dogs without travel history that are presented with cardiopulmonary issues could be infected with D. immitis. Premier cas rapporté de Dirofilaria immitis chez un coyote (Canis latrans) de l’Île-du-Prince-Édouard. Notre objectif était de confirmer l’identité d’un nématode prélevé dans le ventricule droit d’un cœur de coyote lors de sa dissection, en utilisant des méthodes moléculaires publiées pour valider le diagnostic morphologique de Dirofilaria immitis (dirofilariose canine). Un nématode adulte a été obtenu lors de la dissection du cœur d’un coyote (Canis latrans) chassé sur l’Île-du-Prince-Édouard (Î.-P.-É.) en janvier 2021 et congelé à −20 °C avant d’être traité en juin 2024. Le nématode a été identifié en fonction de sa taille et de ses caractéristiques morphologiques. L’espèce a été confirmée par PCR et séquençage d’ADN du gène de l’antigène de surface spécifique de D. immitis. Le nématode mâle adulte découvert dans le ventricule droit d’un coyote chassé près de Summerville (Î.-P.-É.) a été identifié comme étant D. immitis, présentant une identité de 99 % avec les séquences publiées dans GenBank. Cette découverte indique que D. immitis est établi à l’Î.-P.-É. et pourrait se propager à d’autres canidés sauvages ou domestiques. Dirofilaria immitis peut causer une grave maladie cardiopulmonaire chez les chiens domestiques. Les vétérinaires des provinces maritimes doivent être conscients de la possibilité que des chiens locaux n’ayant pas voyagé et présentant des problèmes cardiopulmonaires soient infectés par D. immitis.(Traduit par Dr Serge Messier).

Comparative studies show that urban coyotes behave differently from rural counterparts. However, these studies often homogenize cities. Cities feature diverse pressures for wildlife, such as variation in human densities and environmental health, two factors known to increase risk-taking. This heterogeneity creates a landscape of risk, which may drive locally adapted behavioral strategies within cities. Yet, the influence of these pressures on coyote behavior remains unclear. To investigate this, we conducted novel object testing at 24 sites across gradients of human density and pollution. We recorded coyote detections, group size, and behavioral responses to the novel object, focusing on time spent alert, time spent close, and total exploration. We found that coyote detections varied with human density and pollution, with markedly lower detections in areas with high human density and pollution. Coyote boldness (time spent alert and close) and exploration were uniformly associated with human density, with coyotes in high human density areas displaying elevated boldness and heightened exploration. We also found that time spent close and exploration increase with group size. In contrast, coyote risk-taking did not vary with pollution. Our results suggest that heterogeneity in human density, environmental health, and social context differentially affects coyote ecology, which may have consequences for human-carnivore coexistence.

Understanding species range dynamics is central to ecology and biogeography, particularly as global environmental change accelerates range shifts, expansions, and biological invasions. Carnivores are notable for their capacity to exploit human-modified landscapes, yet most research has focused on temperate regions where apex predator extirpation often facilitates expansion. By contrast, carnivore range expansions in tropical landscapes remain poorly documented. Here we assess the recent southward expansion of coyotes (Canis latrans) into the human-modified tropics of Mesoamerica, where they now overlap with apex predator assemblages. We compiled 278 coyote records from areas lacking previous evidence of their presence by integrating data from 44 camera-trap surveys (1125 cameras deployed, totaling 203,682 camera-trap/days between 2012 and 2025) and citizen-science platforms (iNaturalist and the Global Biodiversity Information Facility). To investigate drivers of coyote occurrence, we fitted a generalized linear model (GLM) using the Global Human Modification Index (GHMI), the Normalized Difference Vegetation Index (NDVI), and spatiotemporal factors as predictors. Model results indicated higher probabilities of coyote occurrence in more human-modified landscapes (higher GHMI) and areas with lower vegetation greenness (lower NDVI). Furthermore, a significant positive temporal trend indicated that the probability of occurrence increased annually. This case highlights how land-use change facilitates range expansions at continental margins and underscores the conceptual blurring between native range expansion and invasion processes. The ability of coyotes to thrive in both natural and human-dominated environments suggests continued spatial expansion, reinforcing the need for proactive management strategies grounded in both ecological science and local sociocultural contexts.

