Blue runner, continued 



Adams pers. comm., Nelson et al. 1 992). Within U.S. 

 estuaries of the Gulf of Mexico, the blue runner ap- 

 pears to be most common along the west coast of 

 Florida (Table 5.27) (Heald 1970, Fischer 1978), and 

 not generally common in estuaries west of the Missis- 

 sippi River (Shaw and Drullinger 1990, Adams pers. 

 comm., Cambell pers. comm., Rice pers. comm.). 

 However, larval data suggest that blue runner are 

 common in coastal marine waters west of the Missis- 

 sippi River (Ditty pers. comm.) 



Life Mode 



This is a pelagic, fast-swimming species (Goodwin and 

 Johnson 1 986). Early life stages are planktonic. Late 

 juveniles form small schools in and at the edges of the 

 Florida Current (McKenney et. al. 1958). Adults usu- 

 ally form schools, although larger individuals will re- 

 main solitary (Nichols 1938, Goodwin and Finucane 

 1985). 



Habitat 



Type : The blue runner is neritic and oceanic inhabiting 

 primarily tropical and warm waters surrounding conti- 

 nents or large islands (McKenney et. al. 1 958, Goodwin 

 and Johnson 1986). In the Atlantic Ocean off the 

 southeastern U.S., larvae and juveniles inhabit off- 

 shore waters in association with the Gulf Stream (Berry 

 1 959). The larvae of blue runner are present in the Gulf 

 Stream from May through November and are in great- 

 est abundance from mid-June to mid-August (Fable et 

 al. 1 981 , Shaw and Drullinger 1 990). Larvae are found 

 in the Gulf of Mexico from April through August (Ditty et 

 al. 1 988), and the greatest numbers occur in the central 

 region, where they are found in waters over the conti- 

 nental shelf (Shaw and Drullinger 1990). Juveniles 

 occur over deep water, but are usually present in the 

 upper 100 m of the water column (McKenney et al. 

 1958). However, they have been known to occur in 

 depths of 1 80 m or greater (Johnson 1 978). Individuals 

 greaterthan 1 00 mm SL inhabit the shelf and nearshore 

 waters of the Atlantic coast, and peak in abundance 

 during June and July (Berry 1 959, Dooley 1 972, Johnson 

 1978, Goodwin and Johnson 1986). Early juveniles 

 are associated with floating objects such as sargas- 

 sum seaweed or jellyfish, and acquire a cryptic colora- 

 tion during this period (Nichols 1 938, Lindall et al. 1 973, 

 Johnson 1978, NOAA 1985, Shipp 1986). 



Substrate : Because this species is pelagic, it occurs 

 over a wide variety of substrates (NOAA 1985). 



Physical/Chemical Characteristics 

 Temperature: Recently hatched larvae (<2.5 mm SL) 

 occur in water surface temperatures of 28.8°-30.1° C 

 (Shaw and Drullinger 1990), while larvae of all sizes 

 occur in thermal habitats of 20.4-32°C (Johnson 1 978, 

 Shaw and Drullinger 1990). Juveniles are found at 



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