The bobcat (Lynx rufus) is a North American member of the cat family. It appeared during the Irvingtonian stage (on geologic timescale is the North American faunal stage according to the North American Land Mammal Ages chronology ) around 1.8 million years ago (Appearance event ordination or AEO). Occurring from southern Canada to northern Mexico, including most of the continental United States, bobcat is an adaptable predator that is found in wooded areas, as well as urban edges, semi-desert habitat, forest edges and swampland environments. It persists in much of its original range, and populations are healthy.
Scientists had debated for very long time whether to classify bobcat as Lynx rufus or Felis rufus as part of a wider issue, which involved a question whether the four species of Lynx should be given their own genus, or be placed as a subgenus of Felis. The Lynx genus is now accepted and bobcat is listed as Lynx rufus in modern taxonomic literature.
According to experts, Lynx shared a clade (a group consisting of an ancestor and all its descendants, a single “branch” on the “tree of life”) with domestic cat (Felis), puma and leopard cat (Prionailurus) lineages, dated to 7.15 million years ago (mya); Lynx diverged first around 3.24 million years ago.
It is believed that bobcat had evolved from the Eurasian Lynx that crossed into North America by way of the Bering Land Bridge during the Pleistocene (period covering 2 million to 10,000 years ago), with ancestors arriving as early as 2.6 million years ago. It is believed that the first batch moved into the southern portion of North America, which was soon cut off from the north by glaciers. As the time passed this population evolved into modern bobcats around 20,000 years ago. The second batch of population came from Asia and settled in the northern part and evolved into the present day Canada Lynx.
Hybridization between bobcat and Canada lynx
The blynx or lynxcat is a hybrid of bobcat and one or other species of Lynx. The appearance of the offspring depends on which lynx species is used, as the European lynx (Lynx pardinus) is more heavily spotted than the Canadian Lynx (Lynx canadensis) or Eurasian Lynx (Lynx lynx). Besides breeding these hybrids in captivity they also occur naturally in the wild where lynx or bobcat cannot find member of their own species for mating.
It was in August 2003 when two hybrids from wild bobcats and Canadian lynx were confirmed after DNA analysis in the Moosehead region of Maine, USA. Three were identified in northeastern Minnesota. These were the first confirmed wild lynxcats. Mitochondrial DNA analysis established that all the hybrids were the result of matings between female lynx and male bobcats. A hybrid from male lynx and female bobcat was captured in 1998. it was radio-collared and released, but unfortunately it died due to starvation. The female hybrid was fertile. In November 2003, a spotted hybrid was seen in Illinois, far away from normal lynx territory. It was believed to be an escaped hybrid pet.
Lynxcats have been found closely resembling bobcats with larger bodies and smaller feet. They had some lynx-like features too, which included long ear tufts and almost completely black-tipped tails.
Thirteen subspecies of bobcats are currently recognized:
- L. rufus rufus (Schreber) – eastern and midwestern United States
- L. r. texensis (Mearns) – western Louisiana, Texas, south central Oklahoma, and south into Tamaulipas, Nuevo León, and Coahuila
- L. r. gigas (Bangs) – northern New York to Nova Scotia and New Brunswick
- L. r. floridanus (Rafinesque) – southeastern United States and inland to the Mississippi valley, up to southwestern Missouri and southern Illinois
- L. r. mohavensis (B.Anderson) – Mojave Desert of California
- L. r. baileyi (Merriam) – southwestern United States and northwestern Mexico
- L. r. superiorensis (Peterson & Downing) – western Great Lakes area, including upper Michigan, Wisconsin, southern Ontario and most of Minnesota
- L. r. californicus (Mearns) – California west of the Sierra Nevada
- L. r. oaxacensis (Goodwin) – Oaxaca
- L. r. fasciatus (Rafinesque) – Oregon, Washington west of the Cascade Range, northwestern California, and southwestern British Columbia
- L. r. escuinipae (J. A. Allen) – central Mexico, with a northern extension along the west coast to southern Sonora
- L. r. pallescens (Merriam) – northwestern United States and southern British Columbia, Alberta, and Saskatchewan
- L. r. peninsularis (Thomas) – Baja California
The division of subspecies has been disputed, given a lack of clear geographic breaks in their ranges and the minor differences between subspecies.
