Cephalopod Resources of Venezuela
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Signs of an Extended and Intermittent Terminal Spawning In
View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Digital.CSIC Signs of an extended and intermittent terminal spawning in the squids Loligo vulgaris Lamarck and Loligo forbesi Steenstrup (Cephalopoda: Loliginidae) Francisco Rocha*, Angel Guerra Instituto de Investigaciones Marinas (CSIC), C/ Eduardo Cabello 6, 36208 Vigo, Spain *Corresponding author. Tel.: + 34 86 231930; Fax: +34 86 292762 Abstract The reproductive pattern of Loligo vulgaris and Loligo forbesi was studied on the basis of gonad maturation, mating and spawning in males and females of both species which were present off the northwest coast of Spain (Galicia), between February 1991 and February 1993. The mature females of both species have several modes of egg sizes and developmental stages within the ovary. Several signs indicate that both female Loligo vulgaris and L. forbesi undergo partial ovulation at the time of spawning, the spawning period being relatively long, although in no case representing the greatest fraction of the animal’s life before death. Egg-laying occurring in separate batches and somatic growth between egg batchs has not been observed. This reproductive pattern is defined as intermittent terminal spawning. Some other terms describing different cephalopod reproductive strategies are also defined. Keywords: Loligo forbesi; Loligo vulgaris; NW Atlantic; Reproduction; Spawning patterns 1. Introduction Until recently, it was generally accepted that female cephalopods lay their eggs in one single spawning or in several consecutive ones, with no pause between each, after which they would die by exhaustion (McGowan, 1954; Mangold, 1987; Harman et al., 1989; Mangold et al., 1993). -
1. Natural History of the Squid
1. Natural History of the Squid INTRODUCTION Cephalopods in general and squid in particular have been the subject of con- siderable curiosity everywhere that man has become acquainted with the sea. These fast-moving animals possess a number of features usually associated only with verte- brate forms and to practitioners of anthropomorphism they appear to have con- siderable cunning. Popular accounts of these animals are recurrent and only a few wil be mentioned to introduce the subject: Lane (1957) provided a comprehensive and readable coverage of cephalopods in a book slanted toward Octopus; Morton's (1958) introduction to mollusks sets the cephalopods among other members of the phylum; some invertebrate zoology tests, especially one by Russell-Hunter (1968), give good coverage of cephalopods; excellent photographic coverage can be found in articles by Voss and Sisson (1967 and 1971); and behavioral aspects of cephal- opods are summarized in a concise book by Wells (1962). Systematic position Cephalopods are relatively large, active, predaceous mollusks with a high level of nervous development. There are approximately 400 living species which are distributed throughout all marine environments. Fossils of shelled cephalopods are well known and abundant in the Paleozoic and Mesozoic; their direct descendants are almost entirely extinct today, having been replaced by shell-less cephalopods which did not leave a fossil record. Modern forms are subdivided into the Nautiloi- dea (including only the relict genus Nautilus) and the Coleoidea, encompassing the remaining dibranchiate species. The latter are composed of eight-armed forms (Octopoda) and ten-armed forms (Decapoda) which include the true squids (Teu- thoidea) and cuttlefishes (Sepioidea). -
PATTERNS of PREY BIOMASS CONSUMPTION by SMALL ODONTOCETES in the NORTHEASTERN COAST of VENEZUELA Lenin E
PATTERNS OF PREY BIOMASS CONSUMPTION BY SMALL ODONTOCETES IN THE NORTHEASTERN COAST OF VENEZUELA Lenin E. Oviedo Correa1,2 ABSTRACT Trophic relationships are conditioned by population dynamics of interacting species in the commu- nity (species present, food web connections among them, and the strength of interactions), and on the consequences of these species interactions depend various ecosystem processes such as productivity and nutrient flux. Odontocetes target a wide range of prey items and are adapted to feeding at dif- ferent depths. The aim of this report is to describe the patterns of prey consumption by small odon- tocetes, incorporating natural predatory patterns into a potential management scheme of strategic