


Why is a HiveSentry useful?
Most beekeepers cannot monitor their hives continuously. The apiary is too far away and the beekeeper has other work to do. Furthermore, frequent manual hive inspections are time consuming and disruptive to the bee colony. The HiveSentry allows monitoring the health of beehives unobtrusively over the internet.
What is the HiveSentry?
The HiveSentry is a continuous-wave radar that detects flying bees in front of the beehive. Its hardware is based on technology developed for automobile collision avoidance systems. Since the radar is capable of collecting a huge amount of data, a technique has been developed to reduce the data to a single number, which is the average power in the radar output frequency spectrum. We refer to it as the “bee activity index.” It is a measure of the number of bees flying out of and into the hive.
What does the HiveSentry look like?
Several versions of the HiveSentry have been developed. One version consists of a small waterproof box with a battery pack or solar pane. In a typical installation the HiveSentry is attached to the outside of a standard Langstroth bee hive as shown in the picture. Instrumented hives can be as much as 600 feet from the base station.

Typical HiveSentry Installation
How does the HiveSentry work?
The HiveSentry measures the activity index, hive vibrations and environmetal parameters such as solar radiation, temperature and humidity. The sensor transmits that information to a base station that collects messages for up to 10 sensors. The separation between the sensors and the base station can be much as 600 feet. The base station time stamps all messages and relays them to the internet via a WiFi connection.
How is the HiveSentry information to be used?

A comparison of activity levels with expected activity level, corrected for temperature and solar radiation has been found to be a powerful indicator abnormal hive behavior such as swarming and robbing.
Examples of Bee Radar Data
What is the development status of the HiveSentry?
The original concept of a Doppler based radar for monitoring honeybees was developed at the University of Maine in 2016. Twenty-four sensors were deployed in 2018 at several apiaries. Further refinements of the sensor were made in 2019. Eight units, as shown in the above picture have been deployed and have been operational since April 2020.
What is the long-term objective?
Our objective is to further validate the usefulness of the device, reduce the production cost, and transition the device into commercial production.