December 1948

VOL. XXVII DECEMBER, 1948 NO. 12

THE MONTHLY PUBLICATION OF THE YOSEMITE NATURALIST DIVISION AND THE YOSEMITE NATURAL HISTORY ASSOCIATION, INC.

C. P. Russell, Superintendent D. E. McHenry, Park Naturalist H. C. Parker, Assoc. Park Naturalist H. N. McIntyre, Asst. Park Naturalist

VOL. XXVII DECEMBER, 1948 NO. THE NATIVE FISH FAUNA OF YOSEMITE NATIONAL PARK AND ITS PRESERVATION'

By Carl L. Hubbs, Scripps Institution of Oceanography and Orthello L. Wallis, Ranger Naturalist, 1948 Except for some studies and stories included in "Yosemite Ranger Naturalist Manual " on the trout, the fish fauna of YO (1929). The fourth and most important was a pamphlet semite National Park has been made known in only four publications. entitled "Fishes of Yosemite NaThe first, a book by J. M. Hutchings, tional Park." It was prepared by "In the Heart of the Sierras" (1886), Willis A. Evans, as a result of ob contained a very brief statement on serving as Ranger Naturalist in 1941, observations that he made while the fish life of the Merced River. The second was a chapter on "The and it was issued as Volume XXIII, Fishes of Yosemite National Park," Number 1, of Yosemite Nature Notes by Barton Warren Evermann, in (1944). The paucity of reports on the fishes of Yosemite contrasts glaringly with the thorough treatment of the Yosemite National Park" (1921). The terrestrial vertebrates and reflects third was a brief treatise on "Fish the limited study that has been made and Fishing in Yosemite National of the underwater life in this and Park," written by H. C. Bryant and other National Parks.

PRESERVATION OF THE NATIVE FISH FAUNA

The aquatic life of the National erally allowed and is frequently enParks has been much neglected, not couraged. Only indigenous species only in research but also in the naare regarded as proper in the terrestrial communities, and exotics are eradicated wherever possible. In contrast, exotic fishes, especially trouts, have frequently been stocked and maintained to provide sport in Park waters. The introduced species no doubt greatly disturb natural conditions in several ways : disease organisms may be introduced, restial communities, and exotics are 1937, pp. 395-397; Hubbs, 1940, pp. eradicated wherever possible. In 3-4; Cahalane, 1947, pp. 69-70; contrast, exotic fishes, especially Hubbs and Lagler, 1949, pp. 98-99). trouts, have frequently been stocked The animal life above the water surand maintained to provide sport faces in the Parks has traditionally in Park waters. The introduced been treated as a sacred trust, to be species no doubt greatly disturb natpreserved in strictly natural condiural conditions in several ways : diction. That which lives below the ease organisms may be introduced, water surfaces, in contrast, has camto infect native species as well as monly been managed as a recreathe exotics; some introduced forms tional asset. Hunting of course is hybridize with the indigenous ones; strictly prohibited, but fishing is generally allowed and is frequently encouraged. Only indigenous species through competition or predation, the tContribution from the Scripps Institution Oceanography, New Series, No. 394.

native fishes and invertebrates may cept on the floor of Yosemite Valley be depleted or even exterminated, the rainbow trout is maintaining Fishing in itself disturbs the balance abundance in competition with the of nature. brown trout. Even if all stocking

Consistency would seem to de brown trout should be abandoned. mand the strict preservation of all this European species, which is particularly the native aquatic life as well as all resistant to depletion, might the native terrestrial life of the Parks, continue to exist indefinitely in the but such a policy could hardly be established now. Sport fishing has become a vested right of the Park visitors and is one of the outstanding recreational assets. Furthermore, legislation is involved. After considering this conflict in policy and practice, the Park Service has reached a realistic compromise policy, which calls for the preservation of the native aquatic life where it still exists, but which permits stocking of fish and allows fishing for sport where the natural balance has already been greatly disturbed (see statement of policy in the current edition of "Fishes of Yosemite National Park"). We urge a trend toward a more preservationist policy wherever this is practicable.

So far as the native fish life is concerned, there seems to be little fear that sport fishing will further greatly modify the natural conditions in Yosemite National Park. The native stock of rainbow trout has no doubt been modified by hybridization with introduced stocks, representing different races of the same species, or has been more or less completely replaced by the exotic races; the original characteristics of the local form of the Merced River can probably never be learned. The only other native species now of wide occurrence in the Park, the Sacramento sucker, is maintaining itself, despite the predation that must be exerted against it by trout. Such predation may be effected chiefly by the now brown trout, which is usually more piscivorous than the other trouts. Except on the floor of Yosemite Valley, the rainbow trout is maintaining abundance in competition with the brown trout. Even if all stocking of brown trout should be abandoned, this European species, which is particularly resistant to depletion, might continue to exist indefinitely in the Valley. The other native fishes, the three minnows and one sculpin, appear occur naturally in the Park only in the lower stretches of the Merced River. They may ascend to the Power dam in the Merced Canyon but if so, they are blocked by the obstacle from reaching the increasingly more habitable waters of Yosemite Valley. They may originally have transgressed the turbid waters of the Canyon at favorable times, to populate the relatively quiet waters of the Valley, but if so, they were probably eliminated there by the brown trout or by the floods. Re-entry into the Valley would have been prevented by the dam.

