Abstract. — Aerial surveys for 

 sea turtles conducted in Core 

 Sound and Pamlico Sound, North 

 Carolina, 1989-91, indicated a 

 spring immigration by the turtles 

 into these sounds and a summer- 

 time dispersal followed by emigra- 

 tion in the late fall and early win- 

 ter. Estimates of density in Core 

 Sound were greater than estimates 

 for Pamlico Sound. Core Sound 

 density estimates were comparable 

 to those reported for the lower 

 Chesapeake Bay and those re- 

 ported from offshore pelagic sur- 

 veys in the region. The data were 

 analysed by strip- and line-transect 

 methods, and the choice of analy- 

 sis did not influence the overall 

 conclusions. The abundance of sea 

 turtles in the inshore waters of the 

 Atlantic Coast at densities at least 

 as great as in the ocean indicates 

 the importance of these estuarine 

 habitats for the foraging and devel- 

 opment of immature turtles. 



Aerial surveys for sea turtles in 

 North Carolina inshore waters 



Sheryan R Epperly 

 Joanne Braun 

 Alexander J. Chester 



Beaufort Laboratory, Southeast Fisheries Science Center 

 National Marine Fisheries Service. NOAA 

 Beaufort. NC 285 1 6 



Manuscript accepted 25 September 1994. 

 Fishery Bulletin 93:254-261 (1995). 



Recent studies have demonstrated 

 the importance of inshore waters as 

 developmental and foraging habi- 

 tats for threatened and endangered 

 sea turtles along the Atlantic Coast 

 of the United States (e.g. Medonca 

 and Ehrhart, 1982; Ehrhart, 1983; 

 Lutcavage and Musick, 1985; Kein- 

 ath et al., 1987; Burke et al., 1992, 

 1993). A study of sea turtles in 

 North Carolina waters used sight- 

 ings reported by the public and 

 documented the importance of 

 Pamlico and Core Sounds for imma- 

 ture loggerhead, Caretta caretta; 

 green, Chelonia mydas; and Kemp's 

 ridley, Lepidochelys kempii, sea 

 turtles (Epperly et al., in press, a). 

 As part of the same study, aerial 

 surveys were employed over a 3-yr 

 period to provide independent quan- 

 titative verification of the impor- 

 tance of Pamlico and Core Sounds 

 as sea turtle habitats. 



We report the results of the aerial 

 survey work in Pamlico and Core 

 Sounds, part of the largest estua- 

 rine system in the southeast United 

 States. Once aerial survey method- 

 ology was validated in inshore wa- 

 ters, our goals were 1) to obtain in- 

 dependent evidence for the season- 

 ality and distribution patterns of 

 turtles obtained from other sources, 

 2) to quantify the abundance of sea 

 turtles in the sounds and compare 

 those densities with other areas, 

 and 3) to evaluate the consequences 

 of the application of line vs. strip 

 survey methodology to the data. 



Materials and methods 



Aerial surveys of Core and 

 Pamlico Sounds 



Pamlico and Core Sounds were di- 

 vided into three areas (Fig. 1): Core 

 Sound (34°41'N to 35°00'N), south- 

 ern Pamlico Sound (35°00'N to 

 35°20'N), and northern Pamlico 

 Sound (35°20'N to 35°48'N). Areas 

 of each were 248 km 2 , 2,501 km 2 , 

 and 1,951 km 2 , respectively. The 

 divisions were, in part, based on 

 geography and on facilitating access 

 to restricted airspace. In Core 

 Sound, each flight surveyed ap- 

 proximately 26% of the total surface 

 area of the sound (32, rarely 33 

 transects); for both southern and 

 northern Pamlico Sound, approxi- 

 mately 6% of the total area was sur- 

 veyed (8 transects in southern 

 Pamlico Sound and 11 transects in 

 northern Pamlico Sound). Surveys 

 were taken from a Cessna 172 (from 

 a side-viewing platform) at 128 km/ 

 h and at an altitude of 152 m. This 

 altitude was chosen as a compro- 

 mise between areal coverage and 

 the ability to sight smaller turtles 

 on the surface of inshore waters. 

 Surveys were scheduled so that lo- 

 cal apparent noon occurred approxi- 

 mately half-way through the survey. 

 Surveys were undertaken only if 

 winds were less than 28 km/h and 

 seas were less than 0.6 m with no 

 or few whitecaps (e.g. Beaufort Sea 

 State <2). We attempted to perform 



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