DOCSLIB.ORG

Microchemical Analyses of Otoliths in Baltic Sea Fish

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Microchemical Analyses of Otoliths in Baltic Sea Fish Microchemical analyses of otoliths in Baltic Sea fish -Possibilities and limitations of otolith elemental analysis to describe individual life history and stock characteristics of fish in the Baltic Sea- Dissertation zur Erlangung des Doktorgrades der Mathematisch-Naturwissenschaftlichen Fakultät der Christian-Albrechts-Universität zu Kiel vorgelegt von Lasse Marohn Kiel, Juli 2011 Referent: PD Dr. Reinhold Hanel Korreferent: Prof. Dr. Carsten Schulz Tag der mündlichen Prüfung: 04.10.2011 Zum Druck genehmigt: Kiel, Der Dekan SUMMARY In this thesis otolith microchemistry analyses were used to gain insights into the individual life history and stock characteristics of three fish species from the Baltic Sea - the European eel Anguilla anguilla, the Atlantic cod Gadus morhua and the thicklip grey mullet Chelon labrosus. The special hydrographic environment of the world’s largest brackish water system provide promising conditions for the use of otolith elemental analysis to investigate individual migration patterns and stock structures of fish. Here, it was used to gain information with relevance for stock management of fish species that differ widely in their biology, ecology and stock structure. In chapter I the influence of continental migratory behaviour on health and spawner quality of the European eel was analysed. Otolith strontium (Sr) composition was used to identify characteristic migration patterns. Results show that the muscle fat contents of silver eels with strictly catadromous life cycles are significantly reduced compared to silver eels that never entered freshwaters. Furthermore, prevalence and infection intensities of the swimbladder nematode Anguillicoloides crassus are highly increased in catadromous silver eels. Both, a reduced accumulation of fat reserves and intense A. crassus infestations are assumed to impair the successful reproduction of A. anguilla. These results highlight the importance of brackish water habitats for the production of high quality spawners and question the benefit of restocking measures into inland waters. In order to investigate the influence of water temperature and feeding behaviour on the element incorporation into A. anguilla otoliths, two experimental studies were conducted (Chapter II & III). It was investigated whether experienced temperature history and individual food preferences can be reconstructed by otolith microchemistry analysis. It was further tested if temperature or diet affect the incorporation of Sr into otoliths to such a degree that the validity of otolith Sr based migration studies is impaired. Therefore, juvenile eels were reared for 15 weeks at three different water temperatures (14°C, 19°C, 24°C) and the elemental composition of the newly grown aragonite was subsequently analysed. Although the otolith composition differed significantly among treatments, detected differences were low and an in situ reconstruction of temperature history seems challenging. Similar results were obtained in the feeding experiment. Feeding of eight different diets during eight weeks caused no detectable differences in otolith elemental composition among treatments. Hence, the use of otolith microchemistry to determine individual food preferences of European eels seems to be unfeasible. However, the results presented indicate that neither temperature changes nor individual dietary behaviour impair the use of otolith Sr concentrations as a tracer of diadromy. Thus the reliability of such migration studies is fundamentally increased. i SUMMARY In chapter IV it was investigated whether multi-element otolith analysis can be used to discriminate Atlantic cod individuals according to their origin. Therefore, the concentrations of 16 elements were determined along the growth axis of otoliths from adult individuals caught at spawning grounds in the North Sea, the western Baltic Sea and the eastern Baltic Sea. Furthermore, the multi-element composition of the core region of juvenile cod otoliths from western and eastern Baltic areas was analysed. Multivariate statistical analyses successfully discriminated between adults from different stocks as well as between western and eastern