More natural conditions for fish life in the Merced River and other Yosemite waters might be restored but only by such measures as: (1) cessation of all further stocking of the exotic brown trout (in line with the present policy and program of the State division of Fish and Game, which has restricted the propagation of this species, regarded has been more or less completely re tirely to National Park waters); (2) placed by the exotic races; the orig Increased stocking of rainbow trout inal characteristics of the local form the Valley floor, perhaps using large of the Merced River can probably er fingerlings, or even yearlings or never be learned. The only other na adults; (3) Propagation of the rainbow Live species now of wide occurrence trout of Yosemite Park waters, in the Park, the Sacramento sucker, or of other nearby Sierra Nevada is maintaining itself, despite the waters, rather than those of distant predation that must be exerted regions, in order to maintain stock against it by trout. Such predation as nearly like the original as could may be effected chiefly by the now be possible; (4) Lessening or removal of fishing restrictions on brown trout, or its depletion in Valley by other means; (5) Protecting the rainbow trout, particularly in the Valley; (6) Removal of the power dam, to permit the natural movement of rainbow trout and other native species from the Canyon into the Valley. These measures could be invoked in any combination. The first two to four would seem to be the least objectionable and the most practicable. We urge the consideration of these suggested measures by the Park authorities and recommend that the stocking of brown trout be stopped and that at least one of the other measures be adopted.

PREVIOUS REPORTS OF NATIVE FISHES

The first published notice of the either a lowland type, now probably fish life of Yosemite National Park extinct, or was incorrectly ascribed that has come to our notice was a to the Merced River and to the Sacbrief statement by J. M. Hutchings ramento River system. (1886, p. 363), one of the pioneer Bryant in 1929 (p. 143) definitely hotel managers. He wrote: "There are but two kinds of fish in this river [the Merced], or in any of its tributaries, speckled (rainbow) trout and [Sacramento suckers]."

In the second report cited above, Evermann (1921, p. 200) stated that "the fish fauna of Yosemite National Park is not a rich one," adding that "of native species there are two suckers, three minnows, and one trout; and of these only the trout is at all common." This general statement is true, but the species list as given was hypothetical and in part incorrect. When the report was written none of the putative native species other than the rainbow trout was known by Evermann to occur within Yosemite boundaries. He stated, "there remain but two suckers and three minnows that might be found within the park." Of the five kinds mentioned, one sucker, Catostomus occidentalis, and two minnows, Mylopharodon conocephalus and Ptychocheilus grandis, have since been taken in the Park. One of the others, "Pantosteus araeopus," is currently treated as a synonym of Catostomus occidentalis. The fifth, Siphateles formosus, was either a lowland type, now probably extinct, or was incorrectly ascribed to the Merced River and to the Sacramento River system.

Bryant in 1929 (p. 143) definitely indicated that the sucker (Catostomus occidentalis) is an inhabitant of the Park and noted that the "Sacramento Pike or Squawfish" (referring to Ptychocheilus grandis) had "been taken in the Merced River close to the park line." He mentioned also: "Split tail. Native. Occasionally caught in Moss Creek near El Portal. Not known to have been taken within the park boundary." But the split-tail is Pogonichthys macrolepidotus

is at all common." This general (Ayres), an inhabitant of the lower, statement is true, but the species list main rivers in the Sacramento Valas given was hypothetical and in ley. It probably never ascends to part incorrect. When the report was such high elevations. Since Bryant written none of the putative native gave no scientific name for this species other than the rainbow species and since no specimens trout was known by Evermann to have been found to support the occur within Yosemite boundaries. record, we have assumed that no He stated, "there remain but two authoritative identification was suckers and three minnows that made. Word just received from him might be found within the park." Of confirms this assumption. The record the five kinds mentioned, one sucker, was based on the report of fisherCatostomus occidentalis, and two men who had caught some fish : minnows, Mylopharodon conocephprobably Mylopharodon conocephalus and Ptychocheilus grandis, alus or Ptychocheilus grandis that have since been taken in the Park. they called "splittail. " One of the others, "Pantosteus araeIn the fourth report on Yosemite opus," is currently treated as a fishes, Evans (1944, pp. 10-11; 1947 synonym of Catostomus occidentalis. ed., pp. 8-9) listed, in addition to trout, one sucker, Catostomus occidentalis, and two minnows, Mylopharodon conocephalus and Hesperoleucus symmetricus. All were recorded from within the Park, but the species last named was regarded as introduced.

NEW DATA ON THE NATIVE FISHES

We now add two species, both native, to the known fish fauna of Yosemite National Park, namely the Sacramento squawfish, Ptychocheilus grandis, and a sculpin, the riffle muddler, Cottus bairdii gulosus. We further show that the minnow Hesperoleucus symmetricus, previously thought to be introduced only, is really native in the Park. We thus add three species to the recognized native fish fauna of Yosemite National Park, doubling the list. The total fauna comprises the six species listed below: one trout, one sucker, three minnows and one sculpin. Of the six only the trout and the sucker are known to be of native occurrence in any of the Park waters, other than the Merced River in the Canyon, at the lowest elevations within the Park boundaries. Probably only the trout and the sucker are native to the Tuolumne River within the Park. The Tuolumne leaves the Park at a somewhat higher elevation (about 3,150 feet) than does the Merced (about 2,200 feet). These are the only rivers whose headwaters drain Yosemite National Park as at present delimited.

