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Fishery Bulletin 107(4) 
created within the circular plot. Age-1 and age-2 red 
drum were examined only in these plots because of low 
sample sizes of older age classes. The overall length of 
each wedge in the plot was the relative frequency of an- 
gular observations within 20° bins scaled to the largest 
number for each plot (because sample size was highly 
variable). Each wedge was further subdivided into the 
proportion of movements in various distance categories. 
These unique diagrams allowed for an examination of 
both direction and distance moved by season for red 
drum. 
Anecdotal reports have indicated that some adult 
(age-4+) red drum migrate from coastal North Carolina 
waters northward each spring to Virginia and Mary- 
land, and return southward in the fall. We examined 
the hypothesis of a seasonal migration of adult red 
drum with data from three sources: 1) the National 
Marine Fisheries Service (NMFS) trawl surveys; 2) Vir- 
ginia Institute of Marine Sciences (VIMS) shark long- 
line surveys; and 3) locations of tagged and recovered 
adult red drum in coastal waters from North Carolina 
northward. The NMFS trawl surveys were conducted in 
spring (March) and fall (September-November) in coast- 
al waters from just south of Cape Hatteras northward 
(Despres-Patanjo et al., 1988); we used data from 1972 
to 2004. The VIMS shark longline surveys have been 
conducted in the lower Chesapeake Bay and Virginia 
coastal waters from May or June through September 
or October (Conrath and Musick, 2007), and data from 
1974 to 2004 were used. Data from these three sources 
were combined to provide a seasonally based map of 
adult red drum captures along the mid-Atlantic coast. 
Ultrasonic telemetry 
In order to quantify small-scale movements of subadult 
red drum, we also used ultrasonic telemetry data in 
a small lateral tributary of the Neuse River, Hancock 
Creek. Ultrasonic telemetry data were used in Han- 
cock Creek instead of over a broader area (e.g., Pamlico 
Sound) because of the accessibility of the creek, ease 
of tracking, and its narrow mouth that could be moni- 
tored with submersible receivers (see below). Age-2 red 
drum were implanted with transmitters in Hancock 
Creek between 2005 and 2007; the surgical procedures 
are described in Bacheler (2008). Fish were surgically 
implanted with coded ultrasonic transmitters (VEMCO, 
Ltd., Halifax, Nova Scotia, Canada; V16 4H, 10 g in 
water; 10 mm wide; 65 mm long) and were released 
after swimming behavior returned to normal (approxi- 
mately 10 minutes). Transmitter weight in water was 
always less than 1.25% of the fish’s body weight, as 
recommended by Winter (1996); there was no evidence 
that the transmitter affected the behavior of red drum 
in the laboratory or field (Bacheler et al., 2009a). The 
transmitters operated on a frequency of 69 kHz and 
were programmed to be continuously active for a period 
of 641 days. 
Transmitter-tagged red drum were manually tracked 
(relocated) monthly during daylight hours by using a 
VEMCO VR100 receiver and hydrophone. Upon relo- 
cation of a transmitter-tagged fish, the latitude and 
longitude coordinates were recorded, and water depth, 
temperature, salinity, and dissolved oxygen measure- 
ments were taken with a YSI® 85 (Yellow Springs In- 
struments, Inc., Yellow Springs, OH). Monthly move- 
ment rates were calculated as the shortest distance in 
water (km) between two successive relocation events. 
Upstream or downstream movements were determined 
for fish moving greater than 50 m in an upstream or 
downstream direction from its previous monthly loca- 
tion; otherwise, the fish was classified as stationary. 
In order to quantify the seasonality and magnitude 
of emigrations from Hancock Creek, submersible VR2 
VEMCO receivers were deployed at its mouth. Prelimi- 
nary testing indicated that VR2 receivers could detect 
nearly 100% of the pulses from V16 tags at 400 m in 
our study system (Bacheler, 2008). Therefore, three 
submersible receivers were deployed at the mouth of 
Hancock Creek, each being a conservative distance of 
600 m apart from one another. If a fish emigrated from 
the tributary, it was eliminated from the movement 
analyses. 
We were also interested in potential correlations 
between movements and emigrations of red drum in 
Hancock Creek. Preliminary observations of transmit- 
ter-tagged red drum in Hancock Creek indicated that 
fish often moved in synchronized ways upstream or 
downstream during monthly periods. To test for sea- 
sonal effects, we related the frequency of fish moving 
upstream, moving downstream, and remaining station- 
ary in Hancock Creek with the month of relocation, 
using an RxC test of independence. Given that the 
salinity regime in Hancock Creek was near the lower 
limit for red drum (i.e., 0-10 psu; Crocker et al., 1983; 
Forsberg and Neill, 1997), we also tested whether fluc- 
tuations in salinity were correlated with upstream and 
downstream movements, as well as with emigrations, of 
age-2 red drum. We correlated the proportion of tagged 
red drum moving upstream or downstream each month 
with the observed change in salinity near the midpoint 
(boat ramp) of Hancock Creek (see Fig. 1 for location) 
using Pearson’s product-moment correlation analysis. 
Months with sample sizes of less than four tagged red 
drum were excluded from analysis. 
Results 
Conventional tagging 
A total of 48,136 red drum (142-1473 mm total length) 
were tagged with conventional tags (i.e., internal anchor 
or dart) in this study, of which 6173 were recovered and 
reported by fishermen (Table 1). Overall, 58% of these 
recoveries were from fish tagged at age 1, 30% were 
from age 2, 2% were from age 3, and 9% were from 
age 4+ fish. A majority of recoveries occurred from fish 
originally tagged in the NPR (59%), but many fish were 
also recovered from releases in other regions as well 
