Three California Department of Fish and Game biologists and a pilot were killed Tuesday afternoon when their helicopter crashed in a craggy stretch of the Sierra National Forest where they were surveying wildlife.
The crash happened in a narrow canyon near Redinger Lake after the Bell 206 helicopter struck a power line and sparked a blaze that scattered debris throughout a quarter-mile of brush, Madera County officials said.
Killed in the accident were two longtime state scientists, 48-year-old Clu Cotter and 40-year-old Kevin O'Connor, as well as a scientists' aide, 31-year-old Tom Stolberg, all of Fresno. Pilot Dennis Donovan also died, but his hometown and age were not released.
The men were conducting a routine aerial mission to study deer herds feeding in the steep, wooded region near the border of Fresno and Madera counties.
"This is just such a tragedy," said John Baker, the agency's Central District assistant chief. "Clu and Kevin were both wonderful family men and great friends, and Tom was just a quirky, neat guy with real varied interests. Finer people you could never meet."
The fire made the site inaccessible for several hours, but crews put out the blaze and had located the four men's bodies by late afternoon, sheriff's spokeswoman Erica Stuart said.
Harry Morse, a Fish and Game spokesman, said the agency contracted the helicopter from Landells Aviation of Desert Hot Springs.
A woman who answered the phone at Landells confirmed one of its helicopters was involved in the crash but could not provide other details and would not give her name.
Another Landells helicopter crashed in January 2007 during a deer-monitoring trip in the nearby Tulare County foothills, but the three men aboard experienced only minor injuries.
Gov. Arnold Schwarzenegger and members of the California Association of Professional Scientists offered their condolences and hailed the scientists' service.
Cotter's Facebook page describes him as a wildlife biologist who specialized in mesocarnivores and an avid bike rider who graduated from Cal Poly.
O'Connor, an environmental scientist, wrote about the diverse plant and animal species found in the state's ecological reserves in the southern Sierra Nevada range.
Several people familiar with their missions called the surveys risky work that often involved flying close to the ground in rugged terrain to study deer population and migration patterns.
"We knew them, and it hits home," said association Staff Director Christopher Voight.
The department temporarily grounded all helicopter surveys and captures Tuesday afternoon, and the National Transportation Safety Board was expected to take over the investigation of the crash.
Associated Press Writer Terence Chea in San Francisco contributed to this report.