Does Killing Coyotes Increase Their Population?
Part two of a two-part series
At first glance, some may consider the above question simple. Surely, if there are five coyotes and you kill three of them, there will be two left. However, as with many aspects of nature, science tells us that the matter is far more complex than it seems. And as a sentient species playing a significant role within ecosystems, benefiting wildlife and humans, coyotes have earned more than a mere glance when it comes to responsible management, and the indiscriminate, extreme killing of their kind.
Current Artificial Population Manipulation For Sport
While science-based game management and responsible hunting practices are an accepted form of subsistence, our current indiscriminate year-round killing of coyotes is an outdated method used in an attempt to decrease predators to overpopulate prey for hunting. The thought process is, the more coyotes you kill, the more deer hunters will have to shoot, which is not always for food, but for recreation.
However, attempts to boost the population of one species at the detriment of another, or for the purpose of recreation, is ecologically harmful and highly unwarranted. Modern biology confirms that a natural balance will continue conservation while also providing plenty of prey for human harvest.
Such attempts are also often ineffective, as the deer population is highly dependent upon the abundance of food sources and the nutrition of breeding females, which in part, is how they thrive despite fawn predation and human hunting. Inflated deer populations cause over-browsing, destruction of woodlands, an adverse impact on other species, and the spread of disease. Coyotes do not primarily prey on fawn nor often kill adult deer, but help to prevent overpopulation and cull the sick when they do; naturally helping to keep the deer population and ecosystems balanced, healthy, and stable overall, which is beneficial from a long-term subsistence perspective.
Artificial population manipulation, in combination with indiscriminate hunting, is also ineffective from a coyote population standpoint due to their social structure and behaviors.
Coyote Social Structure & Behavior
To grasp how coyote killing can contribute to population increase, one must first understand coyote structure and behavior. Scientists throughout the nation have been gathering coyote facts for decades, often conducting studies by fitting them with GPS collars and observing their behavior over various periods of time. That research tells us that coyotes live in packs, sometimes in pairs or as solitary individuals; categorized as residents or transients.
'Resident' coyotes are those living in pairs or packs, who represent the majority and a higher percentage of the breeding population. Only the alpha pair within a pack mate, often monogamously. Each pack has a consistent, established home territory which they maintain and protect from other coyotes. The reported home ranges of resident coyotes are between 1.5 and 30 square miles. Territory and pack size is dependant upon the habitat, food sources and the level of urbanization. Resident coyotes are less likely to cause human conflict because they're trained by their parents to avoid it.
'Transients' are the lone wonders of the species. They are solitary coyotes who cover greater distances throughout the landscape, attempting to find a mate or their own territory. They're typically younger coyotes who were orphaned or recently dispersed from their parents, coyotes who recently lost their mate, and sometimes those who are sick or injured. Their reported range is approximately 100 square miles or more and can be over 10 times that of resident coyotes. Transients may stay within a particular area for some time; however, they do not defend it. Transients are sometimes more prone to prey on livestock or become habituated. This isn't because they're 'mean,' rather that they're often desperate for food, or inexperienced; sometimes due to the death of their parents before they were trained to hunt wild prey and avoid humans. Conflict with these coyotes can be prevented with appropriate coexistence methods.
Differentiating Between A Resident & Transient Is Not So Easy
A singular coyote does not necessarily indicate that they are a transient, and a transient doesn't definitively indicate a 'problem coyote.' Although resident coyotes sometimes hunt in packs, they also hunt alone and can live solitarily during certain parts of their lives. A resident coyote might hunt or live alone if their mate was recently killed. Males may also hunt alone for their mate and pups, making the pup-rearing months that much more of a vulnerable time. If one or both parents are killed, the chances of pups dying due to starvation increase. Unless one was to track a specific coyote for a considerable time-frame, differentiating between a resident and a transient, and whether or not they have pups to feed can be challenging.
Failed Attempts At Targeted Lethal Removal Contributes to Further Conflict & Population Increase
Depending on a coyote's level of habituation, it's potentially reversible with hazing. However, a specific coyote preying on livestock or demonstrating habituation beyond the point of reversal could justify lethal removal. Such actions require extensive skill and expertise. Due to their wiliness, it's difficult to identify a specific coyote causing an issue unless it's done during an attack. As the NH Fish and Game acknowledges, resident coyotes are unlikely to depredate; doing a farm good by preying on rodents and protecting the territory from other predators. If an attack occurs, it's possible that it wasn't caused by a coyote at all, or that it was an improperly trained or habituated transient who made their way into the territory.
If coyotes are indiscriminately killed in the area, it's highly likely that non-problematic coyotes who were benefiting the farmer and ecosystem will be inadvertently killed.
