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Fishery Bulletin 99(4) 
of assumptions. First, we assumed herding efficiency was 
independent of bridle length. If, however, exhaustion was 
a primary determinant of bridle efficiency, then it is pos- 
sible that individual endurance would be exceeded more 
Mode! assumptions 
The adequacy of the herding model and the appropriate- 
ness of our herding efficiency estimates rest on a variety 
