Aug. 23, 1888.J 



FOREST AND STREAM. 



89 



sheet of water, having the same general character as 

 Sunapee. It should be looked after. 



I have kept the camp supplied with bass, though I have 

 not taken any over two pounds. The largest were caught 

 by trolling with different artificial minnows. For shore 

 fishing I am using a 7oz. split bamboo, and have had good 

 success with various flies. My best evening cast is a 

 polka-dot (Henshall) for stretcher and a white-moth or 

 stone-fly for dropper. 



tSmall same is quite plenty about here, an old hen part- 

 ridge with her brood are always on the point near camp. 

 A pair of loons have nested near here for several years, 

 though they seem more shy each year. 



I receive the Forest and STREAM regularly, and no- 

 where is it more appreciated than in camp. "Sam 

 LoveFs Camps" strike me in a tender spot, knowing some- 

 thing of the locality of which they treat. Waltham. 



Sunapee Lake, Aug. 8. 



Black Bass in Lake Mahopac.— On Monday last we 

 saw eighteen fine black bass, which averaged over 31bs. 

 each, and were said to have been taken by a New York 

 angler in one day from Lake Mahopac, in Putnam county, 

 N. Y. The lake was stocked with these fish by Mr. E. G-. 

 Blackford five years ago, and if the fish really came from 

 that lake the fishing must be good there. We obtained 

 the information from a dealer who bought the fish, but 

 he could not furnish the name of the person who caught 

 them. 



FOOD OF THE FISHES OF THE MISSISSIPPI 

 VALLEY. 



BY PROF. S. A. FORBES. 

 [Read before tile American Fisheries Society.] 

 (Conti/miM from paae SS.) 

 PRINCIPAL ELEMENTS OK THE FOOD. 



AN analysis of the facts made with reference to the kinds 

 of fishes eating each of the principal articles in the 

 dietary of the class, and showing the relative importance of 

 these elements in the food of the various species, will have 

 its separate iuterest for us, especially as it will exhibit the 

 competitions of fishes for food, and also the nature and the 

 energy of the Eeatlaints imposed by fishes on the multiplica- 

 tion of their principal food species. 



The principal fish eaters among our fishes—those whose 

 average food in the adult age consists of seventy-five per 

 fient., or moi'e, of fishes— are the burbot, the pike-perch or 

 wall-eyed plke } the common pike or pickerel, the large- 

 mouthed black bass, the ehaulieLcat, the mild-cat, and the 

 BaiS. Possibly, also, the golden shad will be found strictly 

 Fehthyophagails, this being the case with the four speci- 

 mens which I studied, Those which take fishes in consid- 

 erable But moderate amount— the ratios ranging in my 

 Specimens from twenty-five to sixty-five per cent.— are the 

 war-moUth (ChainobryttUs), the blue-cheeked sunfish, the 

 grass pickerel, the dogfish, the spotted cat and the small 

 miller's thumb. The wmite and the striped bass, the com- 

 mon perch, the remaining sii.nfishes (those With smaller 

 mouths), the rock bass and the croppies take but few fishes, 

 these making, according to my observations, not less than 

 five not more than twenty-five per cent, of their food. 

 Those which never capture living Qshes", Of, at most, to a 

 merely trivial extent, are the white perch or sheepshead, 

 the gizzard shad, the suckers and the shovelfish among 

 the larger species; and the darters, the brook silversides, 

 the stickleback, the mud minnows, the top minnows, the 

 stone-cats and the common minnows generally among the 

 smaller kinds. Our eight specimens or the toothed herring 

 had taken no fishes whatever; while our nineteen examples 

 of the pirate perch had eaten only two per cent. 



Rough-scaled fishes with spiny fins' were eaten by the 

 miller's thumb, the common pike, the wall-eyed pike, the 

 large-mouthed black bass, the croppies, the dogfish, the 

 common perch, the burbot, the bullhead, the common sun- 

 fish (Lepomis pallidas), the small-mouthed black bass, the 

 grass pickerel, the gar, and the mudcat (Leptops). Among 

 these, the common perch and the sunfishes were most 

 frequently takeu— doubtless owing to their greater relative 

 abundance— the perch occurring in the food of the burbot, 

 the large-mouthed black bass and the bullhead; and the 

 Buufishes in both species of wall-eyed pike, the common 

 pike, the gars, pickerel, bullheads, and mudcat. Black bass 

 Were taken from the commonpike (Esox), the wall-eyed pike 

 (Stizostedion), and the gar. Croppie and rock bass I recog- 

 nized only inthe pike. Even the catfishes with their stout, 

 sharp and poisoned spines were more frequently eaten than 

 would have been expected— taken, according to my notes, by 

 the wall-eyed pike, both black bass, and a fellow species of 

 the family, the goujon or mudcat. 



