Propagation of the Creek Chub in Ponds with Artificial Raceways

Abstract

Successful spawning of the creek chub (Semotilus a. atromaculatus) was achieved in a specially designed raceway. An artificial stream, having a gravel bottom with pools and riffles, was constructed within the basin of a pond in which brood stock were introduced. Spawning activity commenced in late April and terminated in early May. A heavy mortality occurred among the brood stock when the ratio of males was equal to, or greater than that of the females. A better survival was attained by increasing the number of females. The breeding fish had a tendency to concentrate in certain zones of the spawning raceway, and as a result many redds were destroyed in the overworked areas. To offset this condition, thus increasing the efficiency of the raceway, deposited eggs were removed from the beds and successfully cultured in a hatchery by the use of Mechean jars and egg trays. The complete incubation period (fertilized egg to free-swimming fry) was about 25 days at a mean temperature of 55° F. Several rearing ponds were stocked with 8-day-old fry; others with 20-day-old fry. Though the 8-day-old fry were found to tolerate long-distance transporting, they did not survive in any appreciable numbers after introduction into rearing ponds. The stocking of ponds with 20-day-old fry was more successful, for more than 50 percent of the fry survived. Production in ponds where the fish had to rely on a natural food supply was light as compared to that achieved in a pond where artificial feeding was practiced.