DON'T MESS WITH THE SWANS

My wife is terrified of swans. Back in 1957, while laying upon an air mattress on a small lake in Switzerland, Toni, then 15 years old, was suddenly beset upon by an angry parent swan with youngsters. She had not heard the warning cries of passersby on the shoreline to get out of the water. As best as she can remember, she quickly clambered off the mattress and flipped it over on its edge to create a defensive wall between her and the aggressive bird while pushing herself to the shore. The water was deep right up the break wall, but she somehow managed to extricate herself from that rather dangerous situation. To this day, Toni has been emotionally scarred by the event, and if we ever were to find ourselves being chased by a territorial swan while paddling in our sea kayak, I am certain that my wife would be frightened out of her wits. Ironically, we now live near Victoria, British Columbia and we have all three species of swan -- trumpeter, mute and tundra -- frequenting our waters and fields at one time or another. We do encounter the odd pair of swans from time to time while kayaking in the Gulf Islands, but we have always managed to avoid any unpleasant interactions. It can easily happen too. A buddy of mine told me that two years ago, he was with his dog in a small motorized dinghy in the same area and a pair of swans, likely mutes, aggressively chased his boat for quite a distance.

Neither party was as unlucky as Anthony Hensley of Des Plaines, Illinois, just outside of Chicago. As a 37-year father of two working for a condo company that had actually provided swans (I am guessing that they were mute swans) to dissuade Canada geese from invading the property, it was Hensley’s job to care for the birds. On April 18th, 2012, while he was out in his kayak on Bay Colony Pond, one of the two swans attacked his boat, causing him to capsize. He was fully dressed and struggled to swim ashore, but the large bird kept blocking his way by lunging at him. Fatigued by the weight of his clothes, Hensley ended up drowning. In April 2014, his wife launched a lawsuit against his employer and the condo complex for not adequately warning her husband about the dangerously aggressive nature of the swans. No word yet on the outcome of the case.

Most likely, since this was April when swans lay their eggs, this particular bird was a male defending a nest with eggs, near to which Hensley unwittingly paddled. Some wondered why the man did not defend himself more vigorously, but consider that he was fully clothed, getting more and more fatigued by the moment, and totally panicked. Prime conditions for drowning to my mind.

Interestingly, I read over the hard-copy accounts on all three swan species from the Birds of North America series jointly published by the Academy of Natural Sciences and the American Ornithologists Union and there was no mention of any attacks of swans on humans other than a reference to incidences whereby mute swans “displayed aggressive behavior toward the house’s occupants, human or pet”.

In the public domain on the internet, there are a number of accounts of swans not only attacking, but also injuring humans, particularly in Europe where mute swans are more abundant in public areas. The victims are usually rowers, kayakers and anglers venturing too close to either nests or adults with young (AKA cygnets). For instance, in April 2010, a swan on the River Cam in England made national news after repeatedly attacking rowers and causing cuts and bruises. Described as “vicious”, the bird was apparently nicknamed Mr. Asbo, after the Anti-Social Behaviour Orders issued by UK courts at the time. During rowing races, the organizers even had to hire a marshall to fend off the bird. In 2012, due to his continued seasonal attacks on rowers, swimmers and kayakers, Mr. Asbo was captured by the river authorities and translocated to another location 60 miles away. The story does not end there. Now he has a grandson, who is even more vicious! As recent as April 2015, Asbaby, which still sported some brownish plumage then, was not only attacking rowers on the Cambridge River, but started going after tourists, eating their sandwiches, drinking from their water bottles, and even trying to steal a woman’s handbag. One can only imagine how many of these incidents were initiated by the silly tourists themselves. Asbaby was fathered by Asboy (the son of Mr. Asbo) who had a reputation for injuring a canoeist, a swimmer, and even attacking a cow! Apparently, Asbaby’s temper is even worse than those of his father and grandfather.

Keep in mind that swans are one of the largest waterfowl in North America and Europe, weighing up to 28 pounds and with a wing span of up to 7.9 feet; they are among the heaviest flying birds in both the UK and North America. While swans, like geese, do use their strong beaks to bite and pull, their most dangerous weapon is potentially their wings. These large and powerful birds are quite capable of flicking their “elbows” forward to cause serious injury to a limb of a combatant, such as a fox or coyote. But to be fair to the swans, incidents of any serious harm are very rare. And in almost all cases, such attacks are caused by folks venturing too close to nests or young or by misguided people feeding the birds, causing them to become tame around humans. Biologists who have handled swans for years say that they have never been injured by them beyond a bruising. And some swan experts claim that a swan breaking a human’s arm or leg with their wings is simply a myth. While I remain convinced that such an injury is possible under certain circumstances, I have to agree with them. However, it is safe to say that because of their large size and their sometimes highly aggressive nature, the behavior of a swan attacking oneself just seems terrifying to most of us. Do not get me wrong either --- I will always give these particular birds a wide berth, especially when they are “busking”. That means that the bird’s neck is curved backward, the wings are half-raised, it is making a lurching forward motion by paddling both feet, it is hissing like the devil, and it is mad as hell! Enough said!