The soft-finned fishes were not ver} r much more abundant, 

 on the whole, in the stomachs of other soecies, than those 

 with ctenoid scales, spiny fins, and other defensive structures, 

 an unexpected circumstance which I cannot at present ex- 

 plain, because I do not know whether it expresses a normal 

 and fixed relation, or whether it may not be due to human 

 interference. 



Only the catflshes seem to have acquired defensive struc- 

 tures equal to their protection, the predatory apparatus of 

 the carnivorous fishes having otherwise outrun in develop- 

 ment the protective armor of the best-defended species. 



Among the soft-finned species the most valuable as food 

 for other fishes is the gizzard shad, Dorosoma, this single 

 fish being about twice as common in adults as all the min- 

 now family taken together. It made fortv per cent, of the 

 food of the wall-eyed pike; a third that of* the black bass; 

 nearly half that of the common pike or "pickerel" two-thirds 

 that of the four specimens of golden shad examined; and a 

 third of the food of the gars. The only other fishes in 

 whose stomachs it was recognized were the yellow cat, 

 Ictalurvs natalis, and young white bass, Roccus. It thus 

 seems to be the especial food of the large game fishes and 

 other particularly predaceous kinds. 



The minnow family (Oyprinidse) are in our waters especi- 

 ally appropriated to the support of the half-grown game 

 fishes, and the smaller carnivorous kind. They were found 

 in the wall-eyed pike, the perch, the black bass, the blue- 

 cheeked sunfish, the croppie, the pirate perch, the pike, the 

 little pickerel, the chub minnow, the yellow cat. the mud 

 cat, the dogfish, and the gar. 



Suckers, Catostomatidse, I determined onlv from the pike, 

 the sheepshead, the blue-cheeked sunfish '(cyanellus) the 

 yellow cat, and the dogfish Amia. Buffalo and carp oc- 

 curred in the pike, the dogfish, and the above sunfish. 



