In Blue-Matter/MERA: Method Evaluation and Risk Assessment

How to use MERA

MERA has two inputs: a mandatory quantitative questionnaire and optionally, a standardized format for fishery data (Figure r paste(SecInd,FigInd+1,sep=".")). The questionnaire contains a total of 30 questions, 19 regarding the fishery dynamics, 7 questions about the management system and a further 4 about the types and quality of data that are available (see Section 2 for details on all questions).

MERA has three principal modes that reflect the ways in which MERA can be used to inform management:

1. Management Planning – determining a suitable management mode

2. Management Performance – evaluating current management mode

3. Status Determination – calculating stock status.

The first two use the quantitative questionnaire and (optionally) data to construct an operating model. If compatible data are loaded, the operating model will be automatically conditioned on those data.

The status determination mode requires additional user data to estimate stock status.

Where operating model features are required that are not included in the quantitative questionnaire it may be exported into the R statistical environment, modified and imported back into the MERA software. The three R packages that come under the openMSE umbrella are DLMtool (Carruthers and Hordyk 2018) and MSEtool (Hordyk et al. 2021) and SAMtool (Huynh et al. 2021). These are compatible with MERA operating models and data files and include a wide range of tools for modifying these to include custom dynamics such as ontogenetic habitat shifts, fine-scale movement dynamics, time varying movement, temporal changes in growth and natural mortality rate, shifting fleet size selectivity and economic constraints.

FigInd<-FigInd+1

Figure r paste(SecInd,FigInd,sep="."). MERA components and workflow.

A note on skins

MERA includes considerable flexibility on how results of the three use-cases are presented. This is to allow various user groups to obtain results that are pertinent to their application and setting.

For the purpose of this documentation results are presented for the Marine Stewardship Council skin.

Blue-Matter/MERA documentation built on March 17, 2023, 3:02 p.m.