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Hobbs State Park's Wild
Turkeys
Wild turkeys are unique natives of our forest community. Members of the pheasant family, some wild turkeys reach a weight of twenty-five pounds, making them North America’s largest game bird. Domestic turkeys are descendants of the wild turkeys though they differ significantly. While wild turkeys prefer to run, they are able to fly and usually rest in trees. Females are called hens and their young, hatched in the spring, are called poults. By fall, the poults have matured; these young males are called jakes. The adult males are called toms or gobblers. Both sexes produce a wide array of vocal sounds. The gobblers tend to be the most vocal of them all. Adult wild turkeys feed on numerous plants’ produce called mast foods. While many plants’ buds, leaves, seeds and fruits are seasonal, oak acorns are a year-round staple. Insects are a major food source for young poults; adults occasionally eat insects as well. Wild turkeys compete with other creatures such as deer for food, so mast production is very important for sustaining a resident population. Turkeys and their young are subject to predation from wild and domesticated animals however; turkey’s greatest threat is habitat destruction along with over hunting. Even though the population today seems stable, people must monitor the situation in order to determine what actions to take and what regulation to enact. Annual surveys are conducted at Hobbs State Park to estimate population. The Spring Gobble Survey is designed to determine the location and numbers of gobblers on the park. Four survey routs are run simultaneously by motor vehicle, each including eleven listening positions marked on the route. Forty minutes before sunrise, the observer starts the survey by standing 30-60 feet away from his/her vehicle and listens at the first position. The observer listens for 5-7 min. after which records the number of gobblers heard, how many times each bird gobbled, the general location of the gobblers, habitat type, and any interference that could reduce hearing (airplanes, songbirds, traffic etc.) Each time a route is run, it begins from the end of the previous run. It is important to note that the observer does not use any calls or devices to stimulate or gobbling response. This survey has been conducted since 1989 but certain years the survey was not completed due to rain, winds, lack of participants and other special circumstances. The years that data was collected from the four routes, differences occur in the number of times each route was run. Compensation for these differences was made by averaging the number of gobblers heard by route, then adding each route together to get a total average number of gobblers heard. (Graph 1)
Another important method of data collecting is the spring harvest. Turkey hunting is open to the public each spring at Hobbs. Male turkeys only may be taken. Hunters are required by law to check their bird at a state authorized wildlife check station. Data is retrieved from the two stations adjacent to the park and listing the turkey as either a jake (young male) or a gobbler (adult male). (Graph 2)
Rainfall is extremely important to the whole park ecosystem. Sufficient rainfall is needed for plants to produce edible materials for all wildlife in the forest. When rainfall is low, all animals struggle and compete for the limited food (mast crops) available. Rainfall is measured and recorded daily, then compiled annually by Hobbs Sate Park Employees. (Graph 3)
Although wild turkeys are omnivores, white oak acorns are thought to compose most of the adults’ diet. The amount of acorns produced each year is estimated by conducting the mast production survey in the fall. A Hobbs employee and a student examine select trees. Each tree’s productivity is estimated as a percent (0%= no acorns, 100%=maximum production). The results are then used to determine the productivity range of that particular tree and place it in one of four % range groups: 0%-5%, 6%-33%, 34%-66%, and 67%-100%. Then all trees are totaled and a percent of how many trees per group are given. This is done on the hilltops (ridges) and the valleys (bottoms). (Graphs 4 and 5)
After examining the data one may conclude that the wild turkey population is relatively stable except for the record low number of gobblers heard during the 2003 gobble survey. This may be reflective of the fact that the record high number of turkeys harvested (22 gobblers, 9 jakes) was set the previous year of 2002. Another possible contributor to the recent decline in population relates to the annual rainfall. When rainfall exceeds twenty inches for the year, the poorest production range of white oak acorns significantly declines on the ridges thus, more production occurs in the three higher producing groups. The bottoms seem to be consistently poor producers. The last three years have seen rainfall below twenty inches; the mast production is reflective of this. This may indicate the turkeys are relying more on other plant species for food. Competition from other animals in these dry years may also be a contributor. No data is available for the population of predators at the park, another major factor. Hobbs wild turkeys may benefit from eliminating turkey hunting or a permit controlled system, thereby limiting the turkeys harvested. This action might only be necessary for a few years until the population rebounds. The poults might benefit from further clearing (controlled burns) of forest undergrowth, providing them with a larger area to forage for their primary food, insects. Wildlife and habitat management is essential for wild turkeys during this time of ecologically overwhelming urban sprawl. Many years of data from the surveys presently conducted and surveys investigating other factors not yet considered, will give one a better picture of what is occurring in the wild turkey population of Hobbs State Park.
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