The ponds and muddy streams of the Mississippi Valley 

 are the native home of mollusks of remarkable variety and 

 number, and these form a feature of the fauna of the region 

 not less conspicuous and important than its leading groups 

 of fishes. We might, therefore, reasonably expect to find 

 these dominant groups connected by the food relation; and 

 consistently with this expectation, we observe that the 

 sheepshead, the catflshes, the suckers, and the dogfish, find 

 an important part of tbevr food in the molluscan forms 



abundant in the waters which they themselves most fre- 

 quent. The class as a whole makes about; one-fourth of the 

 food of the dogfish and the sheepshead— taking the latter as 

 they come, half-grown and adults together— about half that 

 of the cylindrical suckers— rising to sixty per cent, in the 

 red horse— and a considerable ratio (fourteen to sixteen per 

 cent.) of the food of the perch, the common catflshes (Amiu- 

 rus and Tetaturus), the small-mouthed sunfishes, the top 

 minnows, and the suiner (Notemigonus). Notwithstanding 

 the abundance of the fresh-water clams or river mussels 

 (Uuio and Anodonta), only a single river fish is especially 

 adapted to their destruction, viz., the white perch or sheeps- 

 head; and this species derives, on the whole, a larger part of 

 its food from univalve than from bivalve mollusks, the 

 former eaten especially by half-grown specimens, and the 

 latter being the chief dependence of the adults. The ability 

 of the catflshes to tear the less powerful clams from their 

 shells have been already mentioned. Large clams were 

 eaten freely by the full-grown sheepshead— those enormous 

 and powerful pharyngeal jaws with their solid pavement 

 teeth are especially adapted to crushing the shells of 

 mollusks— and by the bullheads (Amiurus), especially 

 the marbled cat. The small and thin-shelled Sphaeriums 

 are much more frequent, objects in the food of molluak- 

 eating fishes than are the Unios. This genus alone made 

 twenty-nine per cent, of the food of 107 specimens of the 

 sucker family, and nineteen per cent, of that of a dozen dog- 

 fishes. A mong the suckers it was eaten greedily by both the 

 cylindrical and the deep-bodied species, although somewhat 

 more freely by the former. Even the river carp, with its 

 weak pharyngeal jaws and delicate teeth, finds these suffi- 

 cient to crush the shells of Spha'rium, and our nineteen 

 specimens had obtained about one-fourth of their food from 

 this genus. Besides the above families, smaller quantities 

 of the bivalve mollusks occurred in the food of one of the 

 sunfishes (Lepomis pallidas), and— doubtless by accident 

 only— jn the gizzard shad. The gasteropod mollusks (snails 

 of various descriptions) were more abundant than bivalve 

 forms in the sheepshead, sunfish and all the smaller fishes 

 which feed upon Molluska, but less abundant iu the suckers 

 and the catflshes. In the sheepshead they made one-fifth of 

 the food of the twenty-five specimens examined, but the 

 greater part of these had not yet passed the insectivorous 

 stage, this being much longer continued in the sheepshead 

 than in many other fishes. A few of these univalve Mol- 

 luska occurred in the food of the common perch and in cer- 

 tain species of sunfishes— especially the superabundant 

 bream or pumpkin-seed. They made fifteen percent, of the 

 food of the top minnows, and occurred in smaller quantities 

 among the dart ?rs. little pickerel , the mud minnows and the 

 cyprinoids. Tne heavier river snails, Vivapara and Me- 

 lantho, were eaten especially by the cylindrical suc kers and 

 the catfishes. The delicate pond snails (Succinea, Lemna 

 and Physa) were taken chiefly by the smaller mollusk-eating 

 fishes— a few of them also by the catflshes and the suckers. 



It is from the class of insects that adult fishes derive the 

 most important portion of their food; and, taken as a whole, 

 this class furnishes 38 per cent, of the food of all which I 

 examined. The principal insectivorous fishes are the smaller 

 species, whose size and food structures, when adult, unfit 

 them for the capture of Entomostraca and yet do not bring 

 them within reach of fishes or Mollusca. Some of these 

 fishes have peculiar habits which render them especially de- 

 pendent upon insect life— the. little minnow, Phenacobius, 

 for example, which, according to my studies, makes nearly 

 all its food (98 per cent.) from insects found under stones in 

 running water. Next are the pirate perch, Aphredoderus 

 (91 per cent.), then the darters (87 per cent.), the croppies (78 

 per cent.), half-grown sheepshead (71 per cent,), the shovel 

 fish (59 per cent.), the chub minnow, Semotilus (56 per cent.), 

 the black warrior sunfish (Cbaeuobrytus) and the brook sil- 

 versides each 5i per cent. , and the rock bass and the cyprinoid 

 genus Notropis each 52 per cent. 



Those which take few insects or none are mostly the mud 

 feeders, and theichthyophageous species Amia (the dogfish) 

 being the only exception to this general statement. Thus 

 wc find insects wholly or nearly absent from the adult diet- 

 ary of the burbot, the pike, the gar. the black bass, the wall- 

 eyed pike, and the great river catfish, and from that of the 

 hickory shad and the mud-eating minnows (the shiner, the 

 fathead, etc.). It is to be remembered, however, that the 

 larger fishes all go through an insectivorous stage, whether 

 then* food when adult be almost wholly other fishes, as with 

 the gar and the pike, or mollusks, as with the sheepshead. 

 The mud feeders, however, seem not to pass through this 

 stage, but to adopt the limophagous habit as soon as they 

 cease to depend upon Entomostraca. 



Terrestrial insects, dropping into the water accidentally, 

 or swept in by rains, are evidently diligently sought and 

 largely depended upon by sevei-al species, such as the pirate 

 perch, the brook minnow, the top minnows or killifishes 

 (Cyprinodontidcc), the toothed herring and several cyprin- 

 oids (Semotilus, Pbncphalcs and Notropts). 



Among aquatic insects, minute, slender, dipterous larvae 

 are of remarkable importance, making, in fact, nearly one- 

 twelfth of the food of all the fishes studied. They amounted 

 to about one-third the food in fishes as large and important 

 as the red horse and the river carp, and made nearly one- 

 fourth that of fifty-one buffalo fishes. They appear further 

 in considerable qtiantity in the food of a number of the 

 minnow family (Notropts, Pimephales, etc.), which habit- 

 ually frequent the swift water of stony streams. Aquatic 

 beetles and larvse, notwithstanding the abundance of some 

 of the forms, occurred in only insignificant ratios, but were 

 taken by fifty-six specimens. The adult surface beetles, 

 whose zig-zag darting swarms no one can have failed to 

 notice, were not once encountered iu my studies. 



The almost equally well-known slender water-skippers 

 seem also completely protected by their habits and activity 

 from capture by fishes, only one occurring in the food of all 

 our specimens. 



It is from the order Neuroptera that fishes draw a larger 

 part of their food than from any other single insect group. 

