Biology of Skates Developments in Environmental Biology of Fishes 27
Total Page：16
File Type：pdf, Size：1020Kb
Biology of Skates Developments in Environmental Biology of Fishes 27 Series Editor DAVID L.G. NOAKES For further volumes: http://www.springer.com/series/5826 David A. Ebert · James A. Sulikowski Editors Biology of Skates 123 Editors: David A. Ebert James A. Sulikowski Moss Landing Marine Laboratories University of New England Pacific Shark Research Center Marine Science Center Moss Landing, CA 95039, USA 11 Hills Beach Rd. Biddeford ME 04005, USA [email protected] ISBN: 978-1-4020-9702-7 e-ISBN: 978-1-4020-9703-4 DOI: 10.1007/978-1-4020-9703-4 Library of Congress Control Number: 2008942792 © Springer Science+Business Media B.V. 2008 No part of this work may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, microfilming, recording or otherwise, without written permission from the Publisher, with the exception of any material supplied specifically for the purpose of being entered and executed on a computer system, for exclusive use by the purchaser of the work. Printed on acid-free paper Springer.com Contents Preface: Biology of skates by D.A. Ebert & J.A. Sulikowski . 1–4 Biodiversity and systematics of skates (Chondrichthyes: Rajiformes: Rajoidei) by D.A. Ebert & L.J.V. Compagno . 5–18 Southern African skate biodiversity and distribution by L.J.V. Compagno & D.A. Ebert . 19–39 Food habits of the sandpaper skate, Bathyraja kincaidii (Garman, 1908) off central California: seasonal variation in diet linked to oceanographic conditions by C.S. Rinewalt, D.A. Ebert & G.M. Cailliet . 41–57 Food habits of the longnose skate, Raja rhina (Jordan and Gilbert, 1880), in central California waters by H.J. Robinson, G.M. Cailliet & D.A. Ebert . 59–73 Dietary comparisons of six skate species (Rajidae) in south-eastern Australian waters by M.A. Treloar, L.J.B. Laurenson & J.D. Stevens . 75–90 Comparative feeding ecology of four sympatric skate species off central California, USA by J.J. Bizzarro, H.J. Robinson, C.S. Rinewalt & D.A. Ebert . 91–114 Standardized diet compositions and trophic levels of skates (Chondrichthyes: Rajiformes: Rajoidei) by D.A. Ebert & J.J. Bizzarro . 115–131 Normal embryonic development in the clearnose skate, Raja eglanteria, with experimental observations on artificial insemination by C.A. Luer, C.J. Walsh, A.B. Bodine & J.T. Wyffels . 133–149 Endocrinological investigation into the reproductive cycles of two sympatric skate species, Malacoraja senta and Amblyraja radiata, in the western Gulf of Maine by J. Kneebone, D.E. Ferguson, J.A. Sulikowski & P.C.W. Tsang . 151–159 Morphological variation in the electric organ of the little skate (Leucoraja erinacea) and its possible role in communication during courtship by J.M. Morson & J.F. Morrissey . 161–169 Reproductive biology of Rioraja agassizi from the coastal southwestern Atlantic ecosystem between northern Uruguay (34°S) and northern Argentina (42°S) by J.H. Colonello, M.L. García & C.A. Lasta . 171–178 Profiling plasma steroid hormones: a non-lethal approach for the study of skate reproductive biology and its potential use in conservation management by J.A. Sulikowski, W.B. Driggers III, G.W. Ingram Jr., J. Kneebone, D.E. Ferguson & P.C.W. Tsang . 179–186 Age and growth estimates for the smooth skate, Malacoraja senta, in the Gulf of Maine by L.J. Natanson, J.A. Sulikowski, J.R. Kneebone & P.C. Tsang . 187–202 Age, growth, maturity, and mortality of the Alaska skate, Bathyraja parmifera, in the eastern Bering Sea by M.E. Matta & D.R. Gunderson . 203–217 Age and growth of the roughtail skate Bathyraja trachura (Gilbert 1892) from the eastern North Pacific by C.D. Davis, G.M. Cailliet & D.A. Ebert . 219–230 Age and growth of big skate (Raja binoculata) and longnose skate (R. rhina) in the Gulf of Alaska by C.M. Gburski, S.K. Gaichas & D.K. Kimura . 231–243 Preface: Biology of skates David A. Ebert Æ James A. Sulikowski Originally published in the journal Environmental Biology of Fishes, Volume 80, Nos 2–3, 107–110. DOI 10.1007/s10641-007-9244-3 Ó Springer Science+Business Media B.V. 2007 Synopsis Skates have become a concern in growth. To the best of our knowledge this is the recent years due to the preponderance of these first dedicated book on the biology of skates. We elasmobranchs that are caught as bycatch or as a hope that readers will find this issue of interest directed fishery. This has raised concern because and that it helps encourage and stimulate future skates have life history characteristics that may research into these fascinating fishes. make them vulnerable to over-exploitation. It was due to this increasing awareness and concern Keywords Rajidae Á Symposium Á Life history about these batoids that prompted us to organize an international symposium on the ‘‘Biology of Skates have become a concern in recent years due Skates’’. The aims and goals of the symposium to the preponderance