Harvest of commercially exploited fish and shellfish Ecological Objective
Populations of selected commercially exploited fish and shellfish1
are within biologically safe limits, exhibiting a
population age and size distribution that is indicative of a healthy stock
Operational Objectives
Level of exploitation by commercial fisheries is within biologically safe limits
Indicators
Total catch by operational unit2 Total effort by operational unit Catch per unit effort (CPUE) by operational unit
The reproductive capacity of stocks is maintained
Ratio between catch and biomass index (hereinafter catch/biomass ratio). Fishing mortality Age structure determination (where feasible) Spawning Stock Biomass (SSB)
1. The choice of indicator species for collecting information for Ecological Objective 3 should be derived from fisheries targeting species listed in Annex III of Protocol concerning Specially Protected Areas and Biological Diversity in the Mediterranean (species whose exploitation is regulated) and the species in the GFCM Priority Species list (http://www.gfcm.org/gfcm/topic/166221/en). Choice of indicators should cover all trophic levels, and if possible, functional groups, using the species listed in Annex III of SPA and/or, as appropriate the stocks covered under regulation (EC) No 199/2008 of 25 February 2008 concerning the establishment of a Community framework for the collection, management and use of data in the fisheries sector and support for scientific advice regarding the Common Fisheries Policy 2. Operational unit is “the group of fishing vessels which are engaged in the same type of fishing operation within the same Geographical Sub-Area, targeting the same species or group of species and belonging to the same economic segment”
Marine food webs Ecological Objective
Alterations to components of marine food webs caused by resource extraction or human-induced environmen- tal changes do not have long-term adverse effects on food web dynamics and related viability
Operational Objectives
Ecosystem dynamics across all trophic levels are maintained at levels capable of ensuring long-term abundance of the species and the retention of their full reproductive capacity
Normal proportion and abundances of selected species at all trophic levels of the food web are maintained
Indicators
Production per unit biomass estimates for selected trophic groups and key species, for use in models predicting energy flows in food webs
Proportion of top predators by weight in the food webs
Trends in proportion or abundance of habitat-defining groups
Trends in proportion or abundance of taxa with fast turnover rates
Eutrophication Ecological Objective
Human-induced eutrophication is prevented, especially adverse effects thereof, such as losses in biodiversity, ecosystem degradation, harmful algal blooms and oxygen deficiency in bottom waters.
Operational Objectives
Human introduction of nutrients in the marine environ- ment is not conducive to eutrophication
Direct effects of nutrient over-enrichment are prevented
Indicators Concentration of key nutrients in the water column
Nutrient ratios (silica, nitrogen and phosphorus), where appropriate Chlorophyll-a concentration in the water column Water transparency where relevant
Number and location of major events of nuisance/toxic algal blooms caused by human activities1
Indirect effects of nutrient over-enrichment are prevented
Dissolved oxygen near the bottom, i.e. changes due to increased organic matter decomposition, and size of the area concerned2
1. The connection between eutrophication and toxic algal blooms is subject of devoted research at the moment. The connection between the two is not clearly established as not all the ecosystems react in the same way. In fact recent surveys in UK/Ireland in the framework of OSPAR have allowed concluding on the lack of relation between the them and therefore the number and location of major events of nuisance/toxic algal blooms should always be regarded cautiously as an indicator of a direct effect of nutrient over-enrichment. 2. Monitoring to be carried out where appropriate
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STATE OF THE MEDITERRANEAN MARINE AND COASTAL ENVIRONMENT