CONTENTS 



Introduction 1 



Methods 2 



Sightings and abundance index trends by species 3 



Geographical distribution of fish school and school group sighting 3 



Apparent abundance index trends 3 



Northern anchovy 4 



Morro Bay to San Nicolas Island 4 



Pt. Hueneme to San Diego 4 



Index trends 4 



Pacific sardine 4 



Mono Bay to San Nicolas Island 4 



Pt. Hueneme to San Diego 5 



Index trends 5 



Pacific bonito 5 



Monro Bay to San Nicolas Island 5 



Pt. Hueneme to San Diego 5 



Index trends 5 



Pacific mackerel 5 



Morro Bay to San Nicolas Island 5 



Pt. Heneme to San Diego 5 



Index trends 10 



Jack mackerel 10 



Morro Bay to San Nicolas Island 10 



Pt. Hueneme to San Diego 10 



Index trends 11 



Tunas 11 



Bluefin tuna 11 



Index trends 12 



Albacore tuna 12 



Other sightings 12 



Yellowtail 12 



Pacific barracuda 12 



White seabass 12 



Basking shark 12 



Squid 12 



Discussion 12 



Evaluation of index data 12 



Sighting 12 



Identification 12 



School size estimation 12 



Comparison of apparent abundance measuring techniques 13 



Pacific mackerel 13 



Northern anchovy 13 



Pacific bonito 14 



Summary 14 



Acknowledgments 14 



Literature cited 14 



Figures 



1 . Block areas from near Half Moon Bay, Calif. , to Cedros Island, Baja California, Mexico, grouped in zones A to T as used in 

 this study 16 



2. Summary of observation effort, 1962-78. in terms of total day, night, and total overflights of block areas 17 



3. Graphic description of positioning the center of sighting 17 



4. Northern anchovy— location of centers of sighting for school or school groups, Morro Bay to San Nicolas Island, 1962-65 . . 18 



5. Northern anchovy— location of centers of sighting for school or school groups, Morro Bay to San Nicolas Island. 1966-79 . .19 



6. Northern anchovy— location of centers of sighting for school or school groups. Morro Bay to San Nicolas Island, 1970-73 . .20 



7. Northern anchovy— location of centers of sighting for school or school groups, Morro Bay to San Nicolas Island, 1974-78 . .21 



8. Northern anchovy— location of centers of sighting for school or school groups. Pt. Hueneme to San Diego. 1962-65 22 



9. Northern anchovy— location of centers of sighting for school or school groups. Pt. Hueneme to San Diego, 1966-69 23 



