Help Using Graphical Fish Database Browser

About the Graphical Fish Database Browser

The graphing software used for the Graphical Fish Database Browser was written using Java Applet technologies. To work on your computer, your Web browser must have java enabled. The graphing software displays data for the six LTRMP field stations at the same time. The user then can choose one of the six graphs to be displayed in more detail in the main window. The software also allows for printing and for creating a comma-delimited text document of the data that can be saved to the user's computer.

Using the Graphical Fish Database Browser

Above is a display of output from the graphing tool. The display is divided into two regions, the left column and the main window. In the left column, six small graphs (one for each field station) are displayed. The main window displays the active graph and its associated data table. To change the active graph, point the mouse arrow at the smaller version of the graph in the left column. This will highlight the chosen graph, displaying it in the main window. To see a numerical value on the graph in the main window, use the mouse to point to the location on the graph that you want to see the value for, or point to a specific year or value in the table. To print a graph, use the dialog box below the main window (shown here):

Select which graphs you wish to print by checking the small box to the left of each field station name. The default setting has all six boxes checked. Now click on the "Printer Friendly Page" button. The selected graphs will be displayed in a new window. Within this new window, click the print icon of your browser and the graphs will be printed, one per page. You may be able to print from the main window, but results are unpredictable depending on the browser and printer used. Another feature provided on the main window is the ability to create a comma-delimited text document by clicking the link below the printing information. This will open a new window containing a text document with header information followed by the data for all six field stations. You will have to save this page by clicking the "file" menu followed by "save as". Give the file a name and location to be saved then change the file type from .html to .txt and click "save". You can import the comma-delimited text file into other applications for custom graphing or statistical analysis.

Enabling Java in Netscape and Internet Explorer

Internet Explorer

1. Click "Tools"
2. Click "Internet Options"
3. Click "Advanced"
4. Check the check boxes under the Java category

Netscape Navigator

1. Click "Edit"
2. Click "Preferences"
3. Click the "Advanced" option
4. Click the "Enable Java" option

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Help With Gears

• Electrofishing
• Hoop nets
• Seines
• Fyke nets
• Bottom trawl

Electrofishing (Day and Night)
	Standardized electrofishing is conducted in aquatic areas where depth ranges from approximately 0.5 to 3.0 m using pulsed DC current. The standard unit of electrofishing effort is time (per 15 minutes of effort). Electrofishing is the least size selective gear used in the LTRMP. For more information on electrofishing, see the LTRMP Fish Monitoring Procedures document.

Hoop Nets (Large and Small)
	The LTRMP deploys small and large baited hoop nets fished in a paired configuration. The standard unit of hoop netting effort is the net-day, where days are 24 hours and each hoop net within a pair counts as one net. Hoop nets are generally selective for medium to large body species and size classes. For more information on hoop netting, see the LTRMP Fish Monitoring Procedures document.

Seines
Seines are fished in shallow shoreline habitat. The standard unit of seining effort is the net-haul. Seines are generally selective for small species and size classes of fish. For more information on seining, see the LTRMP Fish Monitoring Procedures document.

Fyke Nets

Fyke nets are deployed in a variety of habitats. The standard unit of effort for fyke nets is the net-day (24 hours). Fyke nets are generally selective for medium-sized species. For more information on fyke nets, see the LTRMP Fish Monitoring Procedures document. Mini Fyke Nets Mini fyke nets are deployed in a variety of habitats. The standard unit of effort for mini fyke nets is the net-day (24 hours). For more information on mini fyke netting, see the LTRMP Fish Monitoring Procedures document. Tandem Fyke Nets In offshore impounded or backwater sites, two fyke nets are fished end-to-end (tandem set), with the leads tied together. The fyke nets are anchored at both ends in low velocity, shallow water habitat. The end-to-end fyke net sets require a different gear code than traditional sets. For more information on tandem fyke netting, see the LTRMP Fish Monitoring Procedures document. Tandem Mini Fyke Nets Tandem mini fyke nets are same as tandem fyke nets except they use two mini fyke nets instead of two regular fyke nets.

