CONTENTS 



Page 



Introduction 1 



Material and methods 2 



Chronological account of tagging operations, 1969-76 3 



Account of radiotagging experiment 6 



Results and discussion 8 



Short-term movements 8 



Long-term movements 8 



Acknowledgments 14 



Literature cited 14 



Figures 



1. Number of releases of tagged spotted dolphins, Stenella attenuata, by 2-degree area, 1969-76 2 



2. Number of releases of tagged spinner dolphins, Stenella longirostris, by 2-degree area, 1969-76 3 



3. Chute system used for tagging dolphins in the tuna seine 7 



4. Cruise track of chartered purse seiner Queen Mary while tracking movement of school of radiotagged 

 spotted dolphins, Stenella attenuata, in November-December 1971 8 



5. (Top) Minimum distance and net direction of travel, with days at liberty, of spotted dolphins, 

 Stenella attenuata, tagged 1969-76 and recaptured before 1 January 1977. Returns from radio trans- 

 mitters not included. (Bottom) Blow up of inset 11 



6. Minimum distance and net direction of travel, with days at liberty, of spinner dolphins, Stenella 

 longirostris, tagged 1969-76 and recaptured before 1 January 1977 11 



7. Movement of tagged spotted dolphins, Stenella attenuata, recaptured within 48 h of release 12 



8. Plot of minimum distance traveled on time at liberty (logarithmic scale) for tagged and recaptured 

 spotted dolphins, Stenella attenuata 13 



9. Deviation from E- W direction of net movement plotted on minimum distance traveled for tagged and 

 recaptured spotted dolphins, Stenella attenuata 13 



Tables 



1. Dolphins and small whales tagged, 1969-76. Radiotags included 2 



2. Tags released from commercial seiners, 1969-76 4 



3. Tag releases (steel-dart spaghetti tags) by NMFS observers aboard commercial tuna seiners, 

 1971-75 4 



4. Tag return data for spotted dolphin, Stenella attenuata, 1969-76. Recovered radiotags included 9 



5. Tag return data for spinner dolphin, Stenella longirostris, 1969-76 10 



6. Net distance traveled and net travel rates for radiotrack segments <50 h long 10 



7. Estimated catch of yellowfin tuna within 250 n.mi. and within 250-600 n.mi. of point of tag release 

 for 12 tagged dolphins recovered between 50 and 200 days after release and traveling up to 582 mi 

 (average 174 mi) and 15 tagged dolphins recovered between 200 and 400 days after release and trav- 

 eling <223 mi (average 93 mi). Catches for the first group are between 50 days after release and before 

 recapture and for the second group between 200 days and recapture 12 



8. Time of year at liberty and net direction of movement for seven tagged spotted dolpins, Stenella 

 attenuata, traveling more than 300 n.mi. before recapture 12 