This removes those valued coyotes from the landscape, allowing habituated coyotes to move into the territory in their place, and also potentially contributing to an overall increase in population.
How Indiscriminate Coyote Hunting Contributes To Population Increase
Hunting and trapping coyotes can effectively cause an initial, short-term population decrease. It goes back to that shortsighted concept; dead coyotes equals fewer coyotes. However, those methods contribute to an expansion in coyote range and population long-term, especially when hunting is done so indiscriminately and excessively.
For over 100 years, attempts to decrease the coyote population through indiscriminate, year-long hunting have failed. Coyotes have expanded their range by an estimated 40% since the 1950s, despite extreme, unregulated killing. That phenomenon has led to scientific studies to determine how, and the results have shown two potential explanations; compensatory reproductive response and compensatory immigration response.
Compensatory Reproductive Response & Immigration Response
With only the alpha pair of a coyote pack mating, the other 'beta' females remain behaviorally sterile. Science shows that when one or both of the alpha pair is killed, that disrupts their social structure and the other females in the pack begin to breed. Science has also shown that when coyote populations decrease, food sources become more abundant for those who remain. In turn, that increases the nutrition of breeding females, which increases egg production, causing larger litters. Therefore, fewer coyotes one year can mean more coyotes the following year. Those adaptable characteristics are referred to as a compensatory reproductive response.
When resident coyotes are killed, that also opens up the territory that they used to protect, allowing transient coyotes to move in. This is referred to by scientists as a compensatory immigration response. Not only does it cause range expansion, but contributes to population increase, as transients will also move in to mate with former behaviorally sterile pack members when alpha pairs are killed.
The study of compensatory reproductive response has yielded varying conclusions, depending on the study size, length, and specific pack. When 'beta' females within a pack began to breed due to pack disruption, they may have trouble successfully reproducing depending on their age. However, pack sizes and age of members vary, and increased breeding among more coyotes, regardless of age, can yield increased population overall.
Where the theory that indiscriminate hunting will reduce the coyote population has failed, the scientific theories of compensatory reproduction and immigration response in coyotes have held up to scientific scrutiny for at least the past 46 years. The theories have gained the respect and acceptance of scientists and wildlife agencies across the nation, including the New York Department of Environmental Conservation, a state that does not allow year-round coyote hunting. A few relevant scientific studies, which include those based on scientific evidence gathered during the observation of coyotes, are listed below.
Knowlton,1972: Noted the death of alpha pairs in packs stimulates breeding among formerly behaviorally sterile pack members, promotes immigration of transient coyotes, and that litter size can be affected by population density; reporting average litter sizes of 4.3 at high coyote densities and 6.9 at low coyote densities(I)
Connolly and Longhurst, 1975/ Connolly, 1978: Noted that in most situations, killing coyotes even at rates of up to 70% of their population merely stimulates reproduction and aggravates the problem.(II)
Bekoff, 1977: Noted that in more coyote females breed when food is abundant and that during years when rodent populations are high, as many as 75% of yearling females may breed.(III)
New York State DEC, 1991: Noted females will not breed if food is in short supply or their numbers are too high for the available food and space, liter sizes will be smaller with less abundant food sources, random hunting and trapping and year-round hunting will not reduce coyote populations, and if a breeding female is removed, a previous non-breeder may take her place.(VI)
Connolly, 1995: Noted that upon review of the Connolly and Longhurst model of 1975, those biological concepts seemed just as valid in 1995 and that new studies have tended to reaffirm those coyote population mechanics rather than prove them wrong.(V)
Fox and Papouchis, 2005: Noted the failure of extreme, indiscriminate killing of coyotes due to their adaptability within their diet, as well as reproductive and immigration response, and that resources would be better spent on long-term, humane coexistence methods.(VI)
Schadler, 2010: Noted that pack disruption stimulates breeding among previously behaviorally sterile pack members and that coyote fertility varies based on food availability; improved nutrition releases hormonal signals that result in more egg production in females, causing an increase of population upon the next mating cycle following a temporary decrease in population.(VII)
Minnie, Gaylard, and Kerley, 2015: Noted compensatory reproduction and immigration response in adaptive and indiscriminately killed predators such as the jackal and the coyote.(VIII)
Crabtree, 2015: Explained the scientific theory of compensatory reproductive response; further solidifying the growing acceptance of the predator reproductive response theory among scientists.(IX)
Kierepka, Kilgo and Rhodes, 2017: Noted that coyotes recover from intensive trapping via reproduction and immigration, which likely make preventing compensation difficult.(X)
Responsible Conservation and Game Management
Conservation must be based on the best available science, not ineffective artificial manipulation in an attempt to increase prey for sport or uneducated misconceptions that a species is an unbeneficial nuisance, which is how coyotes are hunted today.