Baltic Sea juveniles. Significant differences between the eastern Baltic spawning grounds, however, were not detected. These results demonstrate the potential of otolith microchemistry analysis to investigate the structure and connectivity of G. morhua stocks in the Baltic Sea. In chapter V the migratory behaviour of thicklip grey mullet was examined for the first time on individuals caught in the Baltic Sea. By detecting C. labrosus otolith Sr concentrations, this study aimed to gain first insights into preferences and whereabouts of individuals in the Baltic Sea. Results confirmed a preference of brackish habitats for all analysed specimens and suggest a high plasticity of C. labrosus migratory behaviour. Some individuals seem to undertake annual migrations to marine waters, while others only sporadically left brackish waters. Although the behaviour of Baltic Sea C. labrosus could not be conclusively clarified, the results support the assumption that a considerable fraction of individuals entering the western Baltic Sea regularly migrate to the North Sea. The results presented in this thesis confirm the feasibility of otolith microchemistry analyses for the investigation of a broad range of questions on Baltic Sea fish. Knowledge about investigated species was expanded and opportunities for future studies were indicated. ii ZUSAMMENFASSUNG In dieser Arbeit wurden anhand mikrochemischer Otolithenanalysen Erkenntnisse über die individuelle Lebensweise und die Bestandsstruktur von drei Fischarten aus der Ostsee gewonnen – dem Europäischen Aal Anguilla anguilla, dem Atlantischen Kabeljau (Dorsch) Gadus morhua und der Dicklippigen Meeräsche Chelon labrosus. Die hydrographischen Besonderheiten der Ostsee als weltgrößtes Brackwassersystem bieten vielversprechende Voraussetzungen für die Anwendung von Otolithen-Elementanalysen zur Untersuchung des individuellen Wanderverhaltens von Fischen und deren Bestandsstrukturen. Hier wurden sie genutzt, um managementrelevante Fragestellungen von Fischarten zu untersuchen, die sich hinsichtlich ihrer Biologie, Ökologie und Bestandsstruktur sehr unterscheiden. In Kapitel I wurde der Einfluss des kontinentalen Wanderverhaltens auf die Gesundheit und die Laicherqualität des Europäischen Aals untersucht. Dazu wurden anhand der Otolithen- Strontiumverteilung charakteristische Wandermuster ermittelt. Die Ergebnisse zeigen, dass der Muskelfettgehalt von Blankaalen mit einem strikt katadromen Wanderverhalten signifikant geringer ist als der von Blankaalen, die niemals ins Süßwasser eingewandert sind. Darüber hinaus sind Prävalenz und Befallsintensität mit dem Schwimmblasen-Nematoden Anguillicoloides crassus bei katadromen Blankaalen stark erhöht. Sowohl eine verringerte Einlagerung von Fettreserven als auch der intensive Befall mit A. crassus stehen im Verdacht, den Reproduktionserfolg von A. anguilla zu vermindern. Die vorliegenden Ergebnisse heben die Bedeutung von Brackwasserhabitaten für die Produktion von gesunden Laichtieren hervor und stellen den Nutzen von Besatzmaßnahmen in Binnengewässer in Frage. Um den Einfluss von Wassertemperatur und Futterverhalten auf die Elementeinlagerung in A. anguilla-Otolithen zu prüfen, wurden zwei experimentelle Studien durchgeführt (Kapitel II & III). Es wurde untersucht, ob erlebte Temperaturveränderungen und individuelle Futterpräferenzen anhand der im Otolithen gespeicherten Elemente rekonstruiert werden können. Ferner wurde geprüft, ob Temperatur oder Diät die Einlagerung von Strontium (Sr) in einem Maße beeinflussen, das die Aussagekraft von Otolithen-Sr basierten Migrationsstudien einschränken könnte. Dazu wurden juvenile Aale für 15 Wochen bei drei unterschiedlichen Temperaturen gehalten (14°C, 19°C, 24°C). Anschließend wurde die Elementzusammensetzung des hinzu gewachsenen Aragonits analysiert. Zwar wurden statistisch signifikante Unterschiede in der Elementzusammensetzung verschiedener Temperaturbehandlungen festgestellt, diese waren jedoch so gering, dass eine Rekonstruktion erlebter Temperaturänderungen in situ schwierig erscheint. Zu einem ähnlichen Ergebnis kam auch der Futterversuch. Die Fütterung von acht verschiedenen Diäten über einen Zeitraum von acht Wochen führte zu keinen statistisch iii ZUSAMMENFASSUNG signifikanten Unterschieden in der Elementeinlagerung. Futterpräferenzen lassen sich demnach offenbar