Use this URL to cite or link to this record in EThOS:
Title: Sustainable fisheries and the diversity of marine communities : a theoretical investigation
Author: Fung, Tak Ching
Awarding Body: Queen's University Belfast
Current Institution: Queen's University Belfast
Date of Award: 2013
Availability of Full Text:
Full text unavailable from EThOS.
Please contact the current institution’s library for further details.
Effective implementation of an Ecosystem Approach to Fisheries Management (EA FM) is predicated upon scientific knowledge of how fishing affects biodiversity in large marine communities with > 1 ,000 species, and how changes in biodiversity translate into changes in marine ecosystem functioning. However, existing theoretical and experimental studies have both used systems with orders of magnitude fewer species. Thus, there is a critical need for research using larger, more species-rich systems. The presented thesis addresses this key knowledge gap by developing a unique model capable of producing large model temperate shelf communities each with > 1 ,000 dynamically interacting species. Shelf communities produced from this model are used in a diverse array of in silica experiments to quantify relationships between fishing, biodiversity and marine ecosystem functioning, hitherto unattempted. Firstly, a model community is subjected to 20 fishing scenarios to examine sensitivity of size diversity indicators to fishing and their recovery. Two central results are high sensitivity of size diversity to fishing intensity but not size-selectivity or duration, and slow decadal recovery times. Secondly, 12 different fishing scenarios corresponding to the Celtic and North Seas are applied to two model communities, to predict future recovery of size diversity in these two locations. Results show that for recovery to proposed target levels, fishing intensity must be maintained below mean historical values. Thirdly, a statistical population of 10 communities is used in experiments involving random or ordered deletion of fish species, to quantify relationships between fi sh species richness, two indicators of ecosystem functioning and three indicators of stability of functioning. With decreasing richness, functioning decreased according to a Michaelis-Menten or power-law function. On the other hand, stability increased or exhibited weak trends. Important mechanisms underlying outcomes from all simulations are elucidated. Results from this thesis have important practical implications for current and future implementations of an EAFM.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID:  DOI: Not available