Life history information on 28 sixgill sharks, collected off California, was obtained from May 1982 through Sept. 1984. Only one mature sixgill shark, a 421 cm TL female with term embryos, was ...examined. Size at maturity was estimated for females by comparing gonad development with length-weight measurements. Gut analysis revealed that the sixgill shark's diet consists mainly of bony and cartilaginous fishes. Since sixgill sharks do not appear to be abundant anywhere, their distribution and movement patterns along the deep coastal waters off California are, for the most part, unknown.
Geographic range extensions and confirmatory records of 12 spp are listed. The Pacific hagfish Eptatretus stoutii was captured off San Pablo Point, extending the range {approx} 148 km. A sixgill ...shark Hexanchus griseus was collected for the 1st time in Mexican waters in Todos Santos Bay. A ratfish Hydrolagus colliei was collected off Cedros Island, extending the range {approx} 389 km. Anchoa exigua was taken in Plays Maria Bay giving a 370 km extension. Physiculus rastrelliger was caught near the type locality, Anoplopoma fimbria off San Bentio Islands, Zaniolepis latipinnis off San Martin Island (222 km southward extension), Z. frenata off Turtle Bay (105 km southward extension), Agonopsis sterletus SE of San Martin Island (686 km southward extension), Epinephelus niveatus in San Cristiobal Bay, Parophrys vetulus in the San Cristobal Bay (93 km southward extension) and Microstomus pacificus in San Cristobal Bay (185 km southward extension).
A Canadian-made prototype manned submersible, deployed from the waterfront of Vancouver, British Columbia, Canada, was instrumental in the discovery of the presence of juvenile sixgill sharks, ...Hexanchus griseus, in 100-m depths. The relative ease of finding juveniles of this "urban shark" species close to the city of Vancouver in depths deeper than divers can penetrate or fishermen regularly fish reflects the presence in nearshore habitat for a species that is well known south of the US-Canada border in the large marine catchment area of the Salish Sea. The bluntnose sixgill shark is a large-bodied carnivorous shark typically found in deepwater (to 2,000-plus m) throughout the oceans and in certain shallow waters. The objective of the study was to determine the feasibility of using a three-man research submersible in conjunction with attractants at a location close to urban Vancouver as a census method for sixgill sharks that extends the search range for uncommon taxa beyond the depths normally encountered by divers and fishers.
PDF