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NORSK HVALFANGST-TIDENDE Nr. 3 Observations of Odontocetes in Central Californian Waters *) **) by ROBERT L. BROWNELL, Jr.

Introduction. City>>on the afternoon of June 16, 1963 and con- sisted of approximately twelve . From this This reports observations of odontocetes made group a 11.0 m (36 ft) male was harpooned at a during the summer of 1963 in central Californian location of 36' 10'N-12J010'W. At this time the waters. I made my observatilons aboard catcher whales were heading south. This is the southern- boats of the Golden Gate Fishing Company, Point most recorded account of this species. The tem- San Pablo, California. perature was 12.2 C. Information was obtained on eight different spe- On July 7, 1963 the third sighting was recorded cies. These are: bairdi Stejneger, Delphi- by the author aboard the whaler >.The nus bairdi Dall, Lissodelphis borealis (Peale) , La- locality of this sight was about 30 miles southwest genorhynchus obliquidens Gill, Orcinus orca (Lin- offshore from Point Reyes. Initially this group was naeus) , Globicephala scammoni Cope, observed by the splashing they produced in the vomerina Gill, and Phocoenoides dalli (True). water. The discussion of these species follows the ar- When the boat approached these whales lay al- rangement of Miller and Kellogg, 1955. The ranges most stationary at the surface of the water in a are listed if not mentioned in or if different from discoid pattern. The movements of the individual Norris and Prescott, 1961. in this group varied. They were doing one The season referred to in this report of three things: (1) <(Standing>bolt upright in the opened on April 16, 1963 and closed on October 15, water with 6 to 8 feet of their bodies above the sur- 1963 for baleen whales. face. As in Pacific pilot whales this occurred as we All locations listed in this report can be found on approached. (2) ((Standing, inverted in the water Figure 1. with 6 or 7 feet of their tail extended above the sur- face. The position was held for several seconds be- BAIRD'S BEAKED WHUE (Berardius bairdij fore the flukes fell back into the water. (3) Slowly swimming or floating at the surface of the water. Range. - Berardius bairdi occurs in the eastern This schooling type in Pacific pilot whales (Globi- north Pacific from the , St. Matthew cephala scammni) has been called the Loafing Islands (Hanna, 1920) and ranges south to Cali- group by Norris (1958). Masaharu Nishiwaki (per- fornia, Santa Cruz and Monterey Bay (Davidson, sonal communication 1963) has also observed this 1929). This report extends the range south to same sort of behavior in Baird's beaked whales in 36'10'N. Japanese waters. Abundance. - Each usually one or more The fourth recorded sighting occurred aboard Baird's beaked whales are taken by the catcher >, on September 7,1963. Approximate- boats. These whales are prevalent throughout most ly three animals were observed by Frank W Maurer, of the whaling season, but they are very seldom Jr., Fish and Wildlife Service Biological Aid, at taken because their relative small size makes them 36"52'N-122"417W. economically unattractive. Observations. - Two Baird's (beaked whales were taken during the 1963 whaling season. The first was PACIFIC COMMON (Delphinus bairdz j encountered and taken on May 24, 1963. This was captured by the catcher

- -i PI REYES

FARALLON * ISLANDS '