 In fact nearly one-sixth of the entire amount of food con- 

 sumed by all the fishes examined by me consisted of aquatic 

 larvse of "this order, the greater part of them larvae of day 

 flies. These Neuroptera larvse were eaten especially by the 

 miller's thumbs, the sheepshead, the white and striped 'bass, 

 the common perch, thirteen species of the darters, both the 

 black bass, seveu of the sunfishes, the rock bass and the 

 croppies, the pirate perch, the brook silversides, the stickle- 

 backs, the mud minnow, three top minnows, the gizzard 

 shad, the toothed herring, twelve species each of the true 

 minnow family and of the suckers and buffalo, five catfishes, 

 the dogfish and the shovelfish— seventy species out of the 

 eighty-seven which I studied. 



Of the four principal classes of the food of fishes, viz., 

 fishes, mollusks, insects aud Crustacea, the latter stand 

 third in importance according to my observations, mollusks 

 alone being inferior to them. The insect larva? should be 

 more abundant in the food of fresh-water fishes than are 

 crustaceans is a somewhat unexpected fact, but while the 

 former make about 25 per cent, of the food of our entire col- 

 lection, the crustaceans amount to only 14 per cent. Cray- 

 fishes made about a sixth of the food of the burbot, about 

 a tenth that of the common perch, a fourth that of half a 

 dozen gars and not far from a third that of the black bass*, 

 the dogfish and our four rock bass. Young crayfishes ap 

 peared quite frequently in some of the larger minnows 

 (SemotUus and Hybopsis), and also in catflshes, especially 

 the. pond and river bullheads, 'averaging nearly 15 percent, 

 of the entire food of the two most abundant species. 



* Our specimens— especially of the small-mouthed black base 

 —were too few in number to make this average reliable. 



The minute crustaceans commly Tgrouped as Entomos- 

 traca are a much more important element. Among full 

 grown fishes I find them especially important in the shovel- 

 fish— where they made two-thirds of the food of the speci- 

 mens studied— and in the common lake herring. Among 

 the sunfishes at large they were present in only insignificant 

 ratio; but the croppies, distinguished by long and numerous 

 rakers on the anterior gill, had derived about a tenth of 

 their food from these minute crustaceans. In the early 

 spring, especially when the back waters of the streams are 

 filled with Entomostraca, the stomachs of these fishes are 

 often distended with the commonest forms. Ten per cent, 

 of the food of the sucker family consisted of them, mostly 

 taken by the deep-bodied species, in which they made a 

 fourth or a fifth of the entire food. This fact is explained, 

 it will be remembered, by the relative long, slender and 

 numerous gill rakers of these fishes. Large river buffalo 

 were occasionally crammed with the smallest of these Ento- 

 mostraca, only l-25in. in length. 



I have several times remarked the peculiar importance of 

 Kutomostraca to the shovelfish— one of the largest of our 

 f resh-water animals— a fact accounted for by the remarkable 

 branchial strainer of this species, probably the most efficient 

 apparatus of its kind known to the ichthyologist. Here, 

 again, the smallest forms were the most abundant. 



Probably to those accustomed to the abundance of true 

 worms in marine situations, no feature of the poverty of 

 fresh-water life will be more striking than the small number 

 of this sub-kingdom occurring in the course of miscellan- 

 eous aquatic collections in the interior. Similarly, we 

 notice that in the food of fishes the occurrence of Vermes is 

 so rarely noticed that they might be left out of account 

 entirely without appreciably affecting any of the important 

 ratios. Catfishes alone seem purposely to eat leeches, these 

 occurring in nine specimens of three, different species of this 

 family, and also in one common sucker and in a single 

 shovelfish. One of the fresh water sponges (Spongilla) had 

 been eaten in considerable quantities by two examples of 

 the spotted cat taken in September, bttt this element was 

 not encountered elsewhere in my studies. 



That the minutest and simplest of all the animal forms, 

 far too small for the eye of a fish to see without a micro- 

 scope, should have been recognized in the food of seventeen 

 species of fishes is, of course, to be explained only as an in- 

 cident of the feeding habit. It is possible, however, that 

 these Protozoa, where especially abundant, may be recog- 

 nized in the mass by the delicate sensory structures of the 

 fish; and they seem in most cades to have been taken with 

 mud and slime, rich in organic substances. As most of 

 them are extremely perishable, and can scarcely leave a 

 trace, a few seconds after immersion in the gastric juices of 

 the fish, it is probable that they contribute much more gen- 

 erally than our observations indicate to the food of some 

 fishes, especially to those which feed upon the bottom. 



Young suckers under 6in. in length clearly take them pur- 

 posely, substituting Ihem in great part for the Entomo- 

 straca taken by other fishes of their size and age. 



