4. Fisheries and Marine Mammals

Bycatch of marine mammals in U.S. and global fisheries.

Fisheries bycatch poses a significant threat to many populations of marine mammals, but there are few published estimates of the magnitude of these catches. We estimated marine mammal bycatch in U.S. fisheries from 1990 to 1999 with data taken from the stock assessment reports required by the U.S. Marine Mammal Protection Act. The mean annual bycatch of marine mammals during this period was 621...

Marine and Coastal Fisheries

Pop-up satellite archival tags (n = 31) were deployed on Yellowfin Tuna Thunnus albacares in the Gulf of Mexico for periods ranging from 14 to 95 d. Differences in diel vertical behavior were assessed by comparing time spent at temperature relative to the surface temperature ( T). Pooled samples revealed that 31% of darkness hours, 20% of twilight hours, and 12% of daylight hours were spent in ...

Marine and Coastal Fisheries

—The ability of fish to submerge after discarding is often used as a proxy for survival, but this practice underestimates total discard mortality because delayed mortality is overlooked. Fishery managers need a way to link ‘‘sink or swim’’ indicators, or variables observed during capture and release, with delayed mortality rates. We conducted a cage study of red snapper Lutjanus campechanus off...

Daniel Pauly May 2004 Competition between Marine Mammals and Fisheries : FOOD FOR THOUGHT

Figure 1. Who Eats How Much of WHAT? Estimated mean annual global catch/food consumption of marine mammals and fisheries by 9 major food types during an average year in the 1990s expressed as proportions of total (from Kaschner, 2004) 138. The percentages of different food types in marine mammal consumption were computed based on diet composition standardised across species 96. Corresponding pe...

Fisheries and Marine Service Yuci