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Help With Strata

• Main Channel Border-Unstructured
• Main Channel Border-Wing Dam
• Side Channel Border
• Backwater Contiguous-Open Water
• Backwater, Contiguous-Nearshore
• Impounded-Open Water
• Impounded-Nearshore
• All

The LTRMP stratifies fish sampling across eight strata, characterized by enduring geomorphic and physical features(Wilcox 1993). The LTRMP fish sampling strata are defined as follows:

Main Channel Border-Unstructured

Aquatic areas between the margins of the main navigation channel and the nearest shoreline (island or mainland) excluding dams, lock walls, and wing dams.

Main Channel Border-Wing Dam

A localized portion of main navigation channel border in which a wing dam is the predominant physical feature. Wing dams are artificial structures that restrict flow to the navigation channel and are usually constructed of rock. Wing dams protrude from the shoreline and may be submerged or emergent. Fish sampling by the LTRMP is restricted to wing dams that are at least 50 m long. In addition, because of hydraulic conditions, wing dams submerged under more than 2 m of water are not sampled, and wing dams submerged under 1-2 m of water may not be sampled if current velocity over the top exceeds 0.5 m/s.

Side Channel Border

This stratum is characterized by secondary and tertiary channel borders that have terrestrial margins and measurable current velocities at normal water elevations. For the purpose of LTRMP fish sampling, fully submerged secondary or tertiary channels that do not have terrestrial margins (such as may occur in impounded areas above dams) are not considered side channels. Shallow narrow side channels may not have a well defined trough or thalweg, in which instance the borders extend to mid-channel.

Backwater Contiguous-Open Water

Backwater contiguous-open water is characterized by having some connection by water to the main navigation channel but are separated from the main channel by a terrestrial area and do not carry flow at normal river elevations. Backwaters may consist of floodplain depression lakes, sloughs, lateral levee lakes, bays, and artificial lacustrine areas. Offshore areas are more than 50 m from the nearest shoreline. Small backwaters may not have an offshore area.

Backwater Contiguous-Nearshore

Backwater contiguous-nearshore is characterized by areas of contiguous backwaters that are within 50 m of the nearest shoreline.

Impounded-Open Water

Impounded areas are large, mostly open-water areas located immediately upriver from locks and dams. Water elevations are held above pre-impoundment levels by the dams. Impounded areas may contain submerged channels and areas that were terrestrial before impoundment. An offshore area is more than 50 m from the nearest shoreline.

Impounded-Nearshore

Impounded-nearshore areas are those portions of impounded areas within 50 m of the nearest shoreline.

All

Within the Graphical Fish Database Browser, strata listed above represent a spatially defined area of a study reach that is smaller than the study reach itself. Estimates from each of the individual strata listed above are "pooled" and appropriate "weighting factors" are applied to derive an unbiased estimate for the entire study reach from the collection of strata-specific estimates. Thus, the ALL stratum represents an unbiased estimate at the study reach scale, which is larger in physical size than the individual strata.

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Help With Metrics

• Catch Per Unit of Effort
• Proportional Stock Density
• Frequency of Occurrence
• Species List
• Community Composition
• Species Richness

Catch Per Unit of Effort

A measure of a species relative abundance based on the standard unit of effort for each gear. Catch per unit of effort metrics are calculated from random samples that provide an unbiased measure of relative abundance.

Proportional Stock Density

Proportional stock density is a measure of species size structure. The metric is the percentage of quality-sized individuals within the total number of stock-sized individuals. Stock and quality size designations vary by species. Proportional Stock Densities are presented for 14 commercially and recreationally exploited species.

Frequency of Occurrence

A measure of species ubiquity calculated as the percentage of LTRMP samples containing at least one individual of any given species.

Species List

Species list is an alphabetical list of species collected over all LTRMP monitoring efforts, since 1993.

Community Composition

An alphabetical table portraying species present in each of the study areas.

Species Richness

A measure of the diversity within each study area expressed as the total number of species observed each year.

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