Kyne & Simpfendorfer.. - Shark Specialist Group

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Gonzalez 2006). Daley et al. (2002) suggests that D. licha has a non-continuous reproductive cycle. Order Squatiniformes. Angelsharks. Family Squatinidae. Angelsharks. The angelsharks included in this report are all marginal deepwater species that occur on the shelf and upper slope. The deepest recorded is 500m for the sawback angelshark Squatina aculeata from the Atlantic and 494m for the African angelshark S. africana. Of the species included here two Australian endemics remain undescribed (Last and Stevens 1994) and are relatively poorly-known, as is S. africana and the Taiwan angelshark S. formosa. Reproductive parameters for the remaining outer shelf and upper slope squatinid sharks are summarized in Table 2.9. Squatinids are yolk-sac viviparous (Musick and Ellis 2005) and their reproductive potential is limited. All have small litter sizes and extended gestation periods with possible biennial reproductive cycles in at least some species. Litter sizes in the upper slope species range from 2 to 12 and Bridge et al. (1998) suggested that gestation in S. tergocellata lasts 6–12 months with a probable biennial reproductive cycle, while Capapé et al. (2005) provided evidence for a ~12 month gestation in S. aculeata. A female breeding cycle of at least 2 years has been suggested for S. argentina (Vooren and Klippel 2005). Table 2.9. Reproductive biology of outer shelf and upper slope squatinid sharks. A litter size value in parentheses is the mean value. Species Location TL max (mm) Maturity (mm TL) Maturity %TL max Litter size Size at birth (mm TL) Reference Squatina aculeata Senegal, EC Atlantic and Tunisia, Mediterranean ♀ 1750 ♂ 1520 1370-1430 1200-1220 78-82 79-80 8-12 (11.1) 303-350 Capapé et al. (2005) Squatina argentina Southern Brazil, SW Atlantic ♀ 1380 ♂ -- ~1200 ~1200 87 -- 7-11 -- Vooren & Klippel (2005) Squatina tergocellata Southern Australia, Eastern Indian ♀ 1400 ♂ 1025 1150-1250 810-910 82-89 79-89 2-9 (4.5) ~325-415 Bridge et al. (1998) Order Pristiophoriformes. Sawsharks. Family Pristiophoridae. Sawsharks. The deepwater sawsharks are poorly-known, with several species remaining undescribed. All species have relatively restricted distributions. Sawsharks are yolk-sac viviparous and Bass et al. (1975) reported a litter of seven embryos in a sixgill sawshark Pliotrema warreni, but noted that the female had apparently aborted several other embryos upon capture. Ovarian fecundity from a larger number of females was 7–17 (average 12.5) (Bass et al. 1975). Maturity is reached in females by ~1100mm TL and in males by ~830mm TL, representing 81% and 74% of TL max reported by Bass et al. (1975), respectively. The species is more common on the shelf in some parts of its distribution (including possible shallower water 80
pupping grounds), but occurs more regularly in deeper water in other areas (Compagno in prep. a). Data from southern Australian shelf Pristiophorus species (P. cirratus and P. nudipinnis) indicate litter sizes of 6–19 pups produced every other year (biennial reproductive cycle) (Compagno et al. 2005). The biology of the truly deepwater Bahamas sawshark Pristiophorus schroederi, along with undescribed Pristiophorus species from the Indo-West Pacific, however, is essentially unknown (Compagno in prep. a). Order Heterodontiformes. Bullhead Sharks. Family Heterodontidae. Bullhead Sharks. The whitespotted bullhead shark Heterodontus ramalheira is unique amongst the family in having a preference for deeper waters than its congeners, which are generally shallow inner shelf species (Compagno 2001). Bullhead sharks are oviparous, but there is no information on the biology of this rare species (Compagno 2001). Order Orectolobiformes. Carpetsharks. Family Parascylliidae. Collared Carpetsharks. The two deepwater species of the small shark family Parascylliidae are very poorly-known. Both are rare restricted range endemics known from narrow depth ranges on the upper slope. These species are oviparous but there are no other details on their biology (Compagno 2001). The ginger carpetshark Parascyllium sparsimaculatum is known only from three female specimens (Last and Stevens 1994, Goto and Last 2002). Order Lamniformes. Mackerel Sharks. Family Odontaspididae. Sand Tiger Sharks. Sand tiger sharks are oophagous, and although litter sizes have not been documented in either of the deepwater species, the smalltooth sand tiger Odontaspis ferox or the bigeye sand tiger O. noronhai, they are likely two, given the mode of reproduction and data from the inshore sand tiger shark Carcharias taurus. This latter species displays a modified form of oophagy whereby the largest embryo in each uterus consumes its sibling embryos before relying on ova ovulated by the mother (Musick and Ellis 2005). This form of oophagy is termed adelphophagy or uterine cannibalism and has only been confirmed for C. taurus (Musick and Ellis 2005). The reproductive productivity of C. taurus is low (2 pups every other year) (Compagno 2001, Lucifora et al. 2002) and it is likely that productivity in the deepwater odontaspidids is similarly restricted. Fergusson et al. (in press) report that nowhere in its wide but scattered distribution is O. ferox abundant. They report maturity in females at ~3000–3500mm TL (73–85% TL max ) and in males ~2000–2500mm TL (58–73% TL max ), and suggest a size at birth of ~1000mm TL. There are no particular details available concerning the biology of O. noronhai, although Compagno (2001) suggests maturity in females at ~3200–3250mm TL. Family Pseudocarchariidae. Crocodile Sharks. Despite its widespread distribution, locally common occurrence in some regions and its regular bycatch in pelagic longline fisheries, the biology of the crocodile shark Pseudocarcharias kamoharai has not been examined in detail. Most information has come from the incidental capture of gravid females. As with other lamnoid sharks, it is oophagous 81
Page 1 and 2:
A COLLATION AND SUMMARIZATION OF AV
Page 3 and 4:
TABLE OF CONTENTS Executive Summary
Page 5 and 6:
Reproductive output in deepwater ch
Page 7 and 8:
GENERAL INTRODUCTION THE CLASS CHON
Page 9 and 10:
Leucoraja circularis, blonde skate
Page 11 and 12:
SECTION I. BIODIVERSITY AND AN ANNO
Page 13 and 14:
Table 1.1. The diversity of deepwat
Page 15 and 16:
ANNOTATED CHECKLIST OF EXTANT DEEPW
Page 17 and 18:
Habitat zones broadly follow Compag
Page 19 and 20:
Chimaera lignaria Didier, 2002. Gia
Page 21 and 22:
Hydrolagus trolli Didier & Séret,
Page 23 and 24:
Squalus melanurus Fourmanoir, 1979.
