Scientific Name:              Didelphis virginiana

Common Name(s):          Virginia Opossum, Possum

Identification:

Virginia opossums Didelphis virginiana are the only marsupial (mammals with a pouch) in North America. They are small to medium in size and have mixed black, gray, and white fur. Their faces are white with a long pink nose, black eyes, and black ears. They have opposable thumbs on their hind legs which help them climb trees. The hind legs also do not have claws. Their tail is prehensile, meaning it can grab and hold things, and is used mainly for gripping limbs when in trees. A common misconception about opossums is that they hang from their tails to sleep. Although they can hang from their tails for a short time, it is not strong enough to hold them for that long. Males often weigh more and have larger teeth than females, while females have a marsupium (pouch) to hold babies. Opossums range from 10-40 inches in length, without tail, and weigh up to 8 lbs. for females and up to 14 lbs. for males.

Fun Facts:

These animals display characteristics that are very unusual for North American mammals.  Among them are…

1. Opossums are the only North American marsupial (development of young in a pouch)
2. They have 13 nipples in a circular arrangement with one in the middle.
3. Their brain is 1/5 the size of a raccoon of similar size.
4. They have 50 teeth. More than any other North American Mammal
5. They have a prehensile (grasping) tail.
6. They have opposable thumbs on the hind legs
7. No claws on hind legs
8. Yes, they do play possum
9. From an evolutionary standpoint they are not “living fossils” as they evolved recently (20 million years ago)
10. Extreme example of Bergman’s Rule which states that individuals within a species are larger in colder climates to conserve heat.  Northern opossums are up to 20 times larger than their southern cousins.

Scientific Name: Carya (Genus)
Common Name(s): River Otter, North American River Otter

Identification:
River otters live in and around water. They have long streamlined bodies with a long, tapered tail. Otters have oily brown fur all over their body, including their tail; this can help distinguish them from the beaver with its hairless tail. The fur on their underside is typically a lighter brown or gray. Otters also have long prominent whiskers. Their feet are webbed, and their hands are very dexterous. Otters weigh 10-30 lbs., with males larger than females, and are 24-42 inches in length.

Range:
Otters were natively found throughout North America, from Alaska and Canada to the Gulf of Mexico, and from coast-to-coast. However, habitat destruction, urbanization, and pollution have extirpated the river otter from some states in the U.S.

Ecology:
River otters inhabit more than just rivers. They can be found in inland freshwaters, such as rivers and lakes, and in marine and brackish waters. They prefer waters with adjacent woodlands but can survive in any location with a steady supply of food and access to a waterbody. Otters live in dens built in a natural hollow, an undercut riverbank, hollow log, or in the burrows of other animals. The entrance may be under water or above ground. The den is typically lined with leaves, grass, bark, and moss.

Otters are typically ambush predators, lunging and grabbing prey, rather than pursuing prey. They are well adapted for hunting in water: they can stay submerged for up to 4 minutes, swim at a speed of nearly 7 mph, and dive to a depth of 65 ft. While their primary diet is fish and crayfish, they will opportunistically eat anything, including fruit, reptiles, amphibians, birds, insects, and small mammals. They will avoid carrion.

Reproduction is viable at two years of age, and males usually mate with multiple females. Breeding occurs from December to April. While gestation lasts two months, otters delay implantation for up to eight months, meaning that birth usually occurs 10-12 months after copulation. Litters usually consist of one to three pups, rarely up to five. Pups are born fully furred but are blind and toothless. They open their eyes at four weeks, consume solid food at nine weeks, wean at 12 weeks, and are provided food up until 38 weeks. While they can sustain themselves at an earlier age, pups usually stay with their family until the following spring and leave before a new litter is born.

Special Notes:
Here in Bella Vista, otters are uncommon. Little Sugar Creek provides a corridor for otters to get to Bella Vista and potentially all our lakes. In January 2020, an otter was seen eating fish in the Avalon heated dock multiple times. The Lakes and Parks staff may take measures to relocate the otter to prevent interference with the fish hatchery program. Although they are fascinating to watch, otters can be voracious and wreak havoc on a contained system like in a fish hatchery.

