6 research outputs found
Fisheries Centre research reports. Volume 12, number 5
No full textDIRECTOR’S FOREWORD (Daniel Pauly). FOREWORD (Sarah Chasis and Karen Garrison). EXECUTIVE SUMMARY (Daniel Pauly). INFERENCES OF POTENTIAL SEAMOUNT LOCATIONS FROM MID-RESOLUTION BATHYMETRIC DATA (Adrian Kitchingman and Sherman Lai). Appendix 1. 1. Location of > 14,000 likely seamounts. SEAMOUNTSONLINE: AN ONLINE RESOURCE FOR DATA ON THE BIODIVERSITY OF SEAMOUNTS (Karen Stocks). SEAMOUNT INVERTEBRATES: COMPOSITION AND VULNERABILITY TO FISHING (Karen Stocks). Appendices 1a-1d: Data in invertebrates collected from seamounts globally. 1a. List of species from seamounts - ordered by species. 1b. List of species from seamounts - ordered by seamount. 1c. Bibliography of data sources cited in appendices 1a and 1b. 1d. Distribution maps for seamount invertebrates given in appendices 1a and 1b. TAXONOMY AND BIOLOGY OF SEAMOUNT FISHES (Rainer Froese and Arlene Sampang). Appendices 1-6. 1. Preliminary annotated checklist of seamount fishes.
2. Preliminary list of seamount fishes with reported seamounts. 3. Preliminary checklist of fishes by seamount.
4. Preliminary list of commercially important seamount fishes. 5. Reference numbers with citations. 6. Preliminary bibliography of seamount fishes.
A FUZZY LOGIC EXPERT SYSTEM FOR ESTIMATING THE INTRINSIC EXTINCTION VULNERABILITIES OF SEAMOUNT FISHES TO FISHING
(William W. L. Cheung, Tony J. Pitcher and Daniel Pauly). Appendix 1. 1. Assignment of strength of spatial behaviour of fish onto a 1 to 100 arbitrary scale. VULNERABILITY OF SEAMOUNT FISH TO FISHING: FUZZY ANALYSIS OF LIFE HISTORY ATTRIBUTES (Telmo Morato, William W. L. Cheung and Tony J. Pitcher). Appendix 1. 1. Additions to Froese and Sampang’s checklist of seamount fishes. EXPLOITATION PATTERNS IN SEAMOUNT FISHERIES: A PRELIMINARY ANALYSIS (Reg Watson and Telmo Morato). Appendix 1. 1. Commercial fish taxa associated with seamounts. MANAGING AND PROTECTING SEAMOUNT ECOSYSTEMS (Jackie Alder and Louisa Wood). GLOSSARY.Oceans and Fisheries, Institute for theScience, Faculty ofUnreviewedFacultyResearcherGraduat
Deep-Sea ecosystem model of the Condor seamount
No full textDissertação de Mestrado, Estudos Integrados dos Oceanos, 25 de Julho 2013, Universidade dos Açores.Seamounts play an important role in the status of food webs and biodiversity in the open ocean. These habitats are now subject to an intensive exploitation and it is urgent to apply an ecosystem perspective towards the development of sustainable fisheries. Ecosystem models offer scope to understand the interactions between fisheries, exploited species and the ecosystem that supports them, enabling impact assessments of human activities on the marine environment. This study describes the construction and input data of an Ecopath with Ecosim model for the Condor seamount ecosystem, located in the Azorean archipelago (NE Atlantic). The model comprises 23 functional groups, including plankton, invertebrates, fishes, marine mammals and seabirds. The fisheries component consists on the regional fleet, with an emphasis on demersal fisheries. This model can serve as a basis for future Ecosim and Ecospace simulations of the effect of fishing on Condor seamount or on other seamounts around the Azorean islands
Habitat predictive modelling of demersal fish species in the Azores
No full textDissertação de Mestrado, Estudos Integrados dos Oceanos, 25 de Março de 2013, Universidade dos Açores.Species distribution modelling of the marine environment has been extensively used to assess species–environment relationships to predict fish spatial distributions accurately. In this study we explored the application of two distinct modelling techniques, maximum entropy model (MaxEnt) and generalized linear models (GLMs) for predicting the potential distribution in the Azores economic exclusive zone (EEZ) of four economically important demersal fish species: blackbelly rosefish, Helicolenus dactylopterus dactylopterus, forkbeard, Phycis phycis, wreckfish, Polyprion americanus and offshore rockfish, Pontinus kuhlii. Models were constructed based on 13 years of fish presence/absence data derived from bottom longline surveys performed in the study area combined with high resolution (300 m) topographic and biogeochemical habitat seafloor variables. The most important predictors were depth and slope followed by sediment type, oxygen saturation and salinity, with relative contributions being similar among species. GLMs provided ‘outstanding’ model predictions (AUC>0.9) for two of the four fish species while MaxEnt provided ‘excellent’ model predictions (AUC=0.8–0.9) for three of four species. The level of agreement between observed and predicted presence/absence sites for both modelling techniques was ‘moderate’ (K=0.4–0.6) for three of the four species with P. americanus models presenting the lowest level of agreement (K<0.1). For the scope of this study, both modelling approaches presented here were determined to produce viable presence/absence maps which represent a snap–shot of the potential distributions of the investigated species. This information provides a better description of demersal fish spatial ecology and can be of a great deal of interest for future fisheries management and conservation planning
Mapping deep-sea biodiversity and good environmental status in the Azores: assisng with the implementaon of EU Marine Strategy Framework Direcve
