Introduction of the Wild Turkey North of its Original Range into Northern Wisconsin
File(s)
Date
1981-12Author
Acker, J. Randolph
Publisher
University of Wisconsin-Stevens Point, College of Natural Resources
Metadata
Show full item recordAbstract
This study was undertaken to describe home range,
habitat use, mortality factors, and reproductve success of
eastern wild turkeys (Meleagris gallopavo silvestris)
introduced north of their original range into northern
Wisconsin. During winter 1977 and winter 1978, 81 wild
turkeys were trapped in Roscommon County, Michigan and
released in the southern end of the Nicolet National Forest.
Twenty hens ( 5 in 1977 and 15 in 1978) were radio-tagged;
1488 radio locations were recorded. Home ranges were
determined for monthly and seasonal periods using Minimum
Area and Modified Minimum Area Methods. Habitat use was
determined by plotting locations on timber-type maps and
calculating importance value ranks for each habitat type.
Data were analyzed for monthly periods; separate analyses
were conducted for each release site and age class.
Home range size and habitat use showed monthly and
seasonal changes that were affected primarily by weather,
reproductive behavior, and distribution of food resources.
When snow depth was greatest, during February, home ranges
averaged 6.3 ha for adults and 8.3 ha for juveniles and were
the smallest observed during the study. Oak (Quercus spp.),
aspen (Populus spp.) and conifer stands were used
extensively, but only conifers were characteristic of all
wintering areas. Settled snow in conifer stands allowed
turkeys to move on the ground, and was the major factor
affecting habitat selection.
March and April home ranges increased substantially
as a result of moderating winter conditions and spring
dispersal. Average April home ranges of adults were 20 times
larger than during February, and those of juveniles were over
40 times larger. Adult hens at 1 release area showed
increasing use of oak and open habitat, whereas a single
surviving adult at a second release area used aspen and
northern hardwood habitats. Juveniles continued to use oak,
aspen, and conifer habitats.
All radio-tagged hens nested during May and showed great
variation in selection of nesting habitat.
During June and July, adult hens with broods increased
their home ranges (June 61.5 ha, July 144.7 ha) probably
reflecting growth and increased mobility of young. Aspen was
most commonly used in June. Two adults with broods shifted
to almost exclusive use of open habitat during July while a
third adult with a brood continued to use aspen. Juvenile
hens, none of which nested successfully, had an average home
range size of 134.5 ha during June. Their home range
decreased in July to 104.4 ha. During these months juveniles
used aspen, northern hardwood, lowland hardwood, and oak.
Home range size decreased sharply during August with
adults covering an average of 20.1 ha and juveniles using
72.0 ha. Habitat use was similar to that of July for both
age classes.
Starvation was the most important mortality factor.
During 1978 (an average winter) it accounted for a minimum
mortality of 57% for radio-tagged adult hens and 50% for
radio-tagged juvenile hens.
All radio-tagged hens which survived the winter nested.
Adult hatching success ranged from 66 to 100% while that of
juveniles was 0%. Poult survival at age 6 weeks or older
ranged from 50 to 75%·
Extrapolation of 1978 telemetry data to the entire
introduced female population indicates that there were 35
females in the study area as of August 1978, 4 less than were
introduced during winter of the same year.