Distinctive stubby tail
Bobcats resemble other species of the mid-sized Lynx genus with a gray to brown coat, though generally tan to grayish-brown, with black streaks on the body. On an average it is smaller than the Canada lynx, with which it shares parts of its range. About twice as large as the domestic cat, this excellent climber has pointed, black-tipped and black-tufted ears, whiskered face and distinctive black bars on its forelegs and a black-tipped, stubby tail whose “bobbed” appearance gives the species its name. These cats are muscular in built and their hind legs are longer than the front ones, giving them a bobbing gait.
Bobcats are larger in their northern range and in open habitats. A morphological size comparison study in the eastern United States found a divergence in the location of the largest male and female specimens, suggesting differing selection constraints for the sexes. Their spotted coat provides excellent camouflage. The color of the coat changes with the habitat. For example in the desert regions of the southwest these cats have the lightest-colored coats, while those found in the northern, forested regions have the darkest coat. They usually have an off-white color on the chin, lips and underparts.
Bobcats have ruffs of extended hair beneath the ears, which makes the face of the cat appear wide. Their eyes are yellow with black pupils and the nose is pinkish-red. The cat has a base color of gray or yellowish or brownish-red on its face, sides, and back. It’s eyes are yellow with black pupils, which widen during nocturnal activity to maximize light reception. Bobcats have sharp vision and acute hearing, besides a good sense of smell. Whenever there is a need they swim well, but normally they avoid water.
A few melanistic cats have also been sighted and captured in Florida. Despite their black color their spot patterns are still visible.
Adult cats are 48 to 125 cm long from head to the base of the tail, averaging 82 cm; stubby tail adds 9 to 20 cm. Adults stand about 30 to 60 cm at shoulders and males can weigh from 6.5 to 18.5 kg, with an average of 9.5 kg; females are smaller and weigh 4 to 15 kg, with an average of 7 kg. There are unverified reports about bobcats reaching 27 kg, but the largest one which was accurately measured on record weighed 22.2 kg.
Bobcats with largest-bodies are found in eastern Canada and northern New England and they are from the subspecies (L. r. gigas), while the smallest ones are from the southeastern subspecies (L. r. floridanus), particularly those in the southern Appalachians, a system of mountains in eastern North America.
Bobcats are crepuscular (active primarily during twilight i.e. dawn and dusk) in habit. To forage they come out three hours before sunset and remain active until about midnight, and then again from before dawn until three hours after sunrise. During this period they cover 3.5 to 11 km of their habitual route each night. This behavior is not fixed it may vary seasonally and according to situations. They become more diurnal during fall and winter in response to the activity of their prey, which are more active during the day in colder months.
Social structure and home range
Like most felines, bobcats too are largely solitary animals. They remain active in well-defined, overlapping territories that vary in size depending on the gender and the availability of food. One thing which is unusual in the case of these cats is that males are more tolerant of overlap, while females rarely wander into others’ ranges. Wherever numerous male home ranges overlap, a dominance hierarchy is usually established, which results in the exclusion of some transients from favored areas. Female home ranges are smaller in size, therefore two or more females may reside within a male’s home range.
In line with widely differing estimates of territory sizes, population density figures are also divergent. According to one survey they range from one to 38 individuals per 26 sq km. The estimated average is one cat per 13 sq km. A link has been observed between population density and sex ratio. Two studies have come with similar observations. Out of these one noted a dense, unhunted population in California with a sex ratio of 2.1 males per female. When density declined, the sex ratio skewed to 0.86 males per female. While observing the similar ratio another study suggested the males may be better able to cope with the increased competition, and this would help limit reproduction until various factors lowered the density.
