RAMP data from field observations

Data for fish and crabs show examples of how reflex impairment observations can be made during commercial fleet operations to estimate unobserved mortality.  With RAMP methods, experiments can be conducted by the fleet that identify important controlling factors for decreasing unobserved animal mortality from discarding and interactions with fishing gear. 

Davis 2002

Even though RAMP estimates for mortality in commercial fisheries may not presently have absolute accuracy, they are useful for identifying parts of fishing processes that have major impacts on unobserved mortality rates.  Carefully designed and fleet-inclusive observations of reflex impairment and RAMP during fishing, as well as experiments with gear configurations and deployment in different areas, seasons, and times of the day will certainly contribute to essential knowledge for fisheries management and allocation of scarce research and fishery resources.  Other sources for variability in RAMP scores and mortality estimates (predators, disease, and observer bias) may be evaluated using concurrent tagging of animals to compare RAMP estimated mortality rates versus tagging estimated mortality rates.  

Seasonal patterns were evident in RAMP scores and discard mortality for fish caught in the Georges Bank scallop fishery; for winter flounder,

and for yellowtail flounder.

Seasonal patterns of mortality related to windchill and temperature were evident in the snow crab fishery.

An experimental study by Rose et al. 2013 quantified RAMP and unobserved mortality for crabs that were encountered by bottom trawls in the Bering Sea. 

RAMP and corresponding mortality rates for snow crab, southern tanner crab, and red king crab.

Effects of trawl gear components on RAMP for crabs.

Effects of trawl gear components on mortality rates for crabs.