About the islets adjacent to the Tom Bay anchorage were great numbers of abandoned huts, and at some the size of the shell mounds and the compactness of the bottom layers indicated considerable antiquity. These mounds are principally composed of mussel and limpet shells, the latter predominating; and among the interstices were great numbers of insects and worms. There was one very old grass-covered mound near our anchorage, of which we made a thorough examination by digging cross-section trenches. Besides the usual shells, there were a few seal bones and sterna of birds, and at a depth of four feet from the surface we found a partly disintegrated bone spear-head, which was different in shape from any which we saw among the natives either before or subsequently. Instead of being rounded, it was flattened from side to side, like a very large arrow-head. In most of the other shell heaps which we examined, bones of the nutria (Myopotamus coypu) and of the otter (Lutra felina) were observed.
To the westward of our anchorage (i.e., in the large island of Madre de Dios) was a long narrow inlet, partly overhung with trees, which communicated by a shallow bar with a brackish lagoon of about thirty acres in extent. At low water there was only about three feet of water on the bar, and we could then see that the bottom was covered with huge white sessile barnacles (the "picos" of the Chilians), growing closely together. During the ebb and flood tides the current ran fiercely over this bar, so as to render it an exceedingly difficult matter to pull through the channel when the tide was adverse. This lagoon was a favourite haunt of the Magellan sea otter (Lutra felina), which is abundant in all these waters, but is very difficult to kill without the aid of dogs. Its "runs" are generally strewn with the shells of a large spiny crab (the Lithodes antarctica), which appears to form its principal food. I have seen an otter rise to the surface with one of these hideous crabs in its mouth, as unpalatable a morsel, one would think—for it is armed all over with strong spines—as a "knuckleduster." In the Alert, the great feat of sportsmanship was to shoot and bag an otter; for if the animal be not struck in the head, and killed outright at the first shot, it is almost certain to make a long dive, crawl up the beach in the shade of the overhanging bushes, and escape.
When exploring in a small boat the winding shores of this lagoon, we one day came upon a little sequestered cove, where there was a luxuriant growth of Desfontainea bushes, and on landing on the shingly beach we saw, by the way in which the larger stones had been moved aside, that the place had been used by the natives for hauling up their canoes. On walking through the long rank grass, which encroached on the beach, we tripped over some logs which seemed to have been arranged artificially, and we then discovered that we were at the extremity of a "portage," intended for conveying boats overland. On tracing it up, we found a sort of causeway leading into the forest; and after following it for about three hundred yards, we ascertained that we had crossed a narrow isthmus, of whose existence we were previously unaware, and had reached the shore of an arm of the sea (probably Delgado Bay), which communicates with the Trinidad Channel not many miles to the eastward of Port Henry. It was evident that by means of this "portage" the natives were able to proceed from Concepcion Channel, viâ Tom Bay, towards the outer coasts, without undertaking the much longer and more hazardous journey through the main channels round Point Brazo. The logs forming the "portage" were partly imbedded in the ground, and were arranged parallel to each other, like the sleepers of a railway, and at a distance of about two feet apart. There was, however, no appearance of the natives having recently visited the place. We had reason to believe that these "portages" were of frequent occurrence, and were largely used by the natives, and that it was owing to the facilities thus afforded them for crossing isthmuses and the necks of promontories that they were enabled to surprise sailing vessels at anchor, approaching them unobserved from the land-locked side of bays and inlets at a time when the attention of the sailors on "look-out" was naturally only directed towards the entrance of the harbour which had previously seemed to them to be untenanted. The "portages" are so concealed by a luxuriant growth of grass and brushwood that they readily escape observation.
The brackish lagoons, which are fed continuously by fresh-water streams, and receive an influx of sea-water while the flood tide is making, are a peculiar feature of this Patagonian archipelago, and we usually found that the outlets were excellent places for catching fish. Our fishing parties were in the habit of placing a "trammel" net across the outlet while the tide was ebbing, and in this way entrapped great quantities of mullet and mackerel; sometimes upwards of eighty, ranging in weight from two to eleven pounds per fish, being taken at one haul.
