Black Bear: Ursus americanus floridanus
The Florida black bear (Ursus americanus floridanus), is one of 16 subspecies of the American black bear.
Black bears originated in North America at least 1.5 million years ago.
Scientists assign all living organisms a Latin name, also called the binomial name. Using Latin avoids confusion caused when people from different places, speaking different languages, use different names to talk about the same animal or the same name to talk about different animals. For example some people callCathartes auraturkey vultures, while others call them buzzards. The process of organizing organisms into groups (taxons) by shared characteristics is called "taxonomy". These taxonomic groups work by starting with the most general characteristics and working down to very specific traits, and reflect how creatures are related through evolution.
The complete "taxonomic tree" for the Florida black bear is:
Kingdom: Animalia (animals, not plants or single celled organisms)
Phylum: Chordata (have spinal chords)
Sub-phylum: Vertebrata (have a back bone)
Class: Mammalia (mammals)
Order: Carnivora (classified by body structure as carnivores)
Family: Ursidae (Latin for bear family)
Genus: Ursus (Latin for bear)
Species: americanus (from America)
Subspecies: Floridanus (from Florida)
Bears can be found just about anywhere in Florida. Currently, there are more than 3,000 bears statewide. Researchers are working to update the population estimates in phases. It is anticipated all analyses will be completed as early as the summer of 2016. Learn more about where bears can be found.
Like all members of the bear family, black bears are large, powerful mammals with rounded ears, short tails, 5-toed feet, and large canine teeth.
Black bears may look slow because they walk flat on their feet (called plantigrade) like people, and travel with a shuffling gait, but they can sprint up to 30 miles an hour. Olympic gold-medalist Usain Bolt can onlyreach 27 mph.
With their stout, heavily-curved claws, black bears climb trees very well. Their claws are non-retractable and can be easily seen in their tracks.
Although black bears in other parts of North America may have several color phases, such as cinnamon, blonde, or even white, all black bears in the Southeast, including Florida black bears, are black.
The muzzle, or snout, may be tan or nearly black and blonde or white chest blazes of all shapes and sizes are common.
Most people find it hard to estimate the size of a bear they have seen in the wild. One good method is to pay attention to the relative size of their ears. The ears of black bears reach full length when they are juveniles, so small, skinny juveniles appear to have very long "Mickey Mouse" ears on slender faces, while large, adult males seem to have very small, rounded ears on wide, round heads. Also, adult males tend to have wide, wedge shaped faces, while females have more slender looking faces.
Additionally, bears are sexually dimorphic. For bears this phrase means that adult males are generally twice the size of adult females.
Many of us recognize that white-tailed deer body size is reduced as you travel south in North America. This difference is explained by Bergmann’s Rule, which basically states species of larger size are found in colder environments, and species of smaller size are found in warmer regions. Bears as a Family follow this principle – arctic male polar bears generally weigh 779 to 1500 pounds, while male sun bears only weigh 100 to 140 pounds and live in equatorial regions. Black bears as a species do not follow Bergmann’s Rule, Florida black bears on average tend to be larger than Canadian black bears, for example. Adult males in Florida normally weigh between 250 - 450 pounds, with adult females weighing between 125 - 250 pounds.
- There have been two male bears that are considered the largest in the state. One was a 740 lb bear and the other was 760 lb bear, both were found in 2015 in Seminole County lingering in neighborhoods after gaining access to unsecured human-provided attractants.
- The largest female bear found in Florida was 400 pounds, found on the side of a road (killed by a vehicle strike) in January 2007 in Liberty County.
The weight of individual black bears varies greatly throughout the year, more on that phenomenon in the diet section.
Vision: Black bears are believed to see in color and have great up close eyesight. Recent research is showing that their long distance eyesight is not very good, they are likely not able to see details of a large objects from further than 30 yards away.
Hearing: They have acute hearing that is about twice as sensitive as humans and over a large frequency range as well.
Smelling: They have an excellent sense of smell (black bears can smell over than a mile away!). That is more than seven times better than a bloodhound. Bears, as a Family, are considered to have the best sense of smell of any land mammal.
