However, because of the small size of the fishery and the difficulty in securing additional research funds, no fishery-independent method of estimating biomass other than the DEPM was undertaken.
SP]) obtained with the DEPM have provided the biological basis for managing the Sardinops fisheries in WA for over a decade (Fletcher, 1991, 1995; Fletcher et al.
In a standard DEPM estimate, eggs are sampled in vertical net tows, starting from a point below the maximum depth of the eggs (typically 70 m) and ending at the surface.
Using the adaptive allocation survey design, we conducted a DEPM survey for Pacific sardine with a CUFES in 1997, and the precision of our estimate of daily production of eggs was compared with the precision of the estimate provided by a DEPM survey carried out in 1994 under standard methods (Lo et al.
To further minimize the random sampling error in these surveys, sampling effort could be increased, or modeled predictions of potential sardine habitat could be used to optimally plan both DEPM
and acoustic--trawl surveys, and thus save valuable time to increase sampling effort in areas of expected sardine presence.
The DEPM is a modeling system that allows the user to select both a consumption profile and a residue profile to infer population dietary exposure patterns.
To generalize the DEPM model run to the NHEXAS-Maryland foods, we matched the 131 foods in the NHEXAS-Maryland dietary checklist to foods in the NFCS database (22).
Acoustic estimates of sardine abundance compare well with those of the 2010 assessment but were higher than those of the DEPM (Fig.
Unlike the DEPM, acoustic-trawl surveys do not depend on the timing of spawning.
According to the April 2004 DEPM sardine survey off California, the large mature females, in particular those [greater than or equal to] 200 mm SL, were spawning very vigorously (S=0.
During the April 2004 DEPM survey, Pacific sardine were collected off central California between 34.
How ever, because the process of POF degeneration is continuous and DEPM
samples are usually obtained opportunistically throughout the day, the direct assignment of POF stages to daily classes of spawning fish can be imprecise.