COLUMBIA -- Annually since the early 1980s, the S.C. Department of Natural Resources has conducted a Summer Turkey Survey to estimate reproduction and recruitment of wild 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. This year more than 300 observers recorded 1,866 unique observations, seeing more than 10,000 turkeys across the state in July and August.
This was the best participation in the survey in 10 years. More observations lead to higher quality data and better confidence in the information collected.
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 fall population.
Reproduction in turkeys has generally been low for the last 12 years. This year, average brood size of 3.4 poults remained good, but the Total Recruitment Ratio was 1.5, a less-than-desirable figure. This low number was driven by a high percentage of hens (55 percent) that had no poults at all by late summer.
TRR has averaged 1.5 over the last five years -- with 2.0 being somewhat of a break-even mark. When turkey populations were expanding during the 1980s, recruitment ratio averaged 3.5. Total Recruitment Ratio is a measure of young entering the population based on the number of hens in the population.
Although this observed measure of reproduction was poor in most of the state and definitely lower than desired, the good news is the recruitment index has been stable over the past five years and the downward trajectory of the population has stalled the last several years.
Unlike deer, wild turkeys are much more susceptible to significant fluctuations in reproduction and recruitment. Lack of reproductive success is often associated with bad weather (cold and wet) during nesting and brood rearing season.
However, there are a host of predators that take advantage of turkey nests and broods: raccoons, opossums, skunks, armadillos, snakes, foxes, bobcats, and numerous avian predators.
Coyotes, which are not native but are now well established in the state, can be added to the list of turkey predators. Additionally, feral hogs are expanding on the landscape and can be a significant nest predator.
Turkeys naturally have high reproductive potential and are therefore able to maintain populations in spite of predation and other mortality factors.
What does reproduction last summer mean for the spring turkey hunter?
Spring harvest trends have followed trends in reproduction for many years. For example, the harvest in 2015 was down significantly, which was not a surprise because reproduction in 2013 was the lowest on record.
The 2016 spring harvest showed a 10 percent increase over 2015. Just as the reduced harvest in 2015 was explained by the all-time low reproduction in 2013, the increase in harvest seen in 2016 was likely a result of slightly better reproduction in both 2014 and 2015, which led to an increase in turkey numbers in many parts of the state.
The 2017 spring harvest (19,171) was up 14 percent over 2016. The association between changes in reproduction and its effects on harvest are rather remarkable in South Carolina's turkey harvest and reproductive data sets.
Based on this information and the 2016 summer recruitment numbers (TRR=1.8) being the highest since 2012, another increase in the harvest can be expected in spring 2018.
Finally, the gobbler-to-hen ratio during last summer's survey was 0.58, which is average for the past five years. Low gobbler-to-hen ratios can affect the quality of hunting because hens are extremely available, which affects gobbling and responsiveness to calling by hunters.
The bottom line is the 2017 turkey harvest was 25 percent below the record level of 15 years ago. However, that 2002 record was a one-time peak and the 2017 harvest estimate is dead on with the average gobbler harvest over the last 22 years.
That fact, combined with five years of stability in the summer survey data, offers encouragement that the long-term population trend is leveling off and moving toward static.
Anyone interested in participating in the annual Summer Turkey Survey is encouraged to sign up. The survey period is July 1-Aug. 29 annually and those who participate typically spend a reasonable amount of time outdoors during that time period. If you would like to participate, contact Jay Cantrell at firstname.lastname@example.org.