COMMON RAINBOW TROUT

Salmo gairdnerii irideus Gibbons

Despite all the attention that has been given the rainbow trout (including the steelhead), by ichthyologists, fishery biologists and fish-culturists, not to mention myriads of anglers, much doubt and confusion persists regarding the systematic status and scientific nomenclature of its several subspecies. There is rather general agreement only on the species name, Salmo gairdnerii (Richardson). Our tentative opinion is that the Yosemite trout of this species should be referred to S. g. irideus, which name we use for the wide-spread, generally nonmigratory, moderately coarse-scaled, relatively deep-bodied, big-headed and big-finned types. The Yosemite form has been referred to "Salmo shasta," the Shasta rainbow trout of fish-culturists, but a recent examination at Stanford University of the type specimens of Salmo gairdnerii shasta Jordan, by Hubbs and Follett, failed to disclose any valid reason for ever the subspecific recognition of shasta. It is possible that the Yosemite waters were originally populated by a slightly differentiated race of rainbow trout, but, as noted earlier (p. 132), it will probably never be possible to determine what were the characteristics of the indigenous stock or stocks. Here as elsewhere the local forms have been much contaminated and confused by the almost indiscriminate mixing indulged in by fish-culturists. Such interference with the natural order especially to be decried in the National Parks, which are supposed to be consecrated to the strict preservation of nature and of all native life within the park boundaries.

Rainbow trout were presumably native in Yosemite Park in most of the waters at moderate elevations

in both the Merced and Tuolumne species have been stocked in many river systems. The species is treated of the higher waters. They have in the four reports on Yosemite fishes spread from points of stocking upcited earlier, and in several angling stream as far as they could go. books, notably that of McDermand Downstream they may not have (1941). Lee-mee, one of the surviving been stopped even by the high falls. Indians of the Yosemite region, who Trout have been caught between has interpreted the life of the local the successive leaps of Yosemite aborigines for the Park Service, Falls and there are no records of states that trout occurred in Yosemite stocking that part of Yosemite Creek. Valley prior to the occupation of the Experiments by the senior author valley by white men, but that the Inshowed that small fish may be dians held them in lesser esteem dropped until they attain the maxthan the suckers. Obviously this imum velocity of fall, without harm view was not shared by the early if they land in water or even on hard white settlers, for Hutchings (1886, wet surfaces. p. 363) wrote that the "trout, you will find, are a delicious table fish; but no one except Indians, will think of eating suckers."

There is no reason to believe that rainbow trout or any other kind of fish ever occurred in any of the Park waters above the free-leaping waterfalls of Yosemite and Little Yosemite valleys. This view is verified by a letter written to Mr. Chester Verdeeg on July 12, 1924, by Colonel H. C. Benson, one of the early Park Superintendents. Colonel Benson stated: "When we went into the Yosemite Park there were no fish in the Park except those which were enabled to come directly up the Merced River to the Yosemite Valley and up the south fork of the Merced to within a mile or two east of Wawona and up the Tuolumne to the falls of the Hetch Hetchy except the fish that were found in Lake Eleanor and its immediate tributaries which fish had been brought in by old man Kibbe in 1877. He had put fish in Lake Eleanor and Lake Vernon but they were unable to get back into the country behind the falls of Lake Eleanor."

Since the early years of Park history rainbow trout and other exotic species have been stocked in many of the higher waters. They have spread from points of stocking up stream as far as they could go. Downstream they may not have been stopped even by the high falls. Trout have been caught between the successive leaps of Yosemite Falls and there are no records of stocking that part of Yosemite Creek. Experiments by the senior author showed that small fish may be dropped until they attain the maximum velocity of fall, without harm if they land in water or even on hard wet surfaces.

Rainbows are caught more commonly in the Merced Canyon than in Yosemite Valley. They were seen in marked abundance in pools below the power dam. On the morning of July 31, 1948, 28 adults were counted in a single pool and on the upper part of the riffle below. There is some natural reproduction of rainbows.

The differential abundance of the rainbow and brown trout of Merced River in the Canyon and in the Valley apparently reflects the recent stocking practice as well as natural habitat selection. Alan C. Taft, Chief of the Bureau of Fish Conservation of the State division of Fish and Game, which operates the fish hatchery in the Park, writes under date of October 19, 1948, that: "During the last few years we have planted the Merced River in the floor of Yosemite Valley with approximately 100,000 brown trout fingerlings each year. About the same number of rainbow have been planted but they have been largely concentrated in the swifter water between the power house and El Portal. Only the larger of our rainbow fingerlings have been planted in the floor of the Valley."

