Pennsylvania Spatial Data Access

Abstract:

The concern caused by the explosive spread of the zebra mussel, (Dreissena
        polymorpha), within the United States resulted in passage of the
        Nonindigenous Aquatic Nuisance Prevention and Control Act of 1990 (P.L.
        101-646).  The impact of this biofouling pest on the economy and
        ecological processes in the U.S. and Canada has required prompt action on
        a large scale to prevent further infestations and minimize ecological
        degradation.  This map layer is a compilation of reports of confirmed
        zebra mussel sightings in the United States from 1988 to January 2008.
        It provides geographical and historical information to show distribution
        over time.  The reports came from a variety of Federal, State, and
        municipal agencies, public utilities, universities, engineering and
        private consultant firms.  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 export file.  This is a revised version of the
        June 2005 map layer.

Purpose:

The data are an essential part of the Department of the Interior's Nonindigenous Aquatic Species Program, <http://nas.er.usgs.gov/>. The data were compiled for use by resource managers to make them aware of zebra mussel occurrences so that they may help to control or prevent the spread of zebra mussels. These data are intended for geographic display and analysis at the national level, and for large regional areas. 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 or the National Atlas of the United States in the use of these data.

Supplemental_Information:

The original of this data set was published for and presented at the Third
        International Zebra Mussel Conference, held February 23-26, 1993 in
        Toronto, Ontario, Canada.  That data set was compiled by the Electric
        Power Research Institute of Palo Alto, CA, and published in June, 1993, as
        "A Geographic Information System (GIS) for Tracking Zebra Mussels
        (Dreissena polymorpha)in the United States".  The current data set builds
        on that original work.

Currentness_Reference:

ground condition

Use_Constraints:

None.  Acknowledgment of the National Atlas of the United States of America
      and (or) the U.S. Geological Survey would be appreciated in products derived
      from these data.

Address:

Florida Integrated Science Center, 7920 NW 71st Street

Attribute_Accuracy_Report:

All reports in the data base on zebra mussel locations were confirmed as being zebra mussels.

Attribute_Accuracy_Explanation:

A zebra mussel location was included in the data base if it was
          confirmed by a trained biologist or by someone who had received training
          to be able to identify zebra mussels.

Logical_Consistency_Report:

No tests for logical consistency have been performed on this map layer.

Completeness_Report:

This data base is by no means an all inclusive listing of zebra mussel
      locations.  But it is a fair and accurate representation of their
      distribution in North America.

Horizontal_Positional_Accuracy_Report:

Zebra mussel 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.  The locations were digitized as a
          single point in the reported water body at the place nearest to the
          town.  If no specific location was reported in a lake, the point was
          digitized in the middle.  These were all small lakes; the Great Lakes
          had specific locations associated with them.  Each zebra mussel sighting
          location was checked by manual comparison of the on-screen point with
          hard copy maps.

Process_Description:

After receiving a report of a confirmed zebra mussel sighting, the
          location was found on a paper map.  The scale of that map varied; we
          used the finest resolution available.  The point was then digitized on-
          screen using ArcInfo's arcedit feature, and was referenced to EPA
          Reach File Version 3.0 1:100,000-scale data (ArcInfo coverages in
          Albers Equal Area Projection).

Address:

Florida Integrated Science Center, 7920 NW 71st Street

Attribute_Definition:

Internal feature number.

Attribute_Definition_Source:

ESRI

Attribute_Definition:

Feature geometry.

Attribute_Definition_Source:

ESRI

Address:

Florida Integrated Science Center,7920 NW 71st Street

Distribution_Liability:

 Although these data have been processed successfully on a computer system at
      the U.S. Geological Survey, no warranty expressed or implied is made by the
      U.S. Geological Survey regarding the utility of the data on any other
      system, nor shall the act of distribution constitute any such warranty.  No
      responsibility is assumed by the U.S. Geological Survey or the National
      Atlas of the United States in the use of these data.  These data are not
      constituted legal documents and are not intended to be used as such.

Address:

115 Land and Water Building

Distribution_Liability:

The USER shall indemnify, save harmless, and, if requested, defend those parties involved with the development and distribution of this data, their officers, agents, and employees from and against any suits, claims, or actions for injury, death, or property damage arising out of the use of or any defect in the FILES or any accompanying documentation. Those parties involved with the development and distribution excluded any and all implied warranties, including warranties or merchantability and fitness for a particular purpose and makes no warranty or representation, either express or implied, with respect to the FILES or accompanying documentation, including its quality, performance, merchantability, or fitness for a particular purpose. The FILES and documentation are provided "as is" and the USER assumes the entire risk as to its quality and performance. Those parties involved with the development and distribution of this data will not be liable for any direct, indirect, special, incidental, or consequential damages arising out of the use or inability to use the FILES or any accompanying documentation.

Address:

Florida Integrated Science Center, 7920 NW 71st Street

Zebra Mussel Distribution in North America 2008