OutLook for the Bay: Last Words
Perhaps it started with seven swans-a-swimming or escapees from the local zoos or parks, but their numbers quickly grew to more than 4,000 gobblers of the subaquatic vegetation in the Chesapeake Bay. The mute swan, as beautiful a sight as there is, was introduced to America from Asia and European countries. They have now proven to be a nuisance with their unchecked growth. Having escaped captivity, the birds are no longer considered a vision of tranquility in a pastoral setting. With a diet almost exclusively of the Bay’s bottom grasses, and a habit of tearing out those grasses — roots, tubers and all — these swans effectively end any further chance for the individual plants to regrow. With their voracious habit of consuming four to eight pounds a day of bottom grasses, these nonmigratory birds are now considered persona non gratae. Not only do they rip up the subaquatic vegetation, but they can become dangerously aggressive when bothered during their nesting period. Not to be confused with the whistling swan, more commonly known as the tundra swan, this 25-pound bird makes the Chesapeake its year-round home, where it has become a distinct nuisance. These swans are also responsible for scaring off various other species of birds, such as terns, by trampling nests and decimating the food sources for the smaller birds. Due to the dramatic decline of subaquatic vegetation, both swans and geese can now be seen in the fallow fields in the winter months foraging for scraps that the farmer has left behind.
The tundra swan, welcomed for centuries to the Bay area, is migratory and heads out to the treeless plains of northwest Canada and Alaska in early spring as the warm days of summer begin to spread their heat through our area. Laying up to five or six eggs in a clutch, the paired-for-life parents keep their young ones close until a more mature plumage emerges and they’re ready for their up to 4,000-mile flight to the Chesapeake and coastal North Carolina regions. Departing from inside the Arctic Circle in the early fall, they can be observed arriving in the Bay area from late October to mid-November. The Bay waters remain cool enough and most often ice-free, creating a hospitable home for this voracious connoisseur. With eating habits more genteel than the mute swan, the tundra swan tends toward young grasses, mollusks such as clams and mussels and newly hatched crabs. Mute swans, distinguished from their cousins by the orange band found just below the eyes, and the S-shaped neck, are far more destructive than their tundra swan cousins. Rarely targeted by hunters in the 20th century, the tundra is one of two species native to America. The pilgrim’s thanksgiving table probably displayed at least a few of the native swans, as it was considered a fairly good meal by the early settlers.
And as heart-rending as the myth goes that a mute swan sings out an achingly beautiful song only as it dies, there is no basis for the tale other than what’s found in overly romantic poetry. Further, the mute swan is in truth not so mute. They communicate among themselves with hisses and barks and even a purring sound.
As it has in the past, the Maryland Department of Natural Resources is currently taking steps to thin the population through various humane control methods. One such method consists of addling the eggs. The humane methods that have been in place have reduced the current population to approximately 500 year-round residents, thus reducing the numbers to a more manageable size.
Mute swans that were allowed to escape into the wild have taught us a valuable lesson : We need to be more vigilant in our casual attitude towards feral or exotic species that are in the Bay area and that threaten to interrupt the ecological balance of the Bay. With the rapid multiplication of the introduced mute swan, many species of birds and vegetation are now threatened by their destructive nature.