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Mammals

What are deer doing in my yard?

Idaho's mule deer and white-tailed deer are "edge" species, preferring to browse in open areas near forests or dense shrubs. Our urban landscapes, with their innumerable edges, are consequently very attractive to deer. On average, deer eat about 7 pounds of food—approximately 3 percent of their body weight—each day. They're most active in the early morning and evening. Deer like to nibble, tasting first one plant, then another and will return to your yard repeatedly if they've learned they'll find good things to eat there. While they like some plants—and some stages of plant life—better than others, they're far from fussy. Deer also drink 2 to 4 quarts of water a day, sometimes from birdbaths or water features. Females typically, they have one or two fawns each spring, although triplets are not unusual for white-tails.

Benefits and conflicts

Who doesn't enjoy watching these graceful animals, especially with their adorable fawns at their sides? However, deer can cause extensive damage to urban landscapes orchards and vegetable gardens by feeding and trampling on plants and by rubbing antlers against young trees and shrubs. Young garden and landscape plants can be severely damaged or killed by these visitors' spring and summer browsing; indeed, deer have a special yen for tender new shoots and buds. Deer will include fruit in their diet during the summer, acorns during the fall and lichen, dead leaves, twigs, bark and evergreen boughs in the winter.

Strategies for coexistence and control

  • Habitat modification: Although deer become decreasingly selective as they become increasingly hungry, there are some plants they are less likely to eat. Among the plants that deer avoid are those with a strong scent and those with thick, leathery or fuzzy leaves or bristly or spiny textures. Many deer-resistant plants are poisonous throughout the year or at some stages of growth. See Deer-Resistant Plants from Colorado State University for more information or deer-resistant plants from Oregon State University.
  • Fencing: Typically, it takes an 8-foot-tall fence — plastic mesh, wood, chain link or wire — to keep deer from jumping into your yard. However, a 5-foot height solid fence may work because deer are reluctant to jump into an area they can't see. Keep them from crawling under the fence by securing it close to the ground. Electric fencing—one to five wires temptingly baited with a 1:1 mixture of foil-wrapped peanut butter and peanut or vegetable oil—can effectively exclude deer from small areas. Successfully lured into being shocked, they learn to stay out. Protect individual trees or shrubs by encircling the plants with staked wire or plastic mesh. Some commercially available trunk wraps are designed to protect bark from antler-rubbing.
  • Frightening devices and repellents: An active dog running loose in a fenced yard can effectively deter deer. Odor- or taste-based repellents can help if they're applied repeatedly, especially after rain or irrigation and if the same repellents aren't used for too long. Once deer accommodate to a particular repellent, it loses its ability to deter them. Flashing lights, for example, work briefly but deer soon learn to ignore them. If you're spraying a repellent on a food product, be sure to check the product label to verify that is an approved use.
  • Trapping: Constraints of labor and expense usually make live-trapping and removing deer unfeasible.

What is a marmot doing in my yard?

In Idaho, we use the name rockchuck for the yellow-bellied marmot (Marmota flaviventris). In some places they are also called "whistle pigs." Marmots are rodents and are the largest member of the squirrel family. They look like an overgrown ground squirrel with a yellow-tan belly. Males can weigh as much as 11 pounds. Marmots live among rocks where they can find and build burrows. Luckily, they do not indiscriminately dig burrows in open ground like their eastern "woodchuck" cousins. They are common in Idaho's warm valleys and are often seen in the foothills, even near cities and also around the edges of lava formations. It is a common sight in southern Idaho to see yellow-bellied marmots in springtime sunning themselves on rocks along roadsides. In the summertime, marmots mostly emerge from their dens and feed at night. For that reason, it is sometimes hard to identify the culprit when damage is discovered in the garden. Marmots tend to live in social colonies, are prolific breeders and can become serious garden pests if present in large numbers. Marmots will eat any tender, green plants but especially love succulent vegetables. They are voracious and a few marmots can strip a vegetable garden in a few nights. Marmot damage is unique in that they eat plants to the ground, giving them a "mowed" look. Other pests tend to be selective in what they eat.

