152 
Fishery Bulletin 115(2) 
Year day 
Figure § 
Acoustic detections of an age-l-f- blueflsh (Pomatomus 
saltatrix) that was 635 mm in total length and tracked 
in 2007 in the Navesink River, New Jersey. Dashed 
lines indicate geographical locations at the given dis¬ 
tances from the mouth of this river. 
estuaries (core areas with diameters of 0.5-1.0 km) in 
New Jersey (Grothues and Able, 2007; Ng et al., 2007; 
Able et al., 2012; Turnure et al., 2015). Striped bass in 
the Hudson River were tracked over many kilometers, 
but their movements occurred seasonally rather than 
daily (Wingate and Secor, 2007). 
Within the home range of an individual fish, irregu¬ 
lar diel or tide-related movements >1 km were noted in 
both 2006 and 2007 (Fig. 6). Results of general additive 
modeling with the 2006 telemetry data indicate that 
some of the variability in the daily positions was at¬ 
tributable to tide or time of day, but the telemetry data 
were complex and unclear because of extreme variabil¬ 
ity among individual fish (Manderson et al.^). 
The results of the analysis of data from telemet¬ 
ric tracking augmented the results of the analysis 
of data from gill net sampling, showing that home 
ranges of the 3 predator species were not localized or 
limited to the area of the salinity front in the west 
of the Navesink River. Undoubtedly, the gill net sam¬ 
pling in 2007 did not provide a complete picture of 
the use of the Navesink River by the 3 predators be¬ 
cause the gill nets were placed only in the upper riv¬ 
er, separated by a distance of about 2 km. However, 
our study was designed on the basis of the results of 
the Scharf et al. (2004) study in which gill nets were 
used throughout the river. In that study, the greatest 
abundances of blueflsh and weakfish in all 3 seasons 
occurred at their station 13 (close to the Red Bank 
basin, reach 4 in our study), and secondarily at sta¬ 
tion 10 (in the lower river near the mouth of Claypit 
Creek, reach 2 in our study) (Scharf et al., 2004; se¬ 
nior author, unpubl. data). 
Combining hydrography, gill-net sampling, and te¬ 
lemetry allowed us to investigate the use of the estua¬ 
rine habitat by the 3 dominant predators on a variety 
of temporal and spatial scales. Environmental forcing, 
as discussed in Manderson et al. (2014), broadly con¬ 
trols the residence times of fish in the Navesink River. 
Wfithin the time of its estuarine residence, a fish uses 
a home range for a duration of days or weeks. Stomach 
contents are representative of the activity of about 1 d, 
and telemetric data shed light on hourly, daily, and sea¬ 
sonal activities. Hydrographic investigations detect ar¬ 
eas where high chlorophyil-a concentration is favorable 
for zooplankton growth, and gill net sampling pinpoints 
concentrations of piscine prey. Tracks of individual fish 
show short-term diel or tide-related upriver and down¬ 
river movements of about 1 km, but further analyses of 
these movements would be needed to discover whether 
they originate from tides, light availability, prey pres¬ 
ence, or a suite of influences. We determined that even 
in a small, lO-km^ estuary, multiple reaches of the 
Navesink River system contain habitat of the quality 
needed to support the survival and growth of blueflsh, 
weakfish, and striped bass from days to months. These 
advantageous habitats change in location with the 
seasons and are not limited to the estuarine turbidity 
maximum or the main salinity transition front. 
Acknowledgments 
We thank our current and former colleagues, particu¬ 
larly from the Fisheries Ecology Branch of the NOAA 
Northeast Fisheries Science Center at the James J. 
Howard Marine Science Laboratory: B. Phelan-Hill, P. 
Plantamura, J. Rosendale, and V. Guida for their work, 
criticisms, and improvements to the experimental de¬ 
sign and the manuscript. We are grateful to volunteers, 
summer employees, and graduate students. Unpub¬ 
lished data from surveys conducted by the Fisheries 
Ecology Branch were used to broaden our knowledge 
of the area and scope of work. We also thank K. Hart¬ 
man of West Virginia University, Morgantown, West 
Virginia, J. Jacobs of the Cooperative Oxford Labora¬ 
tory, Oxford, Maryland, and anonymous reviewers for 
their valuable contributions. 
Literature cited 
Able, K. W., T. M. Grothues, J. T. Turnure, D. M. Byrne, and 
P. Clerkin. 
2012. Distribution, movements, and habitat use of small 
striped bass {Morone saxatilis) across multiple spatial 
scales. Fish. Bull. 110:176-192. 
Anderson, D. J. 
1982. The home range: a new nonparametric estimation 
technique. Ecology 63:103-112. 
