During Houston’s infancy this area was only a small part of the forest and prairie that covered southeast Texas. Urban expansion has limited this once great forest to many small pockets, influencing the number and diversity of all animals, particularly mammals. Some mammals have benefitted from urbanization. Opossums and raccoons have added garbage to their already generalized diets. Most mammals have suffered. Large mammals like bison, white-tailed deer and red wolves once ranged throughout the area, but were displaced locally by urbanization.

Even if you do not see mammals you can still tell that they are at the Arboretum. As you walk through the Arboretum look for the signs that show you where these animals have been active:

  • Tracks along the trails and edges of ponds
  • Excavations under tree roots, in stream banks, or on top of sandy mounds. Commonly these are dug by armadillos, but they are used by many forest inhabitants.
  • Tunnels crisscrossing along the forest floor where moles have been hunting for earthworms and other invertebrates.
  • Pellets left on logs and other elevated surfaces by rabbits to mark their territories.
  • Leafy nests built high in trees by gray and fox squirrels.
  • Scattered pinecone scales and cores discarded by feeding squirrels.

The diet of raccoons is quite varied. More than one half is plant material-particularly acorns, berries, and other fruits. The remainder of their diet consists of insects, small mammals, crayfish, amphibians, reptiles, and birds. You will see their tracks widespread on our Nature Center trails and along the margins of ponds.
Fox Squirrel
The Fox Squirrel is the largest and most common squirrel in the Arboretum. It has a rusty brown to gray back with orange-tan underneath. These squirrels feed primarily on nuts (acorn and hickory) and seeds (pine and maple), but also eat fruit, leaf-buds and even insects. Both gray and fox squirrels build a basket-sized, leafy nest. These nests are generally occupied during warmer months, but are most visible in fall and winter.
Virginia Opossum
A relative of the kangaroo, the Virginia opossum is the only marsupial native to the United States. Following two week gestation period, the young are born in a helpless and immature state, but with well developed fore-limbs. The young climb unaided to the fur-lined pouch where development will continue for another two months.
Nine-banded Armadillo
The armadillo is one of Texas’ most unique and recognizable mammals. Its shell-like covering is not hard and bony like a turtle, but tough and flexible. It provides good protection from thorns and braches but little insulation. Armadillos will shiver and seek the warmth of their burrows when temperatures drop below 72 degrees Fahrenheit.

The armadillo’s diet consists primarily of insects and other invertebrates which are located almost exclusively by smell. The body form reveals much about its feeding strategy. The compact legs are supplied with four toes on the front feet and five on the hind, each terminating with a large strong claw well adapted to digging.

Southern Flying Squirrel
A secretive member of our wildlife community, the Southern Flying Squirrel is more often heard than seen. This small squirrel scampers up trees, launches itself into the air and uses the flap of skin (patagium) stretched between its front and back legs to glide up to 350 feet! Flying squirrels use their tails as rudders to help them steer while gliding. It feeds on a wide variety of foods including mushrooms, nuts, insects, and even baby birds.
Swamp Rabbit
Swamp rabbits are a familiar sight in wet areas throughout the forest. When necessary, these rabbits will take to water to escape predators or ford flooded sections of forest. Young are commonly born in fur-lined grass nests built in shallow depressions at the base of fallen trees, brush piles, and thickets.
The Coyote is the largest mammal that frequents the Nature Center. It is the size of a German Shepard with a grizzled tawny coat and a bushy tail that sports a black tip. These wild dogs range widely in their search for food which includes rabbits, mice, squirrels, and other small mammals. They also eat birds, frogs, toads, snakes, insects, carrion and many kinds of fruit. Coyotes are very wary of people and will often dart into the brush when seen. Their movements in the Nature Center are most often detected by the scat, and tracks they leave behind.

Some other mammals found at the Arboretum include:

  • Cotton Rat
    Eastern Woodrat
  • Evening Bat
    Eastern Red Bat
  • Big Brown Bat
  • Brazilian Free-tailed Bat
  • Eastern Mole
  • Eastern Gray Squirrel