Swimming: Bears are excellent swimmers and will frequent nearby islands during seasonal changes in food availability.
Sounds: Bears are quiet creatures, but occasionally they make sounds to communicate.
Black bears prefer habitats with a dense understory such as forested wetlands and uplands, natural pinelands, hammocks, scrub, and shrub lands. Black bears are considered an umbrella species – a wide ranging species whose protection (and habitat’s protection) in turn protects numerous other species.
Bears are omnivores because they eat both plant and animal matter. A bear's diet consists of 80% plant material, 16% insects, and 4% animal matter.
The vegetative part of their diet is made up of grasses and leaves, as well as mast. Hard mast is the fruit of forest trees like acorns, hickory and other nuts, while soft mast is fruits such as saw palmetto, holly, and pokeweed berries. They also feed on colonial insects such as wasps, bees, termites, and ants. The small meat portion of their diet is things that are dead (carrion) or play dead (e.g. armadillos, opossums).
The black bear diet varies seasonally and yearly depending on fluctuations in plant productivity. Saw palmetto berries are a large part of a bear’s diet throughout Florida.
A bear’s ability to find and eat a wide variety of food types can bring bears into contact with humans, where they take advantage of unsecured garbage, barbeque grills, wildlife feeders, beeyards, etc. Learn more about how you can live safely in bear country.
During the summer months, bears eat about 5,000 calories a day or the equivalent of two large cheese pizzas. But as fall begins bears start preparing for winter by going through a process of increased feeding called "hyperphagia”. Both sexes will forage up to 18 hours a day and gain up to 1½ times their summer weight. This weight gain is because they are taking in up to 20,000 calories a day or the equivalent of 8½ large cheese pizzas. Another way to look at it is 20,000 calories is what the average person eats in 10 days! Gaining weight allows bears to make it through the leaner winter months, where both male and female bears will lose weight due to the lack of food items. Once freezing temperatures set in bears will begin denning. Florida dens are usually made of dead plant material in dense thickets. Bears can lose up to 25% of their body weight while denning.
Bears that habitually feed on human supplied foods such as garbage, wildlife feed, or pet food tend to be abnormally large.
Male bears, may stay active and eating all winter. Females need to be in good condition to produce and feed cubs during denning.
Bears are solitary by nature, except when in family groups or pairings during the mating season.
Bears will congregate in areas of high food density, such as oak stands or berry patches. These groupings happen because one bear cannot defend such a rich food source from competitors.
While bears may defend a food resource while they are consuming the item, in general, bears are not territorial, in that they do not defend a specific area from intrusion by other bears. The area they inhabit in search of food, water, and adequate cover is called a home range.
- Individual bear home ranges may overlap.
- The size of a home range may vary each season and year depending on the sex, age, and reproductive status of the bear, bear population density, and food availability.
- During major droughts and mast failures, bears will explore new areas in search of food.
- Black bear are curious animals. They often do a lot of sniffing and may stand up on hind legs to get a better view and smell of their surroundings. This is normal non-threatening behavior and is generally not a sign of aggression. Bears respond to people as they would other bears. Understanding the various responses and ways bears communicate can help people to coexist with bears.
- When bears are uncomfortable in a situation, they may act in a defensive manner by, huffing or blowing air from their nose, and popping their jaws together.
An aggressive bear does not growl like a dog. Instead, they will stare, protrude their lower lip, stomp the ground, and flatten their ears. Black bears bite and claw on trees between 5 and 7 feet high on the trunk of both conifers and hardwoods, but the reasons for such markings is not fully understood. Many scientists believe the markings occur to establish hierarchies. Most likely there are several reasons why black bears mark trees. Marks occur along defined game trails, with the mark facing the trail. Often bears rub against these trees as well.
Black bears do not hibernate, instead they experience what is often called 'ursid hibernation' or 'carnivore lethargy'.
This period of reduced activity occurs in all black bear populations because winter lethargy is an adaptation to the lack of available food, low temperatures, and light conditions.