nicht anhand der Otolithen-Elementzusammensetzung nachverfolgen. Allerdings zeigen die vorliegenden Ergebnisse, dass beim Europäischen Aal weder Temperaturschwankungen noch unterschiedliches Futterverhalten die Verwendung von Sr zur Rekonstruktion diadromen Verhaltens einschränken. Damit wird die Aussagekraft solcher Migrationsstudien deutlich erhöht. In Kapitel IV wurde untersucht, ob Otolithen-Multielementanalysen dazu geeignet sind, G. morhua-Individuen ihrer Herkunft zuzuordnen. Dazu wurden die Konzentrationen von 16 Elementen entlang der Wachstumsachse von Otolithen adulter Dorsch von Laichplätzen aus der Nordsee, der westlichen und der östlichen Ostsee untersucht. Des Weiteren wurde die Multielementzusammensetzung der Kernbereich von Otolithen juveniler Dorsche aus der westlichen und der östlichen Ostsee analysiert. Multivariate statistische Analysen konnten sowohl die adulten Bestände erfolgreich trennen, als auch die Juvenilen aus der westlichen und der östlichen Ostsee unterscheiden. Signifikante Unterschiede zwischen
Load more

Recommended publications
  • Belonidae Bonaparte 1832 Needlefishes
    ISSN 1545-150X California Academy of Sciences A N N O T A T E D C H E C K L I S T S O F F I S H E S Number 16 September 2003 Family Belonidae Bonaparte 1832 needlefishes By Bruce B. Collette National Marine Fisheries Service Systematics Laboratory National Museum of Natural History, Washington, DC 20560–0153, U.S.A. email: [email protected] Needlefishes are a relatively small family of beloniform fishes (Rosen and Parenti 1981 [ref. 5538], Collette et al. 1984 [ref. 11422]) that differ from other members of the order in having both the upper and the lower jaws extended into long beaks filled with sharp teeth (except in the neotenic Belonion), the third pair of upper pharyngeal bones separate, scales on the body relatively small, and no finlets following the dorsal and anal fins. The nostrils lie in a pit anterior to the eyes. There are no spines in the fins. The dorsal fin, with 11–43 rays, and anal fin, with 12–39 rays, are posterior in position; the pelvic fins, with 6 soft rays, are located in an abdominal position; and the pectoral fins are short, with 5–15 rays. The lateral line runs down from the pectoral fin origin and then along the ventral margin of the body. The scales are small, cycloid, and easily detached. Precaudal vertebrae number 33–65, caudal vertebrae 19–41, and total verte- brae 52–97. Some freshwater needlefishes reach only 6 or 7 cm (2.5 or 2.75 in) in total length while some marine species may attain 2 m (6.5 ft).
    [Show full text]
  • Parks Victoria Technical Series No
    Deakin Research Online This is the published version: Barton, Jan, Pope, Adam and Howe, Steffan 2012, Marine protected areas of the Flinders and Twofold Shelf bioregions Parks Victoria, Melbourne, Vic. Available from Deakin Research Online: http://hdl.handle.net/10536/DRO/DU:30047221 Reproduced with the kind permission of the copyright owner. Copyright: 2012, Parks Victoria. Parks Victoria Technical Paper Series No. 79 Marine Natural Values Study (Vol 2) Marine Protected Areas of the Flinders and Twofold Shelf Bioregions Jan Barton, Adam Pope and Steffan Howe* School of Life & Environmental Sciences Deakin University *Parks Victoria August 2012 Parks Victoria Technical Series No. 79 Flinders and Twofold Shelf Bioregions Marine Natural Values Study EXECUTIVE SUMMARY Along Victoria’s coastline there are 30 Marine Protected Areas (MPAs) that have been established to protect the state’s significant marine environmental and cultural values. These MPAs include 13 Marine National Parks (MNPs), 11 Marine Sanctuaries (MSs), 3 Marine and Coastal Parks, 2 Marine Parks, and a Marine Reserve, and together these account for 11.7% of the Victorian marine environment. The highly protected Marine National Park System, which is made up of the MNPs and MSs, covers 5.3% of Victorian waters and was proclaimed in November 2002. This system has been designed to be representative of the diversity of Victoria’s marine environment and aims to conserve and protect ecological processes, habitats, and associated flora and fauna. The Marine National Park System is spread across Victoria’s five marine bioregions with multiple MNPs and MSs in each bioregion, with the exception of Flinders bioregion which has one MNP.
