∗ climate-y
+ management-y
Everyone loves an update
ATLANTIS MODELERS--WE SEE YOU
Brandon Beltz MS thesis Food web impacts of warming-driven migration shifts of top predators in the Mid-Atlantic Bight (MAB)
Shifts in migration range had more impact than shifts in migration timing
Non-prey species showed large changes in biomass in response to changes in predator migration. This suggests strong indirect effects are occurring and shows the more intricate ways that the food web can respond to change
Sarah Weisberg PhD thesis section/PopDy Fellowship Advancing Climate-Informed, Ecosystem-Based Fisheries Management Through Food Web Modeling, Indicator Development And Risk Analysis In The Rapidly Warming Gulf Of Maine
Ecological network analysis shows regimes in Gulf of Maine food web efficiency/resilience. Highly efficient food webs have lower resilience due to fewer trophic pathways decreasing redundancy.
The Gulf of Maine had low resilience in the 2000s, corresponding to poor fish condition
EBFM Objective 1: what happens with all the species in the region under a certain management regime?
EBFM Objective 2: how well do multispecies models perform for assessment?
MS-Keyrun model development and testing objectives are based on general ecosystem based management questions as well as specific discussions regarding EBFM development in New England. We will use this as an opportunity to address questions about the effects of management on the broader ecosystem, and about performance of assessment tools.
"Place-based" means a common spatial footprint based on ecological production, which contrasts with the current species-based management system of stock-defined spatial footprints that differ by stock and species.
The medium blue area in the map is Georges Bank as defined by NEFSC trawl survey strata. SOE = State of the Ecosystem report
The input data for this project differs from the input data for most current stock assessments, and the results of these multispecies assessments are not directly comparable with current single species assessments.
The project currently implements several place-based multispecies assessment models and one food web model. "Place-based" means a common spatial footprint based on ecological production, which contrasts with the current species-based management system of stock-defined spatial footprints that differ by stock and species. (See stock area comparisons.) Therefore, the input data for this project differs from the input data for most current stock assessments, and the results of these multispecies assessments are not directly comparable with current single species assessments. However, similar processes can be applied to evaluate these models. Georges Bank as defined for this project uses the NEFSC bottom trawl survey strata highlighted in medium blue below, which corresponds to the spatial unit for survey-derived ecosystem indicators in the Northeast Fisheries Science Center (NEFSC) New England State of the Ecosystem (SOE) report. Orange outlines indicate the ten minute square definitions for Ecological Production Units defined by a previous analysis.
(and eventually)
Fisheries Integrated Toolbox: MSSPM: https://nmfs-ecosystem-tools.github.io/MSSPM/
Hydra-Associated GitHub repositories
A common dataset for 10 Georges Bank species has been developed, as well as a simulated dataset for model performance testing. The mskeyrun
data package holds both datasets. All modeling teams used these datasets. Group decisions on data are also documented online.
Years: 1968-2019
Area: Georges Bank (previous map)
Species:
Atlantic cod (Gadus morhua),
Atlantic herring (Clupea harengus),
Atlantic mackerel (Scomber scombrus),
Goosefish (Lophius americanus),
Haddock (Melanogrammus aeglefinus),
Silver hake (Merluccius bilinearis),
Spiny dogfish (Squalus acanthias),
Winter flounder (Pseudopleuronectes americanus),
Winter skate (Leucoraja ocellata), and
Yellowtail flounder (Limanda ferruginea)
Simulated data from Norwegian Barents Sea Atlantis model via R package atlantisom
Norwegian-Barents Sea
For each model, reviews should evaluate:
Challenge of place based approach for stocks with substantial dynamics outside Georges Bank: "In that case, expanding the models outside the boundaries of the EPU, and/or explicitly accounting for the input/output of fish and energy across the boundaries will likely be needed"
Dedicated R packages for data positively reviewed
Standardize diet interactions and better quantify other food in estimation models using Rpath
Do model self-tests
Model specific structural and sensitivity recommendations
Self tests (4 species Hydra)
Model specific recommendations in progress
Testing in progress (next slides)
Work continues on input datasets
"Both our model predictions and the observations reside in a halo of uncertainty and the true state of the system is assumed to be unknown, but lie within the observational uncertainty (Fig. 1a). A model starts to have skill when the observational and predictive uncertainty halos overlap, in the ideal case the halos overlap completely (Fig. 1b). Thus, skill assessment requires a set of quantitative metrics and procedures for comparing model output with observational data in a manner appropriate to the particular application."
