Giving squirrels another look

If squirrels in the area seem particularly active this month, chasing each other up and down trees, it is because the gray squirrel has two breeding seasonsÑone in June and one in January. We are all familiar with the gray squirrel (too familiar, some would say) but Maryland has four other species: red squirrel, flying squirrel, eastern fox squirrel, and the Delmarva fox squirrel.

Gray Squirrel

It's interesting that the gray squirrel has been able to thrive as well as it has in suburbia. Unlike most species associated with mature stands of trees, gray squirrels are not dependent on large tracts of unbroken forest to thrive. The gray squirrel, like a number of woodpecker species, has been able to cope with habitat fragmentation, and in fact, has found a niche where many of their forest-dependent predators can't find them.

Gray squirrels are arboreal squirrels, meaning they spend most of their time in trees. Among their adaptations are a specially adapted back foot, which can turn 180 degrees, allowing them to easily go down a tree head first; and a bushy tail, which provide balances when leaping from one branch to another.

Gray squirrels have two types of domiciles. Their preferred domicile, especially for raising young and wintering, is the tree cavity. Squirrels also nest in dreys, or nests made of leaves and twigs, which can be seen built in trees throughout our area. One squirrel may have three dreys, all used at different times.

The lifespan for a gray squirrel is generally seven to eight years in the wild (or your backyard). They molt twice a year, in March and September. Gray squirrels generally have three to four young that are dependent on their mom for a few months, but will themselves be breeding within a year.

Gray squirrels are most active for two hours after sunrise and two hours before sunset. Much of their active time is spent foraging, usually in a home range of about 5 acres. These ranges often overlap, since gray squirrels are not territorial.

The bulk of the gray squirrel's diet is nuts and seeds from a number of different tree species, though squirrels will also eat flowers, bulbs, and even frogs. Most of the water they need comes from dew and the plants they eat.

Grey squirrels can become pests by entering attics or garages, but they do not pose a human health riskÑthey do not generally carry diseases that are transmitted easily to humans, and they very rarely get rabies. Problem squirrels can easily be trapped live and relocated.

Red Squirrels

Red Squirrels, also known as pine squirrels, are found in Maryland mostly in the western counties. The red squirrel is arboreal like the gray squirrel but is about half its size, with a body length of 7 to 9 inches and a weight of 7 to 12 ounces. Though small, the red squirrel is very active and very vocal.

Also distinguishing red squirrels are its white eye ring and a tail not quite as bushy as other squirrels. In summer, red squirrels may have a black line separating the red/brown back from the white belly.

Red squirrels generally bear three to seven young in the early spring, though occasionally there will be a second litter at the end of the summer.

Much of the red squirrel's diet is made up of pine seeds and cones. Because of this, the red squirrel and other squirrels play an important role in the distribution of seed and trees in our state. Red squirrels also like to drink sap, often nibbling through tree bark until sap starts flowing.

Red squirrels are active year-round (with the exception of those in the northern most parts of Canada, which hibernate). Like the gray squirrel, the red squirrel is diurnalÑactive in the early morning and late afternoon. But the red squirrel does not tolerate squirrels of any species in its territoryÑit is highly territorial.

As with most small mammals, its predators are hawks, owls, coyotes and foxes.

Flying Squirrels

Good numbers of flying squirrels are in our area but, being nocturnal, this species of squirrel is rarely seen. Flying squirrels have gray backs and white bellies and a distinctive black ring around the eye. Reaching a length of only 9 or 10 inches and a weight of 2 to 4 ounces, the flying squirrel is quite small.

This species gets its name from its ability to glide long distances, usually 20 to 30 feet, though flights of 240 feet have been recorded. The squirrel is able to "fly" using the patagium, or membrane of skin, that connects the ankles of the front and back legs.

The flying squirrel's reproduction, diet, and nesting are similar to the red and gray squirrels, though flying squirrels are less likely to build leaf dreys.

Both the northern flying squirrel and southern flying squirrel (different subspecies) can be spotted in Maryland. If you would like get a glimpse of a flying squirrel, check out the Brookfield Nature Center in Wheaton, where they take people of all ages on squirrel-watching tours in the early evening. Check out www.mc-mncppc.org/parks/activities/nutshell and click on Brookside Nature Center for more details.

Fox Squirrels

Maryland has two species of fox squirrels. The eastern fox squirrel, a large tree squirrel, can be found along the Potomac River. The Delmarva Fox Squirrel, also a large tree squirrel, is only found on the Eastern Shore and is listed as an endangered species. While both species of squirrels are considered arboreal, they spend much more time on the ground than the gray, red, or flying squirrels.

The eastern fox squirrel is the largest of the North American squirrels and can reach a length of 29 inches and weigh up to 3 pounds. Eastern fox squirrels have a life expectancy of 10 to 12 years.

The Delmarva fox squirrel is quite similar in appearance to the eastern fox squirrel, but it is not nearly as widespread. Its numbers have been reduced greatly by the loss and fragmentation of its habitat, (caused by a number of factors, including timber harvesting, conversion of forestland, and development), and by being preyed upon by domestic catsÑa problem for so much of our small local wildlife.

Good places in Maryland to learn more about the endangered Delmarva fox squirrel include Eastern Neck National Wildlife Refuge in Kent County, and the Blackwater National Wildlife Refuge in Dorchester County.

Takoma Park resident Ned Daly is the Vice President of Operations for the Forest Stewardship Council, a nonprofit which certifies sustainably produced wood. He is the former director of Forest Policy for the Consumer's Choice Council.