Wild canids serve as definitive hosts for numerous Sarcocystis species infecting livestock and wildlife. However, species-level identification in free-ranging carnivores remains difficult, impeded by the morphological resemblance among the sporocysts of various parasite species. Intestinal mucosal scrapings from 40 wild canids: red fox (Vulpes vulpes, n = 8), gray fox (Urocyon cinereoargenteus, n = 6) and coyote (Canis latrans, n = 26) in Pennsylvania, USA, sampled in 2024, were tested for Sarcocystis sporocysts. Sporocysts were detected microscopically in intestinal homogenates digested in Chlorox in 3/6 (50%) gray foxes, 3/8 (37.5%) red foxes and 18/26 (69.2%) coyotes. PCR amplification was successful on 8/18 (44.4%) coyotes, 0/6 Gy foxes and 2/3 (66.6%) red foxes. Multi-locus genotyping was performed for the 18S rRNA, 28S rRNA, COI and ITS1 genetic markers, supporting identification of multiple species of Sarcocystis, including Sarcocystis albifronsi-like, S. cruzi, S. gjerdei-like, S. cristata/S. wenzeli-like and an additional undescribed, ungulate-associated Sarcocystis spp. Phylogenetic analysis confirmed clustering with reference sequences with strong support. This study demonstrates that wild foxes and coyotes serve as definitive hosts for multiple species of Sarcocystis, including Sarcocystis cruzi, which uses cattle as intermediate hosts and imposes significant economic burdens on cattle production. Moreover, these findings demonstrate that wild canids harbor diverse Sarcocystis spp., supporting their role in environmental dissemination and potential transmission at the wildlife-livestock interface.

Coyotes (Canis latrans) expanded across eastern North America in the last century and are ecological generalists capable of thriving across diverse habitats. Broad genetic surveillance has reported little spatial genetic patterning for this highly dispersive species. Here, we explore the genome-wide signatures of spatial patterns found in a 10-year study of 1199 coyotes from northeastern United States, with a temporal analysis of Pennsylvania coyotes. Despite their broad dispersal capability, we detected subtle but significant population structure, with two genetic clusters that have a weak clinal transition zone. This partitioning aligned qualitatively with patterns of human population density and activity. We inferred that gene flow between these genetic groups was associated with two different demographic expansions of coyotes eastward, south along the Great Lakes and separately along the northern Lakes towards northeastern United States. We identify Pennsylvania as a recent contact zone. Morphometric analyses revealed only modest differentiation between clusters and no robust temporal shifts, though a weak trend of increased body mass was noted in southwestern males. Collectively, our findings demonstrate that anthropogenic features likely influence fine-scale cryptic population structure, even in a highly dispersing and widespread mesopredator.

Coyote (Canis latrans) populations are expanding into urban areas, yet how their feeding ecology adapts to the wildland-urban interface remains poorly understood, particularly near megacities such as Mexico City. We evaluated coyote diet across an anthropogenic gradient in the Sierra del Ajusco, comparing a conserved site (Las Rosas) and a human-modified site (Las Maravillas). We analyzed 198 scats collected over 1 year, using prey diversity (Shannon-Wiener H') and network modularity (Louvain algorithm) to assess spatial and seasonal variation. Mammals dominated the diet at both sites, with Microtus mexicanus as the primary prey. Annual dietary diversity did not differ significantly between the conserved (H' = 2.245) and modified (H' = 2.368) sites (p = 0.2502), consistent with low network modularity (0.073). In contrast, seasonal variation differed between sites: the conserved site showed a significant shift in diet diversity (p = 0.02587), whereas the modified site did not (p = 0.6874). These results indicate that the primary effect of anthropogenic disturbance is not a change in overall diet diversity, but a buffering of seasonal variation. The year-round availability of anthropogenic resources in the modified landscape appears to decouple coyote feeding ecology from natural seasonal cycles, with potential consequences for its ecological role.

Effective antimicrobial resistance (AMR) surveillance and mitigation efforts require locally adapted approaches that consider both ecological and public health dimensions. The coyote (Canis latrans) is widely distributed in Costa Rica, especially in buffer zones between conserved ecosystems and human settlements, and frequently interacts with local communities and domestic animals. In this study, we investigated the potential of C. latrans as a sentinel species for environmental AMR monitoring in Costa Rica. Fecal samples were opportunistically collected from two conservation areas, Guanacaste (ACG) and Central (ACC), between March and August 2022. Species confirmation was achieved through mitochondrial D-loop sequencing. We evaluated the prevalence and spatial distribution of nine antimicrobial resistance genes (ARGs) in microbial DNA extracted from coyote scat deposition. Multidrug-resistant microbiomes were detected in 74% of the samples (26/35). ARG prevalence was higher in regions with greater human population density, with detection rates of 23% in the ACC compared to 13% in the ACG. Analysis of the most frequently detected genes (sulII, tetQ, tetY, and catAI) revealed significant differences in gene abundance and distribution between conservation areas (PERMANOVA, F = 3.944, p = 0.0084). Additionally, host genetic analysis using coyote mtDNA provided the first preliminary insight into population genetics in Costa Rica, revealing low haplotype (n = 3), haplotype diversity (Hd = 0.606), and nucleotide diversity (π = 0.0099). This study contributes baseline data to guide conservation and public health policy in the region, providing valuable information for controlling AMR in Costa Rica.