    [Show full text]
  • Marine Fishes of the Azores: an Annotated Checklist and Bibliography
    MARINE FISHES OF THE AZORES: AN ANNOTATED CHECKLIST AND BIBLIOGRAPHY. RICARDO SERRÃO SANTOS, FILIPE MORA PORTEIRO & JOÃO PEDRO BARREIROS SANTOS, RICARDO SERRÃO, FILIPE MORA PORTEIRO & JOÃO PEDRO BARREIROS 1997. Marine fishes of the Azores: An annotated checklist and bibliography. Arquipélago. Life and Marine Sciences Supplement 1: xxiii + 242pp. Ponta Delgada. ISSN 0873-4704. ISBN 972-9340-92-7. A list of the marine fishes of the Azores is presented. The list is based on a review of the literature combined with an examination of selected specimens available from collections of Azorean fishes deposited in museums, including the collection of fish at the Department of Oceanography and Fisheries of the University of the Azores (Horta). Personal information collected over several years is also incorporated. The geographic area considered is the Economic Exclusive Zone of the Azores. The list is organised in Classes, Orders and Families according to Nelson (1994). The scientific names are, for the most part, those used in Fishes of the North-eastern Atlantic and the Mediterranean (FNAM) (Whitehead et al. 1989), and they are organised in alphabetical order within the families. Clofnam numbers (see Hureau & Monod 1979) are included for reference. Information is given if the species is not cited for the Azores in FNAM. Whenever available, vernacular names are presented, both in Portuguese (Azorean names) and in English. Synonyms, misspellings and misidentifications found in the literature in reference to the occurrence of species in the Azores are also quoted. The 460 species listed, belong to 142 families; 12 species are cited for the first time for the Azores.
    [Show full text]
  • Large Scale Gene Duplication Affected the European Eel (Anguilla 2 Anguilla) After the 3R Teleost Duplication
    bioRxiv preprint doi: https://doi.org/10.1101/232918; this version posted December 12, 2017. The copyright holder for this preprint (which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made available under aCC-BY 4.0 International license. 1 Large scale gene duplication affected the European eel (Anguilla 2 anguilla) after the 3R teleost duplication 3 4 Christoffer Rozenfeld1*, Jose Blanca2*, Victor Gallego1, Víctor García-Carpintero2, Juan Germán 5 Herranz-Jusdado1, Luz Pérez1, Juan F. Asturiano1▲, Joaquín Cañizares2†, David S. 6 Peñaranda1† 7 8 1 Grupo de Acuicultura y Biodiversidad. Instituto de Ciencia y Tecnología Animal. Universitat 9 Politècnica de València. Camino de Vera s/n, 46022 Valencia, Spain 10 2 Instituto de Conservación y Mejora de la Agrodiversidad Valenciana, Universitat Politècnica 11 de València, Camino de Vera 14, 46022, Valencia, Spain. 12 13 Authors marked with * or † contributed equally to this work, respectively. 14 15 16 17 Running title: Evidence of European eel large scale gene duplication 18 19 Keywords: European eel, PHYLDOG, 4dTv, whole genome duplication 20 21 22 23 24 25 ▲ Corresponding author: 26 27 Dr. Juan F. Asturiano 28 Grupo de Acuicultura y Biodiversidad 29 Instituto de Ciencia y Tecnología Animal 30 Universitat Politècnica de València 31 Camino de Vera s/n 46022 Valencia (Spain) 32 E-mail: [email protected] 33 34 35 1 bioRxiv preprint doi: https://doi.org/10.1101/232918; this version posted December 12, 2017. The copyright holder for this preprint (which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity.