food sources, for both human and marine predators. Using the geo-statistical analysis tool of ArcGIS 9.2, maps illustrating the intensity and location of prey consumption were made for species with a sighting index (SPUE) > 0.15. The biomass consumption emphasized the differences in habitat use by species. The trends in distribution of prey biomass removal by odontocetes particularly suggest a stratification of prey consumption primarily in shelf waters, with a prey biomass that is comprised basically by demersal fish and small pelagics (includingSardinella aurita), and into transition-oce- anic depths where most of the predatory pattern would potentially rely on pelagic - mesopelagic squid and myctophids. Overall the spatial tendencies in regionalization presented in this contribution will serve as a base-line to assess ecosystem health and evaluate management scenarios. Keywords: Atlantic ocean; distribution; food/prey; ecosystem; habitat. RESUMEN Las relaciones tróficas son reguladas por la dinámica poblacional de las especies que interactúan dentro de la comunidad (especies presentes, conexiones interespecíficas, y nivel de interacción) y de las consecuencias de esas interacciones para procesos del ecosistema como la productividad y el flujo de nutrientes. -
An Illustrated Key to the Families of the Order
CLYDE F. E. ROP An Illustrated RICHARD E. YOl and GILBERT L. VC Key to the Families of the Order Teuthoidea Cephalopoda) SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY • 1969 NUMBER 13 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY NUMBER 13 Clyde F. E. Roper, An Illustrated Key 5K?Z" to the Families of the Order Teuthoidea (Cephalopoda) SMITHSONIAN INSTITUTION PRESS CITY OF WASHINGTON 1969 SERIAL PUBLICATIONS OF THE SMITHSONIAN INSTITUTION The emphasis upon publications as a means of diffusing knowledge was expressed by the first Secretary of the Smithsonian Institution. In his formal plan for the Institution, Joseph Henry articulated a program that included the following statement: "It is proposed to publish a series of reports, giving an account of the new discoveries in science, and of the changes made from year to year in all branches of knowledge not strictly professional." This keynote of basic research has been adhered to over the years in the issuance of thousands of titles in serial publications under the Smithsonian imprint, commencing with Smithsonian Contributions to Knowledge in 1848 and continuing with the following active series: Smithsonian Annals of Flight Smithsonian Contributions to Anthropology Smithsonian Contributions to Astrophysics Smithsonian Contributions to Botany Smithsonian Contributions to the Earth Sciences Smithsonian Contributions to Paleobiology Smithsonian Contributions to Zoology Smithsonian Studies in History and Technology In these series, the Institution publishes original articles and monographs dealing with the research and collections of its several museums and offices and of professional colleagues at other institutions of learning. These papers report newly acquired facts, synoptic interpretations of data, or original theory in specialized fields. -
Defensive Behaviors of Deep-Sea Squids: Ink Release, Body Patterning, and Arm Autotomy
Defensive Behaviors of Deep-sea Squids: Ink Release, Body Patterning, and Arm Autotomy by Stephanie Lynn Bush A dissertation submitted in partial satisfaction of the requirements for the degree of Doctor of Philosophy in Integrative Biology in the Graduate Division of the University of California, Berkeley Committee in Charge: Professor Roy L. Caldwell, Chair Professor David R. Lindberg Professor George K. Roderick Dr. Bruce H. Robison Fall, 2009 Defensive Behaviors of Deep-sea Squids: Ink Release, Body Patterning, and Arm Autotomy © 2009 by Stephanie Lynn Bush ABSTRACT Defensive Behaviors of Deep-sea Squids: Ink Release, Body Patterning, and Arm Autotomy by Stephanie Lynn Bush Doctor of Philosophy in Integrative Biology University of California, Berkeley Professor Roy L. Caldwell, Chair The deep sea is the largest habitat on Earth and holds the majority of its’ animal biomass. Due to the limitations of observing, capturing and studying these diverse and numerous organisms, little is known about them. The majority of deep-sea species are known only from net-caught specimens, therefore behavioral ecology and functional morphology were assumed. The advent of human operated vehicles (HOVs) and remotely