“Water Weasels!”

Cute as a furry button, but feisty and aggressive as a hungry or perturbed bobcat, diminutive Minks, although seldom seen are quite prevalent in North Carolina. Every county has a mink presence, but they are so secretive, solitary and territorial that hardly anyone knows they’re there. They run everybody off, even other minks. So, there’s never a huge population in any one place. Minks need to be near waterways and wetlands, so Eastern North Carolina is perfect habitat for these commonly called “Water Weasels,” but they can be found in the mountains and Piedmont regions of our state, too. Our coastal minks run smaller than those in the western part of the state. It’s a very rare occasion, but an infant Mink was brought to the Outer Banks Wildlife Shelter in Newport after being found alone and in a Pamlico County resident’s driveway. After a full examination, a puncture wound was found that looked ‘talon-esque.’ One theory suggests he was grabbed by a nocturnal raptor, possibly a Great-Horned Owl, and miraculously, he wriggled free and fell to the ground. Initially, the tiny furry find in the gravel was thought to be an otter, probably because we expect to see otters in our area and often do. Our tiny Mink, who is known to be semi-aquatic, feeds on minnow-sized fish, turtles, snakes, small birds, crayfish, reptiles, crustaceans, insects, rabbits, mice and other small mammals. So, you may have guessed by now; the mink is a carnivore. Minks are often thought of as dainty looking but extremely vicious because of their capability to kill prey much larger than itself, and even though that may be way too much to eat all at one time, they are not wasteful. They take the leftovers to their den for munching later. The mink is a small mammal with a long, thin body and short, sturdy legs, a flattened head, small eyes and ears, and a pointed nose. Each foot has five toes with claws and slight webbing between each toe. The mink’s lustrous waterproof fur is generally chocolate brown to black, extremely attractive and often sports a white patch on the chin or chest. Long, furred tails are brown at the base tapering to black at the tip. The American male weighs about 2.2 pounds, and the American female weighs about 1.32 lb. Minks have excellent senses of vision, smell and hearing. They are mostly nocturnal but can be occasionally seen during the day. They are as fast if not faster than any Olympic swimmer and can also climb trees. Minks are very vocal, especially when threatened, and will growl, hiss, screech or sometimes purr when perceived as happy or content. Another method of communication is to discharge a strong, musky, foul scent from their anal glands. If they are taking a skunk’s lead, something tells this author that they are not happy when they do that! Prime locations in wetlands for mink include areas with irregular shorelines, dense emergent vegetation, availability of den sites and a variety of suitable food. Although mink will den just about anywhere, they prefer burrows made by other animals, usually muskrats or beavers. They may also choose dens in brush piles, log jams or cavities in the roots of trees. Mink move frequently and adopt temporary dens except when they are rearing young. Most minks are loners and typically come together only to breed. The breeding season occurs from late January through February. Females raise their first litter at one year of age. Minks fall into the category of over 100 mammal species in which the fertilized egg is not implanted in the womb for some time. In mink, this period of delayed implantation lasts 10-40 days and is followed by an active pregnancy of 28-30 days. One litter of 4-5 blind and hairless kits is produced each year. Kits are weaned at 6 to 10 weeks, though how long they stay with their mother depends on the species; American or European. American mink youngsters stay with their Moms longer, 6–10 months, while European kits, only 4 months. The offspring are sexually mature when one year old, and females produce litters after their first breeding season. Though they are not endangered and are common throughout their widespread range across the United States (except for Arizona and Hawaii where they are nonexistent), a mink’s lifestyle is so inaccessible, they have not been intensely studied. But we do know that minks live three to four years, with a maximum record of 10 years. Aside from humans, mink have few natural enemies, although they experience danger and some mortality from domestic dogs, bobcats, foxes, coyotes and owls. Minks need wetlands to survive, so wetlands availability is the primary influence on mink populations. Some biologists believe that mink numbers have declined though, largely because of the steady destruction of prime mink habitat in wetlands. As a predator, minks are near the top of the aquatic food chain, making them susceptible to contamination in the food chain. Elevated mercury concentrations have been found in mink kidneys. It has been suggested that mercury can cause sublethal effects on many physiological functions, such as reproduction, growth and behavior. These studies are stated as inconclusive however, so further studies are recommended to investigate if there is a strong link between presence of environmental contaminants in mink and mink populations. Biologists acknowledge that other factors affect mink populations more gravely, such as habitat loss due to increasing development along eastern shorelines which alters both mink activity and prey abundance. Most important to the future of the mink in North Carolina is the conservation of wetlands, for their future is only as promising as that of the wetlands. Swim on, Little Water Weasel! We were happy to be of service to you!

