The ecology of the horned octopus, Eledone cirrhosa (Lamarck, 1798) in Atlantic Iberian Waters

204 pages

Bibliographic Details
Author: Regueira, Marcos
Format: doctoral thesis
Publication Date:2017
Country:España
Institution:Consejo Superior de Investigaciones Científicas (CSIC)
Repository:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/157895
Online Access:http://hdl.handle.net/10261/157895
Access Level:Open access
Keyword:Cephalopods
Eledone cirrhosa
Ecology
Reproductive cycle
Growth
Age
Distribution
Diet
NW Iberian peninsula
NE Atlantic
id ES_ec91c5686293f227a43dc861f5dbbd95
oai_identifier_str oai:digital.csic.es:10261/157895
network_acronym_str ES
network_name_str España
repository_id_str
dc.title.none.fl_str_mv The ecology of the horned octopus, Eledone cirrhosa (Lamarck, 1798) in Atlantic Iberian Waters
Ecologia do polvo-do-alto Eledone cirrhosa (Lamarck, 1798) no Atlántico Ibérico
Ecología del pulpo blanco Eledone cirrhosa (Lamarck, 1798) en el Atlántico Ibérico
title The ecology of the horned octopus, Eledone cirrhosa (Lamarck, 1798) in Atlantic Iberian Waters
spellingShingle The ecology of the horned octopus, Eledone cirrhosa (Lamarck, 1798) in Atlantic Iberian Waters
Regueira, Marcos
Cephalopods
Eledone cirrhosa
Ecology
Reproductive cycle
Growth
Age
Distribution
Diet
NW Iberian peninsula
NE Atlantic
title_short The ecology of the horned octopus, Eledone cirrhosa (Lamarck, 1798) in Atlantic Iberian Waters
title_full The ecology of the horned octopus, Eledone cirrhosa (Lamarck, 1798) in Atlantic Iberian Waters
title_fullStr The ecology of the horned octopus, Eledone cirrhosa (Lamarck, 1798) in Atlantic Iberian Waters
title_full_unstemmed The ecology of the horned octopus, Eledone cirrhosa (Lamarck, 1798) in Atlantic Iberian Waters
title_sort The ecology of the horned octopus, Eledone cirrhosa (Lamarck, 1798) in Atlantic Iberian Waters
dc.creator.none.fl_str_mv Regueira, Marcos
author Regueira, Marcos
author_facet Regueira, Marcos
author_role author
dc.contributor.none.fl_str_mv González, A. F.
Consejo Superior de Investigaciones Científicas [https://ror.org/02gfc7t72]
dc.subject.none.fl_str_mv Cephalopods
Eledone cirrhosa
Ecology
Reproductive cycle
Growth
Age
Distribution
Diet
NW Iberian peninsula
NE Atlantic
topic Cephalopods
Eledone cirrhosa
Ecology
Reproductive cycle
Growth
Age
Distribution
Diet
NW Iberian peninsula
NE Atlantic
description 204 pages
publishDate 2017
dc.date.none.fl_str_mv 2017
2017
2017
dc.type.none.fl_str_mv info:eu-repo/semantics/doctoralThesis
http://purl.org/coar/resource_type/c_db06
format doctoralThesis
dc.identifier.none.fl_str_mv http://hdl.handle.net/10261/157895
url http://hdl.handle.net/10261/157895
dc.language.none.fl_str_mv Inglés
language_invalid_str_mv Inglés
dc.relation.none.fl_str_mv Sí
dc.rights.none.fl_str_mv info:eu-repo/semantics/openAccess
eu_rights_str_mv openAccess
dc.publisher.none.fl_str_mv Universidade de Aveiro
publisher.none.fl_str_mv Universidade de Aveiro
dc.source.none.fl_str_mv reponame:DIGITAL.CSIC. Repositorio Institucional del CSIC
instname:Consejo Superior de Investigaciones Científicas (CSIC)
instname_str Consejo Superior de Investigaciones Científicas (CSIC)
reponame_str DIGITAL.CSIC. Repositorio Institucional del CSIC
collection DIGITAL.CSIC. Repositorio Institucional del CSIC
repository.name.fl_str_mv
repository.mail.fl_str_mv
_version_ 1869423326002151424
spelling The ecology of the horned octopus, Eledone cirrhosa (Lamarck, 1798) in Atlantic Iberian WatersEcologia do polvo-do-alto Eledone cirrhosa (Lamarck, 1798) no Atlántico IbéricoEcología del pulpo blanco Eledone cirrhosa (Lamarck, 1798) en el Atlántico IbéricoRegueira, MarcosCephalopodsEledone cirrhosaEcologyReproductive cycleGrowthAgeDistributionDietNW Iberian peninsulaNE Atlantic204 pagesThis Ph.D. Dissertation deals on the study of several aspects of the ecology of the horned octopus Eledone cirrhosa (Lamark, 1798) in the NW Iberian Peninsula, from western gulf of Biscay to north Portugal. The horned octopus is a benthic octopod distributed along the continental shelf and slope throughout the Mediterranean and northeast Atlantic from Morocco to Norway, including the British Isles and Iceland. In the NW Iberian Peninsula this species is considered as a by-catch of trawling fishery, mainly targeting hake (Merluccius merluccius), monkfish (Lophius sp.) and Norway lobster (Nephrops norvegicus). Horned octopus landings show a cyclical pattern consistent with its