Kyne & Simpfendorfer.. - Shark Specialist Group

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Ebert and Davis 2007). These are the only skates for which this has been observed. The big skate can carry 2–7 embryos per egg case, with an average of 3–4 (Hitz 1964). There have been several ageing studies of rajid species, and while some are unvalidated and others preliminary, late maturity has again been demonstrated for the skates. Du Buit (1977) estimated a maximum age of 50 years for Dipturus batis while longevity of at least 20 years has been confirmed for A. radiata from skates tagged off Newfoundland (Templeman 1984). Ageing and growth estimates follow the general trend that larger species are slower growing and longer-lived than the smaller, faster-growing species (Sulikowski et al. 2005b). Ebert (2005) estimated the number of reproductive years for several skate species by considering age at first maturity and maximum observed age. Estimates for deepwater rajid skates ranged from 13 reproductive years for D. batis and D. innominatus (from Du Buit 1977 and Francis et al. 2001, respectively), through 9 years for Leucoraja wallacei (from Walmsley-Hart et al. 1999), 6 years for L. naevus and D. pullopunctata (from Du Buit 1977 and Walmsley-Hart et al. 1999, respectively), to 4 years for Raja rhina and D. nasutus (from Zeiner and Wolf 1993 and Francis et al. 2001, respectively) and 1–3 years for R. binoculata (from Zeiner and Wolf 1993) (Ebert 2005). Considering some more recent publications (see Table 2.15) similar estimations would give 3–6 reproductive years for female Amblyraja georgiana (from Francis and Ó Maolagáin 2005), 7 years for D. chilensis (from Licandeo et al. 2006) and 4 years for L. naevus (from Gallagher et al. 2004). The age estimations of McFarlane and King (2006) give considerably more reproductive years for both R. binoculata (17 years) and R. rhina (19 years) than those calculated from Zeiner and Wolf (1993). Estimates of annual and lifetime fecundity of rajid skates are highly variable between species. Annual fecundity has been estimated as 140 egg cases for R. clavata (shelf species; Holden 1975), 90 for R. brachyura (shelf species; Holden et al. 1971) and L. naevus (Du Buit 1976), 60 for R. montagui (shelf species; Holden et al. 1971), and 10–20 for A. radiata (Berestovskii 1994). Ebert and Davis (2007) calculated that annual fecundity in R. binoculata may reach 1260 based on assuming an average of 3.5 embryos per egg case, and egg-laying rates of 360 egg cases per year in captivity (K. Lewand, pers. comm. in Ebert and Davis 2007). Ebert (2005) extrapolated the annual fecundity of R. clavata to calculate a lifetime fecundity of ~980 egg cases based on the ageing estimates of Ryland and Ajayi (1984). For R. montagui, Ebert (2005) estimated annual production to be
Table 2.14. Reproductive biology of the deepwater rajid skates. Species Location L max Maturity (L 50 ) Maturity %L max Ovarian fecundity Size at hatching (mm TL) Reference Amblyraja radiata Gulf of Maine, NW Atlantic ♀ 1005mm TL ♂ 1003mm TL 875mm TL 865mm TL 87 86 -- -- Sulikowski et al. (2006) Dipturus chilensis Chile, SE Pacific ♀ 1170mm TL ♂ 930mm TL 1060mm TL 860mm TL 91 92 -- -- Licandeo et al. (2006) Dipturus innominatus New Zealand, SW Pacific ♀ 1380mm PL ♂ 1180mm PL 1122mm PL 933mm PL 81 79 -- -- Francis et al. (2001) Dipturus laevis Georges Bank, NW Atlantic ♀ 1335mm TL ♂ 1320mm TL 1163mm TL 1079mm TL 87 82 -- 180-190* Gedamke et al. (2005); *Bigelow & Schroeder (1953) Dipturus nasutus New Zealand, SW Pacific ♀ 740mm PL ♂ 680mm PL 591mm PL 517mm PL 80 76 -- -- Francis et al. (2001) Dipturus polyommata Queensland, Australia, Western Central Pacific ♀ 366mm TL ♂ 343mm TL 321mm TL 300mm TL 88 88 9-34 (20) ~100-110 <strong>Kyne</strong> et al. (in prep.) Dipturus pullopunctata South Africa, SE Atlantic ♀ 747mm DW ♂ 696mm DW 681-700mm DW 641-660mm DW 91-94 92-95 -- -- Walmsley-Hart et al. (1999) Leucoraja naevus Irish Sea, NE Atlantic ♀ 700mm TL ♂ 710mm TL 562mm TL 569mm TL 80 80 -- -- Gallagher et al. (2004) Leucoraja wallacei South Africa, SE Atlantic ♀ 571mm DW ♂ 512mm DW 400mm DW 395mm DW 70 77 -- -- Walmsley-Hart et al. (1999) Raja binoculata British Columbia, Canada, NE Pacific ♀ 1246mm TL ♂ 1220mm TL 830mm TL 650mm TL 67 53 -- -- McFarlane & King (2006) Raja rhina British Columbia, Canada, NE Pacific ♀ 2039mm TL ♂ 1836mm TL 900mm TL 720mm TL 44 39 -- -- McFarlane & King (2006) 93
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 80 and 81: Gonzalez 2006). Daley et al. (2002)
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 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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