NORMS and DOHL: BEHAVIOR OF THE HAWAHAN SPINNER DOLPHIN 



absent from others. This led us to collect sighting 

 and capture locations for the entire Hawaiian 

 chain. The same collectors reported that after col- 

 lection of animals from a given school, the school 

 as a whole might become shy of the boat for an 

 indefinite period, and suggested that it occupied a 

 given area of coast and the school might have 

 integrity through time. 



We found that spinner dolphins occur through- 

 out the Hawaiian chain, from its northwest- 

 emmost limit at Kure Atoll (lat. 25°40' N, long. 

 175°38 ' W) to its southernmost limit at South Point, 

 or Ka Lae, on the island of Hawaii (lat. 18°49' N, 

 long. 155°41' W). Occurrence is not random, but 

 spinner dolphins are gathered in small to moder- 

 ate schools (6 to about 250 animals) near all major 

 islands and shoal areas and can be found with 

 some regularity near certain shoals or coves. Only 

 near small islands that drop abruptly without 

 having significant shoals, such as at Nihoa Island, 

 have we not found spinner dolphins. The following 



is a synopsis of known spinner distribution. Un- 

 less othervnse specified, all sightings were by the 

 authors. Specific records are shown in Figure 3. 



Kure Atoll. On 3 September, 1971, Norris vis- 

 ited Kure Atoll. The commanding officer, Lt. (j-g) 

 Joel Greenberg, reported having seen a school of 

 20-30 spinner dolphins enter a west pass into the 

 atoll lagoon. Without prompting he described 

 their spinning behavior. 



Midway Island. On the midaft;ernoon of 3 Sep- 

 tember 1971, a school of approximately 35 spinner 

 dolphins was noted in shallow water at the edge of 

 the channel inside of Eastern Island. The regular 

 daytime occurrence of animals in the shallow atoll 

 lagoon was reported to us by residents of Midway. 



French Frigate Shoals. On 12 September 

 1971, at 0830 h, 30 animals were noted just off 

 Shark Island, spinning and leaping. 



I60°W 



d. 



Nihau 



(C^ 



\ Oahu ^ 



Oahu I 



Molokai 



Lanai\^ ^AMaui j) 

 Kahoolawe 



ZO^N 



MoroReet | Wench Fngate Shools 



Tern Is /, ^  



innacle \ ' " , .m,\ 



, DisoppeorifiQ \z 



Figure 3. — Sightings of spinner dolphin schools by the authors (triangles) in the Hawaiian Island chain. 



825 