    [Show full text]
  • What Goes Wrong During Early Development of Artificially
    animals Article What Goes Wrong during Early Development of Artificially Reproduced European Eel Anguilla anguilla? Clues from the Larval Transcriptome and Gene Expression Patterns Pauline Jéhannet 1, Arjan P. Palstra 1,*, Leon T. N. Heinsbroek 2, Leo Kruijt 1, Ron P. Dirks 3, William Swinkels 4 and Hans Komen 1 1 Animal Breeding and Genomics, Wageningen University & Research, 6708 PB Wageningen, The Netherlands; [email protected] (P.J.); [email protected] (L.K.); [email protected] (H.K.) 2 Wageningen Eel Reproduction Experts B.V., 3708 AB Wageningen, The Netherlands; [email protected] 3 Future Genomics Technologies B.V., 2333 BE Leiden, The Netherlands; [email protected] 4 DUPAN Foundation, 6708 WH Wageningen, The Netherlands; [email protected] * Correspondence: [email protected] Simple Summary: Closing the life cycle of the European eel in captivity is urgently needed to gain perspective for the commercial production of juvenile glass eels. Larvae are produced weekly at our facilities, but large variations in larval mortality are observed during the first week after hatching. Although much effort has been devoted to investigating ways to prevent early larval mortality, it remains unclear what the causes are. The aim of this study was to perform a transcriptomic study Citation: Jéhannet, P.; Palstra, A.P.; on European eel larvae in order to identify genes and physiological pathways that are differentially Heinsbroek, L.T.N.; Kruijt, L.; Dirks, regulated in the comparison of larvae from batches that did not survive for longer than three days R.P.; Swinkels, W.; Komen, H. What vs. larvae from batches that survived for at least a week up to 22 days after hatching (non-viable Goes Wrong during Early vs.
    [Show full text]
  • Actinopterygii Viiib Sarcopterygii VIII
    Základy zoologie strunatců VIII. Osteognathostomata VIIIa Actinopterygii VIIIb Sarcopterygii VIII. Osteognathostomata - čelistnatci s kostní tkání † Placodermi Chondrichthyes † Acanthodii Actinopterygii čelistnatci s kostní tkání (vodní = ryby = Pisces) Sarcopterygii předek ryb – Psarolepis, předek paprskoploutvých - Dialipina Teleostomi Acanthodii Actinopterygii - paprskoploutví Osteognathostomata Sarcopterygii - svaloploutví VIII. Osteognathostomata - čelistnatci s kostní tkání • endochondrální osifikace (kost uvnitř chrupavky na rozdíl od perichondrální os.) • převaha kostí nad chrupavkami, na lebce velký počet dermálních kostí • kostěné skřele (operculum) zakrývají branchiální prostor, napojené na jazylkový oblouk • nové krycí patrové kosti – vomer a parasphenoid • lopatkový pletenec v kontaktu s dermálními kostmi lebky • 3 otolithy ve vnitřním uchu • dolní žebra žaberní váčky žaberní přepážky žaberní oblouky, skřele • kostěné šupiny, postranní čára • žábra nasedají přímo na žaberní oblouky, red. žaberních přepážek • vnější nozdry (nares) rozdělěny mihule paryba kostnatá ryba VIIIa. Actinopterygii - paprskoploutví † Placodermi Chondrichthyes † Acanthodii Actinopterygii Od svrchního siluru (400 mil. let) Sarcopterygii Diverzifikace v devonu, adaptivní radiace: 1.karbon - trias († „Palaeonisciformes“), chrupavčití 2.trias - jura († Semionotus), Holostei – mnohokostnatí 3.jura – dodnes († Pycnodontiformes), Teleostei - kostnatí Diverzita recentních > vymřelých, nejpočetnější skupina obratlovců, 38 řádů, 430 čeledí a ~ 30 000 druhů, původně
    [Show full text]
  • TRAFFIC Bulletin Volume 32, No. 1