A~ONUEVO 2 1CRUZ

REY BAY

36

122" F~guse1. - Chart of the whaling grounds in Central Cahfornian waters. chus obliquidens). This observation was made on feeding on anchovies (Engraulis mordax). As we June 26, 1963. At this time our position was approached the larger whales a mixed group of 37'18'N-123"16'W. about fifty dolphins and between seventy-five to one-hundred Pacific striped dolphins NORTHERN ( obliquidens) was sighted. This (Cissodelphis borealis) school of black slender animals, lacking dorsal fins, was composed of two compact subgroups of about Observations. - On July 14, 1963 at 37'43'N- twenty-five animals each. As the animals swam 123'40'W the >encountered a mixed they leaped in unison out of the water in a series group of baleen whales. These whales, six adult sei of regular low-angle leaps. Unlike Lagenorhynchus, whales ( borealis) and two juvenile Delphinus, and Phocoenoides, the right whale dol- humpback whales (Megaptera novaeangliae), were phins did not attempt to ride our vessel's bow. NORSK HVALFANGST-TIDENDE PACIFIC water about twelve times in rapid succession then (Lagenorhynchz~sobliquidens) rested for approximately one minute and then start- ed leaping again. Another Pacific striped dolphin Abundance. - Brown and Norris (1956) reported threw its flukes and slapped the surface just before that this dolphin was common in the inshore waters submerging. The behavior of these two juvenile of Southern California during winter and spring dolphins occurred in front of the humpback months, and that it moved offshore in summer and whales. The other dolphins and swam on fall. In central Californian waters this species is either side of the baleen whales. found offshore during the summer. The offshore population movement appears to be 'elated to the (Orcinus orca) movement of anchovies (Engraulis mordax). Almost every time that anch'ovies were sighted Pacific Abundance. - During the whaling season killer striped dolphins were found feeding on them. This whales occur frequently from time to time in is the most abundant cetacean found during the waters off central California. These are not usually summer in central Californian waters. taken commercially due to their small size. Observations. - Table 1 lists some of the records Observations. - The first sighting of killer of this dolphin, Many more sightings were made whales was made aboard the on June than are reported in this paper. These could not be 25, 1963 about 8:30 P.M. We were coming in toward recorded due to the requirement of work aboard Afio Nuevo Island to anchor for the night. A group the boat. of twelve to fifteen males was observed swimming Table 1. towards shore about 6% miles offshore at the 50 Pacific Striped Dolphin Observations. fathom line. Date Locakty No. of animals The second sight and only catch of a killer whale 24 June 1963 37"30'N-123" 15'W 25- 30 26June1963 37"18'N-123'16'W 60- 75 occurred on July 1, 1963. This 7.2 m (24 ft) male 28 June 1963 37'10'N-123'14'W 25- 30 was taken by the >.When harpooned this 4 July 1963 37'42'N-123"43'W 15 was alone, swimming in about 40 fathoms 5 July 1963 37"41'N-123"13'W 12 of water about 2 '/2 miles off Point Reyes. 14 July 1963 37"43'N-123'40'W 75--100 9 Au~.1963 37'40'N-123"lO'W 15- 20 PACIFIC (Globicephala scammoni)

Social behavior. - In pursuing baleen whales Abundance. - Pacifiic pilot whales are not com- (Balaenoptera and Megaptera) we used Pacific monly sighted within the whaling grounds off striped dolphins to keep track of them. It was com- central California. Each whaling season only two mon to see Pacific striped dolphins following the or three schools are sighted on the whaling grounds. fleeing baleen whales. The dolphins would reveal Observations. - One small school of Pacific pilot their position because they had to breathe at short- whales was sighted in the region around the Faral- er intervals than the larger cetaceans. Ion Islands. This group was spotted on August 9, On July 4, 1963, we shot and instantly killed a 1963 and contained adults and several juveniles. 13.2 m (43 ft) (Balaenoptera borealis). There were approximately twelve whales in the Our position was 37'42'N-123'45'W. This whale school. Our location was 37'31'N-123'56'W. was accompanied by about fifteen Pacific striped dolphins and three Dall porpoises (Phocoenoides HARBOR (Phocoena vomerina) dalli). When the whale was shot the smaller ani- mals followed it as it sank, diving to the carcass re- Abundance. - Harbor porpoises are sighted com- peatedly until it had been pulled again to the sur- monly in the area just offshore from the Golden face. The usual behavior of these species is to flee Gate bridge. the area immediately. This type of ;behavior where Scammon (1874) reports this species occasionally the dolphins and porpoises stayed near the baleen taken in the seines by fishermen along the shores whale was observed only once. of San Francisco Bay. Today this animal is not com- mon in San Francisco Bay. This is probably due to Twelve Pacific striped dolphins and several Dall water pollution and boat traffic. porpoises were observed with three juvenile hump- Observations. - Only two harbor porpoises were back whales on July 5, 1963. This assemblage was observed, both near the San Francisco Bay en- first sighted when the humpback whales were trance. The first sighted on July 19, 1963 about % breaching as they surfaced. As the >ap- of a mile north of the No. 1 channel buoy leading proached they started swimming in a normal man- into the bay. The sea temperature was 13.3 C. The ner. At this time one of the Pacific striped dolphins second harbor porpoise was observed inside the San started breaching. The animal jumped clear of the Francisco lightship about three miles. The porpoise NORSK HVALFANGST-TIDENDE

