Estimating discharge rates of oily wastes and deterrence based on aerial surveillance data collected in western Canadian marine waters

► Detection rates for oily discharges were modeled with aerial surveillance effort. ► Rates were modeled for data summarized monthly, bimonthly and annual quarters. ► Logistic regressions performed better than linear regressions for modeling rates. ► Quadratic component in best fit logistic models indicate possible deterrence effect. ► Annual discharge rates declining based on best fit logistic regression residuals.