These two mammals have adapted to urban environments

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Many wild mammals tend to live secret lives and are rarely seen, but there are always exceptions in nature. Several species have learned to live well around humans, resulting in increased populations and expanded ranges throughout our region and Texas and Oklahoma. In fact, two types of medium-sized omnivorous (eating both plants and animals) mammals are familiar to most of us and are often seen during crepuscular hours and at night.

virginia opossum

The first of these widespread mammals we will discuss is the Virginia opossum. Many people may not have a very good idea of ​​”possums” (as they are commonly known), but this versatile and successful animal is the only native animal found in the United States. They are marsupials and were once hunted for their fur and meat. Historically, the Virginia opossum was the third most hunted fur-bearing animal in Texas. The adult Virginia opossum is about the same size as a small terrier dog and has an unmistakable appearance. Their fur is long, generally gray to white, with fairly short, rounded tips and black, leathery ears. The fur at the base of the tail and on the legs is black. The Virginia opossum’s distinguishing feature is its long, scaly, naked, prehensile tail. This tail is used very effectively by opossums when climbing tree branches, climbing over and over fences, and moving over buildings and other structures. The feet have five toes. = The front feet look a lot like small hands (with opposable thumbs) and the hind feet also have opposable thumbs, all of which also help with climbing. The head and face are usually white, and the nose is long and pointed.

Virginia opossums are found in the region’s forests, mesquite meadows, riparian habitats along streams and rivers, grasslands and agricultural areas, as well as parks, walking and biking trails, and other habitats within cities and towns. It lives. Opossums are nocturnal foragers that eat a variety of foods. Food includes insects, earthworms, rodents, ground-nesting birds and bird eggs, amphibians, small reptiles, and snakes. The opossum’s diet also includes a variety of nuts and fruits, grasses, seeds, tubers, and other plant and vegetable matter. Although opossums’ reputation for killing poultry may be somewhat exaggerated, they are known to take waterfowl and small ground-nesting birds. Opossums do not hibernate and are active year-round. During very cold weather, Virginia opossums survive on stored body fat and live in tree cavities, brush piles, pre-excavated burrows in the ground of other animals, under buildings and other structures, and /or may remain in underground burrows. attic or loft.

On a personal note, I have been woken up several times by commotion between opossums and our farm cats and dogs, when opossums tried to attack our cat and dog food bowls. I remember. No fatalities were observed among combatants. However, I have seen opossums display their famous habit of “playing dead” to end conflicts. This particular survival behavior appears to have been effective, as the opossums were always “missing” the next morning. Opossums make loud noises and open their mouths whenever they feel threatened. However, they are generally shy and timid animals, and usually only bite as a last defense. As a less useful survival behavior, Virginia opossums have a habit of freezing in place when exposed to light. This behavior has resulted in many animals being hit by vehicles when opossums attempt to cross roadways.

One of the most unusual characteristics of the Virginia opossum is its reproduction and development. The reproductive season of the Virginia opossum lasts from January to July, and from winter to late spring it gives birth to 6 to 9 pups twice. Unique among North American mammals, the Virginia opossum has bifurcated reproductive parts, both male and female. Also, like many relatives of Australian marsupials, the female carries her newborn babies in a pouch (called a pouch) on her abdomen. marsupial) About 60 days after birth! Young opossums are very underdeveloped at birth. However, they can crawl into their mother’s pouch, attach to one of her mother’s nipples, and suckle to complete their early development and growth. After emerging from the pouch, young opossums are carried “on piggyback” by their mother until they are able to forage independently. Opossums don’t have a long lifespan (2-3 years) and have many natural enemies, including coyotes, dogs, bobcats, owls, hawks, and large snakes. Conversely, Virginia opossums appear to have developed some immunity to pit viper venom and are also somewhat resistant to rabies virus.

northern raccoon

Another acrobatic climber often seen in our area is the northern raccoon. These familiar mammals are slightly larger than the aforementioned Virginia opossum and have a more robust build with long gray fur that ranges from gray to almost black and is tinged with red on the neck area. His two unmistakable features of the northern raccoon are a black facial mask and a ringed tail with alternating bands of black and tan (sometimes white or gray) ending in a black tip. All paws have her five toes, and the front paws are specialized and skilled at grasping objects and manipulating food. The ears are relatively short and rounded, black to dark gray in color, with white margins. A large adult can weigh nearly 30 pounds, and up to 50% of their weight can come from accumulated body fat.

Northern raccoons are highly successful habitat generalists, living in a wide range of habitats including farmland, forests, riparian habitats, grassland edges, urban parks and playgrounds, walking and biking trails, urban garbage dumps, and many other locations. Their habitat is found throughout this region. Water available. Dead and hollow trees, brush piles, rock ledges, abandoned barns, buildings, and even attics are used as dens. Raccoons are excellent tree climbers and swimmers, and can escape potential predators by running away. When raccoons are heavily pressured by a predator, they usually swim away by finding a suitable tree to climb or jumping into a nearby pond, stream, river, or lake. Although not usually aggressive, cornered raccoons or mothers with young may choose to defend their position and fight. Predators of the northern raccoon include bobcats, coyotes, owls, and humans (raccoons are the most economically important furbearer in Texas).

Raccoons are nocturnal foragers and opportunistic omnivores with a very broad diet that includes many types of animals and plants. Raccoons are highly selective when food resources are abundant, and less selective when food is scarce. The diet includes insects, crayfish, mussels, small fish, bird eggs, carrion, seasonal fruits and nuts (such as prickly pear), and a variety of grains. Personally, I remember an example where a raccoon climbed into an open grain bin and settled down to eat a meal of wheat. Raccoons are well-adapted to urban environments and are notorious for raiding trash cans and garbage cans. Raccoons are known to move quickly and in straight lines between their burrows and their preferred foraging areas, and this allows raccoons to explore and learn their home areas and adapt to changing conditions and environments. It shows what you are doing.

The breeding season for northern raccoons lasts from February to June, with each litter producing three to seven young raccoons called cubs. Male raccoons are polygynous and expand their range during the breeding season, but after mating, the mother raccoon is solely responsible for raising her offspring. The cubs stay in their den for about 70 days to nurse, and go out with their mother for the first time within about three months. As young people grow up, they become more independent. However, the siblings and their mother may still dig and feed together for a while. Raccoons remain in their dens for long periods of time, even in extremely cold climates, relying on stored body fat for nutrition and warmth.

Although opossums and raccoons are both nocturnal, the chances of seeing them are still excellent because they live in a variety of habitats and are well adapted to urban life. Just remember to keep your trash cans and garages securely closed, and if not, enjoy the show. These two funny acrobats of hers are funny performers under the right circumstances.

Jim Goetze is a former biology professor and former dean of the College of Natural Sciences at Laredo University with a passionate interest in all aspects of the natural world.. He can be contacted at: gonorthtxnature@gmail.com



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