CoastWalking 2001 Update  Mapping Glacier Bay's Coast

by Lewis Sharman, Coastal Ecologist

2001 was the most productive year ever of the park's Coastal Resources Inventory and Mapping Program.  Last summer's Coast Walkers mapped 170 miles of the Bay's upper inlets, leaving only 35 miles of Glacier Bay proper remaining to be completed.

Field Work

The field inventory is performed by two-person teams walking the shore during low-tide "windows" and delineating polygons based on areas of similar surface beach substrate. Wet, rainy, rugged field conditions demand that data collection techniques be simple and reliable. Field crews map the coast by delineating segments as polygons on aerial photographs. Polygons are drawn directly onto 200% enlargement plastic photocopies of 1:24000 color infra-red photos. Additional field data is recorded onto plastic paper data sheets.

For each polygon, field data collected includes:

1.  Surface substrate characterization;

2.  A four-minute timed biological inventory of key intertidal flora and fauna;

3.  A transect from the water's edge to the woody vegetation to document vertical zonation patterns;

4.  A quick stream inventory designed to capture major stream characteristics;

5.  Three documenting photographs - one looking up from the water's edge toward the woody vegetation, and two taken looking left and right (down the beach) from mid-beach;

6.  Presence/absence of a variety of special-interest resource attributes such as archeological sites, offshore reefs, kelp beds, clam habitat, urchin recruitment areas, tide pools, and wildlife aggregation areas.

Global Positioning System (GPS) control points are collected in the field and used to georeference aerial photos.

Coast Walking Project

To date the project has mapped a total of 740 miles of the park's marine shoreline.  This project's end product displays data about beach surface substrate, slope, intertidal biota, vertical zonation, pinniped haulouts, seabird colonies, adjacent terrestrial vegetation, and a wealth of additional information in a coastal Geographic Information System (GIS) format.  The GIS is instantly available to resource managers and decision-makers on the park's computer network.  Users can literally "walk the beach" segment-by-segment on their computers, seeing high-resolution aerial photographs as well as detailed ground photos all along the way.  Images are directly linked to the tabular information, and all of it is connected to a master map of the park.  A user points-and-clicks to a section of beach on the map displayed on their computer monitor, and the GIS instantly takes her/him there and makes the connection to all associated data.  The system has been designed to be simple, fast, and dead-easy to use.  It quickly and easily provides a very large amount of important data for use in research, issues analysis, spill response, and development of long-term monitoring.  Indeed, the inventory data itself serves as a "baseline" to help define today's yet-healthy and relatively pristine coastal resource condition.  Currently, a major parallel program thrust is the development of a web-based version of the project so that the public will be able to access the information via the internet (hoped-for by the end of 2002).  For more information, visit http://www.nps.gov/glba/learn/preserve/projects/coastal, or contact Lewis Sharman, Coastal Ecologist.