Summary of Pacific sleeper sharks, Somniosus pacificus Bigelow and Schroeder, 1944

.

Photo/ID Date Location Sex TL (m) M (kg)
CF
PCL (m) Comments and Reference
In Mass column, CF = Condition factor M/TL^3
        ~0.4?     FAO species cataloogue. Compagno (1984).
Size at birth? Adult females with up to 300 large eggs have been occasionaly taken.
NMNZ P14754 17 Oct 1983 Challenger Plateau
(41 16' S
169 05' E)
M 0.417   77.0 %TL Francis, Stevens, and Last (1988). New records of Smniosus (Elasmobranchii: Squalidae) from Australasia, with comments on the taxonomy of the genus. New Zealand Journal of Marined and Freshwater Research 22, 401-409.
Bottom trawl 938-941 m.
Neonate with an oval, unhealed 15 mm long yolk-sac scar between the gill slits.
Captive specimen 01 Dec 1988 Monterey Bay CA   0.656     Collected at 600 m with mid-water trawl where bottom depth ~ 1000 m by Monterey Bay Aquarium. Died 09 Dec 1988. In captivity for 8 days.
LACM 37706-1   25 m WNW of San Nicholass Island CA F 0.740     Ebert, Compagno, and Natanson (1987)
Taken at depth of 1300 m
MLML 4   Monterey Bay CA F 0.740     Ebert, Compagno, and Natanson (1987). Biolgical notes on the pacific sleeper shark, Somniosus padificus (Chondrichthyes: Squalidae). California Fish and Game 73, 117-123.
Captured by trawler in Monterey Bay at depth of 390 m.
Had 1 mm long yolk-sac scar. Tooth counts: upper 17-0-16, lower 27-0-28.
CAS 38917     F 0.877     Ebert, Compagno, and Natanson (1987).
Tooth counts: upper 16-0-16, lower 28-0-26.
CDFG uncat.     F 0.928     Ebert, Compagno, and Natanson (1987).
Tooth counts: upper 10-0-12, lower 29-0-27.
LJVC-0405     F 1.060   80.2 %TL Ebert, Compagno, and Natanson (1987).
Tooth counts: upper 21-0-20, lower 30-0-28.
NMNZ P20297 10 Nov 1986 Pukaki Rise (49 10' S,
171 16' E)
M 1.215   82.5 %TL Francis, Stevens, and Last (1988).
Bottom trawl 405-410 m.
CSIRO H490 2 Apr 1986 South Tasman Rise
(46 59' S
148 06' E)
F 1.368   83.3 %TL Francis, Stevens, and Last (1988).
Bottom trawl 1020-1070 m.
CAS 27084     F 1.140     Ebert, Compagno, and Natanson (1987).
Tooth counts: upper 16-0-17, lower 28-0-25.
Captive specimen 25 May 1999 Set-net at minami-Kayabe, 30 km NE of Hakodate, Hokkaido M 1.74 52.0
(9.9)
  Dr. Kazuhiro Nakaya posting to elasmo-l on June 7, 1999. Was kept at nearby Usujiri Maine Laboratory until June 7, 1999 (14 days) and was feeding. Was moved to Otaru Aquarium on June 7, 1999.
(Two individuals were caught in a year. First one was immediately transported to Ataru Aquarium, but died in a week or so. Second one was kept for 2 weeks or so in the tank of our field station, and ate salmon and other things. However, as I could not take care of the shark, I sent it to Otaru Aquarium again. There, they kept it for a while, but they released it, because it became weak.Dr. Kazuhiro Nakaya personal communication.)
  Mar-May 2002 Ching-Shuei Cliffs, Eastern Taiwan   1.99 60
(7.6)
  Wang and Yang (2004). First records of pacific sleeper sharks (Somniosus pacificus Bigelow and Schroeder, 1944) in the subtropical waters od Eastern Taiwan. Bulletin of Marine Science 74, 229-235.
LJVC-0418       2.113   78.6 %TL Ebert, Compagno, and Natanson (1987).
SCY-02-16 Mar-May 2002 Ching-Shuei Cliffs, Eastern Taiwan   3.40 470
(12.0)
  Wang and Yang (2004).
Images/RA_sleeper_shark11.jpg last week in Sep 2006 South of Morro Bay, CA USA   ~3.5     Thanks to Keri York: We were south of Morro Bay towing in ~100 fathoms deep and caught a large sleeper shark. We released it hoping that it would live. It was regurgitating hake, large chunks of meat that looked like the texture of squid, and squid beaks, which I saved. I am attaching a couple of pictures.
CAS 27082     F 3.66     Gotshall and Jow (1965) according to Ebert, Compagno, and Natanson (1987).
Contained 300 unfertilized, ovarian eggs raanging fro 45-58 mm in diameter.
Tooth count: lower jaw 26-0-27.
      F 3.7     Adult female. FAO species cataloogue. Compagno (1984).
  Mar-May 2002 Ching-Shuei Cliffs, Eastern Taiwan M 3.85 586
(10.3)
  Wang and Yang (2004). Claspers of this male were rigid and calcified, indicating maturity.
LJVC-0482       4.01 >888
(>13.8)
  Ebert, Compagno, and Natanson (1987).
Contained ~ 400 large yellow vascularized ovarian eggs. 372 could be collected, 20-30 were lost during dissection. 324 ranged from 24-50 mm in diamter. 48 were broken and could not be measured.Tooth counts: upper 25-0-23, lower 31-0-29.
        4.08     Ebert, Compagno, and Natanson (1987).
Contained no eggs.
  Mar-May 2002 Ching-Shuei Cliffs, Eastern Taiwan F 4.15 824
(11.5)
  Wang and Yang (2004).
  Mar-May 2002 Ching-Shuei Cliffs, Eastern Taiwan F 4.18 674
(9.2)
  Wang and Yang (2004). This female had 200-300 small, white, semi-transparent ova of ~ 1 cm diameter in the ovary.
CDFG uncat     F 4.19     Ebert, Compagno, and Natanson (1987).
Contained no eggs.Tooth counts: upper 18-0-18, lower 27-0-27.
CAS-33586     F 4.30 545.5
(6.9)
80.9 %TL Ebert, Compagno, and Natanson (1987).
Had only one large egg in the uterus and may have lost others while being lifted from the water
  Mar-May 2002 Ching-Shuei Cliffs, Eastern Taiwan   4.56 OTC     There was also one shark that was measured at 456 cm (unfortunately, it was measured along the curve of the body due to its bent position). John Y. Wang pers. comm.
      F 7     FAO species cataloogue. Compagno (1984). Largest female captured and measured was 4.3 m TL but larger individuals estimated at 7 m TL or more have been photographed in deep water.
Photo/ID Date Location Sex TL (m) M (kg)
CF
PCL (m) Comments and Reference
In Mass column, CF = Condition factor M/TL^3

Created May 2005; updated October 2006. Back to previous page
Please send comments or corrections to henry@elasmollet.org