DEVELOPMENTAL INSTABILITY AS AN INDICATOR OF ENVIRONMENTAL-STRESS IN THE PACIFIC HAKE (MERLUCCIUS-PRODUCTUS)

Developmental Instability (DI) has been proposed as an inexpensive, qu ickly applied, and sensitive indicator of stress that can be utilized in early warning and in monitoring anthropogenic impacts on fish and o ther animals and plants. A problem arises, however, to the extent that natural stressors confound the effects of human-induced disturbances. Our objective in this work was, to investigate whether a natural stre ssor, in the form of El Nino conditions, contributed to DI in the Paci fic hake. Right-left (fluctuating) asymmetry of otolith length, width, growth rate, and weight, as well as right-left otolith shape differen ces, were used as measures of DI. Results show that indeed El Nino dis rupts development, indicating stress. This outcome suggests that DI, a s an early warning and monitoring tool for stress, must be used with c aution.