118 



Abstract — Examination of 203 adult 

 bluefish iPomatomus saltatrix) from 

 Long Island, New York, in 2002 and 

 2003 and 66 from the Outer Banks, 

 North Carolina, in 2003 revealed 

 the presence of dracunculoid nem- 

 atodes (PhiloinetJ-a saltatrix) in 

 the ovaries of female fish. Percent 

 prevalence reached 88% in July and 

 then decreased after the peak of the 

 spawning season. Bluefish contained 

 up to 100 parasites per fish. Infec- 

 tion was associated with a range of 

 disorders, including hemorrhage, 

 inflammation, edema, prenecrotic 

 and necrotic changes, and follicular 

 atresia, that may prevent proper de- 

 velopment of oocytes and probably 

 affect bluefish fecundity. Historical 

 occurrences, life cycle, and geographi- 

 cal distribution of this nematode 

 remain largely unknown, but may 

 play important roles in recruitment 

 processes of bluefish. 



Prevalence, intensity, and effect of 

 a nematode iPhilometra saltatrix) 

 in the ovaries of bluefish iPomatomus saltatrix) 



Lora M. Clarke 



Marine Sciences Research Center 

 Stony Brook University 

 Stony Brook, New York 11794-5000 

 E-mail address Lora ClarkefQ*msrc sunysb edu 



Alistair D. M. Dove 



Department of Microbiology and Immunology 



Cornell College of Veterinary Medicine 



c/o Marine Sciences Research Center 



Stony Brook University, Stony Brook, New York 11794-5000 



David O. Conover 



Marine Sciences Research Center 



Stony Brook University 



Stony Brook, New York 11794-5000 



Manuscript submitted 14 July 2004 

 to the Scientific Editor's Office. 



Manuscript approved for publication 

 25 July 2005 by the Scientific Editor. 



Fish. Bull. 104:118-124 (2006). 



Factors influencing recruitment vari- 

 ability in marine fishes are often com- 

 plex and poorly understood. Slight 

 variations in mortality rates, growth 

 rates, and stage durations in the 

 early life stages can result in tenfold 

 or greater fluctuations in abundance 

 (Houde, 1987). Recruitment variation 

 appears to be driven by a combina- 

 tion of factors, such as environmental 

 and oceanographic processes (Munch 

 and Conover, 2000), diet (Friedland 

 at al., 1988; Marks and Conover, 

 1993; Juanes and Conover, 1995), 

 growth and development (McBride 

 and Conover, 1991; Hare and Cowen, 

 1997) and habitat use (Able et al., 

 2003). The importance of parasitism 

 and disease has, however, seldom been 

 considered. 



In the Northwest Atlantic, the 

 bluefish [Pomatomus saltatrix) is dis- 

 tributed from Florida to the Gulf of 

 Maine and is both commercially and 

 recreationally important. This highly 

 migratory species has at least two 

 distinct spawning seasons. The first 

 occurs in the spring, from March to 

 May, south of Cape Hatteras, North 

 Carolina (NO (Kendall and Walford, 

 1979; Collins and Stender, 1987) and 



the second occurs off the coast of New 

 York (NY) from late June to August 

 (Norcross et al., 1974; Sherman et 

 al., 1984), peaking in July (Chiarella 

 and Conover, 1990). Ichthyoplankton 

 surveys have indicated that a third 

 spawning event occurs south of Cape 

 Hatteras, NC, in the autumn, but 

 juveniles spawned during this time 

 frame have rarely been captured (Col- 

 lins and Stender, 1987). 



During the collection of bluefish 

 ovaries for another study, the nema- 

 tode Philometra saltatrix Ramach- 

 andran, 1973 was detected in the 

 ovaries of adult bluefish. Previous 

 studies of Philometra spp. in other 

 host species have indicated that their 

 presence can have a negative effect 

 on fecundity (Oliva et al., 1992; Hesp 

 et al., 2002), implying that a more 

 complete understanding of parasites 

 may be important to understanding 

 reproductive success. Although fac- 

 tors such as female size and condi- 

 tion are often considered in deter- 

 mining reproductive success, the role 

 of parasitism is rarely investigated 

 (Marshall et al., 1998; Marteinsdottir 

 and Begg, 2002). The potential effect 

 of this nematode on the reproductive 



