Both red (Vulpes vulpes) and gray fox (Urocyon cinereoargenteus) population trends in Ohio have been declining over the past 20 years, with the greater decrease occurring in gray foxes. These declines are correlated with the increase in the coyote (Canis latrans) population. Coyotes first appeared in Ohio in 1919; however, they remained uncommon until the 1980s. During 1979 and 1980, there were 336 possible encounters with wild coyotes reported in 46 counties. By 1990, coyotes likely occurred in all of Ohio’s 88 counties. Since that time, population size based on bowhunter survey data has continued to increase and has only begun to stabilize.
Coyotes are known to kill smaller canids, including red and gray foxes. Furthermore, coyote presence may influence fox populations by forcing individuals into less desirable habitats and/or removing food sources through competition. Presently, red fox populations appear to be recovering somewhat by moving closer to human habitations, particularly to rear young, and the greater concern is for gray fox populations. However, the ability of gray foxes to climb trees and their preference for thick understory decreases the likelihood that coyote presence alone is impacting gray fox numbers.
In addition to increasing coyote populations, raccoon (Procyon lotor) populations in Ohio have also increased considerably over the past several decades. Canine distemper is common in raccoons, and they periodically experience canine distemper outbreaks from which the population recovers. Conversely, gray foxes are particularly sensitive to canine distemper, and it has been known to decimate gray fox populations. Therefore, cause-specific mortality rates are needed to aid in identifying the reasons for gray fox decline.
During the 1990s, raccoon population sizes and their distribution peaked across North America. The dramatic increase in raccoon abundance across North America began in the 1940s, with a simultaneous increase in distribution. From 1920 to 1987, the total estimated geographic range in North America increased from 6.6 million square kilometers to 8.8 million square kilometers. Additionally, it has been estimated that there were 15-20 times as many raccoons in North America during the 1980s as there were in the 1930s.
However, coyotes and raccoons are not likely the sole reasons for the dramatic decline in gray fox numbers. Pelt prices reached an all-time high in the late 1970s and early 1980s, resulting in record numbers of furbearing species taken, including the gray fox. As the average pelt price peaked at over $40, approximately 35,000 gray foxes were harvested in the 1978-1979 season alone. Pelt prices dropped somewhat but remained high through the mid- to late-1980s. Prices began to rise again in the early 1990s; however, gray fox harvest did not increase and remained low, despite increased trapping efforts. The lack of correlation between pelt price and fox harvest provides additional evidence for the timing of the initial fox decline, as well as its severity. Despite increasing pelt prices in the mid-1990s, gray foxes were simply not available to be taken, and harvest continued to decline.
Thus, the combination of the invasion of coyotes, increased raccoon populations and associated disease, and record-high harvests have likely worked together or synergistically to the detriment of the gray foxes. The timing and intensity of these events could represent a perfect storm that adversely affected gray fox populations. As gray foxes declined dramatically in Ohio, similar declines have occurred in a number of Midwestern states, although the declines have not been well studied. Illinois reports a decline beginning 25 years ago, similar to that in Ohio. Indiana is seeking observations of the declining gray fox in that state. Missouri’s bowhunter trends mirror those of Ohio. The Iowa Department of Natural Resources states that the gray fox has declined since the 1980s. Understanding the reasons for the gray fox population decline is essential to promoting action from state natural resource agencies to enact programs to increase gray fox numbers and health.
We are currently seeking to document the distribution and relative abundance of gray foxes in Ohio. For this reason, we ask for the public to report all gray fox sightings, whether they occurred this year or some years in the past.
Please report gray fox sightings to suzie.prange@appalachian-wri.com. You can also post pics and videos on our community Facebook page at https://www.facebook.com/groups/awri.community.
Please follow us on Facebook (https://www.facebook.com/awriohio) and join the AWRI Facebook community to post and comment (https://www.facebook.com/groups/awri.community).
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