Best Always,

Linda Bergman-Althouse

author of “Save Them All

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“Beaver’s Little Brother”

A little ‘brother of the beaver’ came into the shelter recently. He was tiny (only eight ounces), needy and fully self-aware that he required help. That’s exactly why a caring human managed to get his hands on a young Muskrat found wandering along the road in Newport. Fearing the infant musky would run into the road, the gentleman pulled his car over and proceeded to walk towards the little one to shoo him away from oncoming traffic, and how the gentleman saw the diminutive ‘eight-ouncer’ in the first place is remarkable. Rather than run away from the good Samaritan, which is normal avoidance behavior in the wild, the infant muskrat literally ran toward him. So, the caring rescuer picked him up, which is what we do with babies who are in distress, human or otherwise. The young Muskrat was alone, confused, scared and hungry. The youngster then took a ride to the Outer Banks Wildlife Shelter. A muskrat is more accurately a ‘cousin’ to the beaver, but “little brothers of the beaver” is what Native Americans named them many years ago. There is a definite resemblance between the beaver and the muskrat, but the muskrat’s long, skinny and nearly hairless tail rather than the ‘paddle’ tail, gives it away! Like a beaver, dark brown muskrats have a pair of musk glands they use to send messages to other muskrats and different species of animals as well. Of course, the “rat” part of their name refers to that long, skinny tail. Our little musky is doing well at the shelter; enjoying his mega amounts of formula (he’s still of nursing age), toying with some solids like vegetables and mud minnows and relishing his swim time in the deep sink. We are currently checking the wildlife rehabilitation communities in our state for another lone muskrat that could join him. They rehab much better in pairs, and we don’t want this little one imprinting on humans. If we allow him to bond with us, his chances of survival in the wild will be nil. Aquatic muskrats are a North Carolina indigenous species, however, the shelter does not admit them often. Muskrats are easier to keep wild than most wildlife because they tend to be skittish, frightful of people and non-aggressive, although they will bite if they perceive danger (and if you are close enough, which of course is unreasonably close if their teeth can make it into your skin!). When given appropriate respect regarding space and interference, muskrats are virtually harmless to humans, and fascinating and entertaining little creatures to watch for anyone who stops to take time to appreciate them. A fluffy, adult muskrat ranges in size from 10-14 inches in length and weighs two to three pounds. Muskrats are excellent swimmers and can stay under water for up to 15 minutes at a time. Their webbed hind feet, great for swimming, are much larger than the front five-toed feet used for digging and manipulating food. They are nocturnal, although often seen during daylight hours working on their house, and spend most of their life in water. They are primarily plant eaters feeding on roots, shoots and leaves but will enjoy frogs, small fish, crayfish, mussels or clams if available. Muskrats are rodents and capable of chewing through almost anything, so a metal enclosure at the shelter is the only way to go as our little one physically develops and matures. And because they are timid, his enclosure will be stocked with leaved limbs, many hiding places and water pans to laze about in. In defense of the chewing “in the wild” muskrat, they seldom invade our residential spaces because they are always close to water, and usually marshy, human uninhabitable wetlands at that. Muskrats do not build lodges like the beaver, although they will occasionally move in with beavers. Instead of lodges they construct free standing houses by piling aquatic vegetation into a hill only a few feet high, then excavate a nest cavity in the center with several chambers and tunnels leading into the water which is quite impressive and masterful engineering. The grassy muskrat residence is called a ‘push-up’ or ‘mound.’ Sometimes they build the mounds around trunks of dead bushes or trees. In contrast to a beaver’s lodge, there is often no structure below the water, but muskrats and beavers are the only mammals that build homes on water. Also, unlike the beaver, the muskrat does not store food for the winter. They need to eat fresh plants every day and maintain a home range of less than one mile from their push-up. Muskrats can breed any time of the year and more than once with pregnancy lasting 25-30 days. The litter size averages four to six and kits are hairless, blind at birth and weigh less than one ounce each. Over time the youngsters are weaned from mother’s milk and often stay with their parents for a year, but when overcrowding develops, the parents, usually Mom, dramatically and sometimes, harshly, encourages her eldest children to move out and build a home of their own. Every time a muskrat is admitted to our shelter, we still reminisce the story of a young muskrat found scratching at the back door of a nursing home in Ontario, Canada during a horrific snow and ice storm. One of the workers let her in and fashioned a warm kennel with food and positioned deep, functional water pans for her necessary water moments in efforts to keep her safe during the wretched and dangerous weather. The question of why she came to the door was never truly answered but a few theories were; the weight of the snow collapsed the push-up or a predator, such as a wolf or mink, tried to dig in, but she was smart, lightning fast and managed to escape. Although the plan at the nursing home was to release her back into the wild in the spring, she became very content with her newly-found caretakers and remained with the residents of the home. Now that’s a true story of “Muskrat Love!” We love them too, even if we are way south of Canada! We don’t see muskrats as often in this area, but we are aware of their importance to our ecological system and how they benefit many wetland species by creating open water areas for waterfowl. They are excellent environmental partners for they are true indicators of environmental quality.

Best Always and let’s bless America (and the world) by living

harmoniously with nature, wildlife and each other. . . . . . . . .

Linda Bergman-Althouse

author of “Save Them All

“BIG (but little) BROWN BATS!”

