OBSERVATIONS ON A POPULATION OF 
SIALIS ITASCA ROSS IN WEST VIRGINIA 
(MEGALOPTERA: SIALIDAE) 
By C. K. Lilly 1 , D. L. Ashley 2 , and D. C. Tarter 2 
Observations on the ecology of each species in an aquatic 
community are necessary for the total understanding of community 
dynamics. Several authors, including Davis (1903), Ross (1937), 
Townsend (1939), Flint (1964), Azam and Anderson (1967), Wood- 
ruin and Tarter (1973), Pritchard and Leischner (1973), Tarter and 
Woodrum (1973), Tarter (1973), Tarter et al. (1976), and Tarter et 
al. (1978) have reported on the taxonomy, distribution, life history, 
and ecology of several Sialis spp. Other authors, including Roback 
and Richardson (1969), Warner (1971), Nichols and Bulow(1973), 
Tarter and Woodrum (1972) and Woodrum and Tarter (1973), have 
noted the extreme tolerance of Sialis to acid mine drainage. 
The primary objectives of this investigation were: (1) to make 
observations on the life history and ecology of the alderfly S. itasca 
in a small farm pond and (2) to determine the pH tolerance of this 
population under laboratory conditions. 
Materials and Methods 
The population of S. itasca inhabits a small farm pond, 0.1 
hectare, near Shoals, West Virginia which is 8 km south of 
Huntington, West Virginia. This pond is located in the north-central 
region of Wayne County. It is located at 82°29'40"W longitude and 
38°21'50"N latitude. 
This investigation was initiated in May 1975 and continued until 
April 1976. Monthly samples were taken by a small seine (0.25 inch 
mesh). The seine was placed in the water vertically and the mud and 
debris on the bottom of the pond between the seine and the bank 
were disturbed. The seine was then moved toward the bank while 
dragging the bottom of the net on the bottom of the pond collecting 
■Present address: 4074 - 40th Street, Nitro, WV 25143 
2 Dept. of Biol. Sci., Marshall Univ., Huntington, WV 25701 
Manuscript received by the editor August 1, 1978. 
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