A long-range implantable heart rate transmitter for free-ranging animals

Area of Science:

• Wildlife biology
• Animal telemetry
• Physiological monitoring

Background:

• Understanding grizzly bear (Ursus arctos) physiology is crucial for conservation.
• Existing telemetry devices may not withstand harsh field conditions or long-term implantation.
• Accurate heart rate data is essential for assessing stress, activity, and metabolic states in wild populations.

Purpose of the Study:

• To describe the design and operational characteristics of a novel heart rate transmitter.
• To evaluate the suitability of this transmitter for long-term deployment in wild grizzly bears.
• To assess the transmitter's durability, range, and battery life under Alaskan field conditions.

Main Methods:

• Design and construction of a rigid, field-implantable heart rate transmitter capsule.
• Implantation procedures for wild grizzly bears in northern Alaska.
• Remote monitoring of transmitter function and signal range (4-5 km).
• Assessment of transmitter lifespan, considering seasonal variations like winter torpor.

Main Results:

• The transmitter capsule is durable and suitable for field implantation.
• Remote monitoring is effective up to 4-5 km.
• The transmitter exhibits a lifespan of approximately one year in Alaskan grizzly bears, accounting for a 7-month period of winter torpor and reduced heart rate.

Conclusions:

• The developed heart rate transmitter is a robust and effective tool for monitoring wild grizzly bear physiology.
• Its design facilitates field application and provides reliable data over extended periods.
• This technology can significantly advance research on grizzly bear behavior, health, and adaptation to environmental changes.