Figure 2. - Calor patterns observed in tihe dvrsail sins of Dall Porpoises. was seen on August 9, 1963. On that day the water Although morphologic data from these and other temperature was 14.9 C. observations will be the subject of further publica- tion I want to mention the remarka~blevariations in the color patterns of the of these ani- DALL PORPOISE (Phocoenoides dalli) mals. One individual was observed with a totally black dorsal fin. This has also been reported by Brown and Norris (1956). Figure 2 shows some of Abundance. - In central Californian waters the color patterns of the dorsal fin. Phocoenoides dalli is the species sighted most dur- ing the summer months. In the winter these move Behavior. - Like Norris-Prescott (1961) I feel into Southern Californian waters. that Dall's porpoise is the swiftest of the small del- Observatwns. - During the summer of 1963 while phineds occurring in both central and Southern aboard the whaling boats this species was seen al- Californian waters. most every day at sea. The Dall porpoise on all oc- These porpoises maneuver &out the ship's bow casions except once was observed outside the 50 with extraordinary bursts of speed. One moment fathoms curve. Table 2 lists the recorded sighting they will be riding the ;bow then the next they will and water temperatures for the Dall porpoises. veer off and move with an incredible speed away from the ship.

Table 2. DaEl Porpoise Observations and Sea Temperatures.

No. of Date Localllity anfimalfs Etablert 1885 24 June 1963 37'36'N-123"14'W 3 Siv.ing. Th. Jespersen 25 June1963 37"39'N-123" 1'W 4 Siv.ing. Karsten B. Halvorsen 27 June1963 37" 13'N-122O46'W 4 Siv.ing. Helge P. Halvorsen 28 June1963 37" 4'N-123O17'W 3 28 June 1963 37" 5'N-123" l7'W 10-12 Medlemmer av 4 July 1963 37'42'N-123"45'W 3 Norske Patentingenimers Forening 13 July 1963 37"38'N-122"57'W 2040 14 July 1963 37'45'N-122"44'W 3 Karl Johans gt. 41 - Oslo 1 9 Aug. 1963 37" 1'N-123' 9'W 3 Telefoner 41 43 09 - 33 70 02 9 Aug. 1963 37"39'N-123"18'W 2 Telegramadr.: ~~Nesroht~ 10 Aug. 1963 37"46'N--123"lO'W 12 59 66 NORSK HVALFANGST-TIDENDE Nr. 3 Acknowledgments. Davidson, M. E M, 1929 Bamd's at Santa Cruz, Californtia Jour Mamm , lQ(4) 356-356 I wish to thank Robert Casebeer and Herman Guiguet, C. 3, 1965 A record of Bawd's dolphin (Delphznzus Foland who made it possible for me to work aboard bawd% DaLI) an Brrtish Co!lumbua. Canadian Field-Nat., their boats; catcher boat captains Loyd Newton 68(4) 1'36 ~Lynnanmand Harold Ridle <

A Pygmy at Durban By RAY GAMBELL, Whale Research Unit, National Institute of Oceanography, c/o Britlsh Museum (Natural History)

On the 21st September 1963, while I was carrying rather light body colour, absence of any external out biol~ogicalinvestigations on whales for the Na- parasites, and a few oval scars which were just tional Institute of Oceanography at the shore sta- healed over, or had healed recently. No vaginal tion of The Union Whaling Company Ltd., Durban, band or tag was present, and there was no evidence , a female Blue whale was brought up of disease or deformity which might have inhibited onto the platform. It had been killed on the position normal growth. 30°30'S, 31'28' E, and immediately attracted atten- tion on the platform. Although its length was re- Baleen. corded as only 66 feet, some 11 feet less than the average length at which ordinary female Blue A plate from the middle of the baleen row was whales become sexually mature (Mackintosh 1942), collected, and its proportions support the identifica- foetal membranes were protruding from the vulva. tion of the whale. The actual dimensions of the Further investigation has confirmed that it was a baleen plate are length 55.3 cm. and breadth 42.8 Pygmy Blue whale, and a brief description of some cm., measured in the way described !by Ichihara features of the whale are given here, since this ap (1961). The ratio of length to breadth is then 1.29, pears to be the first record of this species at Dur- well within the range of this ratio for Pygmy Blue ban. whales (1.06---1.90), but at the extreme limit of the values for the ordinary Blue whale (1.25-2.34) External Characters. shown by Ichihara (1963). The baleen of this Durban specimen was very The only external characters noted were the heavily infested with Balaenophilus unisetus both