Able and Grothues: Diversity of the estuarlne movements of Morone soxatilis 



427 



Sweetwater 



Lower A. 

 Bank 



Garden State 

 Parkway 



New 

 Jersey 



t 



^1. . . PebDie 

 Chestnut B^3^, 



Neck 



/ 



Newman's 

 Ttiorofate, 



Sheepshead Little Egg w 

 Harbor \ 



Creek 



i 



yf Data logger 

 Q Hydroptione 



Study I — I 

 Area " — ' 



Long Beach 

 Island 



■^ ^k ^^ Snooting Thorofare 

 Channel^ g^ ■" ^^ -.^. .. 



39 30' N 



Little Egg Inlet 



Little 

 Beach 



LEO-15 

 • 



Atlantic Ocean 

 L_ 



Figure 1 



Mullica River-Great Bay study site and important localities (A) and location offish tagging and release 

 sites (B) during 2003 and 2004. Hydrophone 12 was not deployed during this period and is not shown. 



Hudson River (Secor et al., 2001; Zlokovitz et al, 2003) 

 or Chesapeake Bay (Secor, 2000a, 2000b). Relatively 

 little attention has been directed to small coastal bay 

 and estuarine systems that, owing to scale, may have 

 very different dynamics. 



The purpose of this study was to determine the an- 

 nual, seasonal, and episodic patterns of residency and 

 movements for large juvenile and adult striped bass 

 along an estuarine gradient in a small drowned-river- 

 valley estuary. Although most previous telemetry and 

 tracking studies focused on one fish at a time, the estu- 

 arine system used in the present study allowed for syn- 

 optic observations of numerous individuals. Throughout 

 this study there was an emphasis on individual behav- 

 ior, an approach that has provided important insight 

 into the stock structure of other fishes (Sutherland, 

 1996; Slotte and Fiksen, 2000). 



Materials and methods 



2004). This relatively small watershed (1474 km^; Ken- 

 nish, 2004) that comprises several tributaries (Batsto, 

 Wading, and Bass Rivers) is part of the Jacques Cous- 

 teau National Estuarine Research Reserve (JCNERR) 

 and drains the Pinelands National Reserve at a mean 

 monthly stream flow of approximately 1.7 to 4.2x10* 

 L/d (Rhodehamel, 1998) (Fig. 1). Much of the 280 km of 

 shoreline in this watershed consists of cordgrass (Spar- 

 tina alterniflora) dominated salt marsh, and has a tidal 

 range between 0.7 m (in Little Egg Harbor) and 1.1 m 

 (near the mouth of Great Bay). Mean salinity of 29 at 

 the entrance to the bay drops sharply to about 8 within 

 30 linear km upriver; the inflection point corresponds 

 to a steep decrease in pH from 8.0 to 6.0 owing to tan- 

 nins leached from the pine-forested watershed (Ken- 

 nish, 2004). The majority of water exits into the ocean 

 through the narrow but deep (20 m) Little Egg Inlet and 

 to a lesser extent through the Main Marsh Thorofare, 

 an intra-estuarine connection that is part of the Intra- 

 Coastal Waterway (ICW) (Chant et al., 1996). 



Study site 



The Mullica River-Great Bay estuary (Fig. 1) is one of 

 the few remaining relatively undisturbed estuaries in 

 the northeastern United States because there is little 

 agricultural or industrial development in the watershed 

 and human population density is relatively low (Kennish, 



Estuarine observatory 



Wireless hydrophones were deployed at a series of gates 

 in order to enhance detection of tagged striped bass 

 while in residence or moving along the estuarine gradi- 

 ent (Fig. 1). At the entrance to the estuary (Little Egg 

 Inlet) hydrophones 2, 3, and 4 (recorded as positioned 