operated vehicles (ROVs) have allowed scientists to make one-of-a-kind observations and test hypotheses about deep-sea organismal biology. Cephalopods are large, soft-bodied molluscs whose defenses center on crypsis. Individuals can rapidly change coloration (for background matching, mimicry, and disruptive coloration), skin texture, body postures, locomotion, and release ink to avoid recognition as prey or escape when camouflage fails. Squids, octopuses, and cuttlefishes rely on these visual defenses in shallow-water environments, but deep-sea cephalopods were thought to perform only a limited number of these behaviors because of their extremely low light surroundings. -
Geographic and Temporal Patterns in Size and Maturity of the Longfin Inshore Squid (Loligo Pealeii) Off the Northeastern United States
Geographic and temporal patterns in size and maturity of the longfin inshore squid (Loligo pealeii) off the northeastern United States Item Type article Authors Hatfield, Emma M.C.; Cadrin, Steven X. Download date 04/10/2021 18:55:59 Link to Item http://hdl.handle.net/1834/31057 200 Abstract–Analysis of 32 years of stan Geographic and temporal patterns dardized survey catches (1967–98) indi cated differential distribution patterns in size and maturity of the longfin inshore squid for the longfin inshore squid (Loligo pealeii) over the northwest Atlantic (Loligo pealeii) off the northeastern United States U.S. continental shelf, by geographic region, depth, season, and time of day. Emma M.C. Hatfield Catches were greatest in the Mid- Atlantic Bight, where there were sig Steven X. Cadrin nificantly greater catches in deep water Northeast Fisheries Science Center during winter and spring, and in National Marine Fisheries Service, NOAA shallow water during autumn. Body 166 Water Street size generally increased with depth Woods Hole, Massachusetts 02543 in all seasons. Large catches of juve Present address (for E.M.C. Hatfield): FRS Marine Laboratory niles in shallow waters off southern Victoria Road New England during autumn resulted Aberdeen AB11 9DB from inshore spawning observed during Scotland, United Kingdom late spring and summer; large propor E-mail address (for E. M. C. Hatfield): e.hatfi[email protected] tions of juveniles in the Mid-Atlantic Bight during spring suggest that sub stantial winter spawning also occurs. Few mature squid were caught in sur vey samples in any season; the major ity of these mature squid were cap tured south of Cape Hatteras during The longfin inshore squid, Loligo pea- mers, 1967; 1969; Serchuk and Rathjen, spring. -
Interannual Variation in Life-Cycle Characteristics of the Veined Squid (Loligo Forbesi). ICES CM 2004/CC:31
Not to be cited without prior reference to the authors ICES CM 2004/CC:31 Interannual variation in life-cycle characteristics of the veined squid (Loligo forbesi) G.J. Pierce, A.F. Zuur, J.M. Smith, M.B. Santos, N. Bailey & P.R. Boyle The loliginid squid Loligo forbesi has a flexible life-cycle, involving variable size and age at maturity, presence of summer and winter breeding populations, and extended periods of breeding and recruitment. This paper reviews life history data collected since 1983 from the commercial fishery in Scottish (UK) waters and examines (a) the relationship between size and timing of maturation, (b) evidence for shifts in the relative abundance of the summer and winter breeding populations, and (c) the role of environmental signals in determining the timing of breeding. Evidence from fishery data suggests that, since the 1970s, the summer breeding population has declined while the winter breeding population now dominates and breeds later than was previously the case. Length-weight relationships and size at maturity showed significant inter-annual and seasonal variation during the period 1983-2001 and provide no evidence that there is currently a summer breeding population. Males are shown to decline in relative weight as they mature while females increase in relative weight. There is evidence that timing of breeding and size at maturity are related to environmental variation (winter NAO index). Key words: life history, time series, environmental factors G.J. Pierce, J.M. Smith, M.B. Santos, P.R. Boyle: University of Aberdeen, Tillydrone Avenue, Aberdeen AB24 2TZ, UK [tel: +44 1224 272866, fax: +44 1224 272396, e-mail: [email protected]]. -
Age and Growth of Two Sympatric Squid Loligo Vulgaris and Loligo Forbesi, in Galician Waters (North-West Spain)
