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was necessairly reared on P.E.I. The present record is the first . proof of nesting by Hooded Mergansers on the Island.

Hooded Mergansers are the smallest merganser and compare in size to a Ringneck Duck. They nest in tree cavities around fresh water ponds.

Paul Strain 123 Nassau Street 1 CharlottetOWn, P.E.I.

Francis Bain Bird—a—thon and Census, 1978

The first annual Francis Bain Bird-a—thon was held May 28, 1978. The event was a great success in that it provided approximately $650 to the Natural History Society coffers. Those of us participating has a great birding day observing a total of 116 species including a number of migrants. Results of the bird-a-thon are published in the summer issue of "The Environeer".“'Participants were Judy Allen, Lenore Andrew, Roger Andrew, Winnie Cairns, Rosemary Curley, Connie Gaudet, Winston Johnston, Simon Lunn, Margaret Mallett, Kathy Martin, Danny McAskill, Mindy Rowse, Dave Smith, Paul Strain and Mary Willms. We thank our sponsors for their~support.

I Preparations for the 1979 Francis Bain Bird-a—thon will begin early in the new year.

Dave Smith

Newton, P.E.I.

Whale Wash—ups Still Poorly Understood

Despite mammoth size, importance in marine ecosystems, and historic status as human prey, the great whales remain poorly known to science. The recent spate of whales washing up on Island shores has left biologists scratching their heads.‘

Toothed whales normally find their way through dark or murky waters by listening to echoes of the sounds they produce. This echoloca- tion system is extraordinarily accurate, but for reasons known only to themselves, whole "pods" of toothed whales sometimes swim up onto beaches where they strand themselves and die. One species which regularly commits suicide in this way is the pilot whale or bluefish, which is occasionally seen in Island waters.

All of the whales that came ashore on the Island recently were fin whales, a medium—sized (adult length about 20 m) species in the baleen whale group. It is still unclear if most, or any, of this group navigate by means of an echolocation system, although they too are some- times the victims of mass strandings. Whales, of course, may wash up after having died from natural causes, but the question that remains un- answered about the five P.E.I. arrivals (all dead before washing up) is why so many in such a short period of time? These whales have but one natural enemy: The killer whale, which consumes only the tongues of its large victims. Killers are occasionally seen in the Gulf, and their presence was confirmed several years ago by the wash-up of a number of tongue—less carcasses on the north shore of the Gulf. But since the whales washing up on our beaches have their tongues intact, the answer must lie elsewhere.

One possible explanation is that these whales are victims of last winter's ice in the northern Gulf, since winter ice conditions are be- lieved to be the major enemy of whales in this area. A whale inadvertently caught beneath a large ice mass could suffocate before reaching open water, while an individual trapped in an ice flow could sustain injuries from the moving blocks of ice and later die from infected wounds. The badly decomposed whales now appearing in Island waters may have died as long ago as last winter. Early autumn changes in prevailing wind patterns and current flow in the Gulf could be the reason the carcasses are only now showing up.