GEM – Geochemical and Ecological Modelling Carrying Capacity as an Ecosystem Management tool,

GEM – Geochemical and Ecological Modelling Hydrodynamic model – simulates the circulation and phytoplankton productivity. Used to generate water exchange and boundary conditions to implement ecological models Shellfish model – Growth predicted by ShellSIM of individual shellfish species is used in the EcoWIN ecological model to simulate the population dynamics of cultivated oysters and mussels EcoWIN2000(E2K) is an ecological model that provides a platform for integration of the other models and adds functionality of its own. Runs for multi-year periods

GEM – Geochemical and Ecological Modelling Modelling framework Run Delft 3D for large domain (Western Irish Sea and four loughs) using a fine grid (each lough has hundreds of cells) Define larger boxes (<50) within the loughs with GIS for E2K using (I) current and bathymetry data (ii) WFD (iii) aquaculture distribution Use D3D to calculate water fluxes across these larger boxes at 30m intervals, and at the seaward boundary of the lough domain – supply these offline as spreadsheets Hydrodynamic transport simulated in E2K by reading these spreadsheet files during an E2K model run Prepare a water quality database including both the individual lough and inputs from freshwater and ocean boundaries (measurements) Enter larger box areas, volumes etc from GIS into E2K Run full E2K model, calibrate and validate Simulate individual shellfish physiology using a raceway model Use results to conceptualise an energy budget model for individual growth Implement and validate individual growth model in Stella or other simple modelling package Measure individual shellfish growth rates in the field Implement individual growth model in E2K, test, and then add population dynamics Extract E2K initial conditions for state variables in each box, boundary conditions and calibration data Delft3D EcoWin2000 ShellSim2006 Management scenarios

GEM – Geochemical and Ecological Modelling

GEM – Geochemical and Ecological Modelling

GEM – Geochemical and Ecological Modelling

GEM – Geochemical and Ecological Modelling SMILE is an ecosystem model, a series of interconnected boxes 34 boxes, 2 layers Criteria for boxes: Water framework Directive Topography Biogeochemistry

GEM – Geochemical and Ecological Modelling Strangford Lough 340 boxes 8  layers 34 boxes 2 σ layers EcoWin2000 ecological model A much coarser grid is used in biogeochemical models than in hydrodynamic models. Delft3D Hydrodynamic model

GEM – Geochemical and Ecological Modelling So far! Developed growth models for Modiolus modiolus, Ostrea edulis and Pecten maximus in addition to existing species Growth models integrated into software to check that individual growth can be accurately scaled up for ecosystem models SMILE model framework changed to deal with three new species Now in position to simulate growth in certain areas at varying densities

GEM – Geochemical and Ecological Modelling Objectives Examine growth of Modiolus Simulate growth Investigate growth at varying stocking densities for Modiolus Determine optimal locations for restoration Examine knock-on effects

GEM – Geochemical and Ecological Modelling ShellSIM – simulation of shellfish growth Real time feeding experiments required to measure Modiolus feeding rates. Experiments show how temp and food availability effect feeding. Allowing us to model how changes in the lough (or different areas) will effect Modiolus feeding and hence growth With the addition of population dynamics to the individual model, shellfish stocks can be modelled over mutil-year periods (E2K)

GEM – Geochemical and Ecological Modelling Simulated temperature, illustrating northern and southern trends. Matches well with measured values.

GEM – Geochemical and Ecological Modelling Simulated temperature graph Year 1Year 2

GEM – Geochemical and Ecological Modelling J F M A M J J A S O N D Strangford Lough Box 22 - Lough entrance Phytoplankton (µg Chla l -1 ) SPM (mg l -1 ) POM (mg l -1 ) DIN (µmol l -1 ) J F M A M J J A S O N D

GEM – Geochemical and Ecological Modelling Simulated growth curve for Pecten maximus

GEM – Geochemical and Ecological Modelling M. modiolus growth

GEM – Geochemical and Ecological Modelling Modiolus individual growth size refuge/ sexual maturity match to measured growth, 10y mean length of 7cm Year 5Year 10

GEM – Geochemical and Ecological Modelling Possible factors NB. Important to remember, only modelling Mytilus, Crassostrea and Modiolus at present, need to turn on wild species and additional aquaculture species

GEM – Geochemical and Ecological Modelling Food does not seem to be limiting! Other factors, including: Suitable habitat Predation pressure Brood stock availability…..

GEM – Geochemical and Ecological Modelling Next step Integrate Wild species Turn on new Aquaculture species Invite scenarios

GEM – Geochemical and Ecological Modelling

GEM – Geochemical and Ecological Modelling Operate at Eunis level three or four; Rather than worrying about individual species use broadscale habitat layers; Assign loss rates or or “feeding” rates based on top five keystone species; Each habitat will be assigned a feeding type – i.e deposit, suspension feeder;