I collected some green flocculent matter from the surface of one of these lagoons, and found it to consist almost entirely of diatoms.
One fine day in April we noticed a great concourse of gulls and shags, attracted by a shoal of fish, in the pursuit of which they ventured unusually close to the ship. This gave us an opportunity of observing that the common brown gull of the channels, the female of L. dominicanus, behaves towards the male bird in many respects like a skua. No sooner would one of the "black-backed" (male) birds capture a fish, and rise from the surface, than he would be attacked by one of the brown birds, and chased vigorously about the harbour; the predatory bird not desisting from the pursuit until the coveted prize had been dropped by its rightful owner. This I noticed on more occasions than one. As a rule, however, the female was content to fish for herself. Several Dominican gulls in immature plumage were seen amongst the crowd, and were easily distinguished from the adults by the mottled brown plumage, and by the colour of the mandibles being green instead of orange, as in the males, and black as in the females. Now and then the whole flock of gulls and shags would rise on the wing, as they lost the run of the shoal of fish. They would then be directed to the new position of the shoal by the success of some straggling bird, when a general rush would be made to the new hunting ground. It was most amusing to witness the widely different fishing powers of the shags and gulls, and the consequently unequal competition in the struggle for food. The shag in flight, on observing a fish beneath him, at once checks himself by presenting the concave side of his wings to the direction in which he has been moving, and then, flapping legs foremost into the water, turns and dives; whereas the gull has first to settle himself carefully as he alights on the water, and has then to trust to the chance of some unsophisticated fish coming within reach of his bill. It was impossible to avoid noticing the mortified appearance of the poor gulls as they looked eagerly about, but yet caught only an odd fish, whilst their comrades, the shags, were enjoying abundant sport.
FUEGIAN "PORTAGE" FOR TRANSPORTING CANOES OVERLAND.
It is odd that the silly gull manages at all to survive in the struggle for existence. Here is another instance of his incapacity. A piece of meat, weighing a few ounces, drifted astern of the ship one day, and for its possession a struggle took place between a dominican gull and a brown hawk. The gull had picked up the meat, and was flying away with it in his bill, when he was pursued by the hawk—a much smaller bird—who made him drop it. Again the gull picked it up, and for a second time was compelled by the hawk to relinquish it. The latter now swooped down upon the tempting morsel, as it floated on the water, and seizing it with his claws, flew off rapidly into an adjoining thicket, to the edge of which he was followed by the disappointed gull.
Steamer-ducks (Tachyeres cinereus) are very abundant at Tom Bay, as indeed they are throughout all the western channels. Their English name, "steamer-duck," has reference to their habit of moving rapidly along the surface of the water by means of a paddling motion of the wings, and leaving a wake of foam which resembles, on a small scale, that of a paddle-steamer. A great deal has been written about these remarkable birds, and I shall not therefore attempt any general description, which at the best would only involve useless repetition. There are a few remarks about them, however, which I should like to make. Although aware of the careful investigations made by Dr. Cunningham in 1866-9, and his conclusion as to their being but one species, I have yet some reason to believe that the fliers and the non-flying birds which I have seen belong to two distinct species, and my impression is—though I am by no means sure—that the volant species frequents the fresh waters in the interior of Patagonia, and in the western channels is only represented by an odd straggler. Mr. Cox, of Talcahuano, who has travelled in Araucania and central Patagonia, mentions in his narrative, that in the fresh-water lakes of the latter district there are two different species of steamer-ducks, one of which possesses the power of flight. Immature specimens, although differing in the colour of the bill, and somewhat in plumage, from the adult birds, need not be confounded with a second species. The largest steamer-duck which I have come across weighed only 14 lbs., and although text books assign a much greater weight as the extreme limit, I think I am right in saying that few heavier birds are met with either in the Straits of Magellan or in the western channels. The female forms a low, oval-shaped nest of twigs, lined with a thick coating of down, and deposits therein six large cream-coloured eggs, 33⁄8 in. long, by 21⁄4 in. width. The nest is usually placed on the ground, at the foot of an old tree, some few yards from the beach, but in a place where the bush is almost impenetrable to a human being.