BroodMinder-TH Brood Sensor (Temperature and Humidity)

01 · 35 °C IS THE SIGNATURE OF BROOD

The solid indicator

A colony with brood holds the nest between 32 and 36 °C with a steadiness no other part of the hive has. That steadiness is the signature: while there is brood, the curve is almost flat.

When brood is missing — no queen, laying lost, or no nurse bees left — the temperature starts to follow the ambient and swing with day and night. And if it ends up matching the outside, the hive is inactive or dead.

02 · IT'S THE PATTERN, NOT THE NUMBER

How you actually read it

It is tempting to look for a table of values that diagnoses each thing, but a single reading says almost nothing: 34 °C can be a perfect colony or one in the middle of a change, depending on where it came from.

What informs you is the deviation: against the same hive over the preceding days, and against its neighbours in the same apiary under the same weather. That is why the device stores a history instead of giving one reading and stopping there.

03 · BLUETOOTH: TEN METRES

Before you picture yourself watching from home

The link is Bluetooth low energy with about 10 metres of range. Data is downloaded with your phone while you are at the apiary, using the BroodMinder Bees app, and goes up to the web from there.

This is not remote telemetry: the sensor on its own sends nothing to the internet. To see your hives without travelling you need to add a gateway to bridge it. If that is what you are after, tell us before you buy.

04 · HOW OFTEN YOU MUST DOWNLOAD

The memory arithmetic

Memory holds 7,000 records and the interval is configurable between one hour and fifteen minutes.

Doing the sum: at one reading an hour the memory lasts about ten months; at one every fifteen minutes, a little over two months. That is the real deadline for going to download before you lose the start of the series. The battery is a CR2032 and lasts close to a year.

05 · WHERE IT GOES

Sensor accuracy does not rescue a bad spot

It goes in the middle of the brood frames, right under the crown board. That is where the colony works its microclimate, and it is the only point whose reading means anything.

Put on an edge or on top of a honey super, the device will still measure to ±0.25 °C — but it will measure the edge. The accuracy figure belongs to the sensor; how representative the reading is comes from where you put it.

It also catches the event: faced with a sudden change, the sensor switches on its own to high-frequency sampling so it does not miss the detail of whatever is happening.

06 · BEFORE YOU BUY

This is the sensor: