|Wolf in Algonquin Provincial Park|
|Modern range of North American Canis|
The eastern wolf (Canis lupus lycaon or Canis lycaon), also known as the Eastern Canadian wolf, Eastern Timber wolf, Eastern Canadian red wolf, Algonquin wolf or deer wolf, is a canid native to the northeastern side of North America's Great Lakes region as well as southeastern Canada. It is a medium-sized canid which, like the red wolf, is intermediate in size between the coyote and the gray wolf. It primarily preys on white-tailed deer, but may occasionally attack moose and beavers. They also prey on muskrats and mice.
The eastern wolf's taxonomic classification has been under review beginning c. 2000, with various suggestions having been presented as to its derivation, including its being a subspecies of gray wolf, its being conspecific with the red wolf, gray wolf–coyote hybridization, and classification as a separate species within Canis. The eastern wolf is recognized as a gray wolf subspecies by Mammal Species of the World (as of 2005[update]).
The eastern wolf is currently listed as a threatened species under COSEWIC and with the Committee on the Status of Species at Risk in Ontario (COSSARO), because "new genetic analyses indicate that the eastern wolf is not a subspecies of grey wolf" versus earlier theories that it was a result of hybridization with both gray wolves and coyotes. The eastern wolf is particularly susceptible to hybridization, due to its close relationship to the coyote and its ability to bridge gene flow between both coyotes and gray wolves. Furthermore, human persecution over a period of 400 years caused a population decline which reduced the number of suitable mates, thus facilitating coyote gene swamping into the eastern wolf population. Aside from posing a threat to a unique species, the resulting eastern wolf–coyote hybrids are too small in size to substitute pure eastern wolves as apex predators of moose and deer. The main nucleus of pure eastern wolves is currently concentrated within Algonquin Provincial Park, eastern Ontario and south central Quebec. However, a 2016 study concluded that even these eastern wolves have about 32% coyote ancestry.
The taxonomic status of the eastern wolf is debated. It has been described as the species C. lycaon, a subspecies of the gray wolf C. lupus lycaon, the product of coyote introgression into the gray wolf, the same species as the red wolf, or a result of hybridization between the gray wolf and the red wolf. The first published name of a taxon belonging to the genus Canis from North America is Canis lycaon. It was published in 1775 by the German naturalist Johann Schreber who had based it on the earlier description and illustration of one specimen that was thought to have been captured near Quebec. It was later reclassified as a subspecies of gray wolf by Edward Goldman. The taxonomic reference Catalogue of Life, and the mammalogist W. Christopher Wozencraft writing in Mammal Species of the World (2005), classifies the eastern wolf as a subspecies of Canis lupus.
When European settlers first arrived to North America, the coyote's range was limited to the western half of the continent. They existed in the arid areas and across the open plains, including the prairie regions of the midwestern states. Early explorers found some in Indiana and Wisconsin. From the mid-1800s coyotes began expanding beyond their original range.
The taxonomic debate regarding North American wolves can be summarised as follows:
There are two prevailing evolutionary models for North American Canis: (i) a two-species model that identifies grey wolves (C. lupus) and (western) coyotes (Canis latrans) as distinct species that gave rise to various hybrids, including the Great Lakes-boreal wolf (also known as Great Lakes wolf), the eastern coyote (also known as Coywolf/brush wolf/tweed wolf), the red wolf and the eastern wolf; and (ii) a three-species model that identifies the grey wolf, western coyote and eastern wolf (C. lycaon) as distinct species, where Great Lakes-boreal wolves are the product of grey wolf × eastern wolf hybridization, eastern coyotes are the result of eastern wolf × western coyote hybridization, and red wolves are considered historically the same species as the eastern wolf, although their contemporary genetic signature has diverged owing to a bottleneck associated with captive breeding.
The evolutionary biologist Robert K. Wayne, whose team is involved in an ongoing scientific debate with the team led by Linda K. Rutledge, describes the difference between these two evolutionary models: "In a way, it is all semantics. They call it a species, we call it an ecotype."
Mitochondrial DNA (mDNA) passes along the maternal line and can date back thousands of years. In 1991, a study of the mitochondrial DNA (mDNA) sequences of gray wolves and coyotes from across North America found that the gray wolves of the Minnesota, Ontario, and Quebec regions possessed coyote genotypes. The study proposes that dispersing male gray wolves were mating with coyote females in deforested areas bordering wolf territory.
In 2000, a study looked at red wolves and eastern Canadian wolves. The study agreed that these two wolves readily hybridize with the coyote. The study used 8 microsatellites (genetic markers taken from across the genome of a specimen). The phylogenetic tree produced from the genetic sequences showed red wolves and eastern Canadian wolves clustering together. These then clustered next closer with the coyote and away from the gray wolf. A further analysis using mDNA sequences indicated the presence of coyote in both of these two wolves, and that these two wolves had diverged from the coyote 150,000–300,000 years ago. No gray wolf sequences were detected in the samples. The study proposes that these findings are inconsistent with the two wolves being subspecies of the gray wolf, that red wolves and eastern Canadian wolves evolved in North America after having diverged from the coyote, and therefore they are more likely to hybridize with coyotes. In 2009, a study of eastern Canadian wolves using microsatellites, mDNA, and the paternally-inherited yDNA markers found that the eastern Canadian wolf was a unique ecotype of the gray wolf that had undergone recent hybridization with other gray wolves and coyotes. It could find no evidence to support the findings of the earlier 2000 study regarding the eastern Canadian wolf. The study did not include the red wolf. This study was quickly rebutted on the grounds that it had misinterpreted the findings of earlier studies that it relied upon, nor did it provide a definition for a number of the terms that it used, such as "ecotype".
In 2011, a study compared the genetic sequences of 48,000 single nucleotide polymorphisms (mutations) taken from the genomes of canids from around the world. The comparison indicated that the red wolf was about 76% coyote and 24% gray wolf with hybridization having occurred 287–430 years ago. The eastern wolf was 58% gray wolf and 42% coyote with hybridization having occurred 546–963 years ago. The study rejected the theory of a common ancestry for the red and eastern wolves.
Also in 2011, a scientific literature review was undertaken to help assess the taxonomy of North American wolves. One of the findings proposed was that the eastern wolf is supported as a separate species by morphological and genetic data. Genetic data supports a close relationship between the eastern and red wolves, but not close enough to support these as one species. It was "likely" that these were the separate descendants of a common ancestor shared with coyotes. This review was published in 2012.
In 2012, one study reviewed a subset of the 2011 study's SNP data and proposed that its methodology had skewed the results, and that the eastern wolf is not a hybrid but a separate species. Therefore, the study proposes that there are 3 wolf species in North America. Another study of both mDNA and yDNA in wolves and coyotes by the same authors indicates that the eastern wolf is genetically divergent from the gray wolf and is a North American evolved species with a long standing history. The study could not dismiss the possibility of the eastern wolf having evolved from an ancient hybridization of gray wolf and coyote in the Late Pleistocene or Early Holocene. Another study by the same authors found that eastern wolf mDNA genetic diversity had been lost after their culling in the early 1960s, leading to the invasion of coyotes into their territory and introgression of coyote mDNA.
In 2014, the National Center for Ecological Analysis and Synthesis was invited by the United States Fish and Wildlife Service to provide an independent review of its proposed rule relating to gray wolves. The Center's panel findings were that the proposed rule was heavily dependent upon the analysis contained in a scientific literature review conducted in 2011 (Chambers et al.), that this work was not universally accepted and that the issue was "not settled", and that the rule does not represent the "best available science". Also in 2014, an experiment to hybridize a captive western gray wolf and a captive western coyote was successful, and therefore possible. The study did not assess the likelihood of such hybridization in the wild.
In 2015, the Committee on the Status of Endangered Wildlife in Canada changed the designation of the eastern wolf to Canis cf lycaon (Canis species believed to be lycaon) and a species at risk. Later that year, a study compared the DNA sequences using 127,000 single-nucleotide polymorphisms (mutations) of wolves and coyotes. The study indicated that eastern wolves were a distinct genomic cluster, which did not exclude a possibility that a gray wolf x eastern wolf hybrid (C. l. lycaon) historically inhabited the same area as the eastern wolf. The study did not include red wolves.
In 2016, a study of mDNA once again indicated the Eastern wolf as a coyote–wolf hybrid.
In 2018, a study looked at the y-chromosome male lineage of canines. The unexpected finding was that the one Great Lakes wolf specimen included in this study showed a high degree of genetic divergence. Previous studies propose the Great Lakes wolf to be an ancient ecotype of the gray wolf that had experienced genetic introgression from other types of gray wolves and coyotes. The study called for further research into the y-chromosomes of coyotes and wolves to ascertain if this is where this unique genetic male lineage may have originated from.
In 2016, a whole-genome DNA study proposed, based on the assumptions made, that all of the North American wolves and coyotes diverged from a common ancestor less than 6,000–117,000 years ago. The study also indicated that all North America wolves have a significant amount of coyote ancestry and all coyotes some degree of wolf ancestry, and that the red wolf and Great Lakes region wolf are highly admixed with different proportions of gray wolf and coyote ancestry. One test indicated a wolf–coyote divergence time of 51,000 years before present that matched other studies indicating that the extant wolf came into being around this time. Another test indicated that the red wolf diverged from the coyote between 55,000-117,000 years before present and the Great Lakes region wolf 32,000 years before present. Other tests and modelling showed various divergence ranges and the conclusion was a range of less than 6,000 and 117,000 years before present. The study found that coyote ancestry was highest in red wolves from the southeast of the United States and lowest among the Great Lakes region wolves.
The theory proposed was that this pattern matched the south to north disappearance of the wolf due to European colonization and its resulting loss of habitat. Bounties led to the extirpation of wolves initially in the south east, and as the wolf population declined wolf–coyote admixture increased. Later, this process occurred in the Great Lakes region with the influx of coyotes replacing wolves, followed by the expansion of coyotes and their hybrids across the wider region. The Great Lakes wolves largely reflect lineages that have descendants in the modern wolf and coyote populations, but also reflect a distinct gray wolf ecotype which may have descendants in the modern wolf populations. The proposed timing of the wolf/coyote divergence conflicts with the finding of a coyote-like specimen in strata dated to 1 million years before present.
In 2017 a group of canid researchers challenged the recent finding that the red wolf and the eastern wolf were the result of recent coyote–wolf hybridization. The group highlight that no testing had been undertaken to ascertain the time period that hybridization had occurred and that by the previous study's own figures the hybridization could not have occurred recently but supports a much more ancient hybridization. The group found deficiencies in the previous study's selection of specimens and the findings drawn from the different techniques used. Therefore, the group argues that both the red wolf and the eastern wolf remain genetically distinct North American taxa. This was rebutted by the authors of the earlier study.
Physical description and behavior
Charles Darwin described the eastern wolf as being a lightly-built, greyhound-like animal that pursued deer, as opposed to the bulkier, shorter-legged gray wolf. The eastern wolf's fur is typically of a grizzled grayish-brown coloration mixed with cinnamon. The flanks and chest are rufous or creamy, while the nape, shoulder and tail region are a mix of black and gray. Unlike gray wolves, eastern wolves rarely produce melanistic individuals. The first documentend all-black eastern wolf was found to have been an eastern wolf–gray wolf hybrid. Like the red wolf, the eastern wolf is intermediate in size between the coyote and gray wolf, with females weighing 23.9 kilograms (53 lb) on average and males 30.3 kilograms (67 lb). Like the gray wolf, its average lifespan is 3–4 years, with a maximum of 15 years. Their physical sizes that sets them intermediate between gray wolves and coyotes are actually believed to be more related to their adaptations to an environment with predominately medium-sized prey similar to the case with the Mexican wolves in the southern USA rather than their close relationship to red wolves and coyotes.
The eastern wolf primarily targets small to medium-sized prey items like white-tailed deer and beaver, unlike the gray wolf which can effectively hunt large ungulates like caribou, elk, moose and bison. The average territory ranges between 110–185 km², and the earliest age of dispersal for young eastern wolves is 15 weeks, much earlier than gray wolves.
History, hybridization and conservation
Before the arrival of Europeans, eastern wolves may have numbered at 64,500–90,200 individuals. The species ranged throughout the wooded and open areas of eastern North America, from the Maritime provinces and southern Quebec to approximately the southern United States and westward to the Great Plains. The region's indigenous human populations didn't fear eastern wolves, though they did occasionally catch them in traps, and their bones occur in native shell heaps. The earliest written records of the eastern wolf were in the writings of Jacques Cartier in 1535 and in Marc Lescarbot's Histoire de la Nouvelle-France (1609), where he wrote that the animal was common in Acadia.