Home range sizes of bobcats vary significantly; a research summary by IUCN suggests ranges from 0.052 to 330 sq km. One study conducted in Kansas noted resident males to have ranges of roughly 21 sq km and females with less than half that area. Transient individuals were found to have both larger (roughly 57 sq km) and less well-defined territories. Kittens had the smallest range at about 7.8 sq km. Research has indicated that the dispersal from the natal range is most pronounced with males.
Reports on seasonal variation in range size have been equivocal. One found a large variation in male range sizes, from 41 sq km in summer up to 100 sq km in winter. According to another, female bobcats, especially those that were reproductively active, expanded their home range in winter, but that males merely shifted their range without expanding it, which was consistent with numerous earlier studies. Researches in different other American states have shown little or no seasonal variation.
Like many felines bobcats too mark their territories with urine scent, feces and by clawing prominent trees in the area. They are quite systematic in their life and keep numerous places of shelter in their territory. They include several auxiliary shelters on the outer extent of its range, such as brush piles, hollow logs, under rock ledges and thickets besides the main den, which smells strongly of the bobcat.
Hunting and diet
Bobcats are opportunistic predator. They are able to survive for long without food, but when food is available they would eat heavily.
Unlike Canadian lynx, the more specialized predator, bobcats will easily vary their prey selection, which positively correlates to a decline in numbers of their principal prey; the abundance of the main prey species is the main determinant of overall diet.
This feline hunts animals of different sizes. Usually its preference is for mammals weighing about 1 to 5.7 kg and they vary from region to region. In the eastern United States, it is the eastern cottontail species, while in the north it is the snowshoe hares. Where these prey species exist together, as in New England, they constitute the primary food sources of the cat. Its hunting strategy usually includes stalking the prey and then ambushing it with a short chase or pounce.
In the case of small prey, such as rodents, squirrels, birds etc. it will lie, stand or crouch and wait for the victim to come closer. It will then suddenly pounce and grab it with its sharp, retractable claws. For slightly larger animals, such as rabbits and hares, it will stalk from cover and wait until they are within 20 to 35 ft before rushing in to attack. It rarely feeds on larger animals, like young ungulates and other carnivores such as small dogs, foxes, skunks, minks and domestic cats. They are also notorious for killing domesticated species. Occasionally they go for livestock and poultry. In this segment they pose threat especially to smaller animals like sheep and goats. Records of the National Agricultural Staiistics Service show that bobcats are responsible for killing 11,100 sheep in 2004, comprising 4.9 per cent of all sheep predator deaths. Experts feel out of the above some of the sheep killings have been wrongly attributed to bobcats as they have been known to scavenge on the remains of livestock killed by other animals.
Usually it is during the lean periods, bobcats kill larger animals. Since it can not consume the victim in one sitting it buries the carcass under snow or leaves and returns to feed on later. They have been known to killing deer, especially in winter when cat’s main food source, smaller animals, become scarce or when deer populations become more abundant. According to a study conducted in the Everglades a large number of kills (33 of 39) were of fawns. To hunt a deer it stalks it, often when the ungulate is lying down, then rushes in and grabs it by the neck before biting the throat, base of the skull, or chest.
Reproduction and life cycle
Young bobcats start breeding usually by their second summer, though females may start as early as their first year. During courtship, the otherwise silent bobcat may let out various sounds that include loud screams and hisses, etc. Females have estrous cycle of 44 days, with the estrus lasting five to ten days.
During breeding season dominant males travel with their partners and mate several times in typical cat-like fashion — male grasps his mate in the felid neck grip and mates. Other males may be in attendance, but remain uninvolved. This happens generally from winter until early spring. This, however, varies by location, but most matings take place during February and March. The pair may undertake a number of different behaviors, including ambushing, bumping and chasing. Females may later go on to mate with other males, and males usually mate with several females.
Gestation period lasts for about 60 to 70 days, after which one to six, but usually two to four, kittens are born in April or May. Sometimes a second litter is born as late as September. After the successful mating female selects a secluded and secured place, which usually is a small cave, rock crevice or hollow log, to give birth to its offspring.