J. Mar. Biol. Ass. U.K. (1999), 79, 697^707 Printed in the United Kingdom Age and growth of two sympatric squid Loligo vulgaris and Loligo forbesi, in Galician waters (north-west Spain) F. Rocha and A. Guerra Instituto de Investigaciones Marinas (CSIC), Eduardo Cabello 6, 36208 Vigo, Spain Age and growth of Loligo vulgaris and L. forbesi were studied by the examination of growth increments in 96 and 135 selected (white zone 510%) statoliths, respectively. Squid were obtained by monthly sampling from the catches of commercial trawling and hand-jigs in Galician waters (north-west Spain) between February 1991 and October 1993. Mantle length (ML) of L. vulgaris ranged from 70 to 480 mm and varied between 70 and 685 mm in L. forbesi. A negative allometry between statolith length and ML or body weight (BW) was found in both species. Sexual dimorphism was apparent in both species, males grew faster and longer than females. The statolith analysis suggests that growth patterns of L. vulgaris and L. forbesi in Galician waters are di¡erent. The exploited population of L. vulgaris was composed of two groups: one formed by individuals hatched in winter^spring and another by specimens hatched in summer^autumn. Squid hatched in winter^spring reached larger sizes at the same age than those hatched in summer^autumn. These two groups were also observed in L. forbesi. However, squid of this species hatched in winter^spring were smaller than those hatched in summer^autumn at the same age. Reasons for this discrepancy are discussed. The life span of L. -
ON 20 (1) Zager Et Al.Fm
ORNITOLOGIA NEOTROPICAL 20: 99–112, 2009 © The Neotropical Ornithological Society NEST POACHING IN THE VENEZUELAN INSULAR SUBSPECIES OF THE BROWN-THROATED PARAKEET (ARATINGA PERTINAX) Irene Zager1,2, Kathryn M. Rodríguez-Clark1*, Jessica R. Eberhard3, Jon Paul Rodríguez2,4, & Pablo A. Millán2 1Laboratorio de Ecología y Genética de Poblaciones, Centro de Ecología, Instituto Venezolano de Investigaciones Científicas (IVIC), Apartado 20632, Caracas 1020-A, Venezuela. *E-mail: [email protected], [email protected] 2Provita, Apartado 47552, Caracas 1041-A, Venezuela. 3Department of Biological Sciences and Museum of Natural Science, Louisiana State University, Baton Rouge, Louisiana 70803, USA. 4Laboratorio de Biología de Organismos, Centro de Ecología, Instituto Venezolano de Investigaciones Científicas (IVIC), Apartado 20632, Caracas 1020-A, Venezuela. Resumen. – Saqueo de nidos en las subespecies insulares venezolanas del Perico Cara Sucia (Aratinga pertinax). – Durante mucho tiempo se ha sospechado el declive del Perico Cara Sucia en las islas venezolanas de La Tortuga y Margarita, debido al saqueo de pichones para el tráfico ilegal de mas- cotas, y por la destrucción de sitios de anidación resultante. Por eso, evaluamos el estatus de las dos subespecies involucradas, Aratinga pertinax margaritensis y A. p. tortuguensis, y examinamos la amenaza que representa el saqueo de nidos. Durante trabajos de campo en 2004, caracterizamos los patrones de los dormideros y sitios de anidación en las dos islas, y estimamos el tamaño poblacional de A. p. margaritensis. En la Isla Margarita, encontramos una población considerable (de por lo menos 1984 individuos), pero los 25 nidos encontrados sufrieron una tasa alta de saqueo (64%) y de destruc- ción (32%). Dado que los ùnicos dos dormideros activos de esta subespecie se ubicaron cercanos a o dentro del Parque Nacional Laguna de La Restinga, que también sufre de presiones antrópicas, nues- tros resultados sugieren que esta subespecie se clasifica en el presente como En Peligro (B1a&b[v]). -
Cenozoic Kinematics and Dynamics of Oblique Collision Between Two Convergent Plate Margins: the Caribbean-South America Collisio
Cenozoic Kinematics and Dynamics of Oblique Collision Between two Convergent Plate Margins: The Caribbean-South America Collision in Eastern Venezuela, Trinidad and Barbados James Pindell and Lorcan Kennan Tectonic Analysis, Ltd., Chestnut House, Duncton West Sussex, GU28 0LH, UK Email: [email protected] Abstract Numerous structural, tectonic, and geometric aspects of the Eastern South Caribbean Plate Boundary Zone are assessed or reassessed in the light of seismic reflection data, field studies from 2000-2007, heavy mineral analysis, updated interpretation of seismic tomography, seismicity, GPS data, and refined plate kinematic constraints for the Cenozoic. We show that the