Model for spatial fishery planning and effort displacement

Questions this practice may help answer

• What is the ecological and economic impact of fishery management?
• How to evaluate the effects of smaller and larger marine area restrictions on stock and fisheries?
• What is the economic impact of spatial restrictions for the fishery?

Aspects / Objectives

DISPLACE combines several aspects:

• A bi-directional model. The DISPLACE model combines the fishing activity and resource dynamics with very high resolution in time, space and fishing units, which is rarely done although it is in literature recognized as necessary. That is, to take into account fish population responses to fishing and induced fishermen behavior, impacting on local scale and on single fishing operation level, in the assessment of various management actions.
• An individual-based model. There is a need to better encompass the connection between the micro-scale fishermen decisions and their economic causes and consequences at the macro-scale level (e.g. via the stocks and fish market dynamics) when evaluating the economic viability of the fishing sector and the sustainability of the marine ecosystems (stocks). In the DISPLACE model, vessels are simulated individually to visit their own specific grounds and ports at their own frequency which regenerates the individual fishing variability otherwise usually encapsulated into a regional aggregation.
• A supporting tool for impact assessement. DISPLACE wants to develop a collective understanding and a common discussion platform based on quantitative predictions of impacts and beneficial/detrimental effects on fishing activities of any new spatial marine planning project.

Thus, the objectives of the model is to provide input to:

• impact on economic returns from traditional fisheries;
• effect on MSFD indicators (e.g. spatial fishing pressure/footprint) and their economic value;
• impact assessment of Maritime Spatial Planning (MSP) on the fishery economy.

Method

The practice aims at implementating simulation models and tools for making integrated evaluation of impacts of different management options in fisheries under different environmental and climatic conditions (regimes), e.g. spatial planning:

• Biological impact on several stocks according to sustainable exploitation, MSY (multi-stock- level)
• Economic impact on several fisheries according to economic sustainability (profitability) and fleet reactions such as capacity changes and effort re-allocation (multi-fleet-level)
• Energy efficiency (and CO2 emission) in relation to spatial allocation of fisheries effort by fleet
• Ecosystem impact spatio-temporal fishing pressure on Benthic habitat and communities

DISPLACE operates with high resolution in time and space (a spatio-temporal explicit model). It allows contributing to marine spatial planning for evaluating the effects on stocks and fisheries (impact assessment on stocks and fisheries of marine management) and ultimately incorporating other utilization of the sea such as energy production, transport, recreational use, etc., e.g. offshore windmill farms, large marine constructions, NATURA 2000 areas, transport routes of commercial shipping, pipelines, cables, etc.

Main Outputs / Results

The model output provides stock biomasses and fishing mortalities for different exploitation patterns in space and time by different fleet components, and covers the full fishery system with technical interactions. This includes fishery pressures on the meso-pelagic community and fishery economic efficiency (cost, revenue, profit) as well as energy efficiency on vessel/fishery/ fleet basis.

• Fisheries biological output for use in sustainability analyses: Spatially (and temporal) resolved time series of exploited species biomass and fishing mortality, which can be evaluated according to sustainability targets (e.g. MSY) given landings/discards by multiple fisheries divided into fleets/metiers.
• Fisheries economic output for economic analyses in socio-economic and cross sector economic perspective: Revenue by species and commercial sorting of landings by vessel/fleet/ metier, fleet capacity dynamics, cost dynamics (fixed and variable costs – among other in relation to fuel), price dynamics (price-resource functions), and profit parameters for the different fleets and fisheries (metiers) as well as totally for the fishery on national (and cross national) basis.
• Fishery energy efficiency output: The model provides output on fuel and energy efficiency given different targeting and fishery effort allocation for vessels, fleets and fisheries (metiers).
• Fishery spatial anthropogenic pressure on seabed output: The model provides estimates of spatial fishing pressure (footprint in km2 of swept area, linked to the MSFD indicator) from the spatial application of various types of fishing gears and gear components from different gear widths, vessel engine powers, and penetration into the seabed. Fine time series of the spatial fishing pressure can be generated and aggregated (hourly to annual).

Transferability

The model is spatial explicit and can be adapted to whatever spatial and temporal scales relevant.

The DISPLACE model is transferable and has already been applied to several basins. The model first documented and implemented the dynamics of 16 commercially important fish stocks for the North Sea and Baltic Sea. This large-scale application was then followed by small-scale one dedicated to the Western Baltic Sea and a fish and fisheries DISPLACE application is currently being developed for the Northern Adriatic Sea.

Contact Person

Francois Bastardie,

DTU-Aqua, Denmark

fbaaqua.dtu.dk (fba[at]aqua[dot]dtu[dot]dk)

Responsible Entity

DTU-Aqua

Costs / Funding Source

Cost: Unknown

Funding Source: Partly financed by Seventh Framework Programme (FP7) – Research and Innovation programme for 2007-2013