SACRAMENTO SUCKER

Catostomus occidentalis Ayres This species, the common sucker Tenaya Lake. Because of its high of the Central Valley, probably ocelevation, it is extremely improbable curs throughout the Merced and that such species are native to this Tuolumne river systems from low lake. elevations in the San Joaquin Valley Adult and half-grown suckers are to moderate elevations in Yosemite more or less solitary inhabitants of National Park. Hutchings (1886, p. the deeper, quieter pools of the Mer363), wrote of its occurrence, habits ced River. They may be seen from and utilization by the Indians in Yoearly morning until night, leisurely semite Valley. As noted above, one mouthing their way over the rock of the surviving Indians of the Valsurfaces in search of food. Using ley states that his people preferred their very fleshy papillose lips, they suckers to trout. Rutter (1908, p. 124) work like a vacuum cleaner. reported it from the Merced at Benton Mill and Livingston, from the Tuolumne at Baker Ford and from the South Fork of the Tuolumne near the mouth. It was found to be common in the Merced at Indian Flats (1,550 feet elevation) by Taft, Shapovalov, Needham and Sumner in July, 1933, and by Hubbs and Miller on July 24, 1938. Evermann (1921, p. 200) indicated that it might be found within Yosemite Park. Bryant (1929, p. 143) reported it as native in the larger streams, adding that it had supposedly been introduced into Tenaya Lake. Evans (1944, p. 10; 1947 ed., p. 8) wrote that it is common in the Merced and Tuolumne rivers at the lower elevations within the Park, but that it is seldom at home above the lower valley levels. In the summer of 1948 we found the species common in the quieter pools and margins of the Merced River from the west boundary (about 2,200 feet) through the Canyon and Valley at least to Mirror Lake (about 4,100 feet). None were seen by us in Tenaya Lake (8,141 feet), but our observations there were brief and we heard several reports of the occurrence of suckers and also of "chubs." Leo Shapovalov tells us that large suckers were found by the 1933 survey to be common in

The very young, in contrast, swim in loose to dense schools at various water levels, near the quiet margins and in small side channels. On July 31, 1948, such young-of-the-year abounded at the margins of the Merced River near the west boundary of the Park and at various points between there and the Valley. They were still very small and extremely slender (such fry can be recognized as suckers by their slenderness and by the extension of the intestine to near the caudal fin). A sample of 8 specimens dip-netted from several of the small schools ranged in standard length from 12 to 21 mm. and averaged 15.0 mm. (slightly more than one-half inch). Until disturbed, most of the fry swam near the surface, but the largest ones were beginning to live on the bottom, forsaking their early plankton-feeding habits.

Growth of suckers in the Merced River must be very slow, for 5-18 yearlings seined on July 31 (50 at one-half mile below Cascade Creek and 4 in the Valley) ranged in standard length from 33 to 64 mm., with an average of only 47.3 mm. (less than 2 inches). Large numbers of yearlings of this size range were observed in the quieter side channels

nels and on quiet sandy shallows. Like the adults, they were feeding on the bottom. The first winter annulus is close to the center of the scales and is indistinct. One two-year-old sucker in the July 31 collection, 107 mm. (slightly over 4 inches) in standard length, has a definite winter annulus near the margin of each scale.

The very slow growth of suckers in Merced River is attributable to the purity of the snow-fed water and to the scouring of the bottom by high water in the spring. By the end of July (when our collection was made) young-of-the-year suckers in a Michigan lake are as large as the yearlings in Merced River (Hubbs and Creaser, 1924). Growth is also much less rapid than in a lake in northern Wisconsin (Spoor, 1938), winter annulus near the margin of but more in accord with that reeach scale. ported by Stewart (1926) for certain The very slow growth of suckers streams in New York. The eastern in Merced River is attributable to suckers are referred to a different the purity of the snow-fed water and though very similar species, Catostoto the scouring of the bottom by mus c. commersonnii.

SACRAMENTO SQUAWFISH

Ptychocheilus grandis (Ayres) Published reports have indicated Anglers have reported for several the occurrence of this species in the years the capture of "pike" a cornMerced River, but only at elevamon misnomer for this very large tions lower than the western boundand voracious minnow—about El ary of Yosemite National Park (about Portal and in pools in the Merced 2,200 feet). It is wide-spread in the Canyon above the Park boundary. Central Valley of California (EverOn July 31, 1948, we verified these mann and Clark, 1931, pp. 52-53). claims by finding right at the boundRutter (1908, p. 133) listed it from the ary a half-grown specimen 230 mm. Merced at Livingston and Benton in standard length; obviously it had Mill. Evermann (1921, p. 200) wrote been caught in the river and had that it might occur within the Park been thrown out by a disappointed and Bryant (1929, p. 141) indicated trout angler. Later we learned that that it had been taken in the Merced a specimen had been taken in the close to the Park line. Park by the fish survey of 1933, conSacramento squawfish. h, Ranger Naturalist Martin R. Brittan from a 6 1'.-inch specimen from Merced River.

ducted by Taft, Shapovalov, Needham and Sumner. It was caught on August 18 in the Merced River 1.5 miles above El Portal and 0.2 mile within the Park boundary. No evidence was obtained to indicate that this species occurs above the power dam in the Merced Canyon and it must be rare between the dam and the boundary.

The fact that the specimen taken in 1933 was a yearling suggests that the species spawns within the Park, for the river in the Canyon is apparently too swift to be ascended by small minnows. It reproduces freely in the Merced River at Indian Flats, at an elevation of about 1,550 feet. Numerous young to half-grown specimens were taken there during the 1933 survey and yearlings were seined at the same place by Hubbs and Miller on July 24, 1938.