Benefits and conflicts

Marmots provide little direct benefit to the homeowner. They can be interesting to observe during the times of the year they are outside their burrows. Conflict with marmots come directly as a result of their tendency to raid the garden and eat anything that looks like a plant, including the lawn.

Strategies for coexistence and control

In agricultural areas, when marmot damage becomes severe, action is taken to eliminate the problem through shooting, gassing or poisoning. For the homeowner, these options may not be appropriate for a number of reasons. Also, many gardeners are willing to share their produce, as long as the marmots do not take the lion's share. Following are ideas for dealing with marmots if they become a problem.

  • Remove them through trapping: Live traps baited with succulent leaves or sprigs of clover can be used to capture marmots, which then can be moved to a more suitable habitat. To keep the pests from returning, relocate them to a place at least five miles away.
  • Plant a "marmot garden": If the marmots are not too numerous, you can keep them from damaging precious plants by planting an attractive feeding spot close to the den. Given their preference, marmots will eat succulent clover over most other types of plants, so a plot of red or white pasture clover would be a good choice for your "marmot garden."
  • Build a fence: Placing a marmot fence around choice vegetation can be a good alternative, but the job must be done right. Marmots excel at both digging and climbing. The fence must made of mesh wire and be at least four feet tall and preferably bowed outward at the top with the bottom buried 12 to 18 inches into the ground. Or form an L-shaped fence with the lower edge leading outward and buried about 2 inches making it harder for the marmot to dig underneath. In reality, fences are of questionable value in keeping marmots at bay. One exception to this is the use of electrified fencing with multiple wires spaced from just above ground level to about two feet up.

For more information

What is a rabbit doing in my yard?

Because Idaho's mountain cottontails and white- and black-tailed jackrabbits can breed repeatedly from late winter through summer and can eat everything from tender vegetable shoots to tree bark, what they're doing in your yard is probably eating and reproducing. Cottontails can produce a new litter (typically, three to five young) as swiftly as monthly reproducing generally February through August. Jackrabbits take a little longer, 43 days gestation period, but may have up to 8 young per litter. Woody and dense vegetation appeals to cottontails, while jackrabbits favor open rangelands and cultivated fields. Although cottontails often seek shelter-hunkering down under brush piles or dense shrubs, hiding in sheds or hightailing it down the proverbial rabbit hole-jackrabbits typically protect themselves by fleeing (at speeds up to 40 miles per hour).

Benefits and conflicts

Rabbits can be fun to watch, if you're not watching them eat something you'd rather they left alone. During the growing season, they're particularly partial to tulips, carrots, peas, beans, lettuce, beets and grass, although there's not much in the garden or landscape they won't eat if they're sufficiently hungry. In fall and winter, they turn to young trees and woody shrubs, cleanly clipping off small stems, slicing off buds or gnawing on the bark of young trees or shrubs. They can completely girdle and kill vulnerable woody plants.

Strategies for coexistence and control

  • Habitat modification: Remove piles of brush and stone and patches of tall weeds, particularly around vulnerable, newly planted trees or shrubs. Ironically, this sort of garden cleanliness discourages cottontails but pleases jackrabbits.
  • Fencing: Fortunately, rabbits are relatively simple to exclude from vegetable, herb or flower patches with inexpensive fences or domes made of 1-inch or smaller-mesh chicken-wire. In the summer, a 2-foot-tall fence will deter cottontails and a 3-foot-tall fence will ward off jackrabbits. In the winter, you'll want to build the fence higher to reflect your area's anticipated snow depth. Either stake the bottom end of the fence tightly to the ground or splay it outward, burying the bent edge about 4 inches underground to thwart digging. Commercial cylinders or home-made cylinders of 1/4-inch hardwire cloth will protect young trees, as long as the cylinders are tall enough to keep rabbits' incisors from reaching above them and far enough from the trunk to keep rabbits from chewing through them.
  • Frightening devices and repellents: A fleet-footed dog is best; many other repellents have been tried, with far more variable results. Read the label carefully; most repellents aren't intended for use on human food and many must be reapplied after rainfall or irrigation.
  • Trapping: If you know of a gardener who wants the company, cottontails are easy to lure into traps and relocate. Be aware that the ecological niche the dearly departed rabbits will leave in your yard will most likely be filled by neighboring rabbits.