Stepwise development process of self fitting, fitting to atlantis output, then skill assessment using atlantis output
Profiles for estimated parameters; but what to compare K values to?
Can test model diagnostic tools as well
Using simulated data in
mskeyrun
package, available to all
MODELS SHOWN ARE EXAMPLE TRIAL FITS, NOT FINISHED OR GOOD MODELS
MODELS SHOWN ARE EXAMPLE TRIAL FITS, NOT FINISHED OR GOOD MODELS
MODELS SHOWN ARE EXAMPLE TRIAL FITS, NOT FINISHED OR GOOD MODELS
Do the same thing with Gadget, CEATTLE, Mizer, LeMans, Rpath... more participants welcome!
Simulated datasets have been added to mskeyrun
Discussion ongoing for planned comparisons
Gavin Fay, Lisa Kerr, Madeleine Guyant, Jerelle Jesse, Emily Liljestrand
Hydra: multispecies operating model conditioned on Georges Bank data within MSE framework as prototype test of EBFM strategies.
Results: additional flexibility and increased yield possible with EBFM "ceilings and floors" without increased risk to single stocks.
Caracappa, J. C. et al. (2022). "A northeast United States Atlantis marine ecosystem model with ocean reanalysis and ocean color forcing". En. In: Ecological Modelling 471, p. 110038. ISSN: 0304-3800. DOI: 10.1016/j.ecolmodel.2022.110038. URL: https://www.sciencedirect.com/science/article/pii/S030438002200148X (visited on Aug. 08, 2022).
Curti, K. L. et al. (2013a). "Evaluating the performance of a multispecies statistical catch-at-age model". En. In: Canadian Journal of Fisheries and Aquatic Sciences 70.3, pp. 470-484. ISSN: 0706-652X, 1205-7533. DOI: 10.1139/cjfas-2012-0229. URL: http://www.nrcresearchpress.com/doi/abs/10.1139/cjfas-2012-0229 (visited on Jan. 13, 2016).
Gaichas, S. K. et al. (2017a). "Combining stock, multispecies, and ecosystem level fishery objectives within an operational management procedure: simulations to start the conversation". In: ICES Journal of Marine Science 74.2, pp. 552-565. ISSN: 1054-3139. DOI: 10.1093/icesjms/fsw119. URL: https://academic.oup.com/icesjms/article/74/2/552/2669545/Combining-stock-multispecies-and-ecosystem-level (visited on Oct. 18, 2017).
Gamble, R. J. et al. (2009a). "Analyzing the tradeoffs among ecological and fishing effects on an example fish community: A multispecies (fisheries) production model". En. In: Ecological Modelling 220.19, pp. 2570-2582. ISSN: 03043800. DOI: 10.1016/j.ecolmodel.2009.06.022. URL: http://linkinghub.elsevier.com/retrieve/pii/S0304380009003998 (visited on Oct. 13, 2016).
Lucey, S. M. et al. (2021). "Evaluating fishery management strategies using an ecosystem model as an operating model". En. In: Fisheries Research 234, p. 105780. ISSN: 0165-7836. DOI: 10.1016/j.fishres.2020.105780. URL: http://www.sciencedirect.com/science/article/pii/S0165783620302976 (visited on Dec. 09, 2020).
Lucey, S. M. et al. (2020a). "Conducting reproducible ecosystem modeling using the open source mass balance model Rpath". En. In: Ecological Modelling 427, p. 109057. ISSN: 0304-3800. DOI: 10.1016/j.ecolmodel.2020.109057. URL: http://www.sciencedirect.com/science/article/pii/S0304380020301290 (visited on Apr. 27, 2020).
NRC (2007). "Chapter 4. Model Evaluation". En. In: Models in Environmental Regulatory Decision Making. Washington D.C.: The National Academies Press, pp. 104-169. DOI: 10.17226/11972. URL: https://www.nap.edu/read/11972/chapter/6 (visited on Aug. 29, 2019).