This large-mouthed minnow reaches a length of over three feet and is reputed to be very destructive to trout and salmon. Its predatory habits, however, should not be taken as an excuse for its destruction within the Park. Since it is of such rare though natural occurrence, it should be protected by the Park regulations.

HARDHEAD

Mylopharodon conocephalus (Baird and Girard) The inclusion of this large minnow in the Yosemite National Park list rests on the statement by Evermann (1921, p. 200) that it might occur and on the definite record by Evans (1944, p. 10; 1947 ed., p. 8), of a specimen collected on July 26, 1934, in the Merced River one-half mile below Arch Rock Entrance Station, at an elevation of about 2,800 feet. It was caught by Mrs. F. M. Watson and was received and accessioned by A. E. Borell. The identification was confirmed on July 31, 1948, by a re-examination of the specimen in the Yosemite Museum (No. 139).

This species is somewhat smaller than the squawfish, seldom reaching the length of two feet. It has a smaller mouth and a less slender head. It differs sharply in having the upper lip nonprotractile (bound to the forehead by a bridge of skin, the frenum) and in having a much shorter bony pharyngeal arch (in the throat), with molar rather than slender, hooked teeth. These differences in structure indicate that the hardhead is much less predacious than the squawfish. (Follett, 1928.)

The hardhead is probably uncommon within the Park and is almost certainly confined there to the lower elevations of the Merced Canyon. feet. It was caught by Mrs. F. M. The few that ascend the stream beWatson and was received and acyond the Park boundary (at about cessioned by A. E. Borell. The identi2,200 feet) are perhaps strays from fication was confirmed on July 31, Indian Flats (about 1,550 feet), where 1948, by a re-examination of the many young and yearling specispecimen in the Yosemite Museum mens and some older ones were (No. 139). taken during the survey of JulyThis species is somewhat smaller August, 1933. At the same place than the squawfish, seldom reaching Hubbs and Miller took yearlings on the length of two feet. It has a smallJuly 24, 1938. Rutter (1908, p. 129 got specimens farther down the Merer mouth and a less slender head. It ced River, at Livingston and Benton differs sharply in having the upper mill. The species is widely spread lip nonprotractile (bound to the forethrough the Central Valley (Everhead by a bridge of skin, the frenum) mann and Clark, 1931, p. 52), parand in having a much shorter bony ticularly in the foothill region.

Chub-roach, Hesperoleucus symmetricus, drawn by Ranger Naturalist Martin R. Brittan from a 3½ inch specimen collected by Rutter in Merced River at Livingston.

SIERRA CHUB-ROACH

Hesperoleucus symmetricus (Baird and Girard), subspecies This somewhat speckled, finger-length minnow was reported from Yosemite National Park by Evans (1944, pp. 10-11; 1947 ed., pp. 8-9). In the Park it has been known only in Hetch Hetchy Reservoir and it is said to have first appeared there in 1930. Apparently on circumstantial evidence it has been assumed that it was introduced by the dumping of live bait. That may well be true, but it is also wholly possible that it existed in small numbers in the Tuolumne River in Hetch Hetchy Valley (elevation 3,680 feet), prior to the impoundment, and that it did not build up a conspicuous population in the lake until 1930. The possibility that the species naturally ascended the Tuolumne to populate Hetch Hetchy Valley finds support in our discovery of its occurrence and breeding in the Merced River at the western boundary of Yosemite National Park, at an elevation of about 2,200 feet.

The discovery of this minnow in the Merced River at the park boundary came about in an unexpected way. It was not recognized during the examination on the river on July 31, 1948. On sorting the collection of fry dip-netted on that day in the quiet margins of the river, it was noticed that the six smallest specimens, each 9 mm. (3/8 inch) in standard length, were minnows, not suckers. The expectation that these larvae might represent Hesperoleucus symmetricus was verified by comparing the specimens with Fry's (1936) excellent figures and descriptions of the developmental stages of the Baystream chub-roach, H. s. venustus Snyder. In all details of form and proportions, position and development of fins, and pigmentation, our 9 mm. postlarvae are just intermediate between the 8.5 and 9.5 mm. stages figured by Fry. There seems to be no doubt about the specific identification.

In all probability Hesperoleucus symmetricus is native in the Merced River within the Park, though it is undoubtedly scarce at elevations above 2,000 feet. It is probably very inconspicuous there, for in the swift water it would tend to seek retreat under boulders. Those that do occur so far upstream (and at least occasionally breed there) presumably

stem from a rather large population in the river at Indian Flats (about 1,550 feet). Many young to adult specimens were taken there during the 1933 survey and yearlings plus two adults were seined at the same place by Hubbs and Miller on July 24, 1938.

The species Hesperoleucus symmetricus is of wide occurrence through the Central Valley of California and in the contiguous coastal streams (Snyder, 1913, pp. 63-70). In the Merced and Tuolumne river systems it is probably common at many places below the localities already mentioned. Rutter (1908, p. 139) had it from the Merced at Benton Mill and Livingston, from the North Fork of the Merced at Bower Cave, from the Tuolumne at Baker Ford, and from the South Fork of the Tuolumne near its mouth.