Now that we have put that myth to rest, I would now like to tackle a puzzling behavior presented to me recently by a reader. Elsa Lichman writes the Nature in the City column for her local newspaper, the Waltham News Tribune, in Massachusetts. She has been observing swans at the bank of the Charles River and in a small cove, called Purgatory Cove, for years, and she has noticed a strange behavior. While standing on the ground or in the shallow water, a swan will pull debris from the water with its bill, for example, twigs, wet leaves and other detritus and place it in a pile or even two piles on the bank. Elsa has seen males, females, and cygnets perform this act and she wonders if they are clearing or cleaning the area for better access to whatever food they desire at that location.

Elsa’s suggestion is not a bad one. Swans prefer to forage for aquatic vegetation in shallow water where they can reach bottom with their long necks. In fact, it is that long neck that allows swans to avoid competition with the shorter-necked ducks and geese; they can ‘feel’ for food in deeper water. While swans do much of their feeding by holding their bills horizontally and skimming the surface for tasty items, they also dip their necks in water ranging from 8 to 32 inches deep. But when in water 18 to 42 inches deep, swans often like to upend themselves by submerging almost all of their body except their tail and their feet to search for food. They can do this for about 12 seconds on average. When their feet are available though, swans use them to engage in light to vigorous paddling to dislodge vegetation so that it floats to the surface to be consumed by themselves and/or young (AKA cygnets). Their large skulls which allow for extensive muscles in their bills, the coarse edges on their beaks, the 25 vertebrae in their long necks, a large nail on the tip of their upper mandibles, and a spiny surface on their tongues facilitate them tearing off shoots from vegetative material from the bottom, leaving the roots intact. They usually eat only a small portion of the uprooted plants, leaving the rest on the ground untouched. Even while feeding in agricultural fields, swans frequently pull up and discard much more food than they actually eat. Perhaps the swans that Elsa was observing were discarding uneaten food on the shoreline or as she suggested, the birds are clearing out the area for better access to more desirable foods. I could find no mention of food-storing behavior in swans in the literature.

Another possibility has to do with nest-building behavior. Male swans (AKA cobs) choose several nest sites on the shoreline, which may or may be ultimately selected by the female (AKA pen). In the end, both sexes build the nest together by gathering rotting vegetation like reeds, cattails, twigs, and branches from within four or feet from a given nest site. The male builds the initial platform, but the female molds the nest cup. It all sounds like an intricate process and does not conform to what Elsa was seeing. However, perhaps the swans were placing potential nesting material on the shoreline for later use in nest-building. This would not explain though, why Elsa also saw cygnets performing this behavior and more important, why the behavior was performed well outside the nesting season.

So, this behavior will have to remain a mystery until more studies of swan ecology have been completed.

READERS OBSERVATIONS

Speaking of waterfowl and foraging behavior, how about this interesting observation from Bob Buttery of Albuquerque, New Mexico? One day at the Rio Grande Nature Center located in that city, he and Sondra Williamson, a volunteer at the facility, were sitting on a sofa in the bird observation room with its ceiling-high windows overlooking a pond used by many species of ducks, waders, and songbirds. A favorite attraction are the hummingbirds using the feeder suspended from a long arm out over the pond. Suddenly, a male black-chinned hummingbird struck the window right beside them and fell, stunned, into the pond. Unable to provide any help, Bob and Sondra observed something that they had never seen before --- a hummingbird swimming, using his wings to reach some aquatic vegetation on which to perch and dry off. Then they witnessed another astounding event! Before the bird could reach safety, a mallard in eclipse plumage swimming nearby darted ahead and swallowed the little bird headfirst! Apparently, it took several minutes to complete the job. Bob has birded for more than 70 years and this was the first time he had ever seen either a swimming hummingbird or an omnivorous duck.

COMMENTS

It is not often that one gets to see something that has not yet appeared in the scientific literature, but I believe that Bob and Sondra have managed to do just that and not just once but twice in one sitting! I could find no mention of hummingbirds swimming nor could I find any reference to mallards eating a bird of any kind. With regard to the swimming behavior, I suppose that any bird finding itself plunked into the water will employ its wings to “swim” or row to safety. Success will, of course, depend, on how far they have to swim and the conditions of the water. As for that opportunistic mallard, Dr. Rodger Titman, a retired professor in Montreal and one of the authors of the Birds of North America account on that species, is a very close friend of mine and he informed me that he had never heard of a mallard swallowing another bird whole. The closest thing I could find on the dietary habits of this species in the Birds of North America account to a food item of an “animal” nature for mallards are snails and shrimp. Keep in mind though that a tiny helpless hummingbird can provide a quick, tasty snack filled with sweet nectar and good sources of fat, particularly during the late summer and early fall when hummingbirds fatten themselves up for migration. Due to the double novelty of this observation, I would encourage Bob and Sondra to investigate the possibility of submitting their observation to a scientific journal.