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Fishery Bulletin 107(4) 
s o^° d 
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Month 
0 March 
April-June 
July 
1 August 
® September 
® October 
♦ November 
100 
kms 
76 75 
Longitude (°W) 
Figure 5 
Seasonality and numbers of captures of adult (age-4+) 
red drum ( Sciaenops ocellatus) caught in coastal North 
Carolina, Virginia, and Maryland. Data are from the 
National Marine Fisheries Service trawl surveys, Virginia 
Institute of Marine Sciences shark longline surveys, or 
from fish tagged or recovered in the North Carolina Divi- 
sion of Marine Fisheries tagging project (1983-2007). The 
National Marine Fisheries Service survey took place in 
U.S. east coast continental shelf waters from Gulf of Maine 
to just south of Cape Hatteras in spring (March) and fall 
(September-November) each year in 1972-2004, and the 
Virginia Institute of Marine Sciences survey Virginia 
Institute of Marine Sciences survey was conducted in 
Chesapeake Bay and coastal Virginia waters in May or 
June through September or October, 1974-2004. 
developed a series of intuitive figures (e.g., circular map- 
ping) to summarize the ways in which the movement 
patterns of an estuarine fish species were influenced by a 
variety of factors. Our results have implications for stock 
structure, gene flow, and ultimately, the connectivity of 
estuarine fish populations. 
Movement patterns of red drum were distinctly age- 
dependent. Rates of movement generally declined with 
age, although the estimates for adult fish may be low if 
Month 
Figure 6 
Seasonal ultrasonic telemetry information for age-2 
red drum (Sciaenops ocellatus ) in Hancock Creek, 
2005-07. (A) Proportion of transmitter-tracked red 
drum emigrating each month from Hancock Creek, 
combined across years. (B) Proportion of tracked red 
drum moving upstream, downstream, or remaining 
stationary within Hancock Creek, combined across 
years. 
these adult fish were encountered mostly in estuarine 
waters after returning to spawn. From a physiological 
perspective, red drum are expected to show preferences 
for higher salinity with age (Neill et al., 2004), which 
may at least partially explain the observed age-depen- 
dent movement patterns towards the coast. Red drum 
are also known to experience major ontogenetic shifts 
in diet and habitat use (Bacheler et ah, 2009b), but it is 
unknown how these ecological shifts translate to age- 
dependent and seasonal movement patterns. Although 
movement rates of many fish species have been shown 
to be age-dependent (e.g., Skalski and Gilliam, 2000), 
previous work on the movements of red drum focused on 
only one age class (Dresser and Kneib, 2007) or found 
no differences among age groups (Osburn et ah, 1982). 
The observation that red drum movement patterns are 
age-specific is important for explaining age-specific se- 
lectivity patterns of the fishery (Bacheler et ah, 2008a). 
In addition, the timing of movement for each age class 
can also be used to create temporal closures as a fishery 
management tool to protect red drum during particu- 
larly vulnerable periods when movement rates are high 
(e.g., to protect them from passive gear like gill nets). 
