Each year in early spring we remind our readers to be conscious of conditions in nature. All work simultaneously and affect wild creatures' behavior. In the rehabilitation network, birds waiting for spring release are becoming restless, beginning to sing, and many are molting due to inside temperatures.
All are waiting impatiently to join their own kind and enjoy the rites of spring. In nature that means find a mate and reproduce.
When most people feel they are still in the "dead of winter," many wild mammals are entering a period marked by a flurry of mating activity.
It is necessary for many animals to mate in late winter to synchronize the birth of their young with spring's milder temperatures, and more plentiful foods.
Wild babies are brought into the world in April and May when they stand a better chance of surviving the rigors of the wild.
People can easily recognize when wild animals are on the move again. All you have to do is look at the dead bodies littering highways to know that raccoons, skunks, and other mammals are out of their winter dens. Also, early spring snow is usually well marked with various tracks telling their unique stories.
Teaching people of all ages to recognize the tracks in their own back yards is one of the most enjoyable educational programs that the Center conducts. Once people get the hang of who is visiting their back yards, you can read enthusiasm for wild creatures on their faces, and hear it in their conversations. Young children in primary grades especially enjoy this program.
Skunks and raccoons have a gestation period of some 63 days. The first young enter the world around mid-April. From mid-May and early June, wildlife rehabilitators begin getting calls to nature orphans.
The eastern coyote is another mammal with a gestation period ranging from 60 to 63 days making its young arrive in early spring. Coyotes actually mate in late January or February making a litter of five to 10 pups arrive in mid-April or early May.
Female red and gray foxes come into heat in late January. Mating usually occurs in February extending into March in the northern and mountainous regions. Gestation is about 51 days.
The bobcat, one of America's most elusive creatures, mates in mid-February. Gestation takes between 50 and 60 days. Kittens are usually born in April and May.
By late February and early March, rabbits, mink, muskrats, woodchucks and chipmunks begin to find mates and reproduce. Approximately one month marks the gestation of these species.
However, the mink is a bit different having a gestation period of some six weeks rather than four. April hosts the arrival of mink kittens.
Winter is a time of silence in nature. You can go for a walk in snow laden woods and hear yourself breathe, walk and perhaps even think a bit. Winter birds move through the woods looking for insects and seeds without songs or calls. They are as mute as the time of year.
Suddenly, about mid-February, winter's long silence is broken. For the first time in months, day breaks with bird songs and calls. When you hear the birds sing again, you know winter is losing its grip.
The urge to sing is beyond birds' control. It is the photoperiod. It is the lengthening of days. It is early spring. The light is changing. Early spring's light is like no other.
Early spring's light activates birds' hormones through the pituitary gland. Birds respond to increasing light by returning to breeding conditions. Songs are sung to stake out territories and attract mates.
Winter's silence is broken by a territories permanent residents firsts. The cardinals, tit-mice, chickadees, and other birds that refuse to leave home territories during winter sing first.
One of the earliest avian singers is the black-capped chickadee. Traveling in roving bands forging for food in the winter, these birds become more solitary as the days grow longer. Often, when one chickadee sings, others soon join in song.
The tufted titmouse is a close relative of the chickadee. Formerly a southern bird, the titmouse has expanded its range north for some two decades now. It is well established even as far north as southern Ontario. However, it is still absent in northern New England.
Another familiar sound in early spring is the mourning dove cooing. The mourning dove positions a few twigs together, calls it a nest, and begins laying the two eggs that produce the familiar pair of babies. In many areas of the country, mourning doves may have as many as five clutches of two babies every year.
Cardinals and mocking-birds are also among the first early spring songsters to announce that winter is over. You can't really call some of the avian sounds songs, but announcements they are.
Woodpeckers are busy communicating as well as many of the song birds. They drum on dead tree trunks to attract a mate and announce territories. This is true from the smallest to the largest pileated ones. All are busy attracting mates or renewing old acquaintances.
Soon new families will be raised in protected territories. Listen carefully as early spring birds announce the arrival of another season.
Northward migrating Canada geese can be heard honking overhead as they make their way home to nest. It is a comforting feeling to look up and see them winging their way north.
Woodcocks can be heard again in the wetlands as their nest and reproduce. For those of us who work with wild creatures, the witnessing of nature's most ancient rituals is refreshing and challenging. Another year is beginning not only for the birds and wild animals, but for those who work with them.
© Copyright North American Wildlife Health Care Center
P.O. Box 155
Black Mountain, North Carolina, USA 28711
A non-profit 501-3-C organization dedicated to wildlife research and education