The coyote's abilities to adapt and survive have been exploited for unsporting activities and the unethical waste of the valued sentient beings and the integral part of healthy ecosystems that they are. Coyote killing contests granting prizes for the most coyotes killed, coyotes hunted relentlessly and indiscriminately year-round even while giving birth and raising their pups; causing the slow deaths of pups due to starvation;
This is not responsible
This is not ethical
This is not efficient
This is not conservation
To be considered a conservationist, a hunter must contribute to the overall health of an ecosystem. The impact of hunting any species is highly situational; requiring knowledge of the ecosystem's biodiversity, as well as the behaviors and the role of each species within it. When a hunter kills an animal, they must know what the short and long-term impact on that ecosystem and species will be.
Responsible coyote management additionally includes differentiating between a transient or a resident, whether or not they are part of an alpha pair, if they have a liter to feed, as well as if a specific coyote is truly causing conflict and not merely residing near a farm or in the woods adjacent to a neighborhood.
How do we improve our management of coyotes? - We have the answer; we just have to acknowledge and implement it.
A regulated coyote hunting season, with closure during the pup-rearing months, will help prevent the killing of parents; reducing the chances of pups dying a slow death of starvation. Equally important, a regulated hunting season will help prevent indiscriminate, extreme and counterproductive coyote killing by requiring that the Fish and Game Commission review the hunting of coyotes within each wildlife management unit (WMU), based on the ecosystems within those areas, as the Commission currently does with all other furbearers and game species (excluding certain fish). Additionally, required take reporting will provide valuable data on the number of coyotes killed, insight into the coyote population, and how it corresponds with or is potentially impacting the white-tailed deer population within each WMU.
Such determinations must also be done in conjunction with the consideration of the best science regarding compensatory reproductive and immigration response, for the most effective and efficient approach.
With indiscriminate hunting and trapping contributing to human-coyote conflict, as well as over-all coyote expansion and population increase, state resources are often better spent on public education regarding humane coexistence, safe and practical methods to protect domestic animals, as well as general insight about coyote behavior.
We have the responsibility to conserve all wildlife species, as well as the natural biological diversity, integrity and environmental health within our ecosystems.
With the human population, habitat loss, and the public's interest in humane management all increasing, efficient long-term management and safe coexistence with wildlife must be considered. Coyotes have adapted, survived, and benefited us and our ecosystems, despite our immense, indiscriminate, inhumane and extreme killing of their kind. The time has come to acknowledge what we have learned from the coyote, along with the best available science to better ourselves and our approach towards managing this incredible species. Acknowledgment of such science and reduced indiscriminate coyote hunting is not only in the best interest of the coyote but other wildlife species and would lend to ethical, long-term conservation, for New Hampshire residents here in the present, as well as future generations.
(I) Knowlton, F.F. 1972. "Preliminary Interpretations of Coyote Population Mechanics with Some Management Implications." Journal of Wildlife Management, 36:369-382.
(II) Connolly, G.E. and Longhurst, W.M. 1975. "The effects of control on coyote populations." Univ. Calif., Div. Agric. SCI. Bull. 1872. 37pp;
Connolly, G.E. 1978. "Predator control and coyote populations a review of simulation models." Pages 327-345 in M Bekoff (ed.) Coyotes: Biology, Behavior and Management. Academic Press, NY 384pp.
(III) Bekoff, M. 1977. "Canis latrans. Mammalian Species." American Society of Mammalogists, 79: 1-9.
(IV) Bureau of Wildlife, Division of Fish and Wildlife, New York State DEC, and Cornell Cooperative Extension Dept. of Natural Resources, New York State College of Agriculture and Life Sciences, 1991, "The Status and Impact of Eastern Coyotes in Northern New York."
(V) Connolly, G.E. 1995. "The Effects of Control on Coyote Populations: Another Look." Symposium Proceedings- Coyotes in the Southwest: A Compendium of Our Knowledge, 36.
(VI) Fox, C.H. and Papouchis, C.M. 2005. "Coyotes in Our Midst: Coexisting with an Adaptable and Resilient Carnivore."
(VII) Schadler, C. 2010. "Coyote: To understand Eastern coyotes, look to their wolf relatives." Wildlife Journal, November/December 2010
(VIII) Minnie, L., Gaylard, A., Kerley, G. I.H. 2015. "Compensatory life-history responses of a mesopredator may undermine carnivore management
efforts." Journal of Applied Ecology, 1365-2664.12581
(IX) Crabtree, R. 2015, "Understanding the Compensatory Reproduction Response to Killing Coyotes."
(X) Kierepka, E.M., Kilgo, J.C., and Rhodes, O.E. 2017, "Effect of compensatory immigration on the genetic structure of coyotes," The Journal of Wildlife Management 81(8):1394–1407; 2017; DOI: 10.1002.