Preliminary Results of Upland Game Bird Brood Production in Wisconsin Present Mixed Picture
MADISON — Variable spring weather and habitat conditions in Wisconsin in 2008 created conditions for upland game bird brood rearing that were slightly cooler and much wetter than in 2007, according to analysis of annual game brood surveys conducted by state wildlife biologists around the state.
Cool and very wet conditions occurred for some of the critical early brood rearing season, while most of the later brood rearing period had average temperatures and rainfall during the summer of 2008.
“Much of the southern third of the state experienced large and frequent rain events early in the brood rearing season, when chicks are just hatching and have a hard time regulating their body temperature,” says Sharon Fandel, assistant upland wildlife ecologist with the Wisconsin Department of Natural Resources. “These events did not occur statewide, but probably did have an impact on local brood survival.”
Each year, DNR field staff report the number and size of game bird broods they observe in the field from June 15 through August 23. At the end of the survey period, these reports, known as the 10-Week Brood Survey are complied and summarized by the wildlife research program.
Statewide, Fandel says, the 2008 brood rearing season was somewhat worse than 2007, which was an average to above average brood rearing season. The following are survey results for the turkey, ruffed grouse and pheasant surveys.
Turkeys showed a 12 percent decrease in the number of broods seen per observer and an 8 percent decrease in the size of the broods seen. In 2008, DNR field personnel averaged 3.5 turkey broods seen during the survey period, down from the 4.0 broods per observer in 2007.
“But this was still well above the long-term mean of 1.6 broods seen,” Fandel notes.
The average size of a brood seen in 2008 was 4.5 young per brood, while in 2007 the average brood size was 4.9 young per brood.
“While statewide averages show only a slight decline in turkey brood production, heavy sustained rains early in the brood season in the southwestern parts of the state likely had an impact on local production,” she says.
Fandel says pheasants did not fair as well as turkeys from the early June rains and most of Wisconsin’s primarily pheasant range was affected by these weather events.
“Pheasant numbers will be down this fall compared to last fall’s hunting season. The number of pheasant broods seen per observer was down 42 percent from last year, and 52 percent below the long-term average,” she says.
Average size of the brood was down as well with 4.5 young per brood in 2008 compared to 5.1 in 2007. The Rural Mail Carrier and the Spring Breeding Pheasant surveys both also showed a decrease in the number of breeding pheasants in the spring of 2008. Production is additionally likely impacted by declining grassland habitat throughout the pheasant range.
The primary range for ruffed grouse, the Central and Northern forest portions of the state, were mostly spared from the heavy rain events of June. The average number of broods seen and the average size of the brood both increased 12 percent from 2007 levels.
DNR field personnel averaged 1.03 broods seen during the 2008 survey period, compared to 0.92 in 2007. Brood size was up as well with broods averaging 4.7 young per brood, 4.2 in 2007.
“There was also had an increase in the number of breeding ruffed grouse shown in the spring drumming counts,” Fandel says. “While some areas of the state surely saw losses from spring rains, it appears that ruffed grouse numbers this fall will be better than in the previous three to four years and are well on their way to their cyclic high.”
FOR MORE INFORMATION CONTACT: Sharon Fandel – (608) 261-8458