Biomass: Biomass

In nmfs-fish-tools/data_dictionary: Collaborative tool to improve consistency in terminology and develop a framework of tools for fisheries science.

Biomass

Description

Weight of fish within a stock. If referring to a certain portion of the stock, it should be made clear what portion of the stock the biomass pertains to. Model output related to biomass is assumed to be measured at the beginning of the year unless otherwise specified.

Usage

Biomass

Format

Examples

spawning biomass, age three-plus biomass, exploitable biomass, January 1 biomass

Rationale

Measurements of biomass should be better defined making it clear what year classes and sexes it includes. Historically, verbose labels, e.g., January 1 biomass of age-three plus fish in 2022, are not typically used; instead, labels are short, e.g., 2022 3+ biomass. Additional ambiguity can come from the lack of knowledge regarding the unit of measurement, which should always be metric tons. Some alternatives are not interchangeable because they are in different units, e.g., abundance, which is in terms of numbers rather than weight.

Alternatives

stock biomass, total biomass, abundance (numbers of fish), biomass wet weight, biomass index

Range of possible values

0–Inf

Units

mt

nmfs-fish-tools/data_dictionary documentation built on July 27, 2024, 12:20 p.m.