life cycle, and its commercial interest considerably varies throughout its geographic range. According to ICES reports, landings of E. cirrhosa in VIIIc and IXa north subareas reached 1145 t in 2013. In terms of both body size and main reproductive parameters (such as maturation, fecundity, and eggs/spermatophores size), specimens of E. cirrhosa from northwest Iberian Peninsula have intermediate characteristics to those exhibited by individuals from the north-eastern Atlantic Ocean and those from the Mediterranean Sea, suggesting some gradation on environmental conditions. This gradient, in turn, was also found in our study area. During the sampling, carried out over two years, a significant bias was observed in the relative abundance between sexes, always favourable to females. The spawning season of the species also varies throughout its range. Specifically, in the northwest Iberian it concentrates in May and June. Similarly to the maximum size, the size-at-maturity increased with latitude. This population parameter ranged from 100 to 134 mm mantle length (ML) for females and between 91 and 108 mm ML for males, depending on the fishing groundThe analysis of catches per unit effort (CPUE) obtained from scientific surveys and carried out at different times of the reproductive cycle of the species shows the existence of spatio-temporal variations on its distribution and abundance in the northwest Iberian sector. The geostatistical modelling of catches depicts the seasonal migration performed by mature individuals to shallower waters during the spawning season. The diet of the horned octopus in the north-western Iberian Peninsula was studied for the first time by combining visual and molecular analysis of stomach contents. The diet of E. cirrhosa in the area was mainly composed by crustaceans (74.64%), followed by fish (16.84%) and, to a lesser extent echinoderms (5.51%), mollusks (4.92%) and polychaetes (2.09%). Multinomial logistic regression (MLR) was used for modelling feeding trends of the species. According to it, the main factors affecting feeding patterns were maturity stage, fishing ground and season. The obtained results, in combination with the previous literature on the distribution of prey, suggest that E. cirrhosa is not a totally opportunistic hunter, but rather a selective generalist. The age of E. cirrhosa was estimated for the first time by stylet increment analysis. A total of 122 individuals, ranging from 67 to 950 g, were selected from a total sample of 2220 specimens using a modal progression analysis (MPA), in order to represent all size classes. The estimated age ranged from 106-516 days and females were significantly more long-lived (17 months) than males (14 months). Based on the estimated ages, hatching date was back-calculated, concluding that hatchings, although occur throughout the year, are mostly concentrated during winter. The instantaneous relative growth rate, i.e. the increase in % body weight per day, estimated for age classes of 90 days, ranged between 0.03% and 2.17%, decreasing throughout the development of individualsNew behavioural information on this species is provided based on the observation of live specimens under confined conditions. E. cirrhosa spontaneously spawned within the shelters arranged inside the tanks. The species do nesting and care their eggs in a similar way to Octopus vulgaris. During this breeding period the female remains inside the shelter, taking care of the eggs. The species easily adapted to aquarium conditions, suggesting its suitability for rearing with either experimental or commercial purposes. Despite its importance for the fishing sector, the scarcity of studies focused on this species makes the information offered in the present work an important milestone in understanding the life cycle of E. cirrhosa in NW Iberian Peninsula, and, therefore, it represents a meaningful contribution to a comprehensive knowledge of the Iberian teuthofaunPeer reviewedUniversidade de AveiroGonzález, A. F.Consejo Superior de Investigaciones Científicas [https://ror.org/02gfc7t72]201720172017info:eu-repo/semantics/doctoralThesishttp://purl.org/coar/resource_type/c_db06http://hdl.handle.net/10261/157895reponame:DIGITAL.CSIC. Repositorio Institucional del CSICinstname:Consejo Superior de Investigaciones Científicas (CSIC)InglésSíinfo:eu-repo/semantics/openAccessoai:digital.csic.es:10261/1578952026-05-22T06:33:51Z
score 15,812429

Similar Items