SILLIMAN: EXPERIMENTAL EXPLOITATION OF FISH POPULATIONS 



Table 8.-Exploitation of competing populations. Rates are per brood interval: guppy, 3 wk; swordtail, 4 wk. 



biomass were simultaneously generated using 

 Formulae (7) and (8). A number of trials were 

 made on data from the control populations (Table 

 10) to find the most suitable values of the compe- 



tition coefficients c, and Cn 



Values of Ci = 0.071 



(guppy) and c, = 0.120 (swordtail) produced curves 

 (Figure 12) which fitted reasonably well except for 

 the oscillatory variations to be discussed below. 



Table 9.-Constants used in fitting simulation model to biomass data for competing populations. 



883 