Bears in southern states, from North Carolina south to Louisiana, den for shorter periods and sleep less deeply than bears in colder climates.
While denned bears in northern states are very lethargic and less responsive to people, bears in the South readily run away when people come close to their den.
In Florida, males and non-pregnant females may den up in dense vegetation for only a few weeks or a month if the weather is cold enough.
Pregnant females will den up for the entire winter, and because their cubs will be born in the den, they often select more protected sites.
Dens may be in tree cavities, under blow-downs or fallen logs, or ground 'nests' in dense thickets.
The breeding season for black bears runs from June to early August, but cubs are not born until late January to early February of the following year.
Bears reproduction is somewhat unique and called delayed implantation. The egg is fertilized in the summer but does not implant in the uterine wall until mid-November or early December. The fetus will grow until birth in about 8-12 weeks.
If the female is in poor body condition and nutritionally stressed, the fertilized egg may be reabsorbed, the partially developed fetus will not develop further or cubs will be miscarried and eaten by the female.
The body condition of a female is what dictates how many cubs she will give birth to – the better the body condition, the more cubs in her litter.
This adaptation to periodic food shortages prevents the female from producing offspring for which she cannot care.
Bear cubs are very small at birth, only 225 – 450 grams (8 – 15 ounces) and the size of a small squirrel.
They have a very fine coat of hair, they are not mobile, and their eyes are closed. Litters range from 1 to 5 cubs, but 2 or 3 are most common in Florida.
The cubs nurse and play in the den until emerging with their mother, typically in April.
Over the next year cubs will stay with their mother learning how to be a bear, and will usually den with her the following winter.
During a cub’s second spring, the family group breaks up, the juveniles wander off on their own, and the adult female is ready to breed again.
Female yearlings will likely establish their home ranges near or overlapping their mothers, while male yearlings will find new areas to establish home ranges.
Taking care of the cubs for this period of time means that adult females will typically only breed every other year.
Life Expectancy and Mortality
Bears normally live between 10 to 20 years in the wild.
The 2 oldest known bears from Florida were both 20 years old – a male caught in 2008 in Marion County and a female killed in 1985 during a legal bear hunt held on Apalachicola Wildlife Management Area.
In zoos, black bears have been known to live into their 30's. Adult black bears have no predators besides humans and other bears, but do suffer mortality from other sources such as vehicle strike related mortality.
Cubs: Approximately 25-50% of all cubs die before they turn one year old. Natural causes of death include drowning, den cave-ins, hypothermia due to flooded dens, starvation, infections from injuries, and predation (by other bears). They are also struck by vehicles.
Juveniles: Yearlings will establish their own home range once they disperse from their mother. Yearlings are susceptible to high mortality rates as a result of starvation, predation by other bears, and vehicle collisions. About a quarter will die before they turn two years old.
- Young, independent females establish a home range close to their mother. About 20% die before reaching adulthood (~4 years old).
- Juvenile males travel farther in search of a new home range. The traveling needed to forage and find new den sites in unknown territory increases mortality risks, and approximately 46% of males will die before reaching adulthood.
Adults: Once fully grown, black bears have no predators besides humans and other bears. The main cause of mortality in Florida is vehicle collisions. Other causes include starvation, poaching, other bears, disease, and accidents.
Hunting: In June 2015, the FWC Commissioners approved a limited bear hunt to take place in October 2015 in four of the seven BMUs . As outlined in the article by FWC Director Nick Wiley, the hunt is a tool being used to stabilize bear subpopulation numbers.
A total of 304 bears were taken during the hunt. To learn more about the full details of the hunt, please review the summary document and spreadsheet of all data collected on harvested bears.
Disease and Parasites
Little information is available on the diseases and parasites of wild black bears. Research shows that, while bears host external parasites (ticks and mites) and several types of internal parasites (helminths, nematodes, trematodes, and acanthocephalams); these creatures are not believed to cause any significant health problems to bears.
Additional Information about Florida’s largest land mammal, the Florida black bear, is available at MyFWC.com/bear.
Image Credit: M Orlando