Accurate pacing, compasses, and night-sky navigation now share the outdoors with GPS systems and laser range finders. Field collection will never be the same.
GPS allows field researchers to pinpoint the location of observations (reportedly to within an inch or less with the most sophisticated systems). The US Department of Defense (DOD) manages a constellation of twenty-four satellites in high-altitude orbits, which continuously broadcast precise time and position data. By measuring the interval between transmission and reception of satellite signals, and triangulating data received from at least three satellites, a GPS receiver calculates a position fix, and displays it as longitude/latitude, map grid, or military grid coordinates. For species inventories, it makes for much more useful reporting than old systems that referenced names of towns, political boundaries, physical features, or other changeable markers.
In May, GPS became faster, more accurate, and less costly when President Clinton turned off the DOD's selective availability (SA) system. Using SA, the Defense Department had intentionally corrupted satellites' timing signals, in order to make readings less accurate to potential hostile users.
The basic item in a GPS "toolkit" is a GPS receiver. Most are manufactured by Garmin, Magellan, or Trimble (see their company-name.com Web sites or a mail-order catalog such as Ben Meadows Company, 800/241-2068, www.benmeadows.com). Prices depend on how much accuracy you need (accuracy is also affected by how many satellites can be "seen" from your location), and whether you want to connect your unit to a computer or use Geographic Information System (GIS) software. A "navigation-level" GPS receiver (e.g., a Magellan Pioneer) costs less than $100.
To save and transmit data electronically, add a computer, To receive and send data in the field, add a wireless modem. GIS software (see Whole Earth, Fall, 1998) lets you organize data, plot it on maps, or integrate it with a wealth of other information. It can customize data collection forms to simplify data gathering and standardize reports.
ESRI, the Environmental Systems Research Institute (www.esri.com) makes the most widely used GIS software, and offers many free downloads on their Web site. ESRI's Conservation Program (www.esri.com/conservation) offers assistance, including grants, to help nonprofits working in conservation, environment, and indigenous peoples acquire software and upgrade their GIS capabilities.
The biggest issue for groups putting together systems may be compatibility. Not all receivers, computers, and software work together. Charles Convis, ESRI Conservation Program director, rigged up one compatible palmtop field data collection system that gives two-meter accuracy, and GIS, for less than $500, using a Magellan 310 GPS, a Compaq Aero 2100 palmtop, and Arc/Pad GIS software.
COPYRIGHT 2000 Point Foundation
COPYRIGHT 2000 Gale Group
