Study: Wild turkeys not the vineyard pests some thought
By MARK HEDGES/The Daily Journal
Tuesday, February 04, 2003 -
A new study has revealed that wild turkeys eat less grapes than some vineyard owners suppose.
In fact, in a study conducted by the National Wild Turkey Federation and the California Department of Fish and Game in August 2002, wild turkeys eat less grapes than all the other critters caught raiding vineyards.
Because grape growers were seeking a culprit in damage to wine grape crops they were witnessing, they often became suspicious of wild turkeys, which are very fond of making patrols through vineyards in large groups, often trailing little rows of turkey chicks.
This prompted the turkey study.
Thirty nine cameras were placed at various places within six study sites in Napa, Sonoma and Mendocino counties, and photographs were taken of daytime and nighttime wildlife activity from Aug. 24, 2002 to September 25, 2002.
Some 431 animals were photographed in total, and 45 percent of those turned out to be wild turkeys doing their usual thing, twitching down the vinerows.
However, there was only a small percentage of wild turkeys that were actually eating any wine grapes.
Mostly, the turkeys were feeding on insects, which could be considered a pretty good thing for the grape vines, actually.
In contrast, 68 animals, or 16 percent, were deer. Of those, 21 percent were eating grapes.
Sixteen animals (4 percent) were foxes, and nearly 38 percent were eating grapes.
Surpassing these pigs, 70 percent of the ground squirrels (40 animals) and raccoons (37 animals) were chowing down on grapes that would have gone into fine wine.
Though more animals were seen during the day, more crop damage was occurring at night, and, in this, the turkeys stood especially vindicated. Wild turkeys are in the habit of flying to their roost trees before dark, where they usually stay for the night, so they're not even out when the worst grape pillaging is going down.
"Many times, when wild turkeys were seen moving through vineyards, they were actually feeding on many of the insects harmful to grape crops found on the ground below the vines and were not eating grapes at all," said Jim Stengle, NWTF regional biologist for California, after reviewing 1,588 photographs taken during the study. "The people that see flocks of wild turkeys walking through their grapes have assumed that they were responsible for all the grapes that were being eaten. Now, we can show that at these sites, it's mostly deer, raccoons and other wildlife that are eating the grapes at night. The study is a real eye-opener."
Other things the study pointed out:
Though fewer mammals were photographed, when they were on film they were usually helping themselves to grapes like little Bacchanalians.
Vineyard damage by wildlife was usually occurring only on the outside rows.
Vineyards reporting damage are typically new vineyards located next to excellent wildlife habitat.
Deer proof fences were 100 percent effective at preventing deer from entering the sites in the study. However, where there were holes in the fence, deer quickly discovered where they could enter the vineyard.
http://www.ukiahdailyjournal.com/Stories/0...57828%2C00.html
By MARK HEDGES/The Daily Journal
Tuesday, February 04, 2003 -
A new study has revealed that wild turkeys eat less grapes than some vineyard owners suppose.
In fact, in a study conducted by the National Wild Turkey Federation and the California Department of Fish and Game in August 2002, wild turkeys eat less grapes than all the other critters caught raiding vineyards.
Because grape growers were seeking a culprit in damage to wine grape crops they were witnessing, they often became suspicious of wild turkeys, which are very fond of making patrols through vineyards in large groups, often trailing little rows of turkey chicks.
This prompted the turkey study.
Thirty nine cameras were placed at various places within six study sites in Napa, Sonoma and Mendocino counties, and photographs were taken of daytime and nighttime wildlife activity from Aug. 24, 2002 to September 25, 2002.
Some 431 animals were photographed in total, and 45 percent of those turned out to be wild turkeys doing their usual thing, twitching down the vinerows.
However, there was only a small percentage of wild turkeys that were actually eating any wine grapes.
Mostly, the turkeys were feeding on insects, which could be considered a pretty good thing for the grape vines, actually.
In contrast, 68 animals, or 16 percent, were deer. Of those, 21 percent were eating grapes.
Sixteen animals (4 percent) were foxes, and nearly 38 percent were eating grapes.
Surpassing these pigs, 70 percent of the ground squirrels (40 animals) and raccoons (37 animals) were chowing down on grapes that would have gone into fine wine.
Though more animals were seen during the day, more crop damage was occurring at night, and, in this, the turkeys stood especially vindicated. Wild turkeys are in the habit of flying to their roost trees before dark, where they usually stay for the night, so they're not even out when the worst grape pillaging is going down.
"Many times, when wild turkeys were seen moving through vineyards, they were actually feeding on many of the insects harmful to grape crops found on the ground below the vines and were not eating grapes at all," said Jim Stengle, NWTF regional biologist for California, after reviewing 1,588 photographs taken during the study. "The people that see flocks of wild turkeys walking through their grapes have assumed that they were responsible for all the grapes that were being eaten. Now, we can show that at these sites, it's mostly deer, raccoons and other wildlife that are eating the grapes at night. The study is a real eye-opener."
Other things the study pointed out:
Though fewer mammals were photographed, when they were on film they were usually helping themselves to grapes like little Bacchanalians.
Vineyard damage by wildlife was usually occurring only on the outside rows.
Vineyards reporting damage are typically new vineyards located next to excellent wildlife habitat.
Deer proof fences were 100 percent effective at preventing deer from entering the sites in the study. However, where there were holes in the fence, deer quickly discovered where they could enter the vineyard.
http://www.ukiahdailyjournal.com/Stories/0...57828%2C00.html
