. California fish and game. Fisheries -- California; Game and game-birds -- California; Fishes -- California; Animal Population Groups; Pêches; Gibier; Poissons. LIFE HISTORY OF THE SEVENGILL SHARK 103. FIGURE 1. Commercial shark fisherman bringing aboard a 242 cm tl sevengill. Photograph by author. Since many elasmobranch species including the sevengill shark are mobile and reach a relatively large size, life history studies have been difficult. Members of the Hexanchidae are ovoviviparous (Gilbert 1981), but further information on their reproductive biology is limited. Herald and Ripley (195
. California fish and game. Fisheries -- California; Game and game-birds -- California; Fishes -- California; Animal Population Groups; Pêches; Gibier; Poissons. LIFE HISTORY OF THE SEVENGILL SHARK 103. FIGURE 1. Commercial shark fisherman bringing aboard a 242 cm tl sevengill. Photograph by author. Since many elasmobranch species including the sevengill shark are mobile and reach a relatively large size, life history studies have been difficult. Members of the Hexanchidae are ovoviviparous (Gilbert 1981), but further information on their reproductive biology is limited. Herald and Ripley (1951) examined a number of sevengill sharks between 54 and 228 cm tl caught at shark derbies and reported that all sevengills examined were sexually immature. Herald (1961) estimated that sevengills reached maturity at a length of 306 cm tl. However, Herald (1968) revised this estimate after examination of a male ( cm tl) and female (264 cm tl) sevengill that were both mature. Information on the feeding habits of the sevengill shark is rather incomplete. Hart (1973) reported that the sevengill's diet included smaller sharks. Herald and Ripley (1951) examined a few sevengill shark stomachs and found them to be either empty or to contain only bait. The objectives of this research were to investigate the life history of the sevengill shark in two northern California bays; this includes reproductive biology, length-weight relationships, food habits, age determination techniques, color variation, parasites, and movement patterns along the California coast. MATERIALS AND METHODS Sevengill shark data were obtained from field samples and reference collections. Most sevengill data were obtained from field collections made in Humboldt Bay (Iat40°52' N) and San Francisco Bay (Iat37°42' N). Additional data were obtained from the California Academy of Sciences, Moss Landing. Please note that these images are extracted from scanned page images that may have been digitally enhanced for r
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Keywords: ., bookauthorcaliforniadeptoffishandgame, bookauthorcaliforniafish
