3 
SUMMARY OF THE NON-GRID MARINE 
MAMMAL OBSERVATIONS - EAC 38 
Observations and data recorded for marine mammals during the non- 
Grid part of Eastern Area Cruise 38 were possibly the most significant 
of all non-Grid observations. These observations are also pertinent 
to our understanding of some of the marine mammals of the Grid study 
area. Six species of cetaceans and three species of pinnipeds were re¬ 
corded. The following is an outline of these observations. 
Eight sightings of Dali Porpoise ( Phocoenoides dalli ) that totalled 
some 44 to 46 porpoise. Seven of the observed pods were of porpoise 
traveling. The other•sighting was of a group milling about the surface 
and diving, probably for food. 
Three to five gray whales were recorded One single whale was 
noted migrating north The other two whales were observed inside 
Pt. Conception probably nursing calves. Sea conditions and i he distance 
these whales were from the ship prevented us from determining the posi¬ 
tive presence of the calves. 
Two schools of Common Dolphins ( Delphinus sp .) were observed in 
close proximity. One group of dolphins had solid dark dorsal fins- 
while animals in the other group had grayish patches in their dorsal 
fins. The dolphins of the latter school were aberrantly colored wil h 
a large patch of "white" posterior to the dorsal fin on both sides of 
the dorsal flanks. A third group of Delphinus was .noted mixed with 
Pacific Striped Dolphins ( Lagenorhynchus obliquidens ). This mixed group 
was also associated with a school of approximately 500 Northern Right- 
whale Dolphins ( Lissodelphis borealis ) and about 100 Risso Dolphins 
( Grampus griseusX Two specimens of Lissodelphis were killed but only 
one carcass was recovered. Blood samples and stomach contents were 
collected from the specimen. 
These four species were probably associated in the same area be¬ 
cause of one or more food species. Lissodelphis have not previously 
been recorded this far south ( 32 ° 15 '), bul based on what is known of 
its zoography one would expect to find Lissodelphis in this area. Both 
Grampus and Lissodelphis have been observed regularly in the eastern Grid 
and non-Grid areas. Many of these animals are probably the same ones 
we have seen on previous surveys The southern movements of these two 
species ( Lissodelphis and Grampus ) are probably related to hydrographic 
conditions which caused their food species to move south. These species 
do not utilize the same food species. Both of these dolphins probably 
range relatively little north or south of the area offshore of Pt. 
Conception. 
Shortly after the above group of dolphins was observed, a school of 
approximately 100 Lagenorhynchus was noted some distance from the ship. 
This species was also observed just out from Pt. Loma the day we ar¬ 
rived in San Diego. 
