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Lower South Bay of Oneida Lake looking west from Short Point.-This shows a transition from the shallow bowldery point in the foreground, with its scanty vegetation of water willow, to the protected bay in the background with its sandy or clay bottom and its abundant vegetation of cattail, willow, lake bulrush, water lilies, pickerel weed, and a number of pond weeds. In general, bowlders and gravel cover the floor of exposed points, while shallow bays have sandy bottoms and those of the deeper bays and the main floor of the pond are composed of clay and mud. By far the greater part of plant and animal life of the lake is found where the water is less than six feet deep; below a depth of twelve feet there is little or no vegetation
Invertebrates yielded by approximately 768 square inches of mud bottom under ten feet of water, illustrating the marked falling off in numbers with increased depth, especially of mollusks. Fingernail clams (Pisidium), snail shells (Amnicola), the larvae of midges (Chironomus), and the nymphs of May flies (Hexagenia) are the principal animals; the caddis fly cases (on the left) are practically all empty. The larvæ are of great importance in the food supply of most of the larger species in the lake including other nymphs and larvæ; the May flies are eaten especially by pickerel. The mussels which were taken in this area are not shown in the photograph
STUDIES IN AQUICULTURE OR FRESH-WATER FARMING 487
resented by twenty-five classes or higher groups, forming a microcosm of large size and great variety.
culturists. It may be said without fear of successful contradiction that when the flora is insufficient or wanting the animal life will be correspondingly rare or absent. There is also another source of food supply which has received little attention by American students of fish culture. This is the fine covering of the bottom which Dr. C. G. Joh. Petersen, the Danish biologist and fish culturist, has called dust-fine detritus. This material is composed of the finely comminuted fragments of vegetation, together with diatoms, desmids, and other biotic material, and is largely used by many of the invertebrate animals and by some fish as food. It is believed by Petersen and other Danish workers on fish food problems that this is of greater value than the plankton organisms which are so abundant in most of our fresh-water lakes. It is known that marine animals use it to a large extent but its proportionate use by the inhabitants of fresh-water ponds and streams is not definitely known. That it is of some, if not great value, is highly probable.
When we consider the sources of food of the invertebrate population of this bay, as well as other bodies of fresh water, we find that the herbivorous animals, those that live on plants and detritus, greatly predominate over the animals that have carnivorous habits and prey upon the other animals present. Dividing the population of the area of Lower South Bay into herbivorous and carnivorous animals we find the astounding result of 7743 million individuals that feed on plants and detritus against 23 million individuals that are carnivorous. In per cents this means that the carnivorous animals make up but 310 of 1 per cent of the entire population. This fact is of great importance, for the herbivorous animals are producers of fish food and the carnivorous animals are consumers of fish food. While the carnivorous animals are of some food value to fish, it is the great mass of herbivorous animals that is transforming plants and débris into animal flesh, that forms the principal food supply of our food and game fishes.
One of the most interesting features of the Oneida Lake investigation was the variety of animal life found on the bottom of Lower South Bay. Seven of the ten phyla of invertebrate animals (the Protozoa are not considered for obvious reasons) are rep
The mollusks, snails and clams, and the insects are about equal in number of species, the mollusks forming 35 per cent of the entire number of species represented. When the number of individuals of the two groups, mollusks and the other associated animals, are compared, it is found that the former are 30 per cent greater in number. This preponderance of mollusks over associated animals has also been noted by students conducting marine investigations. Of the 7766 million individuals of invertebrate animals calculated to be present on the bottom of Lower South Bay and vicinity, 4704 million are mollusks and 3062 million are associated animals. The mollusks or shellfish form a large part of the food of such valuable fish as the sturgeon, sheepshead, suckers, red horse, whitefish, pumpkin seed, and bullheads. Of the 225 different species of fish inhabiting the waters of Illinois and New York, 46 or about one fifth are eaters of shellfish to a greater or less degree. Of all the classes of food, insects are by far the most valuable, about 40 per cent of the food of all fishes being of this group of animals.
One of the results hoped for in the Oneida Lake investigations was a knowledge of the size of the fish fauna that the natural food of the lake could support. To find this it was necessary to know the amount of food eaten in a period of time, as in twenty-four hours. Studies on marine fish (notably the plaice) indicated that the digestive canal was emptied once in twenty-four hours. These marine fish, however, are not strictly comparable with the fresh-water fish in this respect. In 1917, a study of fish caught in trap nets and allowed to remain in these nets for a period of 24, 48, and 72 hours, indicated that the digestive tract might be emptied in about 24 hours. Of the fish caught, 50 per cent had full stomachs in the 24-hour interval, 13 per cent in the 48-hour interval, and all were empty in the 72-hour interval.
It is known that the digestive powers of a fish become slower in cold weather, and it is probable that between November and March fish eat about two thirds or less of the amount of food eaten during warmer months in spring, summer, and fall. In the examination of the stomach and intestines of Oneida Lake fish it was found that on the
average a fish with a full stomach contained about 115 invertebrate animals. If we assume that this amount is a daily average, and that fish eat this amount for nine months of the year, then the invertebrate animal life on the bottom of the 1164 acres examined in Lower South Bay and vicinity is calculated to furnish food for 337,500 bottom-feeding fish. Predatory fish like the pike perch consume a large number of fish. By using data from Illinois and New York it was estimated that a single fish of this species will eat 250 to 600 small fish in a year. When we remember that there are hundreds of individuals of the pike perch, as well as other predatory fish, in Oneida Lake, it is at once realized that the number of small fish in this lake must be very great to supply these fish with food. It also follows that a large number of invertebrate animals as well as an abundance of vegetation for the smaller animals to feed upon is necessary to provide food for these small fish. It has been shown by these investigations that Oneida Lake meets, in full measure, all of the conditions and requirements favorable to fish and these provide the essentials for a large and varied population of food and game fish.
