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Hi Sandylapper,in answer to your question from the previous post,here is an excerpt from an article on Eloise Anderson and Twist. If you want to read the entire article I have the link listed below. I think this article is from 1999. At the time of this article Twist, was being used as a area search dog,but since then he could have been cross trained as a cadaver dog,I just don't know. My gut feeling is he is not a cadaver do.Twist is mentioned by name in the 5th paragraph. What do you think?
link
http://www.cansel.ca/field/story1.asp

This is Eloise Anderson speaking:"In the type of searches that I perform with my dog there is a great probability that the person being searched for is alive," Anderson explained. "This is opposed to a search where the person being looked for is expected to be dead. In these latter cases, a cadaver dog is used. Cadaver dogs work closer to their handler in a more structured search pattern, which narrows the possibility that evidence will be disturbed. With an area search dog, the animal can be far out of the range of the handler. The dog will search through an area looking for a person. If the dog doesn't find anyone it will continue to search. If a person is found, the dog will pick up an orange rubber ring hanging from her neck called a 'bringsel', and return to the handler. This is her way of telling me, 'I've found someone. Follow me.' Since the dog can be a substantial distance from the handler when she makes the "find", it may take several reports and refinds before the handler actually reaches the lost person."

Accountability of the team's efforts is another major problem corrected with the use of GPS.

"Whenever a team returns from a search area the primary factor that a search coordinator must determine is how effective that dog and handler were in their search," said Anderson. "This is called probability of detection (POD). In other terms, what area was covered by the search team and, given the missing person was in that area, what is the percent probability that the search team would have found them? Also, dogs are a lot like people. They have good days and bad days. That's a problem that is effectively observed with the use of GPS".

On October 20, 1996, during a mock search exercise, Anderson and Sheehan strapped a small specially made backpack holding a GeoExplorer II to her four-legged coworker, Twist, and tested their ideas in a demonstration to other members of the Contra Costa County Sheriff's Search and Rescue Team. "This was an opportunity to test equipment and procedures in a non-life-threatening situation," Anderson said.

Four "lost" hikers were hidden in areas of the Mt. Diablo State Park in northern California as part of a mock search exercise. After Twist and Anderson competed each of their assignments, Sheehan downloaded the data obtained during the search using Trimble's Pathfinder Office software to post-process the data. "Not only did we track Twist's search path, but the GeoExplorer II told us that she was searching her assigned area effectively. GPS worked like a charm. The GeoExplorer gave us quality data and the Pathfinder Office software performed elegantly. It showed us where the dog had searched as well as areas where more searching may be needed. Further, we can process the search path data and analyze the terrain over which the dog has covered. The existence of accurate base data was key to our effort."

The effectiveness of a search dog's efforts is affected by many different factors, such as temperature, vegetation cover and wind conditions. All of these factors affect how far a scent can travel. A handler will develop a search strategy that will optimize the search coverage for the given search conditions. The stronger the wind and lighter the vegetation cover, the greater the distance the dog can pick up scent from the missing person. A GIS allows search coordinators to buffer the search path of the dog, providing an accurate measure of the area. A user will buffer the search path a lesser distance within heavier brush, which tends to hold a scent. "With the GPS loaded inside a backpack attached to the search dog we are able to not only collect points everywhere that the dog has been during her search, but we buffer the path to quantify areas the dog has covered with her nose as well," said Anderson. "When this data is restored into ArcView at the conclusion of the search exercise we are able to see with greater accuracy where that dog has been and what areas could be searched more thoroughly. The GeoExplorer takes much of the guesswork out of the estimation process and gives us a better estimate of POD. The POD is much less subjective thanks to the use of Trimble".