For more information

What is a raccoon doing in my yard?

The omnivorous, nocturnal and nimble raccoon is either prowling for its preferred or staple foods or on the hunt for a den site. In addition to pet food and garbage, raccoons will eat plants (fruits, nuts and vegetables) and animals (grubs, crickets, grasshoppers, frogs, worms, fish, turtles, squirrels, rabbits, rats, mice, bird eggs and nestlings, among others). Raccoons particularly fond of sweet corn and watermelons. In nature, raccoons will den in tree cavities, brush piles or ground burrows. In our yards, these resourceful and often destructive critters will seek shelter in or under any structure they can enter. That includes attics, chimneys, crawl spaces and wood stacks as well as the areas beneath porches, decks, and sheds. Raccoons typically bear litters of roughly three to six young in April or May. These young will stay with their mothers for about a year. In urban and suburban areas, densities of well-adapted raccoons can reach 100 per square mile.

Benefits and conflicts

Raccoons will provide a little help with insect and rodent control, but they can quickly become pests themselves. Besides knocking over garbage cans, raiding vegetable gardens, stealing tree fruit and rolling up freshly laid sod in search of grubs, they can establish dens in chimneys and rip off shingles or fascia boards to enter attics. They may also carry fleas, ticks, roundworms, rabies and canine and feline parvovirus, among other potential health threats to humans and pets.

Strategies for coexistence and control

  • Habitat modification: If possible, remove woodpiles and trim overgrown shrubbery to reduce cover. Also, be sure to secure your garbage cans and lids and to bring pet food and water in overnight.
  • Exclusion: Before attempting exclusion procedures, be sure there are no young raccoons in the area from which you are attempting to keep the animals out of. Raccoons can readily scale fences and even open simple gates. A good way to keep them from clambering over or digging under your fence is to install a single electrified wire 8 inches from the fence and 8 inches above the ground. If you don't have a fence, two parallel wires-mounted about 6 and 12 inches above the ground on insulated stakes-should also work. A commercial sheet-metal chimney cap or heavy metal screen (installed only if you're certain no young will be trapped inside) offers good protection against raccoons in your attic. Trimming tree branches back 3-5 feet from the roof also helps as long as you don't have other landscape structures they can clamber up. To exclude raccoons from open spaces beneath structures, such as a patio, install 1/4 or 1/3-inch galvanized hardware mesh, burying the bottom edge at least 6 inches deep extending the buried portion outward about 12 inches.

  • Frightening devices and repellents: No chemical repellents have been proven effective against raccoons and no frightening devices will work for very long.
  • Trapping: Raccoons are relatively easily trapped but there may be restrictions about relocating. A trapped raccoon can also be very vicious, so it is advisable to contact a professional wildlife control operator for assistance.

For more information

What is a skunk doing in my yard?

Slow-moving, mild-mannered and severely near-sighted, skunks are nocturnal and nomadic. When they visit your yard, they're either looking for food or shelter or simply passing through. Mice, grasshoppers, beetles, crickets and other insects are all important components of the skunk diet. Skunks will also eat eggs, berries, carrion, snakes, frogs, small birds, rats, rabbits and other small mammals and, of course, garbage and pet food. To a skunk, the dark, quiet and often protected areas under decks, porches and sheds all look like good places to bunk for the near term. Abandoned woodchuck or fox burrows, rocky crevasses, culverts, hollow logs and lumber piles make suitable dens as well. Skunks typically bear one litter a year of two to 10 young. The young are born in May or June and are on their own by fall. The normal home range of a skunk is less than 2 square miles, although breeding males may travel up to 5 miles each night.