The subspecies that occurs in and near Yosemite National Park appears to be one of the several local forms that are still unnamed. Snyder renamed a number (giving them full species rank), but, overimpressed with the importance of geographical segregation in separate stream systems, he did not distinguish sub-species within the Sacramento-San specimens were taken there during Joaquin system. Rutter (1908, pp. 137-139) had already pointed out the 1933 survey and yearlings plus 137-139) had already pointed out two adults were seined at the same marked local variations, even within place by Hubbs and Miller on July the Merced River system. Much of 24, 1938. the differentiation appears to be The species Hesperoleucus symecotypic. The typical subspecies, H. s. symmetricus, inhabiting the metricus is of wide occurrence main rivers with a strong and conthrough the Central Valley of Cali stant current, has a very slender fornia and in the contiguous coastal caudal peduncle and long, expanstreams (Snyder, 1913, pp. 63-70). In sive and falcate fins, the dorsal usuthe Merced and Tuolumne river sysally with 10 and the anal ordinarily tems it is probably common at many with 9 rays. The unnamed foothill places below the localities already form, inhabiting the quieter spots of mentioned. Rutter (1908, p. 139) had the smaller pool-and-riffle streams, it from the Merced at Benton Mill has a chunkier build with deeper and Livingston, from the North Fork caudal peduncle and smaller, more of the Merced at Bower Cave, from rounded fins, the dorsal usually with the Tuolumne at Baker Ford, and 9 and the anal ordinarily with 8 from the South Fork of the Tuolumne rays. These contrasting but inter near its mouth. grading types are paralleled by The subspecies that occurs in and near Yosemite National Park appears to be one of the several local forms that are still unnamed. Snyder renamed a number (giving them full species rank), but, overimpressed with the importance of geographical segregation in separate stream systems, he did not distinguish subspecies within the Sacramento-San Joaquin system. Rutter (1908, pp. 137-139) had already pointed out marked local variations, even within the Merced River system. Much of the differentiation appears to be ecotypic. The typical subspecies, H. s. symmetricus, inhabiting the main rivers with a strong and constant current, has a very slender caudal peduncle and long, expansive and falcate fins, the dorsal usually with 10 and the anal ordinarily with 9 rays. The unnamed foothill form, inhabiting the quieter spots of the smaller pool-and-riffle streams, has a chunkier build with deeper caudal peduncle and smaller, more rounded fins, the dorsal usually with 9 and the anal ordinarily with 8 rays. These contrasting but intergrading types are paralleled by ecotypic subspecies in many species of western fresh-water fishes (Hubbs, 1940a, pp. 199-200; 1941, pp. 186-187). The character gradients are repeated again and again in close correlation with the biological gradients. Riffle muddler, Cottus bairdii gulosus, drawn by Ranger Naturalist Martin R. Brittan from a specimen from Merced River in Yosemite National Park.

RIFFLE MUDDLER

Cottus bairdii gulosus (Girard) This fresh-water sculpin is another specimens were found among the addition to the known fish fauna of many fishes collected during the Yosemite National Park. It was re1933 survey, either at Indian Flats ported by Rutter (1908, p. 146) south- (about 1,550 feet) or in the Park. ward only to Stanislaus River, the None was obtained at Indian Flats first main stream north of the Tuoby Hubbs and Miller on July 24, lumne. Dill (1946, pp. 54-55) reported 1938,.though special effort was made a species of Cottus from the San Joato collect sculpins by methods that quin River, the first main mountain are usually productive overturning stream of the Merced, but a speciboulders and stones and kicking in men from Millerton Lake, submitted vegetation, in such a way that the by him, proves to be Cottus asper fish are swept into a small seine set Richardson. We find no published below and partly around the operarecords of any Cottus for either the tion. Such methods employed on Tuolumne or the Merced system. The July 31, 1948, yielded only the one occurrence of the species in Merced specimen at the park boundary and River is substantiated by four colnone in the river below Cascade lections, each of a single specimen Creek or on the Valley floor. and all from within the Park. The According to L. C. Nixon, foreman first three specimens are in the Yoof the local State fish hatchery, the semite Museum, the fourth, in the "bullheads" that occur in Merced University of Michigan Museum of River near the western Park boundZoology. The data follow: ary reach a length of six inches. One adult from Merced River beThe muddlers or fresh-water low the dam and above Arch Rock sculpins (miller's thumb and bullEntrance Station, at an elevation of head are other names) are small about 3,700 feet; caught by Mrs. scaleless (sometimes prickly) fishes Lucy Cleveland on July 14, 1934, and with expanded pectoral fins, the received by A. E. Borell. pelvic (ventral) fin below the pecOne adult from Merced River near toral base, two dorsal fins (the first the Incline; caught by a woman with low, threadlike spines), a broad angler on July 10, 1938. and rather flat head, a small eye on One adult from Merced River at the upper part of the head, one or Steamboat Bay (a large stream pool), more small preopercular spines (on at an elevation of about 3,600 feet; the side of the head), and rather caught on a worm by Erwin Brocker dark, usually mottled color. on August 22, 1938. The systematics of the American One half-grown specimen 52 mm. species of Cottus is in a state of unin standard length, from the Merced certainty. The far-western form that River at the west boundary of the has generally been named C. Park (about 2,200 feet); taken by us gulosus should apparently be in a small seine by overturning treated as a subspecies of Cottus boulders, on July 31, 1948. bairdii, for gulosus and C. b. bairdii The species must be rare in the (of eastern North America) seem to Merced River. The lower courses of belong to the same wide-spread and the river in San Joaquin Valley do variable species complex. The form not provide suitable habitats. No gulosus as currently recognized is