Yes, I am a mammal, and Yes, I can fly! The only mammal that is truly capable of free flight and able to launch under their own flapping power from a still position is a bat. They are not gliders like Southern Flying Squirrels, and like other mammals, they give birth to and nurse live young. Big Brown Bats, who are not very big at all, are one of the most common bats in North Carolina. Although their bodies are about five inches long, not counting the tail, and they have a wingspan up to 13 inches, they weigh only .5 to 1.5 ounces. Big Brown Bats have brown fur above and paler fur below. Their wings are black and devoid of fur. The bat’s wing is an extension of the skin of the abdomen that runs to the tip of each digit, uniting the forelimb with the body. It’s comprised of two tightly stretched layers of skin membranes joined by connective tissue without any flesh between layers. We are able to see through a bat’s wings because of this anatomical construction. This formation of skin membranes is called the patagium. The first digit of a bat’s wing, which is similar to our thumb, is small, clawed and used in climbing or walking on the ground. Their unfurred ears are rounded and dark in color, matching their wing membranes and tail. Their lips are fleshy and their nose is quite wide for the size of their face. Bats are not brought to the Outer Banks Wildlife Shelter in Newport for rehabilitation, but we do get calls asking about them. Some calls, from environmental enthusiasts, question how they can encourage a bat colony to reside in their neighborhood, because they are aware that bats help keep pesky insect populations down. One caller wondered why a bat seemed to be parked on their swimming pool pump during the day when bats are usually not active. That bat turned out to be a youngster just trying his wings and, unfortunately, didn’t make it home before morning. Bats are primarily nocturnal (active only at night), though they also forage in the early evening and early morning hours. All bats found in North Carolina eat insects and because they are nocturnal, they feed on nocturnal insects including mosquitoes and many important agricultural pests. A large colony of Big Brown Bats can eat 18 million corn rootworms each summer placing them in the roles of farmers protecting valuable harvests. A single bat can wipe out 21,000 insects, such as moths, flies, wasps, flying ants and beetles (their favorite meal), annually. All bat species can have a major impact on controlling insect populations, therefore bats are integral to ecosystems worldwide. A nursing female may consume almost her entire body weight in insects in one night. Just imagine how many insects an entire colony of bats would consume. Tropical bats disperse large amounts of seed and pollen, which aids in plant reproduction and forest regrowth. Although bats have relatively good eyesight, most depend on their expertly developed echolocation (or sonar) system to navigate and capture insect prey in the dark. By listening to the echoes reflected to them, they can perceive objects and bugs in their path by size, shape and texture of any tiny insect from its echo. Their echolocation ability is so acute they can avoid obstacles no wider than a piece of thread and capture some itty bitty flying insects, even in complete darkness. Bats produce ultrasonic sounds through their mouth and nose to communicate with each other. You won’t see them, but Big Brown Bats are roosting during the day in hollow trees, beneath loose tree bark, in the crevices of rocks, or in man-made structures such as attics, barns, old buildings, eaves, and window shutters. Bats have adapted well to our urban and suburban environments. Bats can also be found in and around commercial buildings and bridges. The most common place to find bats in homes are the gable vents. Gable vents are screened vents located in roof peaks that aid in proper attic ventilation. Bats generally don’t come in contact with humans unless they are sick, injured or have moved into your house. Despite misconceptions, rabies is not very common in bats, but it’s still best to avoid handling bats and to always use proper caution in their presence as with any wild animal. Big Brown Bats mate during the fall and winter before they go into hibernation, but the female does not become pregnant until the spring as she stores the sperm during hibernation. Female Big Brown Bats form nursery colonies to raise their young. The size of these colonies can vary, but usually fall within the range of a modest 20 to a massive presence of 300. Bachelor BBB’s roost alone or in small groups during this time. In late May or early June, the female gives birth to one or two pups. The babies are born blind, with no fur and completely depend on their mother for nourishment. They grow quickly and will fly within a month to six weeks. The North Carolina Wildlife Resources Commission conducts monitoring studies in a variety of areas across our state to ensure the protection and presence of the Big Brown Bat continues as it is an environmental partner who improves our quality of life. Through a variety of methods, such as mist netting, trapping, banding and radio telemetry, commission biologists collect age, weight and gender information on bats so they can track species distribution and locate hibernation areas which helps to develop effective conservation plans. You can do your part to conserve bats as well by installing bat boxes around your home, planting native foliage that attracts helpful insects to provide food for bats, limiting the use of insecticides and herbicides, avoiding hibernation areas and maternity colonies, joining a conservation organization to remain updated on bat conservation efforts and continuing to educate yourself and others regarding the importance of bats and why they are beneficial. Bat populations have declined over the years mainly due to pesticide use and human disturbances, as well as, persecution. Natural predators include snakes, owls and raccoons, but if a bat can outwit, outplay and outlast predation Big Brown Bats are relatively long-lived mammals and can survive 20 to 30 years in the wild. That is a mighty long, free contract we can all enjoy with our furry, flying natural pest exterminators!

best always,

Linda Bergman-Althouse

author of “Save Them All