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| NAS - Nonindigenous Aquatic Species |
This map layer is a compilation of confirmed
northern snakehead sighting reports in the United States 1997 through 2009 and is updated daily.
It provides geographical and historical information to show distribution
over space and time. The reports came primarily from State agencies in the region. The locations of confirmed sightings were registered at 1:100,000-scale on EPA Reach File Version 3.0 and are
maintained as an ArcInfo shapefile. These data are intended for geographic display and analysis at the
national level, and for large regional areas. Sightings were reported with varying levels of accuracy.
Some of the reports were as latitude-longitude coordinates, some as
river miles, and others as just a lake, beach, harbor, or a
water body and nearest town name. If no specific location was reported in a lake, the point was
assigned in the middle. The data should be displayed and analyzed at scales appropriate for 1:2,000,000-scale data.
No responsibility is assumed by the U.S. Geological Survey in the use of these data. Acknowledgment of the U.S. Geological Survey would be appreciated in products derived
from these data.
Northern snakeheads are represented with larger red markers. Click on a marker for more information. To REPORT an observation or collection of snakeheads, click here.
Suggested citation: Benson, A. J. 2009. Northern snakehead sightings distribution. Retrieved [add current date] from http://nas.er.usgs.gov/taxgroup/fish/northernsnakeheaddistribution.asp.
For more information, contact: Amy Benson, abenson@usgs.gov
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