of these elasmobranchs to were to bring together an international group of be landed as part of a directed fishery or researchers to meet, discuss, perhaps develop indirectly as bycatch. This has raised concern collaborations, and present their most recent because skates, like other chondrichthyans, have findings. The symposium was held over two days, life history characteristics that make them vul- on 13–14 July, 2006, in conjunction with the 22nd nerable to over-exploitation. However, until annual meeting of the American Elasmobranch recently this ubiquitous batoid group has received Society in New Orleans, LA. A total of 31 authors little study relative to the charismatic shark-like from four countries contributed 16 papers that fishes that are the target of major fisheries appear in this special issue. The papers are worldwide. Furthermore, due to their demersal broadly arranged into four separate categories: life-style on soft bottom substrates skates are systematics and biogeography, diet and feeding especially vulnerable to trawl fisheries. Although, ecology, reproductive biology, and age and shark fisheries are now being scrutinized and managed more closely than ever, skates despite being one of the more common and visible & D. A. Ebert ( ) components of bycatch fisheries are generally still Pacific Shark Research Center, Moss Landing Marine Laboratories, 8272 Moss Landing Road, Moss overlooked. In Alaskan waters, for example, the Landing, CA 95039, USA biomass of skate discard has been estimated at e-mail: [email protected] over 25 million metric tons, while skate landings along the California coast have increased 10-fold J. A. Sulikowski Marine Science Center, University of New England, in the past 2 decades. It has been well 11 Hills Beach Road, Biddeford, ME 04005, USA documented that trawl fisheries in the North D.A. Ebert & J.A. Sulikowski (eds.), Biology of Skates. DOI: 10.1007/978-1-4020-9703-4_1 1 2 D.A. Ebert & J.A. Sulikowski (eds.) Atlantic have impacted the abundance, popula- meeting of the American Elasmobranch Society tion structure, and distribution of several skate in New Orleans, LA (Fig. 1). A total of 25 species, causing several to be given commercially speakers, representing nine countries, presented prohibited status. Given the increased awareness papers during the symposium proper with another and concern globally, researchers have begun to three papers and five posters presented during the pay closer attention to these enigmatic fishes and general and posters sessions, respectively. The have begun to study their biology with a new- presenters included a nice mix of established found sense of urgency. professionals (n = 12) and young budding It was due this increasing awareness and researchers (n = 13), about 10 of whom were concern about these fishes that prompted us to presenting results from their masters theses or organize an international symposium on the Ph.D. dissertations. ‘‘Biology of Skates’’. The aims and goals of the A total of 31 authors from four countries symposium were to bring together an interna- contributed 16 papers that appear in this special tional group of researchers to meet, discuss, issue. The papers are broadly arranged into the perhaps develop collaborations, and present their same four separate categories as the symposium: most recent findings. The symposium was broadly systematics and biogeography, diet and feeding organized around four areas of research, system- ecology, reproductive biology, and age and atics and biogeography, diet and feeding ecology, growth. The first paper by David Ebert and reproductive biology, and age and growth aspects Leonard Compagno presents a historical perspec- of their biology. Our initial inquiry to gauge the tive on skate systematics over the past 250 years, interest of such a symposium was very well chronologically detailing the exponential growth received as approximately 75 researchers from in skate diversity, e.g. number of species and nearly 20 countries responded positively. The genera, and how a few individual researchers over overwhelming response we received confirmed the past 60 years have largely been responsible our belief that there was a high level of interest, for this dynamic increase in skate numbers. and concern, for skates. Included in this paper, in an appendix, is a The symposium was held over 2 days, on 13–14 checklist of all living skate species. Leonard July 2006, in conjunction with the 22nd annual Compagno and David Ebert then present a Fig. 1 Participants at the Biology of Skates symposium cis, Carl Luer, Joe Bizzarro, Michelle Treloar, Dana held in conjunction with the 22nd Annual American Bethea, David Ebert, Beth Matta, James Sulikowski, Chris Elasmobranch Society meeting in New Orleans, 13–14 Gburski, Duane Stevenson, Jim Ellis, Jorge Colonello, July, 2006. From left to right; Jeff Kneebone, Romney Daniel Figueroa, Dave Kulka, Jason Morson.