State of California The Resources Agency DEPARTMENT OF FISH AND GAME STATUS AND PROPOSED MANAGEMENT OF THE ROUGH SCULPIN, COTTUS ASPERRIMUS RUTTER, IN CALIFORNIA by Robert A. Daniels, Ph.D. New York State Museum, Albany and Louis A. Courtois, Ph.D. Inland Fisheries, Sacramento Inland Fisheries Endangered Species Program Special Publication 82-1 February 1982 LDA Endangered Species Program Special Publications are nonrefereed reports generally of two types: they may contain information of sufficient importance to be preserved for future reference but which may not be currently appropriate for journal publications; or they may be reports which contain information of current significance that warrants early dissemination to biologists, managers, and administrators but which may later be submitted for formal scientific publica- tion. These reports can be cited in publications, but their manuscript status should be recognized. Subject matter reflects the broad array of research and management conducted in California on nongame species of reptiles, amphibians, and nonmarine fishes and invertebrates, with primary emphasis on endangered, threatened, and rare taxa. Inquiries concerning any particular report should be directed to the Inland Fisheries Branch, 1416 Ninth Street, Sacramento, California 95814. STATUS AND PROPOSED MANAGEMENT OF THE ROUGH SCIAPIN, COTTUS ASFERRIMUS RUTTER, IN CALIFORNIAL/ by / Robert A. Daniels, Ph.D.- and / Louis A. Courtois, ABSTRACT The rough sculpin, Cottus asperrimus, is a small, demersal fish inhabiting the large tributaries flowing into the middle portion of the Pit River in northeastern California. It is probably a relict from a large Pleistocene lake which once covered the area and is adapted to an environmentally stable habitat. This fish is biologically rare due to its extremely small range and was so designated by the California Fish and Game Commission in 1973. Although it is not currently endangered, it is potentially threatened by habitat degradation in the form of increased shoreline development, changes in land use, and introduction of exotic organisms. Monitoring of the fish and its habitat will be necessary to determine any unnatural decline of this ecologically interesting sculpin. 1/ In1and Fisheries Endangered Species Program Special Publica- tion 82-1. This report was prepared as part of an Endangered Species Act grant-in-aid project, "California E-F-4, Endangered, Threatened, and Rare Fish." Direct reprint requests to junior author. 2/ New York State Museum, Biological Survey, Cultural Education Center, Room 3122, Albany, New York 12230. 3/ Fishery Biologist, Endangered Species Program, Inland Fisheries Branch, 1701 Nimbus Road, Rancho Cordova, California 95670. Current address: Anadromous Fisheries Branch, 1701 Nimbus Road, Rancho Cordova, California 95670. -3- INTRODUCTION The rough sculpin, Cottus asperrimus, is the smallest member of the family Cottidae in California. It is unmistakenly identified by its relatively narrow body shape and extremely rough skin. The specific name, asperrimus, translated from Latin means "most rough". Cottus asperrimus occupies the middle reaches of the Pit River system of north- eastern California. Rutter (1908) sampled this area of the upper Sacramento River drainage and collected five type specimens from the Fall River near Dana (Figure 1) in the latter part of the nineteenth century. In 1973, the California Fish and Game Commission declared the rough sculpin rare, a status merited by its extremely small range and by its relatively infrequent occurrence in samples. In 1974, the California Department of Fish and Game conducted a general stream survey of the Pit River system to determine the range and relative abundance of the rough sculpin (Daniels and Moyle 1978). Management of the rough sculpin, as with any organism, requires a defined purpose and goal. The purposes of this paper are to summarize the available information on the rough sculpin, and outline activities to be carried out by the California Department of Fish and Game in cooperation with local landowners. The goal of these activities is to ensure continued protection of the rough sculpin population and enhancement of its existing habitat. To properly achieve this goal, an understanding of the life history and distribution of C. asperrimus is necessary. Once this information is known, a cooperative effort, including the private sector and all concerned governmental agencies, is needed to formulate and implement a protection plan. Here we compile what is currently known about the biology of the rough sculpin and offer recommenda- tions which, if implemented, will serve to protect not only the species but also the habitat in which it lives. NOMENCLATURE Cottus asperrima, Rutter, 1908:144-5 Cottus gulosus, Snyder, 1917:82 Cottus asperrimus, Hubbs and Schultz, 1932:5 Cottus asperrimus, Hubbs and Miller, 1948:69 Cottus asperrimus, Bailey and Dimick, 1949:16 Cottus asperrimus, Shapovalov and Dill, 1950:387 Cottus