*An earlier version of this story misstated the impact of acorn production for deer.
COLUMBIA — The effects of the ongoing drought will be noticed by deer hunters this fall — and for years to come.
An outbreak of hemorrhagic disease that has put a dent in the statewide deer population, along with the smallest Missouri acorn crop on record — both related to the ongoing drought — are expected to have a bearing on the firearms hunting season that opens Saturday.
State deer biologists expect hunters to see fewer deer during the firearms season that runs through Nov. 20 and forecast a total deer kill of about 274,000 — close to the 274,794 deer killed last year by both firearms and archery hunters.
The biggest influence on Missouri's white-tailed deer population is the number of acorns, a mainstay of their diet, and the drought contributed to the smallest Missouri acorn crop in the history of the 52-year-old oak mast survey.
Hunters would be wise to find red oaks, often found on north-facing slopes. Red oaks have pointed leaves; white oaks have rounded leaves.
Red oaks produce acorns on a two-year cycle, meaning they were not as affected by the drought as white oak trees. White oaks produce acorns on a one-year cycle and do not handle droughts as well as red oaks.
In Boone County, acorn production for white oaks was down 78 percent, and acorn production for red oaks went down 29 percent from 2011.
With fewer acorns, more deer will be concentrated at oaks that produced nuts, potentially exacerbating an outbreak of deadly hemorrhagic disease that has been attributed to more deer gathering at fewer water sources.
Jason Sumners, a deer biologist with the Missouri Department of Conservation, estimated the deer at 1.4 million. Hunters can expect to see fewer deer this fall, but he expects hunters to kill about the same number as last year.
"In a year without a drought, a hunter might see 10 deer and harvest one," Sumners said. "In the next two, three years, a hunter might see five deer and harvest one."
Boone County was the fourth hardest hit county in the state by the disease outbreak that Sumners estimates has caused a 15 to 20 percent population decline in counties hardest hit. In localized areas, he said, the disease could take out up to half of all deer.
Flies that spread the hemorrhagic disease were expected to have been killed by cold weather by now, but the Department of Conservation continues to field scattered reports of the disease in northern Missouri.
Blue tongue and epizootic hemorrhagic diseases are spread by biting flies, sometimes called midges. They are both caused by a similar virus. Deer with the disease die within eight to 36 hours. The disease can be spread to cattle but not to humans.
"The nature of hemorrhagic diseases is it tends to be (concentrated) in little hotspots," Department of Conservation spokesman Jim Low said. "Part of a county's population is down. Twenty miles away, you'd never know it."
In the southern Missouri Ozarks, hunters are expected to take home more deer than last year. A strong acorn crop last year allowed deer to spread out in the forest, making it difficult on hunters. Fewer deer were killed, and the population increased.
This year the acorn production in the Ozarks was smaller, thus there will be more deer feeding at fewer oak trees.*
Hunting has been seen as the main tool in keeping the deer population across Missouri in check, Sumners said, but there won't be the same need in the next two to three years.
Supervising editor is John Schneller.