Surplus Production Models (SPM) - What they are and how to calculate - Fisheries Stock Assessment

This video provides a detailed explanation of what surplus production models (SDMs) are, when they are used and the data requirements, including how to reach estimates of biological parameters including r (growth rate), k (carrying capacity) and initial biomass.
The equations of the model are broken down step by step and 'translated' into simple to understand R code. Model outputs are explained and how to interpret the resulting graphs in the context of other available data.
The production function from the Schaefer (1954, 1957) model is used, however details of how and when to use other production functions such as Fox (1970) and Pella and Tomlinson (1969) are provided in the linked videos.
The yellowfin tuna (Thunnus albacares) longline fishery in the Indian Ocean is used as an example of how surplus production can be calculated - data downloaded from the Indian Ocean Tuna Commission: iotc.org/TCAC/12/data/01-esti...
Music Sources
Onceagain, bensound.com
JuliusH, Calm waves, pixabay.com

[@Sumroz1]

Your videos regarding fisheries are amazing and full of knowledge, keep growing

[@oceans_explained]

Thank you! I'm glad they are helpful :)

[@williamvickery]

Wow, thank you this is such a good explanation!

[@oceans_explained]

Thanks, glad I could help!

[@alexanderrosen7233]

I really like your videos and great channel :), any idea when the next one is coming out?