#06–333 December 11, 2006
Wild turkey reproduction in state poor this summer
Based on a S.C. Department of Natural Resources survey, reproduction by
wild turkeys was poor for the second year in a row, according to a state
wildlife biologist.
Annually since the early 1980s, the S.C. Department of Natural Resources
(DNR) conducts a
Summer
Turkey Brood Survey to estimate reproduction and recruitment of turkeys
in South Carolina. The survey involves agency wildlife biologists,
technicians and conservation officers, as well as many volunteers from other
natural resource agencies and the general public.
As was the case last year, it appears that wild turkey reproduction was poor
to very poor in most regions and statewide, according to Charles Ruth, DNR
Deer and Turkey Project supervisor. Although wild turkeys nest primarily in
April and May in South Carolina, the survey does not take place until late
summer. Therefore, the survey statistics document poults (young turkeys)
that actually survived and entered the population going into the fall.
Although average brood size was good with hens averaging 3.4 poults, 50
percent of hens observed had no poults at all by late summer leading to a
total recruitment ratio of 1.7. Recruitment ratio is a measure of young
entering the population based on the number of hens in the population.
“In the Southeast,” Ruth said, “Mother Nature often plays a big role in
turkey populations with heavy rainfall and/or cool temperatures during the
spring nesting and brood rearing season leading to poor reproductive
success.” However, that does not appear to be the case in 2006. Comparing
climatic data from this year with historic data indicates that temperatures
were at or above normal and rainfall was below normal during the nesting and
brood rearing period. In other words, environmental conditions were such
that reproduction in turkeys should have been better.
“Perhaps we have reached a point in time where the relationship between the
turkey population and habitat is simply not as good as it was when turkeys
were expanding across the state,” said Ruth.
According to the survey, the Northern Coastal Plain experienced the best
reproduction in 2006, with counties including Berkeley, Clarendon, and
Williamsburg fairing better than most other parts of the state.
What does poor reproduction by turkeys for two consecutive years mean for
the spring turkey hunter? “With poor reproduction the last two years the
number of mature gobblers (2 years and older) available during the spring of
2007 will likely be low across most of the state,” Ruth said.
“Reproduction was good in 2004, but birds produced then have been subjected
to two hunting seasons in addition to other mortality factors. Not only is
the number of adult gobblers expected to be down in 2007, the survey results
indicate that the number of jakes (immature gobblers) will be low as well.
This is significant because jakes can make up 25 percent of the spring
harvest following years of good reproduction.”
The statewide turkey population is estimated at 90,000 birds, which is good,
but with two years of poor reproduction this figure is the lowest in recent
years.
“The bottom line,” Ruth said, “is that it will likely take a couple of years
of better reproduction to overcome poor reproduction the last two years.”
Hunters often wonder why DNR does not promote or schedule a fall turkey
season, and although there are a number of considerations, poor reproduction
like that experienced the past two springs is a very important factor.
“Bear in mind that hunting turkeys in the fall differs drastically from
spring gobbler hunting, which is familiar to most hunters,” Ruth said. “Not
only do hunting and calling techniques differ, fall seasons typically allow
hunters to take hens or gobblers. Although DNR monitors turkey reproduction
annually, the information is not available until about the same time a fall
turkey season would be underway, so it is too late to schedule a fall season
based on reproductive success or sound biology. DNR could simply schedule a
fall season without regard to reproductive data, but harvesting hens
following a summer with poor reproduction would further depress the number
of hens potentially leading to a rapid decline in turkeys.”
About 45,000 hunters participate in the spring turkey season,
contributing around $16 million to the state’s economy annually.