The well-known wildlife biologist who headed Minnesota's response to chronic wasting disease (CWD) and who paved the way for antler point restrictions for trophy-minded deer hunters in the Driftless Area has left his job at the Department of Natural Resources.

Citing personal reasons, Lou Cornicelli quietly departed the agency Aug. 3 after serving nine years as DNR's wildlife research program manager and another nine years as the agency's big game program consultant.

"Lou exemplified a scientist and public servant,'' said John Zanmiller, communications chief for Bluffland Whitetails Association in St Charles. "I'm hopeful the DNR will get someone of his caliber to replace him.''

Known best in recent years for leading an aggressive fight against the spread of CWD in Minnesota's white-tailed deer population, Cornicelli also brought expertise to the DNR on how to incorporate human dimension studies as part of wildlife management. He established a public deer population goal-setting process in the mid-2000s and implemented harvest strategies to meet those goals.

Cornicelli, 54, declined to comment. In November he lost his wife, Larissa Minicucci, to cancer. In Cornicelli's resignation letter to DNR Fish and Wildlife Chief Dave Olfelt, he wrote: "As many know, personal and professional life has taken a series of turns that I would wish on no other person. To that end, I believe it is time for a life change."

Olfelt said Cornicelli worked diligently for the DNR throughout his career. One project involved innovative work on lead fragmentation. Olfelt said Cornicelli fired various lead slugs and lead bullets into sheep carcasses and then x-rayed them to see where the fragments went. "That work convinced many to use non-toxic ammo,'' Olfelt said in an e-mail to the Star Tribune.

Zanmiller said Cornicelli sometimes came under personal attack for actions and decisions that didn't match the preferences of certain hunters, landowners and state-regulated deer farmers. The holder of a wildlife doctorate degree from the University of Minnesota, Cornicelli alienated deer farmers in the state with research that tied CWD outbreaks in wild deer to non-compliant deer farms. The attention resulted in a state audit that slammed the Minnesota Board of Animal Health for lax enforcement of regulations meant to keep captive deer and captive elk free of disease and away from wild deer.

"He was always open to questions from all different stakeholders and legislators,'' Zanmiller said. "He took a lot of heat but he maintained his professionalism.''

Zanmiller said antler point restrictions in southeastern Minnesota came about with Cornicelli's assistance after a contingent of deer hunters in the area pushed for a change in the hunting calendar. The group wanted to delay the firearms hunting season past the whitetail mating season, or rut, when bucks are most susceptible to hunters.

Zanmiller said Cornicelli convinced the group that changing the season wouldn't fly with legislators because of Minnesota's tradition. Instead, he championed a new regulation that prohibited hunters in the region from harvesting young, antlered bucks. The change allowed more bucks to grow into trophy-sized deer.

For this year's season, however, the antler point restrictions were removed as part of Cornicelli's system to thin deer herds where CWD has been detected. Cornicelli and many other wildlife biologists believe lower deer densities will help slow the spread of the disease. Under Cornicelli, the culling has included firepower from federal sharpshooters. The battle against CWD also has included wide-scale CWD testing of hunter-harvested deer and an ongoing study of deer movements in southeastern Minnesota.

Olfelt said Cornicelli was engaged in all aspects of Minnesota's response to CWD since the disease was first discovered in 2010 in a wild deer near a CWD-infected elk farm by Rochester.

"He represented Minnesota nationally on CWD issues, including the development of… best management practices in combating that disease,'' Olfelt said.

Cornicelli also was instrumental in the state's ongoing effort to figure out the decline of moose in the Arrowhead Region. Olfelt said Cornicelli helped get the funding and support to do adult and calf moose studies.

As the person who organized, implemented and provided overall scientific direction to all wildlife research, Cornicelli shaped the work of 35 staff members. But now, with most state agencies under a hiring freeze, Olfelt said he doesn't know when DNR will permanently fill the position.

For now, department insider Michelle Carstensen has been assigned to the acting role as wildlife research manager, Olfelt said. She worked closely with Cornicelli as supervisor of the wildlife health program. She works to protect moose, deer, waterfowl and other wildlife species from diseases that kill them.

Tony Kennedy • 612-673-4213