asperrimus, Robins and Miller, 1957:223 Cottus asperrimus, Shapovalov, Dill, and Cordone, 1959:173 Cottus asperrimus, Moyle, 1976:365 Cottus asperrimus, Daniels and Moyle, 1978:673-679 Cottus asperrimus, Shapovalov, Cordone, and Dill, 1981 DESCRIPTION The rough sculpin was first described by Cloudsley Rutter in a preliminary report to the Bureau of Fisheries which was not completed at the time of his death in 1903. The report was finally published in 1908 with only minor revision. Rutter based the description on five specimens, the holotype (No. 58500, United States National Museum) and four paratypes. The type STAREDAY Goose Lake MT. SHAST Alt uras a Canby South Fork A Pit River Adin McCLOUD L RIVER Big Lake ') ..FALL R. ' Bieber "N Fall ttvilte PIT River RIVER Mills Burney Cassel Burney IC km Cr. SHASTA L AKE HAT CR. SACRAMENTO RIVER 122°00' LASSEN PK. 120°30' 1. Pit River system, northeastern California. Stippled area shows contiguous range of rough sculpin, Co,ttus asperrimus. -5- was the Fall River at Dana, The following description is based on that of Rutter (1908), Robins and Miller (1957), Moyle (1976), and personal observa- tions of the senior author. The rough sculpin possesses a slender but not particularly compressed body. The dorsal and ventral surfaces are finely mottled, varying in color from gray to light brown. The mottling forms four or five lateral blotches. The venter tends to be white, although Robins and Miller (1957) state that the venter shows "profuse chromatophores". The dorsal and pectoral fins are barred; the anal fin may possess some chromatophores on the rays; and the pelvic fins are white. Moyle (1976) describes the meristic characteristics: Rough sculpin...consistently have 1 spine and 3 rays in the pelvic fins (three elements). There are 5 to 7 spines in the first dorsal fin, 17 to 19 rays in the second dorsal, 13 to 17 anal-fin rays, 14 to 16 rays in each pectoral fin (many of them branched), and 19 to 29 lateral-line pores. Rutter (1908) describes the mensural characteristics: Head 3.2 to 3.33 in length; depth 5.5; eye 3.5 to 4 in head; snout a little longer than eye; width of caudal peduncle 1.25 to 1.33 in eye, its depth slightly greater than eye; maxillary 2.5 in head, extending to vertical through anterior edge of pupil; profile flat or concave back of eye; interorbital space 0.5 of eye; spinous dorsal low, its outline not so strongly arched, .spines very weak, longest about equal to eye; longest soft ray of dorsal about 2 in head; origin of soft dorsal at or behind middle of body; caudal convex, 1.33 to 1.43 in head; ventrals 1.6 in head, the rays graduated, the outer 0.66 length of inner; distance from snout to vent 0.54 to 0.56 of body. There is no discernible sexual dimorphism in either color, meristics, or morphometrics. It is morphologically simlar to the slender sculpin, C. tenuis, of the Klamath River drainage and this relationship may indicate a previous connection between these two drainages (Hubbs and Miller 1948). Rough sculpin can be distinguished from the marbled (C. kZamathensis), Pit (C. pitensis), and riffle (C. gulosus) sculpins, other cottids present in the Pit River system, by its general body shape, color, size,and amount of axillary prickles on the body. Table 1 compares some characteristics between C. asperrimus and C. tenuis, the sculpin with which it is most morphologically similar, and between the other sculpins with which it is most commonly collected, C. klamathensis and C. pitensis. TAXONOMY The taxonomic status of C. asperrimus is remarkably simple. The species has been regarded as valid since its original description, except for a brief period when Snyder (1917) synonymized C. asperrimus with C. gulosus. However, this change was not widely accepted (Hubbs and Schultz 1932; Hubbs and Miller 1948), and the two species were removed from synonymy by Bailey and Dimick (1949). Cottus asperrimus is the most similar in TABLE 1. Comparison of Meristic Characteristics and Color Among Four Species of Sculpins from Northeastern Californial/. Character C. asperrimus C. tenuis C. kZamathensis C. pitensis Anal rays 13-17 13-17 13-15 13-15 Dorsal rays 17-19 17-19 18-20 17-18 Dorsal spines 5-7 5-6 5-7 8-9 Dorsal interspace present present absent present Pectoral rays 14-16 13-16 14-16 13-15 Pelvic elements usually 3 usually 3 usually 4 usually 4 Caudal rays (branched) usually 7 usually 7 usually 9 usually 9 Preopercular spines 1+ 3 1-2 2-3 Lateral-line pores 19-29 23-32 14-29 31-39 Lateral line continues to continues to continues to continues to last dorsal ray caudal peduncle caudal peduncle caudal peduncle Axillary prickles extensive extensive to usually absent patch mesial to moderate pectoral fin General color gray to light gray to brown yellow to olive yellow to green olive or brown brown Color of venter white with some silvery to green brown light yellow to scattered chroma- brassy brown tophores 1/ - Information compiled from Rutter (1908), Robins and Miller (1957), and Moyle (1976).