|photo by Sandy Bacon|
Tuesday, December 29, 2015
Our Backyard Swans
When I was growing up, my family visited the Swan Boats in the Boston Public Garden somewhat regularly – usually on Mother’s Day. For years, I thought of the swan as a rare species – something one could only see at a special place -- never in the wild. But then in the 1980s a pair of swans took up residence in “the pond” behind our house. They -- and their successors -- have pretty much been there ever since. Elegant, with long curving necks and a seemingly serene demeanor, they always manage to capture our attention.
“The pond” behind our house is actually a wide upstream portion of the Green Harbor River. It is relatively secluded -- bordered in large part by the Hoyt-Hall Preserve, a parcel of conservation land managed by the Wildlands Trust of Southeastern Massachusetts. There are a few private homes along the riverbanks as well, and also the Garretson cranberry bogs. It often feels like the swans out back are “ours,” as there are only a few people who can see them!
It turns out that swans are not especially rare in our part of Massachusetts, and while technically they are an exotic species – meaning they are not native to our region – they’re somewhat commonplace. That doesn’t make them any less captivating, though.
Our region’s swans are members of the species Cygnus olor -- the mute swan. They were brought over from Europe and Asia to the United States in the late 1800s for use as living, breathing pond ornaments in parks and on private estates. The prevailing assumption is that some of them found their way into the wild, and gave rise to a slowly-increasing population. Today mute swans can be found up and down the coastline from Maryland to Massachusetts. Here in our state, they are concentrated primarily on Cape Cod and the Islands, with a decent number from Plymouth to Cohasset as well.
Up until the 1970s, mute swans were indeed rare to these parts. But the Massachusetts Audubon’s 1974 Christmas Bird Count identified 200 individuals in the state, and by the mid-eighties, there were 135 mating pairs, with closer to 600 in the winter, due to migration. (They seek refuge in unfrozen ponds and bays.)
The mute swan is striking. Its size alone is impressive. One of the heaviest of the flying birds, a typical adult male weighs from 20-32 pounds and extends to 55-63 inches in length. That’s more than five feet! The mute swan is completely white in color, save for its orange and black bill. Despite what its name suggests, it isn’t actually mute, but it is known to be quieter than other swan species. Still, it grunts and snorts and sometimes makes a hoarse whispering sound, and will hiss at predators such a snapping turtles and coyotes. Its wing flaps are loud, though. We frequently hear “our” swans taking off in flight.
Young swans are called cygnets. They are usually not stark white, but rather gray or off-white. The beak doesn’t turn orange until after the first year. Cygnets make more noise than their parents -- they will chirp and whistle and even squawk if in danger.
You may have heard that swans mate for life. It’s a romantic notion, and true too (mute swans are indeed monogamous), but their lifespan averages just 6-10 years. Mute swans typically inhabit coastal ponds and tidal creeks, and often return to the same nest year after year. They build large nests in shallow water or on islands within ponds and lakes, foraging for materials nearby. One advantage of their long shapely necks is their ability to harvest and feed on submerged aquatic plants.
A female mute swan lays eggs in April or May – 4 to 6 at a time – and then sits on them for 5-6 weeks. The male stays close-by, and when the cygnets hatch, the family stays together for 15 weeks before the young are able to fly. The mortality rate is high. Due to extensive predation, most cygnets do not survive.
As beautiful as they are to behold, mute swans are not friendly. They’re protective and territorial, and will attack even a human if it gets too close. If a mute swan senses another creature encroaching upon its territory, it may rush at it, attempt to bite it, or perhaps assault it with the spurs on its wings. That probably explains why, after all these years, we’ve never seen more than one family of swans on our pond at a time.
While state regulations deem it illegal to hunt them, mute swans aren’t exactly a favored species here in Massachusetts. Non-native, they are considered to be invasive as they drive other, more welcome, species out of their natural habitats. Swans can also be a nuisance to farmers, as they not only consume cereal crops such as wheat, they also trample them. Swans are best left undisturbed, but if you have a serious problem with them on your property, contact Mass Wildlife for assistance (508-759-3406).
by Kezia Bacon
Kezia Bacon's articles appear courtesy of the North and South Rivers Watershed Association, a local non-profit organization devoted to the preservation, restoration, maintenance and conservation of the North and South Rivers and their watershed. For membership information and a copy of their latest newsletter, contact NSRWA at (781) 659-8168 or visit www.nsrwa.org. To browse 19 years of Nature (Human and Otherwise) columns, visit http://keziabaconbernstein.blogspot.com