    TRAFFIC 1 BULLETIN VOL. 32 NO. 1 32 NO. VOL. TRAFFIC is a leading non-governmental organisation working globally on trade in wild animals and plants in the context of both biodiversity conservation and sustainable development. For further information contact: The Executive Director TRAFFIC David Attenborough Building Pembroke Street Cambridge CB2 3QZ UK Telephone: (44) (0) 1223 277427 E-mail: [email protected] Website: www.traffic.org IMPACT OF TRADE AND CLIMATE CHANGE ON NARWHAL POPULATIONS With thanks to The Rufford Foundation for contributimg to the production costs of the TRAFFIC Bulletin DRIED SEAHORSES FROM AFRICA TO ASIA is a strategic alliance of APRIL 2020 EEL TRADE REVIEW The journal of TRAFFIC disseminates information on the trade in wild animal and plant resources 32(1) NARWHAL COVER FINAL.indd 1 05/05/2020 13:05:11 GLOBAL TRAFFIC was established TRAFFIC International David Attenborough Building, Pembroke Street, Cambridge, CB2 3QZ, UK. in 1976 to perform what Tel: (44) 1223 277427; E-mail: [email protected] AFRICA remains a unique role as a Central Africa Office c/o IUCN, Regional Office for Central Africa, global specialist, leading and PO Box 5506, Yaoundé, Cameroon. Tel: (237) 2206 7409; Fax: (237) 2221 6497; E-mail: [email protected] supporting efforts to identify Southern Africa Office c/o IUCN ESARO, 1st floor, Block E Hatfield Gardens, 333 Grosvenor Street, and address conservation P.O. Box 11536, Hatfield, Pretoria, 0028, South Africa Tel: (27) 12 342 8304/5; Fax: (27) 12 342 8289; E-mail: [email protected] challenges and solutions East Africa Office c/o WWF TCO, Plot 252 Kiko Street, Mikocheni, PO Box 105985, Dar es Salaam, Tanzania.
    [Show full text]
  • Influence of Maternal Effects and Environmental Conditions on Growth and Survival of Atlantic Cod (Gadus Morhua L.)
    Aus dem Leibniz Institut für Meereswissenschaften An der Christian-Albrechts-Universität zu Kiel Influence of maternal effects and environmental conditions on growth and survival of Atlantic cod (Gadus morhua L.) Dissertation zur Erlangung des Doktorgrades der Mathematisch-Naturwissenschaftlichen Fakultät der Christian Albrechts-Universität zu Kiel vorgelegt von Vivian Christiane Buehler Kiel 2004 Influence of maternal effects and environmental conditions on growth and survival of Atlantic cod (Gadus morhua L.) Table of Contents: Acknowledgements 1 1. Introduction 1 1.1 Importance of cod fisheries. 3 1.2 The Northeast Artic cod 4 1.2.1 Characteristics of the NEAC Stock 5 1.2.2 Sex ratio and spawning behaviour of NEAC 6 1.2.3 The offspring of NEAC 7 1.3 Factors that may influence stock management 8 1.4 What is maternal effect? 9 1.5 The MACOM Project 12 2. Materials and Methods 12 2.1 Parental Stock 12 2.1.1 Collecting Fish 12 2.1.2 Breeding 13 2.1.3 Incubation 14 2.1.4 Egg quality measurements 14 2.2 Mesocosm Experiment 14 2.2.1 Characteristics of the mesocosms 15 2.2.2 Monitoring of biotic and abiotic parameters 16 2.2.3 Transport and arrival of the larvae in Flødevigen 17 2.2.4 Releasing of larvae in the mesocosms 18 2.2.5 Sampling of cod larvae in the mesocosms 18 2.2.6 Termination of the Mesocosm Experiment 18 2.2.7 Mortality Calculation 19 2.3 Rearing of Juveniles in Indoor Tanks 20 2.3.1 Fish Tagging and fin clipping 20 2.3.2 Fish Measurements 21 2.3.3 Termination of the tanks Experiment 21 2.3.3.1 Estimation of oocytes size and Potential Fecundity 22 2.4 Laboratory Examinations 23 2.4.1 Otolith microstructure analysis 23 2.4.1.1 Otolith Preparation 23 2.4.1.2 Otolith reading 24 2.4.2 RNA/DNA ratio and glycolytic enzymes 24 2.4.3 DNA Fingerprinting 26 2.5 Statistical Analysis 27 3.