Cretaceous passive margin of northern South America was transformed to a north-facing, slowly convergent margin in the Late Maastrichtian, and that the collision between the Caribbean and South America was a collision of two convergent margins above an intervening, “doubly subducting” Proto-Caribbean oceanic lithosphere. The new assessments are iteratively integrated to create semi-quantitative palinspastic reconstructions for 5, 10, 25, 31 and 42 Ma, on which paleogeographies are developed. The origin of key sandstone units are considered, due to their importance as major reservoirs, as well as the implications of the kinematic and dynamic modeling for structural timing. The primary collision between the two plates was completed by 10 Ma, with subsequent motion being essentially E-W strike slip, the deformations of which are driven mainly in a bow-wave model of transcurrent simple shear. Pindell and Kennan, SE Caribbean, Trinidad & Venezuela, for GCSSEPM 2007 1 of 76 Introduction We present an updated synthesis of the tectonic processes and stages of history that have shaped Eastern Venezuela and Trinidad during Cenozoic time. -
Geographic Drivers of Diversification in Loliginid Squids with an Emphasis on the Western Atlantic Species
bioRxiv preprint doi: https://doi.org/10.1101/2020.07.20.211896; this version posted July 21, 2020. 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-NC-ND 4.0 International license. 1 Original Article Geographic drivers of diversification in loliginid squids with an emphasis on the western Atlantic species Gabrielle Genty1*, Carlos J Pardo-De la Hoz1,2*, Paola Montoya1,3, Elena A. Ritschard1,4* 1Departamento de Ciencias Biológicas, Universidad de los Andes, Bogotá D.C, Colombia. 2Department of Biology, Duke University, Durham, North Carolina, 27708, United States of America 3Instituto de Investigación de Recursos Biológicos Alexander von Humboldt, Bogotá, D.C., Colombia 4Department of Neuroscience and Developmental Biology, University of Vienna, Austria * These authors contributed equally to this work. Correspondence author: Gabrielle Genty, [email protected] Acknowledgements We would like to thank Daniel Cadena and Andrew J. Crawford for their suggestions and guidance during the early stages of this investigation. bioRxiv preprint doi: https://doi.org/10.1101/2020.07.20.211896; this version posted July 21, 2020. 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-NC-ND 4.0 International license. 2 ABSTRACT Aim: Identifying the mechanisms driving divergence in marine organisms is challenging as opportunities for allopatric isolation are less conspicuous than in terrestrial ecosystems. -
Trade and the Conservation Status of the Family Psittacidae in Venezuela
Bird Conservation International (1991) 1:153-169 Trade and the conservation status of the family Psittacidae in Venezuela PHILIP DESENNE and STUART D. STRAHL Summary An assessment of trade in parrots throughout Venezuela, 1988-1989, reveals alarmingly high internal and international levels. The national trade has main outlets in major cities, but is now compounded by the use of feathers for Indian artifacts sold to tourists. International trade involves illegal export chiefly from the Orinoco Delta, the majority of such birds (65,000-75,000) destined for Guyana. The large macaws suffer badly from both types of trade, but owing to its restricted range the endemic Amazona barbadensis is perhaps the most critically threatened species. Other species are assessed and, along with key sites, identified in priority order for remedial action, which should include more detailed field studies, rigorous trade data analysis, exchange of trade data with major neighbours, census and monitoring technique improvements, educational campaigns, and strict breeding facility control. Un estudio sobre el comercio de periquitos en Venezuela 1988-1989 ha revelado un nivel alarmante de comercio national e international. La red de comercio national tiene puntos de venta importantes en las ciudades principales. Comercio ha incrementado debido al uso de plumas en artefactos indios de venta a turistas. El comercio international consiste principalmente en la exportation ilegal de periquitos de la Delta de Orinoco, la mayoria (65,000-75,000), destinados a Guayana. Los periquitos grandes se ven muy afectados por los dos tipos de comercio, pero dado su muy limitada distribution, el endemico Amazona barbadensis es talvez la especie mas amenazada.