Spirocerca lupi is a nematode that infects domestic dogs and wild carnivores. This study retrospectively analyzed postmortem records between 1989 and 2024 to assess S. lupi-associated lesions in coyote necropsies. In addition, it conducted molecular characterization of 18S rRNA and cytochrome oxidase subunit 1 (cox1) gene fragments of larvae found at necropsies. Fecal samples from free-ranging coyotes were molecularly examined for S. lupi 18S DNA. Of the 39 coyote cases, 33 (84. 6%) presented S. lupi-associated lesions. A significant association was observed between the presence of Spirocerca nematodes and the development of esophageal granulomas and aortic aneurysms. In addition, an atypical case of spinal cord invasion was documented, representing the first reported occurrence of this condition in coyotes. Out of all fecal samples tested, 4.6% were positive for S. lupi infection. The obtained cox1 sequence revealed a complete similarity to S. lupi isolated from the Andean fox Lycalopex culpaeus from Peru, suggesting its transmission between wild canid populations. These findings indicate that coyotes play a significant role in S. lupi transmission dynamics and highlight the need for further research on the ecological interactions between domestic and wild canids in Costa Rica.

Canine parvovirus type 2 (CPV-2) is a primary etiological agent of acute gastroenteritis in domestic dogs. Although molecular and serological evidence have confirmed its circulation in wild carnivores, the clinical impact of spillover events in wildlife hosts remain insufficiently characterized. In this study, we investigated CPV-2 from wild coyote pups (Canis latrans) presenting with clinical gastroenteritis in northeastern Mexico. CPV-2 was successfully isolated in MDCK cells, and whole-genome sequencing was performed on two isolates, B55 and B56 (GenBank accession numbers PQ065988 and PQ065989). A comprehensive analysis identified 23 nucleotide mutations, eight of which were missense mutations resulting in amino acid substitutions in structural (VP) and non-structural (NS) proteins. Notably, amino acid substitution L354V was identified in the NS1 helicase domain of both isolates, a region critical for viral replication. Phylogenetic analysis confirmed that isolates B55 and B56 cluster within the CPV-2c subtype, showing high genetic relatedness to circulating Mexican and US canine strains which strongly suggests recent cross-species transmission between domestic dogs and wild coyotes. This study provides the first complete genomic characterization of a clinical CPV-2 infection in wild coyotes in Mexico, underscoring the immediate risk of CPV-2c transmission at the domestic animal-wildlife interface.

Echinococcus multilocularis is a zoonotic cestode that uses canids as definitive hosts and rodents as intermediate hosts. In humans, this parasite is the causative agent of alveolar echinococcosis. Recently, its range has been expanding across the Northern Hemisphere, and it is increasingly detected in wild canids, domestic dogs, and humans across Canada and the United States. While this expansion has been documented in isolated studies across the continent, a lack of routine sampling in wildlife hinders our ability to anticipate and mitigate further spread of E. multilocularis. We confirmed the presence of E. multilocularis in Washington State, USA, using a combination of morphological and molecular techniques across carcasses and field-collected scats of coyotes (Canis latrans), this region's most common wild canid. Morphological identification of adult worms was confirmed by next-generation sequencing. Over a third of all samples tested positive for E. multilocularis when all methodologies were combined. Sequencing revealed a haplotype of E. multilocularis matching a documented haplotype originally of European origin in British Columbia, Canada. Our study provides the first confirmation of E. multilocularis in a wild host on the west coast of the contiguous United States and provides additional haplotype information crucial to tracking the geographical expansion of the parasite. We also provide a new next-generation sequencing primer targeting cestodes of canids. The difference in amplification between intestinal and fecal samples suggests that non-invasive fecal sampling using DNA metabarcoding - a popular method of helminth surveillance - may lead to underestimation of prevalence, hindering control measures. The global significance of these findings extends beyond North America; E. multilocularis is a major public health concern in Europe and Asia, where alveolar echinococcosis is increasingly diagnosed in humans. Our study highlights the urgent need for increased surveillance and improved diagnostic strategies worldwide, particularly in regions with significant human-wildlife contact.