    [Show full text]
  • Diet, Food Preference, and Algal Availability for Fishes and Crabs on Intertidal Reef Communities in Southern California
    Environmental Biology of Fishes 37: 75-95,1993. 0 1993 Kluwer Academic Publishers. Printed in the Netherlands. Diet, food preference, and algal availability for fishes and crabs on intertidal reef communities in southern California James P. Barry’ & Michael J. Ehret* A-001 Scripps Institution of Oceanography, La Jolla, CA 92093, U.S.A. ‘Present address: Monterey Bay Aquarium Research Institute, 160 Central Ave., Pacific Grove, CA 93950, U.S.A. 2 Present address: Biology Department, Old Dominion University, Norfolk, VA 23507, U.S. A. Received 18.9.1991 Accepted 3.9.1992 Key words: Herbivory, Kyphosidae, Girella, Hermosilla, Pachygrapsus, Community structure, Foraging, Chemical ecology Synopsis Herbivory by wide-ranging fishes is common over tropical reefs, but rare in temperate latitudes where the effects of herbivorous fishes are thought to be minimal. Along the west coast of North America, herbivory by fishes on nearshore reefs is largely restricted to a few members of the Kyphosidae, distributed south of Pt. Conception. This paper presents information on natural diets and results from feeding choice experiments for two abundant kyphosids from intertidal habitats in San Diego, California - Girella nigricans and Hermosilla azurea, and similar data for the lined shore crab, Pachygrapsus crassipes, which also forages over intertidal reefs. These results are compared with the availability of algae in intertidal habitats measured during summer and winter, on both disturbed and undisturbed habitats. The diets of juveniles of G. nigricans and H. azurea collected from nearshore habitats were dominated by animal prey (mainly amphipods), but adults of these fishes, and P. crassipes, consumed algae nearly exclusively, with 26,10, and 14 taxa of algae identified from G.
    [Show full text]
  • Zootaxa, a New Species of Snapper
    Zootaxa 1422: 31–43 (2007) ISSN 1175-5326 (print edition) www.mapress.com/zootaxa/ ZOOTAXA Copyright © 2007 · Magnolia Press ISSN 1175-5334 (online edition) A new species of snapper (Perciformes: Lutjanidae) from Brazil, with comments on the distribution of Lutjanus griseus and L. apodus RODRIGO L. MOURA1 & KENYON C. LINDEMAN2 1Conservation International Brasil, Programa Marinho, Rua das Palmeiras 451 Caravelas BA 45900-000 Brazil E-mail:[email protected] 2Environmental Defense, 485 Glenwood Avenue, Satellite Beach, FL, 32937 USA E-mail: [email protected] Abstract Snappers of the family Lutjanidae contain several of the most important reef-fishery species in the tropical western Atlantic. Despite their importance, substantial gaps exist for both systematic and ecological information, especially for the southwestern Atlantic. Recent collecting efforts along the coast of Brazil have resulted in the discovery of many new reef-fish species, including commercially important parrotfishes (Scaridae) and grunts (Haemulidae). Based on field col- lecting, museum specimens, and literature records, we describe a new species of snapper, Lutjanus alexandrei, which is apparently endemic to the Brazilian coast. The newly settled and early juvenile life stages are also described. This spe- cies is common in many Brazilian reef and coastal estuarine systems where it has been often misidentified as the gray snapper, Lutjanus griseus, or the schoolmaster, L. apodus. Identification of the new species cast doubt on prior distribu- tional assumptions about the southern ranges of L. griseus and L. apodus, and subsequent field and museum work con- firmed that those species are not reliably recorded in Brazil. The taxonomic status of two Brazilian species previously referred to Lutjanus, Bodianus aya and Genyoroge canina, is reviewed to determine the number of valid Lutjanus species occurring in Brazil.