EBFM pMSE June 2023 New England Council
Slides available at https://noaa-edab.github.io/presentations
Contact: Sarah.Gaichas@noaa.gov
press "p" to see slide comments with even more equations
Species interactions:
Static model: For each group, i, specify:
Biomass B (or Ecotrophic Efficiency EE)
Population growth rate PB
Consumption rate QB
Diet composition DC
Fishery catch C
Biomass accumulation BA
Im/emigration IM and EM
Solving for EE (or B) for each group:
Bi(PB)i∗EEi+IMi+BAi=∑j[Bj(QB)j∗DCij]+EMi+Ci
Predation mortality M2ij=DCijQBjBjBi
Fishing mortality Fi=∑ng=1(Cig,land+Cig,disc)Bi
Other mortality M0i=PBi(1−EEi)
Dynamic model (with MSE capability):
dBidt=(1−Ai−Ui)∑jQ(Bi,Bj)−∑jQ(Bj,Bi)−M0iBi−CmBi Consumption:
Q(Bi,Bj)=Q∗ij(VijYpredjVij−1+(1−Sij)Ypredj+Si∑k(αkjYpredk))×(DijYpreyθijiDij−1+((1−Hij)Ypreyi+Hi∑k(βikYpreyk))θij)
Where Vij is vulnerability, Dij is “handling time” accounting for predator saturation, and Y is relative biomass which may be modified by a foraging time multiplier Ftime,
Y[pred|prey]j=FtimejBjB∗j
The parameters Sij and Hij are flags that control whether the predator density dependence Sij or prey density dependence Hij are affected solely by the biomass levels of the particular predator and prey, or whether a suite of other species’ biomasses in similar roles impact the relationship.
For the default value for Sij of 0 (off), the predator density dependence is only a function of that predator biomass and likewise for prey with the default value of 0 for Hij.
Values greater than 0 allow for a density-dependent effects to be affected by a weighted sum across all species for predators, and for prey. The weights αkj and βkj are normalized such that the sum for each functional response (i.e. ∑kαkj and ∑kβkj for the functional response between predator j and prey i) sum to 1. The weights are calculated from the density-independent search rates for each predator/prey pair, which is equal to 2Q∗ijVij/(Vij−1)B∗iB∗j.
Species interactions:
Based on Shaefer and Lotka-Volterra population dynamics and predation equations
dNidt=riNi(1−NiKG−∑gβigNgKG−∑GβiGNGKσ−KG)−Ni∑pαipNp−HiNi
Interaction coefficients αi,j can be positive or negative
C can be a Catch time series, an exploitation rate time series Bi,t∗Fi,t or an qE (catchability/Effort) time series.
Environmental covariates can be included on growth or carrying capacity (in the model forms that have an explicit carrying capacity).
Species interactions:
Based on standard structured stock assessment population dynamics equations, Same MSVPA predation equation as MSCAA (but length based), same dependencies and caveats
M2m,n,t=∑i∑jIi,j,tNi,j,tρi,j,m,n∑a∑bρi,j,a,bWa,bNa,b+Ω
But:
We specify 'preferred' predator-prey weight ratio (log scale) Ψj and variance in predator size preference σj to compare with the actual predator-prey weight ratio (wn/wj) to get the size preference ϑ.
ϑn,j=1(wn/wj)σj√2πe−[loge(wn/wj)−Ψj]2σ2j
Food intake is Ii,j,t=24[δjeωiT]ˉCi,j,k,t
Species interactions:
Based on standard age structured stock assessment population dynamics equations
M2i,a,t=1Ni,a,tWi,a,t∑j∑bCBj,bBj,b,tϕi,a,j,b,tϕj,b,t
Size preference is gi,a,j,b,t=exp[−12σ2i,j(lnWj,b,tWi,a,t−ηi,j)2]
Suitability, ν of prey i to predator j: νi,a,j,b,t=ρi,jgi,a,j,b,t
Scaled suitability: ˜νi,a,j,b,t=νi,a,j,b,t∑i∑aνi,a,j,b,t+νother
Suitable biomass of prey i to predator j: ϕi,a,j,b,t=˜νi,a,j,b,tBi,a,t
Available biomass of other food, where Bother is system biomass minus modeled species biomass: ϕother=˜νotherBother,t Total available prey biomass: ϕj,b,t=ϕother+∑i∑aϕi,a,j,b,t
∗ climate-y
+ management-y
Everyone loves an update
Keyboard shortcuts
↑, ←, Pg Up, k | Go to previous slide |
↓, →, Pg Dn, Space, j | Go to next slide |
Home | Go to first slide |
End | Go to last slide |
Number + Return | Go to specific slide |
b / m / f | Toggle blackout / mirrored / fullscreen mode |
c | Clone slideshow |
p | Toggle presenter mode |
t | Restart the presentation timer |
?, h | Toggle this help |
Esc | Back to slideshow |