Males do not play any role in raising the young, it is only the mother who performs all the responsibilities alone. Kittens that are born blind, but well-furred and already have their spots, open their eyes by the ninth or tenth day. When they are four weeks old they start exploring their surroundings and are weaned at about two months. Within three to five months, they start traveling with their mother. By fall of their first year they start foraging for themselves and usually disperse shortly thereafter.
At birth, kittens weigh 270 to 340 g and are about 25 cm in length. By their first birthday, they attain about 4.5 kg weight. A Research in Texas has suggested that establishing a home range is necessary for breeding in these cats. Studied animals with no set range had no identified offspring.
Bobcats that remain reproductively active throughout their lives usually live up to six or eight years, with a few reaching beyond ten. The longest they have been known to live is 16 years in the wild and 32 years in captivity.
In addiction to man bobcats have few other predators too. Besides being killed in interspecific conflicts cougars and gray wolves also kill adult individuals. Killing of kittens by coyotes is very common, but there also instances where they have killed adult cats too.
Kittens are killed by several predators, including birds like owls and eagles, in addition to foxes and other adult male bobcats; especially when prey is scarce killing of kittens by predators increases and fewer of them are likely to reach adulthood. Golden Eagles (Aquila chrysaetos) have also been reportedly observed preying on adult bobcats.
Other causes of bobcat deaths include diseases, hunting, accidents and starvation. Juveniles also face high mortality rate, especially, after leaving their mothers. According to a study of 15 bobcats yearly survival rates for both sexes averaged 0.62, in line with other researches suggesting rates of 0.56 to 0.67.
Distribution and habitat
Bobcats can be found in various kinds of habitats, ranging from the desert lands of Texas to humid swamps of Florida or rugged mountain areas. It also makes its home near agricultural areas, if forested tracts or rocky ledges or swamps are present. Although it prefers woodlands—deciduous, coniferous or mixed—but unlike other Lynx species, it does not depend exclusively on the deep forests. Its spotted coat serves as camouflage.
The number of bobcats residing in an area depends on the availability of prey. Other factors in the selection of habitat type include availability of resting and den sites, freedom from disturbances, dense cover for hunting and escape and finally protection from severe weather. Bobcat ranges do not seem to be affected by the presence of humans, as long as the cat can find a suitable habitat. It can also be found in back yards in “urban edge” environments, where human development intersects with natural habitats. Only large, intensively cultivated tracts are unsuitable for the species.
As far as the historical range of the cat is concerned it was spread over from southern Canada, throughout the United States, and as far south as the Mexican state of Oaxaca. Even today it still persists across much of this area.
In Canada its population is limited due to both— presence of Canadian lynx and the snow depth. Bobcats are not comfortable in places where the snow is deep and will wait out heavy storms in sheltered areas. The reason is they lack large, padded feet of the Canadian lynx and are unable to support their weight on snow as efficiently. Despite this bobcats are not entirely at a disadvantage where their range meets that of the larger felid. Displacement of Canadian lynx by the aggressive bobcat has been observed where they interact in Nova Scotia, one of Canada’s three Maritime provinces, while the clearing of coniferous forests for agriculture has led to a northward retreat of the Canadian lynx’s range, which is to the advantage of the bobcat. In central and northern Mexico, the cat is found in dry scrubland and also in forests of pine and oak; its range ends at the tropical southern portion of the country.
Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) has listed bobcat in its Appendix II, which means the animal is not considered threatened with extinction, but hunting and trading must be closely monitored. The IUCN has placed it in the list of species of “least concern”, meaning it is relatively widespread and abundant.