Population genetic studies have traditionally relied on data from short tandem repeat (STR) markers, known as microsatellites, to produce individual genotypes used in population genetics research. However, size fragment analysis from traditional capillary electrophoresis presents scoring challenges and limits data comparisons among labs. Here, we present a new, cost-effective universal microsatellite genotype-by-sequencing assay for Canis species that allows for unambiguous allele calls, flags homoplasy for more accurate assignment tests and estimates of diversity, and improves genotyping output from low-template DNA. We note size homoplasy in 18 of 26 loci, with the number of alleles being 32% higher in the dataset that included sequence mutations (Namut = 334) compared to the dataset on the basis of size alone (Nalen = 253). Assignment tests with Bayesian cluster analysis were similar for both datasets, although 64 of 84 samples had higher assignment values to their primary cluster when mutations were considered. We document and code a list of sequence mutations associated with each locus and propose a framework for building an accessible, universal STR dataset for wolves, coyotes, and dogs that improves cluster assignments and admixture estimates in a system with complex demography and hybridization patterns. Overall, the assay provides an improved microsatellite method of genetic monitoring to aid conservation of wolf populations.

Type 2 diabetes (T2D) presents a global healthcare burden. Despite widespread use of non-insulin glucose lowering therapies, many individuals still require insulin to achieve recommended target glycated haemoglobin (HbA1c). Insulin injections improve HbA1c but can lead to problematic hypoglycaemia. The objective of this study is to determine whether fully closed-loop insulin delivery improves HbA1c at 26 weeks compared with standard insulin therapy with continuous glucose monitoring (CGM) in adults with T2D. This study adopts an open-label, multinational, randomised, single-period parallel design and aims to randomise 224 adults with T2D to either standard insulin therapy with CGM (control group) or fully closed-loop insulin delivery (intervention group) for a period of 26 weeks. Participants will complete a run-in period of 2-3 weeks wearing a masked CGM followed by randomisation to either the control or intervention group. The primary endpoint is the between-group difference in HbA1c at 26 weeks. Key endpoints include time in target glucose range (3.9-10.0&#x2009;mmol/L), mean sensor glucose, time above range (>10.0&#x2009;mmol/L) and non-inferiority for time below target (<3.9&#x2009;mmol/L) over the 26-week study period. Secondary outcomes include standard CGM metrics, binary metrics for HbA1c, total daily insulin dose, body mass index, blood pressure, fasted lipid profile, renal function and liver function. Safety will be assessed by the frequency of severe hypoglycaemic episodes and other adverse events. Utility will be assessed by CGM and closed-loop system use. The impact of fully closed-loop will be assessed using validated questionnaires and interviews. The study has received ethical approval from the East of England Cambridgeshire and Hertfordshire Research Ethics Committee (24/EE/0149) in the UK. Ethical approval for non-UK site has been obtained by local Research Ethics Committees.Results will be disseminated by peer-reviewed publications and conference presentations, and findings will be shared with people living with diabetes, healthcare providers and relevant stakeholders. NCT06579404.

This article will focus on the use of AI tools in diagnosis and patient treatment in hospitals and health care systems. AI vendors promise efficiencies in workplaces: various forms of AI are already being developed to read x-rays and other medical scans, to diagnose a wide range of patient conditions, and to offer a partnership (or risk displacement) of physicians. AI is being pushed to transform medical diagnostics, care quality, patient safety, clinical experience, and efficiencies all over hospital operations. These AI technologies however are still novel and new, and studies proving efficacy or disclaiming it are often based on small scale studies or other limitations.I will take a quick look at the tools that comprise the use of AI in health care and the claims of effectiveness of AI alone or in partnership with physicians in making clinical decisions. I will then look at the ways in which AI can fail to meet its promises, causing serious harms. Finally, I will examine the prospects of a hybrid regulatory/liability model to regulate AI risks as hospitals and providers expand their uses of AI tools.

Nicotiana attenuata and Nicotiana obtusifolia are two wild tobacco species from the Solanaceae plant family, which produce diverse specialized metabolites and have been established as ecological model systems for studying plant-insect interactions. The previously published N. attenuata and N. obtusifolia genomes were draft assemblies with low assembly contiguity and a high proportion of gaps, limiting comparative genomic analysis. Here, we performed chromosome-level genome assemblies and annotations of these two species using long-read sequencing and Hi-C data. Both N. attenuata and N. obtusifolia genomes were anchored to 12 chromosomes, with assembled genome sizes of 2.2&#x2009;Gb and 1.3&#x2009;Gb, respectively. We achieved high BUSCO completeness at the protein level, with 99.3% for N. attenuata and 97.9% for N. obtusifolia. The reference genomes of N. attenuata and N. obtusifolia presented in this study will advance the understanding of metabolic innovations in Solanaceae plants.