The LOCNEST System

The tag

Light enough to be carried, with enough range to be tracked!

Weight: 0.13 grams

The first requirement is that the hornet accepts the beacon—that is, it returns to normal behavior as quickly as possible after being equipped. The lighter the beacon, the easier it is to tag smaller hornets, allowing us to start tracking earlier in the season without needing to selectively choose larger individuals. Note: 0.13 g is barely heavier than a honeybee.

Range: 3 km

This is the measured range in open space using the recommended receiver. Note: Humidity affects signal range. The actual range is a combination of transmitter power, environmental attenuation, and the sensitivity (and gain) of the receiver. This figure is a minimum expected range—many beacons achieve more, sometimes significantly more.

Transmission Duration: 3 hours

This duration is a compromise between transmission power, weight, and beacon frequency. The goal is to locate the nest quickly and efficiently! The duration could be increased, but at the cost of added weight.

One beep every 2 seconds

More frequent beeps drain the battery quickly; less frequent ones slow down the search.

The Receiver

A good receiver is: lightweight, sensitive, and directional!

7-element YAGI antenna

The antenna needs to be directional to precisely identify the signal source. Directionality also comes with beneficial gain, which improves receiver sensitivity and overall tracking range. The recommended antenna is 70 cm long and weighs under 1 kg—ideal for tracking.

SDR dongle

This is a USB stick that plugs into a phone. It converts the analog signal received by the antenna into a digital signal that can be interpreted by software. The recommended SDR key is a technological marvel: for its price, it offers exceptional quality—sensitivity, stability, and durability.

SDR Software

Software is required to interpret the received signal on a phone or PC. It provides both visual and audio representations of the signal at the target frequencies. Intuite has developed dedicated tracking software: SDR Pro Track.

Android Phone

Currently, only phones (and tablets or PCs) support the SDR key, which delivers the best results. The phone is naturally the most portable solution.

The Tracking Process

capture

The first step is to capture at least one hornet—using a trap or a fine-mesh net.

Capturing the hornet is the first step in a protocol where each phase must be carried out with care. For many, this involves catching one with a quick sweep of a net near a hive. Choose the largest specimen possible. Some prefer using bait, which has the added benefit of feeding the hornet. At this time, there’s no strong preference between trapping or netting—we haven't done a full comparison yet. After capture, place the Asian hornet in a test tube. Have all necessary tools ready for this step.

Equipping the tag

Next, the tracker equips the hornet with the transmitter, then releases it.

La This step is critical. Hundreds of trials have led to a protocol that ensures the hornet resumes flight quickly without being overly burdened. phase d'équipement de la balise est cruciale. Plusieurs centaines d'essais ont été réalisés afin de proposer un protocole qui permet au frelon de repartir rapidement sans être "trop" gêné par la balise.

Anesthetize the hornet using cold. Place the test tube in an ice tray for a certain period. Duration depends on the tube’s material, size, thickness, the temperature of the ice tray, and the ambient temperature. A good starting point is 11 minutes. Alternative methods like CO₂ exist, but Intuite hasn’t had success with them.
Attach the beacon before it wakes up, without harming it. Intuite has developed a special tool (the LOCNEST hornet holder) to position the hornet, apply glue, and hold the beacon in place during drying. The hornet wakes up after 1–2 minutes.
Feed the hornet before release. For now, this is done with a honey drop via pipette. Many other feeding methods are being explored.

Ground Tracking

Use one or more high-gain directional antennas to triangulate the signal.

Currently, tracking is a “hot or cold” game: pointing the receiver in the right direction gives a strong signal—both visually and audibly. You follow the hornet this way. However, a few things must be kept in mind:

While the range is around 1 km, that’s in open space. Obstacles like vegetation can reduce it.
Losing the signal can make it very difficult—or impossible—to relocate the hornet before it reaches its nest. So it’s essential to be organized: observe flight directions ahead of time, identify possible paths, and prepare for pursuit by mapping out roads, topography, and obstacles.
Hunting in teams will likely be crucial, especially early on.
The hornet handles the beacon very well and does not stay long at the nest (except at night).
Intuite is working on advanced triangulation solutions and using drones to assist in pursuit—but that’s still in development!