    [Show full text]
  • ! Osteichthyes ! Osteichthyes
    ! Osteichthyes ! Osteichthyes = Osteognathostomata- = Osteognathostomata- Ryby s.str.a Tetrapoda Ryby s.str.a Tetrapoda =Teleostomi – Koncoústé =Teleostomi – Koncoústé ryby …ale ryby …ale - Agnatha - Gnathostomata Sarcopterygii Osteognathostomata - Chondrichtyes Actinopterygii Teleostomi - Osteognathostomata †Acanthodii - Actinopterygii Chondrichthyes - Sarcopterygii †Placodermi Osteichthyes = Osteognathostomata (jméno Osteognathostomata: akcentující zahrnutí Tetrapoda) *lepidotrichia (dermální, kostěné), *šupiny s isopedinem (lamelární kost) • Endochondrální osifikace endoskeletu *dermatokranium jednotné • výrazný rozvoj a specialisace exoskeletu základní stavby, *jícnové výchlipky • Malý počet otolitů (3) v blanitém labyrintu (srv. otokonia u paryb) • Žaberní přepážky redukovány, společná žaberní dutina nebo vnější žábra lepidotrichia – • Výchlipky jícnu (plíce +/vs. plynový měchýř) kostěné, dermální, párové • lepidotrichia Osteognathostomata • Monophylum: Actinopterygii+ Sarcopterygii • Jícnová výchlipka (ventr. –plíce, dors. plynový měchýř) • Ztráta interbranchiálních sept • Lepidotrichia Šupiny ryb: • Endoskelet s peri- a endochondrální osifikací Kosmoidní (Sarcopterygii – • Dermální skelet (extrascapularia – kaud okraj zejm.fosilní), stropu lebky, praeoperculare +preoperculární kanál – začátek postr. čáry, operkulární komplex, gularia, Ganoidní (bichiři, kostlíni…) premaxilare, maxillare, qudratojugale, dentale, Leptoidní – kostěnné infrraorbitalia, temporalia, frontale, parietale, (Teleostei): cykloidní, parasphenoid, vomer, interclavicula,
    [Show full text]
  • The European Eel Anguilla Anguilla (Pisces, Anguillidae). Native Or Alien in the Black Sea?
    View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Directory of Open Access Journals ECOLOGIA BALKANICA 2013, Vol. 5, Issue 2 December 2013 pp. 57-62 The European Eel Anguilla anguilla (Pisces, Anguillidae). Native or Alien in the Black Sea? Apostolos I. Apostolou*, Boris K. Velkov, Milen V. Vassilev Institute of Biodiversity and Ecosystem Research Bulgarian Academy of Sciences, 2 Gagarin Street, 1113 Sofia, BULGARIA * Corresponding author: [email protected] Abstract. In 2006 the Scientific, Technical and Economic Committee for Fisheries (STEFC) of EU suggested the Black Sea region should be excluded from the list of natural areas, where the European eel (Anguilla anguilla) is distributed. The basic conception of this idea was that the eels caught in the Black Sea region represent escaped specimens from fish farming in some Danubian countries. This article illustrates an effort to be given an indirect answer on the question if Black Sea is the end of natural distribution of European eel. The species is present but never been abundant in the region and do not represent an object of commercial fishing. Key words: European eel, Anguilla anguilla, Black Sea Region Introduction south of Bermuda in the Sargasso Sea, where The life cycle of the eel was a mystery he succeeded in catching the smallest eel- for a very long period of scientific history - larvae ever seen. However, Schmidt was not more than 6500 publications about the eel, able to observe the spawning directly, nor but still much of its life history is enigmatic. did he find ready-to-spawn adults.
    [Show full text]