A couple of years ago, a good friend
asked why I had never done an article on loons; I had no plausible
explanation. Reflecting for a moment, I had promised both my
friend and myself to do some research and write the article. What
I cannot understand is why it has taken me all this time to finish the
project. After all, the loon is such a distinctive and elusive
bird. So prominent in the northern lakes... and the call of the loon
has whispered me to sleep on numerous occasions. It is indeed high time
to pay homage.
Not directly related to any other living
order of bird, the loon's ancestry dates back some 65 million years.
About the size of a large duck or perhaps a small goose, all living
species of loons are members of an order and family all their own:
Gaviiformes Gaviidae. The common loon with which most who vacation
in the north country are familiar are (genus and species) Gavia immer,
or Great Northern Diver - one of five main recognized species.
Gavia, by the way, is Latin for Sea Smew (a small duck, although
loons are not ducks) and immer is Latin for
immersus or submerged - which makes sense of course since loons spend a
lot of time under water looking for food. The average common loon
is about 32 inches long, has a wingspan of some four and-a-half-feet and
weighs close to nine pounds - making it a rather formidable adversary,
especially if the loon is considering you as fresh fish dinner! Summer
plumage is largely black-and-white; black head and bill, checkered black
and white back and a white belly. Easy to spot are the fire-orange
eyes and the classic black and white ring around the neck, contributing
to the appearance of being dressed in a sort of tuxedo. All
species have a spear-shaped bill.
There is a strong indication that loons
mate for life, although evidence to the contrary exists -- mostly due to
loon intruders that will chase one of a mating pair from its breeding
ground. Nests are built close to the water and the same sites are
often used from year to year. The best sites are completely
surrounded by water, such as on an island, muskrat house, half-submerged
log, or sedge mat (a clump of grass-like water plants). Generally
the birds can then slip directly from the nest to water. The
only time a loon spends on land is during mating and as a just-hatched
chick. Even sleep takes place on the water -- over deeper areas
and far from possible predators. Loon courtship begins
just as ice-out is taking place, and can last most of the summer.
There is much bill-dipping, preening, wing flapping and chasing,
followed by the pair heading to the place on shore where mating and
nesting will take place. Usually, two large brown-spotted
olive-colored eggs are laid; roughly a month later, the young chicks
hatch. Already equipped to swim and dive, they hang close to mom
and dad for warmth and for food for the first several weeks.
Once hatched, the chicks are prodigious
eaters, and the parents spend much of the first three weeks or so
catching fish for them. The first couple of weeks are spent in a
"nursery" area or riding on the backs of a parent until they are too
heavy, at which point they hone their their swimming and diving skills.
At eleven weeks or so, the chicks are mature enough to be on their own,
able to swim, dive and catch their own food. The rest of their
life is spent in, on and under the water. The common loon, like
all diving birds, specializes in catching and eating fish; they can dive
to great depths (100 feet or more) and remain submerged for long periods
(up to a full minute) in pursuit of a freshwater diet that consists of
pike, perch, sunfish, trout, and bass; they also eat crayfish, frogs and
leeches. Their legs, although not positioned well for walking --
they are set too far to the rear -- are excellent appendages for
swimming and diving; the birds' wings also aide in swimming. The
loon will sit gracefully erect: head held high, occasionally lifting a
webbed foot to waggle it or stretching and flapping a wing. It
will suddenly dip its head into the water, peering left and right to
locate its prey. Then, in an instant, the bird will silently
slither beneath the surface on another fishing trip, submerged for what
seems an inordinate amount of time... and then reappear some fifty to
sixty yards away with its meal already swallowed. Every now and
again, a loon will accidentally emerge so close to my boat that it seems
we are both wondering who is invading whose space.
Perhaps the most endearing quality of
this often-elusive and skittish bird is the haunting sound of its
plaintive wails, crazy-laugh
tremolos, defensive
yodels and single note
hoots. Many a family member has sat out on the porch of
a cabin around a northern lake and listened to these relaxing sounds --
often at dusk as the lake calms, or perhaps awakening in the middle of
the night to the mournful cry. The Loon call is not only easy to
recognize, it is familiar to many people because of its
prevalence in many movies and relaxation tapes. However, I would
prefer to watch and listen in person; I recall many an evening where the
soulful wails have eased me into a deep sleep, and I would likely
consider my vacation as missing something very important if ever those
sounds went missing.
Having said that, there is an unfortunate
bit of bad news that must be pointed out... The very nature of the
diet of the Great Northern Diver puts the bird at risk, due to the
effects of acid rain and pollution, as well as mercury contamination
from industrial sources and lead poisoning from fishing sinkers.
These toxins become imbedded in the tissue of the fish sought by the
loon for its meals and, once eaten, the toxins also enter the bird.
The result is a loss of breading success and generally decreasing
populations. Sadly, these birds have all but disappeared from some
lakes in North America because of mans' carelessness when it comes to
pollution. The good news is extensive distribution of the common
loon: breeding in most of Canada and northern lakes, and wintering on
both coasts, along the Pacific and Atlantic coasts of North America,
from Alaska and the island of Newfoundland in the north to Mexico in the
south.
If we want to continue to enjoy this
beautiful and worthy addition to our vacation areas, there are several
things that we need to keep in mind to protect the loons on lakes we
visit. Keep your boat well away from swimming birds, especially if
they are with chicks that are too young to dive or fly. Shoreline
areas that look to favor loon nesting should be left undisturbed;
boaters passing these areas should travel at speeds that do not cause
wash -- in some cases, greater speeds actually cause a smaller wake.
And anglers have the added responsibility of using non-lead sinkers and
of ensuring that no hooks or lines are left unattended or abandoned.
A little common sense can go a long way toward protecting our valuable
natural resources!