BRIEF NOTE even in fast riffles" (Raney, 1940). Males conducting nest-building activities FUNCTION OF CREEK CHUB work against swift currents, however, ( ATROMACULATUS) 1 and probably expend large amounts of NEST-BUILDING. energy in this activity. If the major function of nest-building were to cover The creek chub is a small stream dwell- eggs with gravel for protection, such ing cyprinid distributed over much of the activity, during periods when no un- United States and southern Canada east covered eggs are in the nest, would ap- of the continental divide (Blair et al, pear to be a non-adaptive expenditure of 1968). During the spawning season, energy. Measurable differences should which occurs in the spring when water occur in nest-building rates of fishes temperatures warm to 12-16°C (Greeley, actively spawning versus those not 1930; Washburn, 1948), male creek chubs spawning. move onto gravel runs to build nests; Quantitative observations of nest build- each male guards his nest and spawns ing were made during April and May in with females that enter it. In small 1973 and 1974 on three small streams in streams nests often occur singly, but in . One is a tributary of Grant's larger streams male chubs nest at the Run, Jackson Township, Franklin downstream edge of large pools. Five county, and the other two are tributaries to 10 males may build nests at such loca- of Clear Creek (located in Barnebey Cen- tions (Ross, 1975). Although the - ter, a natural area maintained by the ing act is always conducted by a pair, School of Natural Resources of Ohio numerous females may spawn with a State University), Madison Township, single male during the two or more days Fairfield County. Data were collected that he is actively nesting. when spawning activity was initiated The male forms a nest depression by by using 7 x 35 mm binoculars from the carrying sand and gravel from the nest in stream banks. I observed 33 nesting his mouth. Once a depression is formed, male creek chubs and recorded for each the male removes gravel only from the fish the number of movements made per downstream edge of the depression. minute to the upstream edge of the nest This material is deposited on the up- depression with a mouthful of gravel. stream edge of the depression in the area Observations were recorded and averaged where spawning occurs. Thus, eggs that for each male during a 30 or 60 minute are released in the nest are subsequently observation period. Movements of males covered with a layer of gravel which is pushing gravel from place to place in a moved by the male. Nest-building activ- small area of the nest were not included ity slowly moves the depression down- in the data because this behavior oc- stream and forms a gravel ridge contain- curred inconsistently and was not easily ing eggs in the area through which the quantified. Males were separated into nest has been moved. Reighard (1910) two groups: those that spawned at least showed illustrations of a creek chub nest once while being observed or had fre- and related the adaptiveness of nest- quent contact with females in the nest building to egg protection. He indicated (Group 1), and those that neither that nest-building is a continuous process, spawned nor had contact with females independent of spawning activity. (Group 2). Male creek chubs appear to expend The mean nest-building rate of Group little energy maintaining a position in the 1 males was greater than that of Group 2 nest depression, since the flow of water males (table 1). An analysis of variance over a nest pit, "is such that eddys are indicated the means of the two groups formed, bringing water in the bottom of were significantly different (P<.01). In the pit to a relatively quiet condition one study, 2 male chubs were each ob- Manuscript received March 3, 1976 and in re- served for 2 consecutive 30-minute peri- vised form, as a note, June 29, 1976 (#76-23). ods, the first during which no spawning 36 No. 1 CREEK CHUB NEST BUILDING 37

TABLE 1 other than spawning were observed The nest-building movements /minute of around the nests of Group 1 versus male creek chubs. Group 2 males. The nest-building activity of male Average creek chubs that spawned or had contact Group No. No. of Movements/ with females while being observed was Obs. Fishes Min. greater than that of males that did not. Nest-building of non-spawning males was Males spawning sporadic. An increase in nest-building or contacting activity normally follows spawning. females 145 13 4.9* Miller (1904) proposed that nest-building Males not spawning 20 2.0 of the river chub, micropogon, 165 could function in attraction of females. •Statistically different (P<.01; F is 17.0) Although sporadic nest-building activity from non-spawning males. of non-spawning creek chubs could func- tion in this manner, the major time and occurred, and the second during which energy expenditures relegated to nest- each male spawned at least once. The building by male creek chubs serve to nest-building rates of both males in- cover freshly fertilized eggs with gravel, creased when spawning occurred (table 2). apparently to give them protection. Thirty-one percent (51 of 165) of the MICHAEL R. ROSS,* Department of 1-minute nest-building counts for Group Zoology, The Ohio Slate University, Co- 2 males were scored 0, whereas 3% (4 of lumbus. TABLE 2 * Present Address: Department of For- Nest-building movements /minute of 2 males estry and Wildlife Management, Uni- before and after spawning. versity of Massachusetts, Amherst, Mass. 01002. No. of Movements/min Acknowledgment. I wish to thank Ted Fish Counts =*= S.D. Cavender for the aid he provided during this investigation. Before 10 0.0 LITERATURE CITED Male A Blair, W. F., A. P. Blair, P. Brodkorb, F. After 12 2.8=^1.7 Cagle and G. A. Moore. 1968. Vertebrates of the United States. McGraw Hill Book Before 11 3.4±0.9 Co., N. Y. 616 p. MaleB Greeley, J. R. 1930. A contribution to the After 11 5 1=1=1.0 biology of the horned dace, Semotilus atro- maculatus (Mitchell). Unpubl. Ph.D. The- sis, Cornell Univ. Ithaca. Miller, R. J. 1964. Behavior and ecology of 145) of the 1-minute counts for Group 1 some North American cyprinid fishes. males were scored 0. Counts per minute Amer. Midi. Nat. 72: 313-357. of 0 were recorded at least once for 14 Raney, E. 1940. The breeding behavior of the , cornutus (Mit- out of 20 Group 2 males, and for 2 out of chell). Zoologica 26: 1-14. 13 Group 1 males. In the 4 counts of 0 Reighard, J. 1910. Methods of studying the recorded for Group 1 males, numerous habits of fishes, with an account of the breed- aggressive encounters with other nest- ing habits of the horned dace. Bull. U.S. intruding fishes prevented the males from Bur. Fish. (Wash., D.C.) 28: 1111-1136. Ross, Michael R. 1975. The breeding be- moving gravel to the upstream edge of havior and hybridization potential of the the nest uninterrupted. Many of the northern Creek Chub Semotilus atromaculatus 51 one minute scores of 0 for Group 2 atromaculatus (Mitchell). Unpubl. Ph.D. males, however, were not recorded during Thesis, Ohio State Univ., Columbus. Washburn, G. N. 1948. Progogation of the periods of intensive aggressive activity. creek chub in pools with artificial raceways. No consistent differences in activities Trans. Amer. Fish. Soc. 75: 336-350.