QUESTION: I used to work on the Delaware River about five miles south of the Memorial Bridge on the Delaware side. One morning I witnessed two does swimming from the Jersey side, which was more than two-miles-wide in a brutal current. It took them a good hour to cross. I rarely see deer take to the water like that, but a friend said he once ran into a doe with a boat smack dab in the middle of the Chesapeake Bay!
Besides loss of habitat or pressure, is swimming a normal occurrence for deer, especially such great distances and out of their home range? - Tony S.
ANSWER: It is human nature to try and simplify things to the point where we can comprehend them, and a deer's home range is a classic example.
There have been oodles of studies on whitetail home ranges and movement patterns, results of which are published in scientific journals.
It then falls on the shoulders of outdoor writers to interpret and translate this information into something understandable to the average outdoorsman.
Over time, that interpretation gets further diluted until we end up with something overly simplistic, like an average home range of one square mile.
That's not necessarily inaccurate. But most folks fail to consider that averages are generated from a collection of numbers - often a fairly large collection.
Deer might have an average home range of one square mile, but some regularly occupy far less in good habitat and far more in poor habitat.
And home range can be influenced by many factors. In northern climes, deer might migrate 10 miles or more to traditional wintering areas. Yearling bucks often disperse from their natal home range, and a five or 10-mile dispersal is not unusual.
Adult bucks often travel far outside their core areas during the rut. And deer sometimes move depending on food availability and hunting pressure.
In general, deer tend to avoid crossing larger water bodies and waterways. That doesn't mean they can't or won't.
Deer are actually fairly good swimmers, and will cross water if pushed or are somehow inclined to do so.
I live near the coast of Maine where it's not unheard of for deer to swim between islands, or back and forth between islands and the mainland, sometimes traveling several miles.
What you observed isn't what we might consider a normal occurrence, but it's certainly well within the realm of possibility for deer behavior.
A professor of mine once said, "If what you observe in nature differs from what you learn in class, nature is right." And for every rule there are exceptions.