perhaps in itself a complex of subfeatures of the four specimens from species and it is not certain that the the Merced River. The lateral line Merced River form should be identiis complete. Palatine teeth are well fied as C. b. gulosus. Several of the developed. Prickles are confined to local forms in the Sacramento systhe axil. The dorsal fins are only tem, including the one named Cottus slightly connected. The fin rays num shasta, seem to be worthy of sub ber : dorsal spines, 9; dorsal soft specific separation. rays, 18 (in 3) or 19 (1); anal rays,

13 (1) or 14 (3); pectoral rays, 15 (1 In view of the confusion that exfins) or 16 (2 fins); pelvic rays 1, 4: ists, we give some of the salient principal caudal rays, 10 (1) or 11 (2).

OTHER SPECIES OF POSSIBLE NATIVE OCCURRENCE

It seems doubtful to us that there Ptychocheilus grandis, Mylopharowill be any further increases in the don conocephalus and Hesperoleulist of fishes known to be native in cus symmetricus. We are greatly the waters of Yosemite National indebted to Mr. Shapovalov, now Park. Even a considerable extension with the California State division of of the boundaries (or a considerable Fish and Game, for permission to trip beyond the present limits) would examine and to list fishes taken probably add none. The Mono Lake during the 1933 survey. drainage basin across the Sierra rim Since none of the other, more low to the eastward seems to be devoid land species of the Central Valley of native fish life (Hubbs and Miller, were obtained at 1,550 feet in In 1948, pp. 78-79). It is unlikely that the dian Flats, it is extremely doubtful Park area will be extended far that any of them have ever reached enough to the northeastward to in the Park boundaries, or will likely clude waters in the Walker River do so by natural dispersal. Exclu system that contain native Lahontan sive of the anadromous forms which species. An extension of the bound with even greater assurance can be ary in the mountains northward or regarded as unable to reach the southeastward or southward would Park at present, these lowland forms presumably bring in no additional may be listed as follows: species. An extension to much lower elevations to the westward would Lampreys, family Petromyzonidae: probably be required to add other European brook lamprey, Lampetra species. planeri (Bloch). There are now known from within Minnows, family Cyprinidae: the Park all species that have been blackchub, Orthodon microlepidotus obtained during extensive collecting (Ayres); splittail, Pogonichthys macin the Merced River at Indian Flats rolepidotus (Ayres); thicktail, Gila at an elevation of about 1,550 feet. crassicauda (Baird and Girard); SacCollections were made there in ramento hitch, Lavinia e. exilicauda July and August, 1933, during the Baird and Girard; Sacramento tui, fish survey conducted by Alan C. Siphateles obesus formosus (Girard). Taft, Leo Shapovalov, Paul R. Needham and Francis H. Sumner, and on Sunfishes, family Centrarchidae: July 24, 1938, by Carl L. Hubbs and Sacramento-perch, Archoplites inRobert R. Miller. Both parties col terruptus (Girard). lected only Catostomus occidentalis, Surfperches and seaperches, fam-

ily Embiotocidae: valleyperch, Hysix kinds that are known to have sterocarpus traskii Gibbons. extended their range beyond the One other minnow species listed boundary appear to be confined to by Rutter (1908, pp. 139-140) as the lower elevations of the Merced Agosia robusta but now called RhinRiver Canyon. It is possible that they ichthys osculus, occurs at various originally occurred as high as Yoelevations in the Sacramento-San semite Valley (3,900 to 4,100 feet eleJoaquin system, but oddly seems to vation), but, if so, they have probskip the Yosemite region in its disably been extirpated there by high tribution. The subspecies of this water, by the power dam that preriver system are undetermined. vents reinvasion and by the predaThe fish fauna of Yosemite Na- tion of trout, particularly brown trout tional Park is limited and restricted Among the native fishes only the by the steep gradient of the streams rainbow trout and the Sacramento and by the torrential rush of water sucker are definitely known to ocduring the rapid melting of the deep cur either in Yosemite Valley or in snowfall on the Sierra Nevada. the Tuolumne River system within Many species of the Sacramento the Park boundaries. Suckers and fauna fail to ascend either the trout are particularly adept in surMerced or the Tuolumne River mounting torrential waters. As would to the western boundary of the Park be expected, no native fish occur (at elevations of about 2,200 and above the high plunging falls of Yo3,150 feet, respectively). Four of the semite National Park.

