Mortality in gillnets has long been recognized as the most serious and immediate threat to the vaquita’s survival.
Gill nets of various mesh size for fish and shrimp cause incidental mortality (bycatch) of vaquitas. The only available estimates of the vaquita bycatch rate are 39 (using one method) and 84 (using a different method) animals killed per year by boats from a single port. This alone would represent 7 or 15%, respectively, of the estimated total population size.
Sources: (D’Agrosa, Lennert-Cody, & Vidal, 2000), (EIA, 2016), (NOAA, 2008), (Rojas-Bracho, Reeves, & Jaramillo-Legorreta, 2006), (Rojas-Bracho, Reeves, Jaramillo-Legorreta, & Taylor, 2008), (Rojas-Bracho & Taylor, 1999), (Vidal, 1995)
Image: Omar Vidal, NOAA Fisheries West Coast