No full textTese de Doutoramento, Ciências Biológicas, 26 de junho de 2023, Universidade dos Açores.ABSTRACT: One of the major shortfall of biodiversity knowledge steams from an incomplete description of the geographical distribution of species. Overcoming this shortfall is essential for conserving nature and its services and it is a required first step to tackle more complex ecological processes (e.g. dispersal, speciation, disturbance, biotic interactions, etc.) in remote and poorly studied regions such as the deep sea. In a region such as the Azores (NE Atlantic), where the deep sea represents a dominant component of the seascape, it is essential to characterize patterns and processes of deep-sea biodiversity. In fact, only by understanding how species and marine resources distribute it is possible to correctly inform area- and ecosystem-based management and achieve the goals of policies aiming at reversing the cycle of decline in ocean health. In particular, the European Commission has adopted a number of policies to grant a sustainable use of nature space and resources which include the Marine Strategy Framework Directive (MFSD) and the Maritime Spatial Planning Directive (MSPD). The overall goal of this thesis is to bring together existing and new biodiversity data from recent scientific surveys to deepen our understanding of biodiversity and biogeographic patterns of deep-sea Vulnerable Marine Ecosystems (VMEs) indicator taxa. The focus is on deep-sea hard-substrate communities of the Azores and, in particular, on ecosystem engineer species of the Phyla Cnidaria and Porifera. Four major environmental drivers of deep-sea benthic engineer species are recognized in the Azores: (i) a latitudinal gradient in primary production strongly influenced by the Azores Current-Azores Front (AzC-AzF) system; (ii) the depth-wise succession of the regional water masses and their stratification into different isopycnal (vertical) layers; (iii) the spatial distribution of prominent geomorphic features such as seamounts ridges and island slopes; (iv) the availability of hard substrate for attachment. The recognition of these environmental drivers sets an interesting background for future ecological research, ecosystem-based management and spatial monitoring. The response of deep-sea species to these environmental drivers is explored in detail in the different chapters of the present manuscript
Ecology and fisheries of seamount ecosystems
No full textThis thesis explores some fundamental questions about seamount ecology and fisheries. Initially, I characterized the seamount distribution on the Azores Exclusive Economic Zone using two bathymetry datasets. The algorithm developed was able to map and describe 63 large and 332 small seamount-like features in the EEZ of the Azores. The distribution suggests that large proportion of seamounts occur in chains along the Mid Atlantic Ridge, however, few isolated seamounts are also present in the Azores. In clarifying how seamounts affect primary productivity, I show that primary production enhancement is not sufficient to support often-observed large aggregations of fish. My work supports an alternative hypothesis, that a horizontal flux of prey is the key factor in sustaining rich communities living on seamounts. Additionally, the importance of seamounts to some large pelagic fish, marine mammals and seabirds is also demonstrated. In the case of skipjack and bigeye tuna, common dolphin and Cory's shearwater, these species were significantly more abundant in the vicinity of some seamount summits. I found that seamounts may act as feeding stations for some of these visitors. The methodology developed, however, failed to demonstrate seamounts' association for bottlenose dolphins, spotted dolphin, sperm whale, terns, yellow-legged gull, and loggerhead sea turtles. Fisheries exploitation is a major threat to seamount ecosystems, but I am not presently able to quantify the amount of catches taken from seamounts around the world. Instead, 1 demonstrate that global landings of demersal marine fishes have shifted to deeper water species over the last 50 years, an indirect indication that seamounts have also increased in importance. Moreover, I show that 'deep-water', 'seamount' and 'seamount-aggregating' fish stocks may be at serious risk of depletion, since their life histories render them highly vulnerable to overfishing with little resilience to overexploitation. Finally, ecosystem modelling analyses indicate that sustainable seamount fisheries with tolerable ecosystem impacts can be found only by maximizing an 'ecological' objective function. This suggests that industrial fisheries are not viable on seamounts. However, regulated small-scale artisanal fishing fleets could be sustained by seamount ecosystems.Science, Faculty ofResources, Environment and Sustainability (IRES), Institute forGraduat
Anthropogenic impacts in the deep sea of the Azores : fishing and litter
No full textTese de Doutoramento em Ciências do Mar, especialidade em Ecologia Marinha.[...]. Os objetivos deste trabalho são, essencialmente, os de caracterizar e entender duas ameaças importantes para o mar profundo dos Açores: a pesca e o lixo. [...]. De um modo geral, este trabalho sugere que a gestão sustentável dos recursos do oceânico profundo deve incluir todos os efeitos das atividades humanas. No caso particular dos Açores, a gestão dos recursos vivos marinhos, se baseada no funcionamento dos ecossistemas, deve ter em consideração as rejeições da pesca, os danos induzidos pela pesca aos habitats bentónicos e a acumulação de lixo.ABSTRACT: [...]. The objectives of this work are to further characterize and understand two important threats for deep sea ecosystem off the Azores; fishing and litter disposal. [...]. My thesis work suggests that sustainable management of deep-sea resources must include all likely effects of human activities. Ecosystem-based management of the deep-sea in the Azores needs to address fisheries discards, damages to benthic habitats, and litter disposal.This research was funded by the the Fundação para a Ciência e a Tecnologia (FCT, Grant number (SFRH/BD/31286/2009) and conducted in the framework of the EU FP7 projects CoralFISH (FP7 ENV/2007/1/21314 4) and HERMIONE (FP7 ENV/ 2008/1/226354