Page 25 and 26:
Deania hystricosum (Garman, 1906).
Page 27 and 28:
Etmopterus molleri (Whitley, 1939).
Page 29 and 30: Scymnodalatias sherwoodi (Archey, 1
Page 31 and 32: Squatina formosa Shen & Ting, 1972.
Page 33 and 34: Torpedo nobiliana Bonaparte, 1835.
Page 35 and 36: Bathyraja matsubarai (Ishiyama, 195
Page 37 and 38: Brochiraja spinifera (Garrick & Pau
Page 39 and 40: Amblyraja hyperborea (Collette, 187
Page 41 and 42: Dipturus mennii Gomes & Paragó, 20
Page 43 and 44: Fenestraja cubensis (Bigelow & Schr
Page 45 and 46: Okamejei sp. N [Last & Stevens, 199
Page 47 and 48: Family Anacanthobatidae. Legskates.
Page 49 and 50: Family Dasyatidae. Whiptail Stingra
Page 51 and 52: Apristurus kampae Taylor, 1972. Lon
Page 53 and 54: Apristurus sp. [Séret]. Western Ce
Page 55 and 56: Western Central Atlantic: Straits o
Page 57 and 58: Pentanchus profundicolus Smith & Ra
Page 59 and 60: Mustelus canis insularis (Mitchell,
Page 61: Musick, J.A., Harbin, M.M. and Comp
Page 64 and 65: efore relying on ovulated ova) and
Page 66 and 67: FAMILY LIFE HISTORY ACCOUNTS PART 1
Page 68 and 69: Family Squalidae. Dogfish Sharks. T
Page 70 and 71: often related to maternal size, lar
Page 72 and 73: Table 2.3. Reproductive biology of
Page 74 and 75: 16 embryos (Table 2.5). Irvine (200
Page 76 and 77: Table 2.6. Age and growth of etmopt
Page 78 and 79: Table 2.7. Reproductive biology of
Page 82 and 83: and in the case of the crocodile sh
Page 84 and 85: Balart et al. (2000) is 295mm TL fo
Page 86 and 87: Table 2.11 (continued). Species Loc
Page 88 and 89: PART 2. BATOIDS Order Rajiformes. B
Page 90 and 91: years for females of all species ag
Page 92 and 93: Ebert and Davis 2007). These are th
Page 94 and 95: Table 2.15. Age and growth of rajid
Page 96 and 97: PART 3. HOLOCEPHALANS Order Chimaer
Page 98 and 99: SEGREGATION, MOVEMENT AND MIGRATION
Page 100 and 101: PRODUCTIVITY OF DEEPWATER CHONDRICH
Page 102 and 103: e slow to recover from overfishing.
Page 104 and 105: 0.16 0.14 Intrinsic rebound potenti
Page 106 and 107: Bigelow, H.B. and Schroeder, W.C. 1
Page 108 and 109: Conrath, C.L., Gelsleichter, J. and
Page 110 and 111: Squaliformes) in the southwestern e
Page 112 and 113: Hoenig, J.M. 1983. Empirical use of
Page 114 and 115: Lucifora, L.O., Valero, J.L. and Ga
Page 116 and 117: Parsons, G.R., Ingram, G.W. Jr. and
Page 118 and 119: Sulikowski, J.A., Elzey, S., Kneebo
Page 120 and 121: K. (eds.). Indo-Pacific Fish Biolog
Page 122 and 123: deepwater species categories for ea
Page 124 and 125: Table 3.1. FAO FIGIS database categ
Page 126 and 127: CASE STUDY 1. AUSTRALIAN SOUTHERN A
Page 128 and 129: Table 3.2. Mid-slope deepwater shar
Page 130 and 131:
CASE STUDY 2. NORTHEAST ATLANTIC DE
Page 132 and 133:
CASE STUDY 3. AZORES KITEFIN SHARK
Page 134 and 135:
CASE STUDY 4. MALDIVES GULPER SHARK
Page 136 and 137:
SECTION III LITERATURE Adam, M.S.,
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