Moles

Overview:

Moles are mammals, in the order of insectivore. They are not rodents. The presence of ridges or small mounds of soil on the surface of lawns or gardens can indicate that moles are active in the area. Moles establish extensive tunnel systems to find food. They prefer moist soils. Moles mainly eat earthworms and white grubs; they will also eat beetles, spiders, and other insects that venture into their underground tunnels. They seldom feed on plant material. Lawn irrigation systems create a consistently moist, loose soil surface. This results in easy conditions and ample food for moles.

Facts:

• The mole is often confused with the gopher and the vole due to habitat overlap and similar eating habits.
• Moles are not rodents, they are insectivores, and related to shrews and bats.
• Moles do not hibernate.
• Moles contain twice as much blood and twice as much red hemoglobin as other mammals of similar size, allowing the mole to breath easily in its underground environment of low oxygen and high carbon dioxide.
• Mole mounds are shaped like a volcano and can reach heights of up to two feet tall.
• Moles can dig up to 18 feet of surface tunnels per hour.
• Moles youngsters have less than a 50% chance of surviving long enough to reproduce.
• Moles can travel through their existing tunnels at 80 feet/minute.
• Moles eat harmful lawn pests such as white grubs. They also eat beneficial earthworms. Stomach analyses show that nearly two-thirds of the moles studied had eaten white grubs.

Identification:

The adults are from 5 to 8 in. long with dark gray or brown fur. Their feet, nose and tail are pink. The snout and nose of the mole are fleshly and serve as a touch organ. Their eyes are small and only allow it to distinguish between light and dark. Their front feet are equipped with well-developed claws that allow them to dig rapidly

Biology:

Moles have one litter of young in the spring, with 3 to 4 young being the average litter size. The young stay with the female in her tunnels for about a month, and then they leave and start their own tunneling. The young grow quickly and are the same size as the adult in 4 to 8 weeks. The population fluctuates slowly increasing when food and habitat are favorable, decreasing when food is scarce. Young females will not breed until the next year.

Habits:

Feeding
Because moles have high energy requirements, they have large appetites. They can eat 70 to 80 percent of their weight daily. They actively feed day and night at all times of the year. Moles feed on mature insects, snail larvae, spiders, small vertebrates, earthworms, and occasionally small amounts of vegetation. Earthworms and white grubs are preferred foods.

They do considerable damage to bulbs and roots, but their tunneling does most of the damage. They build an extensive tunnel system composed of both deep and surface tunnels. The surface tunnels are usually shallow and appear as if some dirt has been piled on a hose that is lying on the ground.

Tunneling
Moles can tunnel at a rate of 12 to 15 ft. per hour. In favorable areas they can tunnel at a rate of one foot per minute.  Moles prefer moist, sandy loam soils in lawns, gardens, pastures and woodlands. They generally avoid heavy, dry clay soils. They construct extensive underground passageways -- shallow surface tunnels for spring, summer and fall; deep, permanent tunnels for winter use. Nest cavities are located underground, connecting with the deep tunnels. The number of tunnels does not necessarily indicate the number of moles present.  Their tunneling will go on at any time of the day, but the mole will only be seen (if at all), during the night.  Their sensitive eyes make it hard for them to be out during the day.  Moles usually do not share their tunnels with other moles, but shrews, voles or gophers occasionally invade their tunnels. Mole activity in lawns or fields usually shows up as ridges of upheaved soil. The ridges are created where the runways are constructed as the animals move about foraging for food. These ridges can make lawn mowing difficult and the roots of the grass are disturbed, and may turn brown and unsightly. Moles rarely eat flower bulbs, ornamentals or other vegetative material while tunneling, but plants may be physically disturbed as moles tunnel in search of food sources in the soil. Burrowing activity occurs year-round, but peaks during warm, wet months. Some of these tunnels are used as travel lanes and may be abandoned immediately after being dug. Mounds of soil called molehills may be brought to the surface of the ground as moles dig deep, permanent tunnels and nest cavities.

Moles leave cone-shaped mounds on the surface of the ground. These usually are not numerous. Most often these mounds contain coarse soil and earth clods. The mole pushes this soil to the surface, especially when digging deep runs. These deep runs lead to a nest and provide tunnels for use in the winter or during the hot times of the summer. In building these mounds, the mole pushes the soil up through the center, much as a volcano is formed. Moles push dirt through vertical tunnels onto the surface.

People often confuse pocket gopher mounds with mole mounds. Pocket gophers are rodents and have different feeding habits than moles. Therefore, it is important to correctly identify which animal you have in the damage situation. In some areas, both animals exist in the same place.

Treatment:

Because moles feed largely on insects and worms, packing the soil with a roller or reducing soil moisture may make an area less habitable for moles. The use of certain insecticides to control these organisms may reduce their food supply, causing them to leave the area. However, before leaving, the moles may increase their digging in search of food, thereby possibly increasing damage to turf or garden areas.

Trapping 
Trapping is the most successful and practical method of getting rid of moles. There are several mole traps on the market. These traps are well suited to moles because the mole springs them when following its natural instinct to reopen obstructed passageways.

Success or failure in the use of these devices depends largely on the operator’s knowledge of the mole’s habits and of the trap mechanism.

To set a trap properly, select a place in the surface runway where there is evidence of fresh mole activity and where the burrow runs in a straight line. Flatten a portion of the burrow set the harpoon-type trap directly over the runway so that its supporting stakes straddle the runway and its spikes go into the runway

If a trap fails to catch a mole after 2 days, it can mean the mole has changed its habits, the runway was disturbed too much, the trap was improperly set, or the trap was detected by the mole. In any event, move the trap to a new location.

Before initiating a control program for moles, be sure that they are truly out of place. Moles play an important role in the management of soil and of grubs that destroy lawns. Moles work over the soil and subsoil. Only a part of this work is visible at the surface. Tunneling through soil and shifting of soil particles permits better aeration of the soil and subsoil, carrying humus farther down and bringing the subsoil nearer the surface where the elements of plant food may be made available.

If the individual mole is not out of place, consider it an asset. If a particular mole or moles are where you do not want them, remove the moles. If excellent habitat is present and nearby mole populations are high, control will be difficult.