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Fishery Bulletin 112(2-3) 
Figure 1 
Map of the study area in the Navesink River, New Jersey, on the northeastern coast of the United 
States and the locations of the 32 moorings with ultrasonic receivers (white circles) and sensors 
(dark symbols) that measured the physical environment in the study area in which we captured, 
released, and monitored the movements of tagged Striped Bass (Morone saxatilis), Bluefish (Poma- 
tomus saltatrix), and Weakfish ( Cynoscion regalis) in 2006 and 2007 for a study of residence times 
and duration of habitat suitability for these 3 predators. The 5 moorings added in 2007 are indicated 
by asterisks. A, B and C labels indicate the locations referred to in the text and in the legend for 
Figure 2. Instruments deployed with receivers included temperature, salinity, pressure, and dis- 
solved oxygen sensors from YSI, Inc., temperature, salinity, and pressure sensors from Star-Oddi, 
and an RCM-9 meter from Aanderaa Data Instruments that measured current speed and direction, 
temperature, salinity, pressure, and optical backscatter. Measurements of freshwater discharge were 
made at the U.S. Geological Survey (USGS) stream flow station in the Swimming River. 
ity, temperature, and depth (CTD) sensor. In 2007, we 
performed additional hydrographic surveys associated 
with gillnet surveys of predators and prey in the up- 
per river. 
Measurements of freshwater discharge (in me- 
ters per second) from the Swimming River were 
made at the U.S. Geological Survey stream flow sta- 
tion (http://nwis.waterdata.usgs.gov/nj/nwis/uv/7site_ 
no=0 1407500&PARAmeter_cd= 00065,00060). Baro- 
metric pressures, wind, and air temperatures were 
measured 7.5 km from the study area at the NOAA 
weather station in Sandy Hook, New Jersey (http:// 
www.ndbc.noaa. gov/station_page.php?station=sdhn4). 
Ultrasonic tagging 
From May 14 to September 8, 2006 and from May 1 to 
October 2, 2007, we used hook and line to capture age- 
1+ Striped Bass, age-0 and age-l+ Bluefish, and age-l-f- 
Weakfish as seasonally available within the footprint of 
the estuarine observatory (Table 1). On the basis of pub- 
lished age-length relationships, we divided Bluefish into 
age-0 and age-l+ age classes at a total length of 290 mm 
(Chiarella and Conover, 1990; Munch and Conover, 2000; 
Scharf et al., 2004). We transported fishes to the James 
J. Howard Marine Sciences Laboratory in Highlands, 
New Jersey, for internal tagging. Fishes were held <8 
days (d) in tanks (2.5-m diameter, 0.35-m depth) sup- 
plied continuously with ambient estuarine water. We 
anaesthetized fishes with AquiS (AquiS New Zealand, 
Ltd., Lower Hutt, New Zealand) at a concentration of 
54 mg/L. Duration of anesthesia averaged ~3 min. 
After a fish was anaesthetized, we made an incision 
1-2 cm long on its ventral midline and inserted into 
the body cavity a sterilized, uniquely coded ultrasonic 
transmitter (V9-6L with a frequency of 69 kHz, rep- 
etition rate of 40-120 s, dimensions of 9 mmx20 mm, 
weight of 2 g in water, and minimum battery life of 110 
d; VEMCO). We closed incisions with 2 or 3 nylon su- 
tures (Ethilon 30 and 40 with FS1 cutting needle, Ethi- 