A curious otter at the Avalon Heated Fishing Dock.
Photo courtesy of Tom Vickery

Featured Image: https://tinyurl.com/qr2vock © Charles Kennard

Scientific Name:              Odocoileus virginianus

Common Name(s):          White-tailed Deer, Whitetail

Identification:
White-tailed deer, Odocoileus virginianus, are most recognizable by the bold, white underside of their tails, which stands up straight when alarmed. In the summer adult deer have a thin reddish coat but is replaced with a thick brown coat around September. They have white on their undersides, insides of their ears, and beginning of their necks. Their ears are lined with darker fur, and there is white around their noses and mouths. Their hooves are separated into two parts with a split down the middle. Males, or bucks, have antlers that are shed and re-grown each year. Females are known as does, and young as fawns. Fawns are characterized by the white spots all over their body which they lose by 6 months of age. Bucks average 100 lbs., with does around 88 lbs., but weights are highly variable. In the northern parts of their range, deer are bigger in size.

Range:
Odocoileus virginianus is native to the United States, with a range including southern Canada down to northern South America. They have been introduced to other parts of the world such as Puerto Rico, New Zealand, and Cuba.

Ecology:
White-tailed deer prefer habitats with forest edges and open woodlands. They also like areas with dense vegetation for protection from predators. White-tailed deer are herbivores, consuming plants, grasses, fruits, acorns, clover, and corn. Deer can be considered a nuisance to farmers who grow corn or fruits that the deer will feed on and cause damage. In places with large populations of deer, they can have major impacts on native plants, although their browsing can help plant diversity in some areas. A deer’s home range usually consists of around one square mile, but this area is not in any defined shape, rather it is based on habitat, terrain, and home ranges of dominant deer. Deer can jump high fences and have a propensity to be a hazard on roadways.

Deer have many different calls they use to communicate with each other. Fawns will squeal, called bleat, if they have been separated from their mothers which will deepen as it matures. Adult deer grunt to each other to get attention, or a mother will grunt to find her fawn. When they feel threatened, deer will snort or blow to signal danger to other deer in the area and will raise their white tail while running away.

White-tailed deer in Arkansas breed from October through December with the peak usually occurring in mid-November. Breeding season is known as the rut. Males will breed with as many females as they can. Bucks will scrape an area with their hooves, clearing some ground and rub their antlers on the bark of a small tree to let females know that a male is in the area. They will urinate in these areas to leave their scent. Males may also fight with their antlers and hooves during territory or breeding disputes. Females release hormones and pheromones when they are in heat, letting bucks know they can breed. Females are pregnant for 6.5-7 months before giving birth. Females will nurse the fawns and hide them in dense vegetation for around 4 weeks to keep them hidden from predators. After that, fawns can get up and follow their mothers to search for food. Male fawns normally leave their mothers after a year, while females tend to stay longer.

Chronic wasting disease (CWD), a fatal neurological disease with no cure, has been found in some deer in Arkansas. It is caused by a protein in the brain that is abnormally shaped, called a prion. This disease can spread from direct contact between animals, or through contaminated plants. This disease causes deer to slowly waste away and become very sick. Humans are not at risk of getting CWD, although it is suggested that you should not eat a deer that has the symptoms of CWD. Also, there are some tick-borne diseases that deer are an intermediate host for, such as Lyme disease and Rocky Mountain spotted fever, which can be transmitted to humans.

Deer are popular among hunters for their meat, called venison, and for the antlers of bucks. Bucks will grow their first set of antlers when they are a year-old during spring and summer. Antlers are pure bone, although when first starting to grow, they are covered with blood vessels, nerves, and a soft layer called velvet. Growth can continue until September when the deer will start to rub off the velvet layer on trees or anything hard. Once the velvet falls off, the hard bone is left. Their antlers are shed around January-February.

Special Notes:
Here in Bella Vista, white-tailed deer can be seen virtually anywhere at any time. They are most active at dawn and dusk. Be careful of deer by roadways as they often run out in front of traffic. The second or third deer is often determined to follow the leader and often collisions with cars come from “the followers”.