The studies carried on at Oneida Lake and elsewhere have shown that there are great possibilities in the production of animal life of a useful character to man from the freshwater streams and bodies of water in our country. The recognition of the value of shellfish and other associated animals which
form the food of fish, will lead in the not distant future to the artificial introduction of these animals, as well as needed plants, into waters where they were previously wanting or insufficient in number. If the environment and other factors are favorable there will be no insurmountable difficulties to hinder this procedure. The fresh waters will be cultivated to the extent that the land areas are now worked, as has been the case in parts of Europe, where ponds have been made artificially and stocked with fishes and their food. Food in the form of plants, shellfish, insects, crustaceans, and the like, will be introduced where needed before the fish are planted, paralleling in a way the preparation of the land before the crop is sown. Given a species of fish whose life history and natural history are known, it is comparatively easy to prepare the right kind of habitat and the natural and suitable food. Thus in the course of time we may hope to have a flourishing water culture or aquiculture, so that our streams and lakes may be made productive to the same relative degree that the fields and forests now are. Water culture has the additional advantage of affording healthful recreation to a degree not shared by any branch of agriculture.1
1 Those who may be interested in the details of the studies carried out on Oneida Lake are referred to the following technical papers, published by the New York State College of Forestry at Syracuse University, N. Y.: Publication No. 4. The Relation of Mollusks to Fish in Oneida Lake. 1916; Publication No. 9. The Productivity of Invertebrate Fish Food on the Bottom of Oneida Lake, with Special Reference to Mollusks. 1918; Circular No. 21. The Relation of Shellfish to Fish in Oneida Lake. 1918.
Between Dunham and Frenchman islands in the distance lies a sandy shoal where the water is for the most part less than five feet deep. On this hard, smooth bottom a greater average number of animals was found than in any other part of the lake. This photograph of Oneida Lake is taken from Norcross Point looking northwest
Quest of the Ancestry of Man
AWO institutions have recently been founded to investigate the problems of man's antiquity, human ancestry, and cultural development-the Institut de Paléontologie Humaine, founded in Paris in 1910, and the Galton Society, recently established in the United States with rooms at the American Museum of Natural History.
In founding the Institut de Paléontologie Humaine in 1910, the Prince of Monaco addressed the Minister of Public Instruction as follows: 1
"In the course of my laborious life I have often regretted that in the intellectual activities of our epoch a more important place has not been given to the study of the mystery that shrouds the origin of man. The more my mind has been stimulated by scientific study, the more ardently I have desired to see established on methodie foundations the investigations necessary to uncover the fugitive traces left by our ancestors in the bosom of the earth during an incalculable succession of centuries. And I thought that the philosophy and ethics of human society would be less uncertain in view of the history of past generations, written in their own remains.
"Therefore, when I had finished establishing the pursuit of Oceanography in the institutions of Monaco and of Paris, I devoted a part of my effort to the search for means which would further the development of Human Palæontology. And, after the foundation of the Museum of Anthropology of Monaco (Musée anthropologique), which was soon enriched with veritable treasures; after the publication of the marvels found in the caverns of Spain; I resolved to establish near some university center a strong foundation for studies based on methodic excavation. Immediately I made choice of the capital of France, where my earlier foundation, the Oceanographic Institute, had already been so largely developed.
"I have selected a site for the building of the Institute of Human Palæontology, and I have selected the first scientists who will
1 Institut de Paléontologie Humaine, Fondation Albert 1. Prince de Monaco. Statuts, p. 5. Letter of His Serene Highness the Prince of Monaco to the Minister of Public Instruction.
direct its scientific undertakings; I have also named an Administrative Council who will control its financial resources.
"I must add that I do not limit the patrimony of the new institute to the building to be erected at Paris: the collections which I have installed at Monaco, although destined to remain there so long as my wishes for their conservation are followed, will become a conditional donation on my part to the Institute of Human Palæontology, to which I have given, for a working endowment, the sum of sixteen hundred thousand franes.
"Being anxious that this foundation should survive me under the most favorable conditions for the advancement of Science, I make request to the French Government to recognize it as a public utility and to approve its statutes."
The Institute is directed, from the technical and scientific side, by a "Comité de Perfectionnement" (Committee of Development), composed of twelve members, either French or foreigners. The members are chosen without distinction of nationality and without observing any especial proportion in the representation of different countries, from among those scientists best qualified to serve. It is to this body that Henry Fairfield Osborn of the American Museum has recently been elected.
The Founder, and, after his decease, the Comité de Perfectionnement, designateseither among its members or outside thema French scientist to whom it delegates a portion of its powers, and who has the title of Technical Director of the Institute. He receives compensation on account of his responsibilities. The Director is appointed for three years at most and with the possibility of reappointment. The Administrative Council may call upon the Director to attend any of their meetings in an advisory capacity. This office has been held since the beginning by Marcellin Boule, who is also head of the paleontology of the Museum of the Jardin des Plantes, Paris.
The Comité de Perfectionnement fixes the program of work to be undertaken upon the recommendations of the Technical Director, presents to the Administrative Council those scientists who may be attached to the Institute and who will form its scientific person