Royal D. Suttkus

Fecundity of the Spotted Seatrout, Cynoscion nebulosus (Cuvier), from Lake Borgne Area, Louisiana

Abstract Fecundity of the spotted seatrout, Cynoscion nebulosus, from Louisiana waters was estimated by the gravimetric method. By actual counts this method involved an error of 6.93 percent. Fecundity increased with length and age. The ovary is heavier than the testis for individuals (greater than 280 millimeters in total length) of comparable age and size. Mean volume, mean diameter of ova, mean number of eggs per gram weight of ovary, and mean testis weight indicate a spawning peak in July. Members of age-groups II, III, and IV contribute 91.9 percent of the supply of eggs. Members of age-group I contribute little to the supply of eggs.

Reclamation of the Pearl River: A Perspective of Unpolluted versus Polluted Waters

Abstract Historically the Pearl River received large amounts of municipal sewage and industrial wastes. The river was ultimately reclaimed by installation of primary and secondary treatment facilities for both effluents. No violations of state or federal water quality criteria were observed in the 10-year period subsequent to installation of treatment facilities. Positive results of pollution abatement and river reclamation were: (1) an increase in clean water species of fishes and invertebrates, (2) a decrease in pollution tolerant species such as the annelid Tubifex, (3) reestablishment of unionid mussel populations in the reclaimed river segment, and (4) increased growth rates for some species of fishes.

THE STATUS OF THE ROCK BASS POPULATION IN BLUE SPRING, NEW MEXICO, WITH COMMENTS ON THE INTRODUCTION OF ROCK BASS IN THE WESTERN UNITED STATES'

The previously undetermined status of the rock bass in Blue Spring, a tributary to the Pecos River drainage in southeastern New Mexico, has created some confusion. One view holds that the population may represent an undescribed form or a native relict that should be protected. Examination of 34 specimens from Blue Spring and detailed comparison with many specimens from eastern popula- tions has led us to conclude that the Blue Spring population represents an introduc- tion of the northern rock bass, Ambloplites rupestris. Information from the New Mexico Department of Game and Fish and records of the U.S. Commission of Fish and Fisheries indicate that Blue Spring rock bass were established from brood stock introduced from east of the Mississippi River between 1891 and 1903. Records for established populations of rock bass in other states west of its native range are briefly mentioned. The status of the rock bass in Blue Spring, a tributary to the Pecos River drainage in southeastern New Mexico, has remained undeter- mined until now. Hubbs and Echelle (1973) reported on the rock bass from Blue Spring. According to these authors there was no evi- dence of introduction and the population appeared to be superficially distinctive. At one time the Blue Spring rock bass was considered for endangered species status. We examined the rock bass material collected by Hubbs and Echelle