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The effects of aging bias on stock assessment have been evaluated in many simulation studies. However, simulated data cannot be used to quantify the magnitude of aging biases in a real data set and thus their effects on an ongoing stock assessment. In this study, we validated scale and otolith aging using Striped Bass Morone saxatilis of known age collected from the Chesapeake Bay between 1997 and 2006. Otoliths provided more accurate (74% agreement) and precise (average CV = 1.9%) age estimates than scales, which overestimated the ages of young fish and underestimated the ages of old fish (22% agreement; average CV = 9.8%). Based on their accuracy, otolith ages were subsequently used to quantify aging biases in the scale ages and effects of bias in the stock assessment of Atlantic Striped Bass. We converted scale‐age to otolith‐age input using paired scale and otolith ages of Striped Bass collected by commercial fisheries in Virginia waters of the Chesapeake Bay and the mid‐Atlantic from 1999 to 2010. A statistical catch‐at‐age model was run with the scale‐ and otolith‐age input data and the results were compared. We found that aging biases from scale ages resulted in underestimates of population abundance (15%) and female spawning stock biomass (19%) and overestimates of fishing mortality in the terminal year (19%) and made strong age‐1 recruitment years appear weaker and weak ones stronger. Our study demonstrates how aging bias in a large scale‐age sample can be corrected with a relatively small sample of paired scale–otolith ages and provides fisheries management with a quantitative evaluation of aging bias and its effects on the assessment of the Atlantic Striped Bass stock. [ABSTRACT FROM AUTHOR]

More than 60 stranded bottlenose dolphins Tursiops truncatus exhibiting marks consistent with interactions with pound nets have been documented in the lower Chesapeake Bay since 1997. Given this high rate of bycatch, action is needed to mitigate bottlenose dolphin mortality. However, for any such modification to the pound net to be acceptable to fishers, a clear demonstration of no reduction in the targeted finfish catch will be required. Working with fishers, we evaluated the effect of an experimental pound net leader on finfish catch. The experimental leader entailed similar or greater catches of finfish than did the traditional leader. Further, catches of Batoidea (cownose ray Rhinoptera bonasus, bullnose ray Myliobatis freminvillei, southern stingray Dasyatis americana and Atlantic stingray D. sabina) and clearnose skates Raja eglanteria were reduced with the experimental leader. This example demonstrates that working with fishers to devise alternative harvest strategies can result in the implementation of conservation measures. Although finfish catch was maintained with the experimental leader design, we must continue to monitor bottlenose dolphin bycatch to confirm that the use of the experimental leader reduces the bottlenose dolphin mortality associated with pound nets. [ABSTRACT FROM AUTHOR]

The article compares fish ingress abundancies of croaker larvae in Chesapeake Bay with the more accepted larval fish ingress model from published distribution patterns in barrier inlets. Analysis of variance (ANOVA) was made to assess the spatial patterns in 38 sampling stations at the mouth of the bay and adjacent coastal areas. Distribution patterns from statistical data gathered showed that croaker larvae abundance is largely affected by net depth and length as well as age distribution varies in nearshore stations. Results also reveal that ingress in the mouth of the bay is affected by mechanisms dissimilar from that in barrier island inlets. However, light responses were variable wherein croaker larvae far from offshore showed no response to light.