This animation displays changes in estimated brown trout numbers by life stage through time for a section of river based on depth and velocity habitat suitability criteria. This two-dimensional view shows cell-by-cell distribution of the estimated fish population in patches of suitable habitat for that time period.
The top of the screen (shown below) reveals the week and the date on the left and the corresponding flow in the river, measured in cubic feet per second (cfs), on the right.
In the screen below are six panels that depict the estimated depth and velocity suitability on the left and the estimated, weighted usable area on the right for each study unit of the river. The top two panels present the egg/alevin life stage, the middle two panels the fry life stage, and the bottom two panels the fingerling life stage.
River study units are separated by a line perpendicular to the flow at that point and classified by distinct habitat type.
The color legend along the bottom provides an index to the estimated depth and velocity suitability and the corresponding weighted usable area for each life stage shown. As the weeks progress and flows change, color appears, changes, and disappears in the river study units, indicating the estimated numbers of individuals present. The river segment gets larger and smaller, and side channels open and close, corresponding to the changes in flow. Over the one-year duration seen in this animation, estimated populations of brown trout eggs/alevins mature into fry and fry grow into fingerlings.
To view this animation, select a link below (Note: animations are in WMV format and will open automatically in Windows Media Player).
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