bioRxiv Science⌕ Search

Biology subjects

Farr, J. J.

Publications and source records attributed to Farr, J. J..

2 recordsLinked to original sources

A ten-year community reporting database reveals rising coyote boldness and associated human concern in Edmonton, Canada

In cities throughout North America, sightings of coyotes (Canis latrans) have become common. Reports of human-coyote conflict are also rising, as is the public demand for proactive management to prevent negative human-coyote interactions. Effective and proactive management can be informed by the direct observations of community members, who can report their interactions with coyotes and describe the location, time, and context that led to their interactions. To assess the predictors of human-coyote conflict, we used a web-based reporting system to collect 9,134 community-supplied reports of coyotes in Edmonton, Canada, between January 2012 and December 2021. We used a standardized ordinal ranking system to score each report on two indicators of human-coyote conflict: coyote boldness, based on the reported coyote behaviour, and human perceptions about coyotes, determined from the emotions expressed by reporters. We assigned greater conflict scores to behaviours where coyotes followed, approached, charged or contacted pets or people, and to perceptions where reporters expressed fear, worry, concern, discomfort or alarm. Using ordered logistic regression and chi-square tests, we compared conflict scores for each response variable to spatial, temporal and contextual covariates. Our analysis showed that coyotes were bolder in less developed open areas and during the pup rearing season, but human perceptions were most negative in residential areas and during the dispersal season. Reports that mentioned dogs or cats were more likely to describe bolder coyote behaviour, and those that mentioned pets or children had more negative perceptions about coyotes. Coyote boldness and human perceptions both indicated rising human-coyote conflict in Edmonton over the 10 years of reporting.

ecology↗

Heat stress does not induce wasting symptoms in the giant California sea cucumber (Apostichopus californicus)

Oceanic heat waves have significant impacts on disease dynamics in marine ecosystems. A severe sea cucumber wasting event occurred in Nanoose Bay, British Columbia, Canada, following an extreme heat wave, resulting in mass mortality of Apostichopus californicus. Here, we sought to determine if heat stress in isolation could trigger wasting symptoms in A. californicus. We exposed sea cucumbers to i) a simulated marine heat wave (22{o}C), ii) an elevated temperature treatment (17{o}C), or iii) control conditions (12{o}C). We measured the presence of skin ulcers, mortality, posture maintenance, antipredator defences, spawning, and organ evisceration during the 79-hour thermal exposure, as well as 7-days post-exposure. Both the 22{degrees}C and 17{degrees}C treatments elicited stress responses where individuals exhibited a reduced ability to maintain posture and an increase in stress spawning. The 22{o}C heat wave was particularly stressful, as it was the only treatment where mortality was observed. However, none of the treatments induced wasting symptoms as observed in the Nanoose Bay event. This study provides evidence that sea cucumber wasting is not triggered by heat stress in isolation, leaving the cause of the mass mortality event observed in Nanoose unknown.

ecology↗