Ecology, Foods and Feeding of the Longnose Shiner, Notropis longirostris (Hay), in Mississippi

Abstract

Notropis longirostris (Hay), the longnose shiner, was studied in the Jourdan River system, Hancock and Pearl River counties, Mississippi, from May 1970 through May 1972. Occurrence of N. longirostris was significantly related to shore vegetation, bottom type, stream width, gradient and current. It was the most abundant species in stream sections characterized by large, open sandbars, clean, white, shifting sand bottoms, and a rapid fluctuation in flow rate and water depth. It occurred in the shallow areas along the edges of the sandbars where flow is low to moderate and the bank gradually slopes into the creek. Ammocrypta beani was most closely associated with N. longirostris although Notropis venustus was also commonly taken with the latter. The dominant food items were dipteran larvae, emerging or newly emerged dipterans, and other aquatic insects. Changes in foods with season were noted. Larger fish consumed a greater variety of food items. There was marked periodicity in diel feeding activity in May 1971. Feeding was most intensive during morning and early afternoon hours. INTRODUCTION Notropis longirostris, the longnose shiner, is a common cyprinid in coastal drainages from eastern Louisiana to western Florida and southwestern Georgia (Hubbs and Walker, 1942; Caldwell, 1966; Moore, 1968). Ramsey (1965) also reported this species from the Altamaha River drainage along the eastern coast of Georgia. It occurs over clean, shifting sand bottoms in shallow areas with low to moderate flow and is often the most abundant species in the stream sections it inlhabits. The habitat and reproduction of N. longirostris were reported on by Hubbs and Walker (1942). Moore (1944), Bailey et al. (1954) and Cook (1959) considered the life history and ecology of the species; however, the information available is incomplete. This study was undertaken as part of a larger investigation into the life history and ecology of this cyprinid (Heins, 1972). STUDY AREA Catahoula Creek (Fig. 1, stations 1-8), the main tributary of the Jourdan River drainage, originates in Pearl River Co., Miss., at an elevation ca. 71.6 m above mean sea level and flows S into W-central Hancock County. It is joined by Bayou Bacon to form the Jourdan River (Fig. 1, stations 9-12) which empties into St. Louis Bay. Stream gradients reach as high as 3.8-4.8 m/km in the 'headwaters and are less than 0.1 m/km in the lower sections of streams in the drainage. 1 Present address: Department of Biology, Tulane University, New Orleans, Louisiana 70118.