Construction of a 110-year biochronology from sagittae of freshwater drum (Aplodinotus grunniens)
D.L. Pereira, C. Bingham, G.R. Spangler, D.J. Conner, and P.K. Cunningham. 1993. Construction of a 110-year biochronology from sagittae of freshwater drum (Aplodinotus grunniens). Proceedings of the International Symposium on Fish Otolith Research and Application.
Abstract
Freshwater drum (Aplodinotus grunniens) in the Red Lakes, Minnesota are long-lived and exhibit episodic recruitment. Fish as old as 71 years were obtained from samples archived in 1951. The oldest fish obtained from contemporary samples are of the 1930 year class. We detrended allometric growth of saggital otolith increments with an exponential model. We then aligned residuals from individual fish to calendar years to establish a growth history. We also compare growth between year classes and contrast growth time series from three hierarchical arrangements of the data. We have used this otolith growth history as a biochronology to infer stock dynamics, past environmental conditions, and to establish correlation with climate.