Key findings
- 1
Provided Japan's first evidence that sika deer stay through winter — overwinter — in forest above 1,600 m at Kamikochi.
- 2
Kernel density estimation (KDE) comparing summer (Aug 2025) and winter (Jan 2026) home ranges showed the winter core area was maintained in the high-elevation forest.
- 3
The tracked individual was a pregnant female, indicating possible breeding at high elevation.
Study overview
The survey continuously tracked, via Animal Portal, the locations of sika deer fitted with LoggLaw G2C at Kamikochi in the Northern Alps, revealing home ranges from August 2025 to January 2026.
It was conducted by Biologging Solutions in collaboration with the Natural Parks Foundation (Kamikochi branch; Sohei Katori) and Specially Appointed Professor Shigeyuki Izumiyama of Shinshu University.
The LoggLaw device and its role
LoggLaw G2C is a GPS collar for medium-to-large mammals combining high-precision GNSS positioning, real-time LTE-M transmission and a solar panel. It requires no local receiver and is built for long, stable operation in mountainous, cold environments.
Locations are visualized on a map in Animal Portal, with home-range display and multi-institution data sharing — which made it possible to capture a long, continuous phenomenon like overwintering.
Why it matters
Confirming sika deer overwintering above 1,600 m at Kamikochi is a first-of-its-kind finding in Japan and foundational data for conserving the Kamikochi ecosystem, including its alpine plant communities.
It demonstrates the effectiveness of science-based wildlife management built on GPS tracking and a cloud platform.
Source
PR TIMES（May 25, 2026）
https://prtimes.jp/main/html/rd/p/000000007.000114250.htmlRelated products & use cases
Sika deer use case (LoggLaw G)
A use-case guide to deploying GPS collars for sika deer behavior surveys and management.
LoggLaw G2C — collar-type GPS
Used in this study. A collar GPS for medium-to-large mammals with GNSS, LTE-M and solar charging.
Animal Portal — wildlife data cloud
Visualizes and shares GPS data on a map, with home-range display and proximity alerts.
Digest by
A graduate of Kyoto University's Graduate School of Informatics and UC Santa Cruz's School of Environmental Studies. As co-founder of Biologging Solutions Inc., a Japan-based biologging equipment manufacturer, he oversees deployments of the company's products with municipalities, universities, and international consortia.
A biologging researcher with field experience including video-logger studies of penguin behavior in Antarctica. As co-founder of Biologging Solutions Inc., he leads the development of compact data loggers, GPS collars, and video loggers built directly around real-world research needs.