Benefits and conflicts

Skunks destroy large numbers of garden pests such as grasshopper and beetles. But they can burrow under porches, decks and foundations and slip inside buildings through openings as small as 3-4 inches. Loose in the vegetable garden, they'll waddle over to the sweet corn and eat the lowermost ears. Searching for grubs near the surface of wet lawns, they'll dig 3- to 4-inch-wide cone-shaped holes or upturn small patches of turf. Most annoying of all, when threatened they'll spray to distances of 15 feet or beyond. To their credit, they give fair warning by arching their backs, raising their tails, stamping their feet and shuffling backwards. Uncommonly, skunks also carry rabies.

Strategies for coexistence and control

Habitat modification: You can minimize skunk-related problems by:

  • Keeping cellar, basement and crawl space doors closed
  • Sealing and covering all openings, including window wells
  • Removing debris, brush piles and lumber stacks
  • Keeping pet food inside
  • Covering garbage cans
  • Reducing grub and rodent populations
  • Preventing accumulation of ripe fruit on or below fruit trees
  • Taking precautions before letting dogs out at night

Fencing: Fortunately, skunks aren't skilled at climbing and a fence will normally deter them. They are, however, exceedingly skilled at digging so you'll need a 2-inch wire mesh fence that's not only 3 feet high but that extends 6-12 inches below ground and another 6-12 inches below ground bent outward at a right angle.

Frightening devices and repellents: No repellents or toxicants are registered for skunks, although ammonia-soaked rags, loud radios and bright lights in denning sites may encourage them to seek shelter elsewhere.

Trapping: Call a professional wildlife control operator if you feel a skunk must be removed. Be aware that another skunk is likely to take its place, filling the vacancy that removing the first skunk has left in the environment.

Fore more information

What is a vole doing in my yard?

These small, short-tailed, brown or gray rodents are active year-round, but you're likely to see them only infrequently. They spend most of their time in burrows below ground. Especially during the peaks of their three- to five-year population cycles, voles are drawn to gardens and landscapes with deep mulch and litter and with dense, tall grasses and weeds. They tend to spend their entire, though brief, lives in an area smaller than a quarter acre. They can have one to five litters a year with about three to six young per litter. Unlike pocket gophers, whose burrows are distinguishable by significant above-ground damage, voles leave few visible signs. They reveal their presence by the narrow, aboveground, grassy runways they use between their small burrow openings. Look closely and you're likely to see grass clippings and small green droppings in the runways.

Benefits and conflicts

Voles can eat snails and insects, but that may not be enough to endear them to gardeners. In addition to temporarily damaging the turf in their runways by clipping it very close to the roots, voles feed on many different kinds of grasses, herbaceous plants, bulbs and tubers. In the vegetable patch, they favor artichokes, beets, Brussels sprouts, cabbage, carrots, cauliflower, celery, lettuce, turnips, sweet potatoes, spinach and tomatoes. In fall or late winter, they turn to the bark and roots of trees and shrubs, which they can damage significantly.

Strategies for coexistence and control

Habitat modification: Keep grasses mowed and remove weedy patches at your garden's edge. Clear a 3- to 4-foot circle around the base of young trees or vines; voles don't like to feed where they can be seen. Minimize spillage from bird feeders. Fencing: Fortunately, voles don't climb well. They can be thwarted by a fence made of 1/4-inch or smaller mesh that's about 12-18 inches aboveground and 6-10 inches below ground. Similarly, cylinders made of 1/4-inch or smaller hardware cloth, sheet metal or heavy plastic, pushed into the ground as deeply as possible without damaging plant roots, will protect young trees, vines and ornamentals. Check these cylinders frequently to make sure the voles haven't dug under them. Frightening devices and repellents: Frightening devices are ineffective against voles and repellents offer only short-term effectiveness. Available poisons can be toxic to humans and pets as well as to nontarget wildlife. Trapping: You can trap small populations of voles with mouse traps baited with a peanut butter-oatmeal mix. Set the traps at right angles to the runways, with the trigger ends in the runways. To reduce access by nontarget birds and other animals, cover the traps with a box through which you've cut a 1-inch hole or enclose the traps in PVC pipe. Check the traps daily. Because voles can carry infectious disease organisms or parasites, be sure to handle their remains with rubber gloves or similar protection.

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