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Declining reptilian populations have been a growing concern over the last
couple of decades. One such declining species of concern, the Blanding’s
turtle (Emydoidea blandingii), occurs as isolated populations in North
American prairie-wetlands and is at risk of extirpation due to habitat
loss and fragmentation, and increased predator (e.g. racoons, coyotes)
populations due to supplemented resources in urban environments. To help
mitigate declining populations, wildlife managers have invested in the
conservation of this species through head-starting (i.e. reared in
ex-situ) and juvenile release programs to augment wild Blanding’s turtle
populations. However, much of their spatial and winter/thermal ecology is
understudied, and data for juveniles, and juveniles reared in ex-situ is
especially scarce, yet this information is imperative to understanding
shortfalls and improving head-starting efforts in the future. In spring
2016 (RR2016) and 2017 (RR2017) we released a cohort (n=12 each year) of
head-started juvenile Blanding’s turtles equipped with radio transmitters
and temperature dataloggers into a prairie-wetland in the greater Chicago
region, North America. Using ground-based radio telemetry, we determined
seasonal movement areas (SMAs; spring, summer, and fall) and annual home
ranges (AHRs) for both RR2016 and RR2017 cohorts via Kernel Density (KD)
estimates. We also investigated the thermal characteristics of
overwintering for both juvenile cohorts. We found that SMAs for the RR2016
cohort, but not for the RR2017 cohort, significantly differed across
seasons for most SMA estimators. We also found that juveniles in both
cohorts not only survived overwintering but also displayed similar
overwintering phenology (i.e. initiation: October-November; termination:
April) and temperature variation as Blanding’s turtles adults in other
studies. Overall, our results indicate that head-started juvenile
Blanding’s turtles may be able to acclimatize quickly to their natural
environment post-release. Our study provides evidence of the efficacy of
well-developed head-starting programs that aim to augment and preserve
imperiled turtle populations.
118 views reported since publication in 2022.