Early European settlers often kept their livestock on eastern wolf-free outer islands, though animals kept in pasture on the mainland were vulnerable, to the point that a campaign against eastern wolves was launched in the early years of the Plymouth and Massachusetts Bay Colonies, in which both settlers and natives participated. A bounty system was put into effect, offering higher rewards for adult wolves, with their heads exposed on hooks in meetinghouses. Nevertheless, eastern wolves were still plentiful enough by the early 18th century to warrant the settlers of Cape Cod discussing the building of a high fence between Sandwich and Wareham to keep eastern wolves out of grazing lands. The scheme failed, though the settlers continued to utilize wolf pits, a wolf trapping technique learned from the region's indigenous peoples. Eastern wolf numbers declined noticeably shortly before and after the American Revolution, particularly in Connecticut, where the wolf bounty was repealed in 1774. Eastern wolf numbers, however, were still high enough to cause concern in the more sparsely populated areas of southern New Hampshire and Maine, with wolf hunting becoming a regular occupation among settlers and natives alike. By the early 19th century, few eastern wolves remained in southern New Hampshire and Vermont.
Prior to the establishment of Algonquin Provincial Park in 1893, the eastern wolf was common in central Ontario and the Algonquin Highlands. It continued to persist throughout the late 1800s, despite extensive logging and efforts by park rangers to eliminate it, largely due to the sustaining influence of plentiful prey items like deer and beaver. By the mid-1900s, there were as many as 55 eastern wolf packs in the Park, with an average of 49 wolves being killed annually between 1909–1958, until they were given official protection by the Ontario government in 1959, by which time the eastern wolf population in and around the Park had been reduced to 500–1000 individuals. Nevertheless, between 1964–1965, 36% of the Park's wolf population was culled by researchers trying to understand the reproduction and age structure of the population. This cull coincided with the expansion of coyotes into the park, and lead to an increase in eastern wolf–coyote hybridization. Introgression of gray wolf genes into the eastern wolf population also occurred across northern and eastern Ontario, into Manitoba and Quebec, as well as into the western Great Lakes states of Minnesota, Wisconsin, and Michigan. Despite protection within the Park boundaries, there was a population decline in the east side of the Park between 1987–1999, with an estimated number of 30 packs by 2000. This decline exceeded annual recruitment, and was attributed to human-caused mortality, which mostly occurred when dispersing animals left the Park in search of deer during the winter months, and when pack ranges overlapped with Park boundaries. By 2001, protection was extended to eastern wolves occurring in the outskirts of the Park. By 2012, the genetic composition of the Park's eastern wolves was roughly restored to what it was in the mid-1960s than in the 1980s-1990s, when the majority of wolves had large amounts of coyote DNA.
In 2013, an experiment which produced hybrids of coyotes and northwestern gray wolves in captivity using artificial insemination contributed more information to the controversy surrounding the eastern wolf's taxonomy. The purpose of this project was to determine whether the female western coyotes are capable of bearing hybrid western gray wolf-coyote pups, as well as to test the hybrid theory surrounding the origin of the eastern wolves. The resulting six hybrids produced in this captive artificial breeding were later transferred to the Wildlife Science Center of Forest Lake in Minnesota, where their behaviors were studied.
Relationships with humans
In Algonquin folklore
The eastern wolf is prominently portrayed in Algonquin mythology, where it is referred to as ma-hei-gan or nah-poo-tee in the Algonquian languages. It is the spirit brother of the Algonquian folkhero Nanabozho, and assisted him in several of his adventures, including thwarting the plots of the malicious anamakqui spirits and assisting him in recreating the world after a worldwide flood.
Since the discovery in 1963 that eastern wolves answered human imitations of their howls, Algonquin Provincial Park began its Public Wolf Howls attraction, where as many as 2,500 visitors are led on expeditions into areas where eastern wolves were sighted the night before and listen to them answering the Park staff's imitation howls. By 2000, 85 Public Wolf Howls had been held, with over 110,000 people having participated. The Park considers the attraction as the cornerstone of its wolf education program, and credits it with changing public attitudes towards wolves in Ontario.
Attacks on humans
Since the early 1970s, there have been several incidents of bold or aggressive behavior towards humans in Algonquin Provincial Park. Between 1987 and 1996, there were four instances of wolves biting people. The most serious case occurred in 1998, when a male wolf that had been long noted to be unafraid of humans stalked a couple walking their four-year-old daughter in September that year, losing interest when the family took refuge in a trailer. Two days later, the wolf attacked a 19-month-old boy, causing several puncture wounds on his chest and back before being driven off by campers. After the animal was killed later that day, it was found to be non-rabid, and had a DNA profile typical of wolves of the area, thus indicating it was not a hybrid.
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