SEASONAL DISPERSAL AND HABITAT SELECTION OF GUNNER, 



TAUTOGOLABRUS ADSPERSUS, AND YOUNG TAUTOG, 



TAUTOGA ONITIS, IN FIRE ISLAND INLET, 



LONG ISLAND, NEW YORK' 



BoRi L. Olla, Allen J. Bejda, and A. Dale Martln^ 



ABSTRACT 



Results of field observations examining seasonal movements in the cunner, Tautogolabrus adspersus, 

 and young tautog, Tautoga onitis, showed a small portion of a resident population located off Fire 

 Island, N.Y., to disperse seasonally. Dispersal was from habitats which provide cover for both species 

 throughout the year to seasonal habitats occupied primarily during summer. While both species 

 exhibit a high degree of association with cover, results of experimental transfers of young tautog, 

 monitored either ultrasonically or directly by divers with self contained underwater breathing 

 apparatus, showed that fish will leave a suboptimal habitat even though cover is present. Dispersal and 

 habitat selection are discussed in relation to seasonal changes in the environment and ecological 

 requirements of the fish. 



Association with and dependence on cover by 

 marine fishes have been observed for a wide vari- 

 ety of species, exemplified by those which reside on 

 coral reefs (e.g,, see: Hobson 1968, 1972, 1973; Sale 

 1969a, 1971, 1972, 1977: Smith and Tyler 1972, 

 1973). Although the number of species is much 

 less, similar associations with cover also occur in 

 temperate waters (e.g., see: Hobson 1971; Bray 

 and Ebeling 1975; Hobson and Chess 1976; Olla et 

 al. 1974, 1975). 



In both tropical (Hobson 1968, 1972) and tem- 

 perate regions a major behavioral trait of the fam- 

 ily Labridae is that members show a strong as- 

 sociation with cover. Field studies on two 

 temperate-water labrids of the northwest Atlan- 

 tic, cunner, Tautogolabrus adspersus (Olla et al. 

 1975), and young tautog, Tautoga onitis (Olla et 

 al. 1974), have demonstrated their close associa- 

 tion with cover. Under laboratory conditions simi- 

 lar associations have been observed for both 

 species (cunner, Olla and Bejda unpubl. obs.; 

 young tautog, Olla and Studholme 1975). 



Over several years, incidental sightings of cun- 

 ner and young tautog always found them in as- 

 sociation with cover. However, it was apparent 

 that a substantial number offish were in areas in 



'This work was supported, in part by a grant from the U.S. 

 Department of Energy No. EX76-A-28-3045-A010. 



^Northeast Fisheries Center Sandy Hook Laboratory, Na- 

 tional Marine Fisheries Service, NOAA, Highlands, NJ 07732. 



Manu.script accepted October 1978. 

 FISHERY BULLETIN: VOL. 77. NO. 1. 1979. 



which cover was present only seasonally, e.g., 

 macroalgae and mussel beds. This suggested to us 

 that there must be movement to these areas some- 

 time after emergence from winter torpor (Olla et 

 al. 1974, 1975) in March or April and movement 

 away from these areas in the fall as the cover 

 provided at these areas diminished. The possibil- 

 ity of seasonal dispersal and habitat selection ap- 

 peared likely. At least for adult tautog changes in 

 habitat requirements with season have been es- 

 tablished, as evidenced by the fact the fish migrate 

 offshore to overwinter (Cooper 1966; Olla et al. 

 1974). 



In this study we have examined seasonal 

 movements in cunner and young tautog, basing 

 our observations on trapping and tagging, as well 

 as surveying shelter sites seasonally by direct ob- 

 servation with scuba or mask and snorkel. We also 

 performed a series of transfer experiments to 

 examine certain aspects of habitat selection. 



MATERIALS AND METHODS 



Based on previous scuba observations, six study 

 sites (A, B, C, D, E, and F; Figure 1) within Fire 

 Island Inlet, Long Island, N.Y., were selected at 

 which to monitor the seasonal movements of cun- 

 ner and young tautog. One site (A) was inhabited 

 throughout the year and will be referred to as a 

 perennial site. The five other sites (B, C, D, E, and 

 F) were utilized only during late April through 



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