Stock Status

In our database, there are three main variables that describe stock status: percent of stocks at low risk of extinction, percent of stocks at moderate risk, and percent at high risk. It is difficult to present these three variables on a two-dimentional surface, such as a web map. For display purposes, we have assigned a relative level of risk to each ecoregion based on a variety of factors.

A relative risk was assigned to each stock by whichever percentage(low, moderate, high) contained a plurality. For example: in the Sacramento-San Joaquin Rivers ecoregion, you will find the following values for chinook:
High Risk: 24%
Moderate Risk: 29%
Low Risk: 47%

This ecoregion is assigned a 'Low Risk of Extinction' for chinook.

If the risk was split equally between two sequential gradations, (i.e. percent low and percent moderate risk were equal), other factors, such as total number of species extinct in that ecoregion, and estimated abundance, were factored in.

We encourage you to view the background data to get a better sense of the health of these stocks.