1 detected Protozoa in the food of several genera of 

 Cyprinidro, in the young of buffalo, the river carp, the chub 

 sucker, the red-horse, the stone roller, iu the common 

 sucker, in a single gizzard shad, in a stone-cat and in a top 

 minnow. 



The only scavenger fishes of our collection were three spe- 

 cies of the common catfishes; the spotted cat, the yellow cat, 

 and the marbled cat— all of which had eaten dead animal 

 matter, including pieces of fish, ham, mice, kittens, and the 

 like. A single large-mouthed black bass had likewise eaten 

 food of this description. 



Considering the wealth of vegetation accessible to aqua- 

 tic animals, and the fact that few others strictly aquatic 

 kinds have the vegetarian habit, it is indeed remarkable 

 that fishes draw from plants an unimportant part of their 

 diet. Taking our nine hundred species together, the vege- 

 tation eaten by them certainly would have amounted to less 

 than ten per cent, of their entire food, and excluding vege- 

 table objects apparently taken by chance, it probably would 

 not reach five per cent. 



The greatest vegetarians are among the minnow family. 

 Counting each genus as a unit, I find that the family as a 

 whole obtained from plants about twenty-three per cent, of 

 its food. The little Phenacobius, already reported as 

 strictly insectivorous, was the only one studied in which 

 vegetation can scarcely be said to occur. 



Certain of the sunfishes evidently take plant food pur- 

 posely on occasion, this makiug, for example, nearly atenth 

 of the food of forty-seven specimens of Lepomis. Among 

 the larger fishes, the principal vegetarians are the gizzard 

 shad, in which this element was reckoued at about a third, 

 taken, however, not separately, but with quantities of mud. 

 A considerable part of the vegetation here included, con- 

 sisted of distillery slops obtained near towns. The buffalo 

 fishes are likewise largely vegetarians, more than a fourth 

 of their food coming from the vegetable kingdom; about a 

 third of this in our specimens being refuse from distilleries. 

 Vegetation made a tenth of the food of the larger genera of 

 catfishes (Amiurus and Ictalurus)— some of it "distillery 

 refuse— and nearly as large a ratio of the great Polyodou. 



Not infrequently, terrestrial vegetable rubbish— seeds of 

 grasses, leaves of plants, and similar matter— was taken in 

 quantity to make it certain that its appropriation was not 

 ac cidental. The principal mud-eating fishes are the gizzard 

 shad, the common shiner, and certain genera of minnows 

 with elongate intestines aud cultrate pharyngeal teeth. 

 Much mud was also taken by the cylindrical members of the 

 sucker family, but apparently as an incident to their search 

 for mollusks. 



I cannot attempt to discuss the practical bearing of the 

 mass of data here presented, or of the much greater number 

 which I have withheld, partly because the time is lack- 

 ing, and partly because I know too little of practical fish- 

 culture; and I will merely call attention to a few illustrative 

 points which have occurred to me in writiug. 



It would seem that the fact that all young fishes compete, 

 at first, for food, must have important 'practical result tend- 

 ing in various directions. It is probable that all fishes which 

 are not especially adapted to the food requirements of the 

 more valuable fishes are. hurtful to them, because they limit 

 the food available for their young. It seems possible that 

 even the food species of the predaceous fishes may multiply 

 to an extent injurious to the latter, since both robber and 

 prey compete while young for the same elements of food. It 

 would seem entirely likely that large fishes, like the shovel- 

 fish, which destroy when adult immense quanties of the 

 proper food of the young, must be reckoned injurious. 



Again, it is evident that the fishes most desirable as food 

 for other kinds are those whose own food is not eaten by 

 valuable species, but exists in practically inexhaustible sup- 

 plies. The gizzard shad and the mud-feeding minnows are 

 examples of this sort; while the red-horse and other cylindri- 

 cal suckers answer the purpose almost equally well, since no 

 valuable fishes feed upon mollusks (especially preferred by 

 the suckers), and these are among the most abundant ani- 

 mals in our western streams. The fact that they have like- 

 wise adapted themselves to civilization, so far at least as to 

 relish distillery slops, is, perhaps, an additional recommen- 

 dation from this point of view. 



The smaller catfishes, being practically omnivorous, are 

 the rivals of every other kind; and being almost perfectly 

 protected from capture by their stout, sharp, poisoned spines 

 they contribute little to the food supply of other fishes. The 

 common sunfishes are almost equally worthless and injuri- 

 ous from this point of view. 



I need scarcely say that the fishculturist should examine 

 I the waters in which young fishes are planted, in order to 



