NATURE NOTES FROM ACADIA

A TRIP TO BLACK ISLAND

After an abnormally wet summer which came to a close following a long final spell of rain, the first day of autumn promised a happy change. Out of a clear sky the sun beamed on the coloring woodlands, and its smile was reflected many thousand fold from the blue choppy little waves of the ocean waters which encircle Mount Desert Island. It was on this day that Mr. and Mrs. Lunt of Indian Point and my wife and I drove to a cove on the northwestern shore of the island from where Mr. Lunt rowed us to Black Island, a small body of land lying in Western Bay on a line between Indian Point of Mount Desert and North Point of Bartlett Island. With the water choppy and the tide against us our progress was not very rapid, and we therefore had some little time to look about us.

Above the horizon to the northwest loomed Blue Hill, a bold picturesque monadnock, purple in the distance, with a few light puffs of white clouds hovering over it. Looking back at the shore from which we started we could see its evergreen border - a fringe of dark green spruces, varying in width, which fronts the Mount Desert Island coast almost throughout its entire stretch. A number of white-winged scoters, common sea ducks on these waters, could be seen flying low as we neared the seal rocks.

Most people who have lived long on Mount Desert Island seem to agree that seals are most numerous on the little islands off Indian Point, and it was not long before a number of these inquisitive aquatic mammals put in their appearance. Their rounded somewhat human-like heads could be seen bobbing up and down with the waves at some distance from our boat, while one light-colored youngster, evidently this year's pup, swam to within 40 or 50 feet and watched us for a moment with his rather large dark hollow-like eyes. This, the Harbor Seal (Phoca vitulina concolor), is a so-called "hair" seal as contrasted against the "fur" seals of the Pacific coast. The Harbor Seal varies greatly in the color of his coat. Although very much at home in the water, these animals spend considerable time on land, and the mother must come ashore at the time her offspring is born. Seals feed on fishes, usually swallowing their prey under water. They remain active throughout the year.

Black Island is very small, less than half a mile long and under a quarter mile in width. The distance we had come from Mount Desert Island was somewhat more than a mile, but at its nearest point Black Island lies only a half mile from the larger island. The growth of spruce is dominant here, but other trees, such as white birch, balsam fir, arbor vitae, aspen, and mountain and striped maples are to be found. White pine is noticeably scarce. Crowberry (Empetrum nigrum) on the rocky slopes which reach to the sea and lichens, especially Cladonia and Usnea, are common plants, and they, along with the dominant spruces, lend a northern aspect to the vegetation here. Red-breasted Nuthatches were whipping the seeds from the spruce cones as we walked about the island.

A maze of runways made by field mice was evident in the open grassy stretches, and Mr. Lunt succeeded in collecting one of the animals which proved to be the common Short-tailed Meadow Mouse (Microtus pennsylvanicus pennsylvanicus). The Red-backed Mouse (Evotomys gapperi ochraceus) was seen but no specimen was secured. Both species were living and apparently thriving on this island, their runways extending to within a score of feet of the high tide marks, for it is probable that here they have very few natural enemies. Only the raptorial birds, rare in this region because of constant persecution, may be a factor in keeping down their numbers, for it is only in very cold winters that the water lying between Mt. Desert and Black Island freezes over allowing ready passage for foxes and other mammalian predators.

After a hurried survey of Black Island we cooked our dinner on the rocky shore and made preparations to leave. A loon was calling from well out in the bay, and a number of ducks could be seen resting on the water which now reflected the gold and crimson sunset colors. Suddenly, attracted by a kind of labored puffing or blowing sound, we spied a small school of porpoise swimming in the now placid water only a short distance away. With graceful rhythmic movements their smooth black glossy backs appeared above the sea, to disappear and reappear in a flowing progression which was beautiful to watch. Apparently they were in pursuit of the school fish which haunt our bays at this season of year, for at times they would all disappear for a moment or more before coming up to breathe. It is this essential surface breathing or puffing which has given them the local name of "puffers" or "puffing pigs."

The Harbor Porpoise (Phocaena phocaena) is a mammal which belongs to the order known as "cetaceans" - a group which spend their entire existence in the seas. Its valved nostrils, united in a single blowhole on the top of the head, aid the animal's breathing when it comes to the surface. Fish form the major item on the diet of this gregarious cetacean.

Like veritable nomads of the sea porpoises range widely, being found from the eastern coast of North America to the Mediterranean. Although often found in our harbors, they, unlike the seals, are entirely independent of the land, and their young, as in all cetaceans, are born at sea.

After watching the porpoises, we were soon on our way back to Mount Desert Island. The sunset colors, a glorious display of lavender and pink and gold, gradually faded and as the twilight deepened the brightest stars appeared above the dark spired horizon of Black Island. A few tardy gulls flew over our boat, their silhouettes making them appear black as crows against the sky.

- Temporary Park Naturalist