21 research outputs found
Behavioural responses to unexpected changes in reward quality
Successive negative contrast (SNC) effects are changes in anticipatory or consummatory behaviour
when animals unexpectedly receive a lower value reward than they have received previously. SNC
effects are often assumed to reflect frustration and appear to be influenced by background affective
state. However, alternative explanations of SNC, such as the functional-search hypothesis, do not
necessarily imply an aversive affective state. We tested 18 dogs in a SNC paradigm using a patch
foraging task. Dogs were tested in two conditions, once with the low value reward in all of five trials
(unshifted) and once when reward value was altered between high and low (shifted). Following a
reward downshift, subjects showed a SNC effect by switching significantly more often between
patches compared to the unshifted condition. However, approach latency, foraging time and quantity
consumed did not differ between conditions, suggesting non-affective functional search behaviour
rather than frustration. There was no relationship between strength of SNC and anxiety-related
behaviours as measured in a novel object test and a personality questionnaire (C-BARQ). However,
associations with the C-BARQ scores for Trainability and Stranger directed aggression suggest a
possible link with behavioural flexibility and coping style. While reward quality clearly affects incentive
motivation, the relationship between SNC, frustration and background affective state requires further
exploration
Some reflections on U.S. public opinion surveys in post-war Germany
SIGLEUuStB Koeln(38)-860106029 / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman
World Octopus Fisheries
153 pages, 97 figures, 10 tables, 2 appendixesRecent studies have shown that coastal and shelf cephalopod populations have increased globally over the last six decades. Although cephalopod landings are dominated by the squid fishery, which represents nearly 80% of the worldwide cephalopod catches, octopuses and cuttlefishes represent ∼10% each. Total reported global production of octopuses over the past three decades indicates a relatively steady increase in catch, almost doubling from 179,042 t in 1980 to 355,239 t in 2014. Octopus fisheries are likely to continue to grow in importance and magnitude as many finfish stocks are either fully or over-exploited. More than twenty described octopus species are harvested from some 90 countries worldwide. The current review describes the major octopus fisheries around the globe, providing an overview of species targeted, ecological and biological features of exploited stocks, catches and the key aspects of managementIGG has been supported by the Japan Science and Technology Agency (Grants J130000263 and AS2715164U). RV has been supported by the Spanish Ministry of Education and Culture (Grant PRX17/00090), Spanish Ministry of Science, Innovation and Universities (OCTOSET project, RTI2018-097908-B-I00, MCIU/AEI/FEDER, EU) and by the Direcció General de Pesca i Afers Marítims, Generalitat de Catalunya. FAFA was supported by a predoctoral fellowship of the MINECO (BES-2013-063551) and an Irish Research Council - Government of Ireland Postdoctoral Fellowship (Ref. GOIPD/2019/460)Peer reviewe
Not Available
Not AvailableRecent studies have shown that coastal and shelf cephalopod populations have increased globally over the last six decades. Although cephalopod landings are dominated by the squid fishery, which represents nearly 80% of the worldwide cephalopod catches, octopuses and cuttlefishes represent ∼10% each. Total reported global production of octopuses over the past three decades indicates a relatively steady increase in catch, almost doubling from 179,042 t in 1980 to 355,239 t in 2014. Octopus fisheries are likely to continue to grow in importance and magnitude as many finfish stocks are either fully or over-exploited. More than twenty described octopus species are harvested from some 90 countries worldwide. The current review describes the major octopus fisheries around the globe, providing an overview of species targeted, ecological and biological features of exploited stocks, catches and the key aspects of management.Not Availabl
World Octopus Fisheries
Recent studies have shown that coastal and shelf cephalopod populations have increased globally over the last six decades. Although cephalopod landings are dominated by the squid fishery, which represents nearly 80% of the worldwide cephalopod catches, octopuses and cuttlefishes represent ∼10% each. Total reported global production of octopuses over the past three decades indicates a relatively steady increase in catch, almost doubling from 179,042 t in 1980 to 355,239 t in 2014. Octopus fisheries are likely to continue to grow in importance and magnitude as many finfish stocks are either fully or over-exploited. More than twenty described octopus species are harvested from some 90 countries worldwide. The current review describes the major octopus fisheries around the globe, providing an overview of species targeted, ecological and biological features of exploited stocks, catches and the key aspects of management