The National Fish Habitat Action Plan map and data viewer has been created to facilitate broad access to the analysis results reported in the
first "Status of Fish Habitats in the United States" report. The ability to visualize these results in an applied format widely available to
stakeholders can truly enhance collaborative and coordinated efforts that support conservation and management of fish habitats.
Visualizing the results at multiple spatial scales allows for application at multiple management and policy levels and is critical for
strategic decision-making that can help maximize our collective effectiveness of fish habitat conservation efforts across the United States.
The results of the assessment are characterized as risk of current habitat degradation, i.e., for any particular area the data suggest
some level of risk (high, low, or in between) that the habitat is currently in a degraded condition. The assessment uses risk of habitat
degradation instead of known habitat degradation because habitat condition has not been objectively or consistently measured for a
majority of aquatic habitats in the United States. As a result, the assessments for this report focus on identifying factors that
are responsible for degrading habitat, rather than using direct measurements of habitat condition.
Although a large amount of data went into the assessments, some key information is missing due to the lack of nationally consistent
data. Examples of missing information include historical and regional degradation due to logging, mining, or animal farming, the effect
of water pumped or otherwise diverted from streams, and dams less than six feet high that fragment streams and obstruct fish passage.
Because this information is missing, areas mapped as having a low risk of current habitat degradation due to the factors assessed may
be under the influence of factors not included in the assessment, and thus actually may be at a higher risk of current habitat degradation
than depicted on the maps.
Users should interpret the maps carefully. The maps should not be understood as depicting absolute habitat condition. They do serve
as a guide to the relative magnitude and geographic distribution of many factors that contribute to aquatic habitat degradation. Varied
methodologies were used for assessing the rivers of the lower 48 States, the rivers of Alaska and Hawaii, the estuaries of the lower 48
States, and the estuaries of Southeast Alaska. Summarized methodologies are briefly noted in the information window that is displayed in
the map viewer and more detailed explanations of the methodologies can be found in the report. The map viewer enables fish habitat
condition scores to be displayed at multiple geographic scales for the various regions of the United States. For spatial units
that may be unavailable for a particular region, the map is shaded gray. When those areas are selected, available spatial units are suggested.
The tools that have been developed are intended to provide information to aid decisions and facilitate collaborative efforts among partners and stakeholders. Comments and recommendations for improvements are welcomed.