SUMMARY AND CONCLUSIONS

The National Parks have been would be needed to improve very consecrated to the strict protection markedly the natural biotic condiof that part of the native animal and tions in the streams. It is recomplant life which lives above the mended, however, that the stocking water surface, but the Park Service of the exotic brown be discontinued. has commonly treated the aquatic Hitherto only three fish species life as a recreational asset. Hunting have been reported as native in Yois prohibited but fishing is often ensemite watersrainbow trout, Salmo couraged. Exotic terrestrial animals gairdnerii irideus; Sacramento suckare rigidly excluded but exotic fishes er, Catostomus occidentalis; and a have often been stocked. A comprolarge minnow, the hardhead, Mylomise policy has been adopted. It pharodon conocephalus. We now calls for the preservation of aquatic double the list, adding three minnows life in the Parks where conditions (the squawfish, Ptychocheilus are yet unspoiled and otherwise to grandis, and a chub-roach, Hespersome degree restricts the recrea oleucus symmetricus) and also one tional developments. The trend toward apreservationist policy for the fresh-water sculpin, the riffle mudaquatic life might well be extended dler, Cottus bairdii gulosus. Notes when and where it would be pracare included on the biology of the ticable to do so. In Yosemite Nationsix native species, including a brief al Park, however, fishing under presstudy of the slow growth of the suckent regulations will probably have er. It is unlikely that any additional relatively little further effect on the native species will be discovered in native aquatic life. Drastic measures the Park waters.

LITERATURE CITED

Bryant, H. C. 1929. Fish and fishing in YoHubbs, Carl L., and Creaser, Charles W. 1924. semite National Park. Yosemite Ranger On the growth of young suckers and the Naturalists Manual, Vol. 3, pp. 142-149. propagation of trout. Ecology, Vol. 5, No. 4, Cahalane, Victor H. 1947. Wildlife managePP. 372-378, figs. 1-2. ment in the National Park system. Yosemite Hubbs, Carl L., and Lagler, Karl F. 1949. Fishes NATURE NOTES, Vol. 26, No. 5, pp. 69-70. of Isle Royale, Lake Superior, Michigan. Pap. Dill, William A. 1946. A preliminary report on Mich. Acad. Sci., Arts, and Letters, Vol. 33, the fishery of Millerton Lake, California. for 1947, pp. 73-133, figs. 1-2, pls. 1-2. Calif. Fish and Game, Vol. 32, No. 2, pp. Hubbs, Carl L., and Miller, Robert R. 1948. 49-70, figs. 10-17. The zoological evidence: correlation between Evans, Willits A. 1944. Fishes of Yosemite fish distribution and hydrographic history National Park. Yosemite Nature Notes, Vol. in the desert basins of western United 23, No. 1, pp. 1-20, 9 figs. (reprinted 1946, States. Bull. Univ. Utah, (Biol. Ser.) Vol. 10, revised 1947 by George J. Ross, Jr.). No. 7, pp. 17-166, figs. 10-29, map 1. Evermann, Barton Warren. 1921, The fishes of Hutchings, J. M. 1886. In the Heart of the Yosemite National Park. In : Handbook of Sierras. Pacific Press Publishing House, OakYosemite National Park, edited by Ansel F. land. 496pp. Hall, G. P. Putnam's Sons, New York and Madsen, David H. 1937. Protection of native London, pp. 183-201, pls. 14-15. fishes in the National Parks. Trans. Am. Fish. Soc., Vol. 66, for 1936, pp. 395-397, Evermann, Barton Warren, and Clark, Howard McDermand, Charles. 1941. Yosemite and Walton. 1931. A distributional list of the Kings Canyon trout. G. P. Putnam's Sons, species of freshwater fishes known to occur New York xii +178 pp., 16 pls., 1 map in California. Div. Fish and Game California, (quoted from 1947 ed.). Fish Bull. No. 35, 67 pp. Rutter, Cloudsley. 1908. The fishes of the Follett, W. I. 1928. A note on the squawfish and Sacramento-San Joaquin basin, with a study one of its relatives. Calif. Fish and Game, of their distribution and variation. Bull. U. S. Vol. 14, No. 4, pp. 282-285, figs. 89-92. Bur. Fish., Vol. 27, for 1907, Doc. No. 637 Fry, Donald H., Jr. 1936. Life history of Hesperoleucus symmetricus Snyder, Calif. Fish and Snyder, John Otterbein. 1913. The fishes of the streams tributary to Monterey Bay, California. Bull. U. S. Bur. Fish., Vol. 32, for Game, Vol. 22, No. 2, pp. 65-98, figs. 25-33. Hubbs, Carl L. 1940a. Speciation of fishes. Am. Nat., Vol. 74, No. 3, pp. 198-211 (also in Biological Symposia, The Jacques Cattell Am. Nat., Vol. 74, No. 3, pp. 198-211 (also Press, Lancaster, Pa., 1941, pp. 7-20). Hubbs, Carl L. 1940b. Fishes from the Big Bend region of Texas. Trans. Texas Acad. Sci., Vol. 23, for 1938-1939, pp. 3-12. Spoor, William A. 1938. Age and growth of the sucker, Catostomus commersonnii (Lacépède), in Muskellunge Lake, Vilas County, Wisconsin. Trans. Wisc. Acad. Sci., Arts and Letters, Vol. 31, pp. 457-505, figs. 9-13, pl. I.

Hubbs, Carl L. 1941. The relation of hydrological conditions to speciation in fishes. In: A Symposium on Hydrobiology. University of Wisconsin Press, Madison, pp. 182-195.

Stewart, Norman Hamilton. 1926. Development, growth and food habits of the white sucker, Catostomus commersonnii LeSueur. Bull. U. S. Bur. Fish., Vol. 42 (Doc. No. 1007), pp. 147-184, figs. 1-55.

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