The animal is regulated in all three of its range countries — Canada, Mexico and USA. According to the estimates of US Fish and Wildlife Service the bobcat population was between 700,000 and 1,500,000 in 1988 in the US, which is its principal territory. Increase in the range and population density suggested even greater numbers in subsequent years; for these reasons, the U.S. had petitioned CITES to remove the cat from Appendix II. Despite the over all large number of the animal there are still some states, like Ohio, Indiana and New Jersey, where the species is still considered endangered. In 1999 it was removed from the threatened list of Illinois and that of Iowa in 2003. In Pennsylvania, limited trapping and hunting are once again allowed, after having been banned from 1970 to 1999. At the turn of the 19th century the cat had faced population declines in New Jersey, mainly due to commercial and agricultural developments that caused habitat fragmentation. By 1972, the cat was given full protection and was listed as endangered in the state in 1991.
Populations in Canada and Mexico also remained stable and healthy, but information from southern Mexico is poor. L. r. escuinipae, the subspecies found in Mexico, was for a time considered endangered by the US Fish and Wildlife Service, but was delisted in 2005.
These animals have long been valued both for their fur and sport; they have been hunted and trapped by humans, but still they maintained a high population. In 1970s and 1980s, there was large scale hunting of these cats due to an unprecedented rise in the price of their fur, but by the early 1990s, prices had dropped significantly. Since regulated hunting still continues, most of the bobcat deaths are reported in winter when hunting season is generally open.
Large scale urbanization has resulted in fragmentation of the natural landscapes into patchy habitat in and around urban areas. Bobcats along with the other animals that inhabit these fragmented areas face the problem of reduced movement between the habitat patches. This poses the problem of reduced gene flow and pathogen transmission between the animals residing in various patches. Since bobcats are accustomed to large home ranges, they are particularly sensitive to fragmentation. A study conducted in the coastal areas of Southern California has shown that creation of roads and other developmental activities has affected the bobcat populations adversely.
Experts are of the opinion that bobcats though adapt to a wide variety of habitat conditions, loss of habitat to urbanization and fragmentation is the only significant threat to current populations.
Utilization and Trade
In 38 states of U.S. and in the regions of Canada and Mexico, Bobcats are legally harvested. Although this activity increased during 1976-1984, recent harvest levels in the U.S. have been comparable to those observed prior to CITES listing (34,937 harvested during 1995-1996 versus 35,937 harvested during 1975-1976).
Between 1998 and 2002, there was a export of 118,929 specimens to various places, according to the data available with World Conservation Monitoring Center (WCMC). Of this majority of the export originated from range countries. However, only 9 specimens originated from Mexico.
According to U.S. Fish and Wildlife Service Law Enforcement databases 174 Lynx rufus specimens were seized by law enforcement agents between 1998 and 2004.
It was not only the native Americans, but even the European settlers who came to the Americas also admired the cat, both for its ferocity and the grace, and in the United States, it “rests prominently in the anthology of … national folklore.”
Shawnee tale (Shawnee or Shawnee nation are an Algonquian-speaking people native to North America) mentions about the bobcat that was outwitted by a rabbit, which gives rise to its spots. After trapping the rabbit in a tree, the bobcat is persuaded to build a fire, only to have the embers scattered on its fur, leaving it singed with dark brown spots. The Mohave (Mohave or Mojave are Native American people indigenous to the Colorado River in the Mojave Desert) believed dreaming habitually of beings or objects would afford them their characteristics as supernatural powers. Dreaming of two deities, lynx and cougar, they thought, would grant them the superior hunting skills of other tribes.
Bobcats are often paired with coyote in a theme of duality in Native American mythology. Coyote and Lynx are associated with the wind and fog, respectively—two elements symbolizing opposites in Amerindian folklore. The basic story associated with this is found in the native cultures throughout the North America (with parallels in South America) in many variations, but they vary in the telling.
One version, which appears in the Nez Perce folklore (Native Americans who live in the Pacific Northwest region, more specifically Columbia River Plateau, of the United States) for instance, portrays lynx and coyote as opposed, adversative beings. However, another version shows them with equality and identicality. Claude Lévi-Strauss claims the former notion, that of twins representing opposites, is an inherent theme in New World mythologies, but they are not equally balanced figures, representing an open-ended dualism rather than the symmetric duality of Old World cultures. The latter concept then, Lévi-Strauss suggests, is the result of regular contact between Europeans and native cultures.