Hive Scales

A hive scale is a measuring device that weighs the whole beehive to show, without opening it, whether the colony is collecting nectar, how fast it is using its stores and whether sudden events such as swarming have occurred. Types range from mechanical platform scales to electronic models that send data remotely. Even a single, well-placed scale in an apiary makes decisions about feeding, adding supers and harvesting noticeably easier.

What is a hive scale used for?

A plant in flower is not necessarily yielding nectar. Drought, a cold night or wind shuts off secretion; the flowers are there but no honey comes into the hive. This difference is hard to spot by eye; if the weight is not rising, there is no forage. That is the most valuable thing a hive scale tells you.

A scale also answers these questions:

• Has the nectar flow started or ended? For adding supers or planning the harvest.
• Is the colony eating into its stores? For feeding and robbing precautions during a dearth between flows.
• Are the winter stores sufficient? To see the risk of starvation without opening the hive.
• Has something unexpected happened? Such as a swarm, robbing or the hive tipping over.

What types of hive scale are there?

How do you read a hive scale graph?

Hourly data from an electronic scale shows a clear daily cycle, even within a single day. Recognising this cycle prevents false alarms.

• Morning drop: When the foragers leave the hive the weight falls somewhat; this happens even when there is no forage.
• Rise from midday to evening: The weight climbs as nectar and pollen come in; foragers returning in the evening add to it.
• Slight drop at night: The hive loses water as the bees evaporate it from the nectar. This is a normal loss showing that the honey is ripening.
• Net daily change: The value that really matters for decisions is the difference from one midnight to the next.

Unusual signs

• Sudden, large drop around midday: A swarm may have left; a loss of one to several kilograms is typical. Check the same day.
• Rapid drop with no forage and fighting at the entrance: Suspected robbing. Reduce the entrance.
• Step-shaped rise or fall: Usually your own adding or removing of supers or feeding; if it is not recorded it will be misread.
• Marked acceleration of consumption in winter: Consumption rises when brood rearing starts in late winter; this is normal. But an acceleration in early winter suggests a disturbed or troubled colony.

Which decisions does a scale make easier?

1. Adding supers: If a net gain is seen several days in a row and the hive is nearly full, add a super.
2. Harvest time: When the gain stops, the flow is over; the ripened honey can be taken a few days later (check the moisture with a refractometer).
3. Feeding: If the weight keeps falling between flows, especially when there is plenty of brood, extra food is needed.
4. Winter stores: If you know the empty weight and the stocked weight of the hive in autumn, you can work out the remaining stores in winter without opening it.
5. Moving hives in migratory beekeeping: When the weight stops rising in one area, it is time to move to a new site.

How do you set up a hive scale?

1. Solid, level base: Use a concrete slab or compacted ground; soft soil sinks under the weight and spoils the readings.
2. The whole hive must be on the scale: The hive should not lean against a stand, a wall or a neighbouring hive.
3. Zero the scale (tare): Take a zero reading on the empty platform; if possible, check it with a known weight.
4. Protect it from rain and sun: Water damages electronics, and direct sun causes temperature drift.
5. Record every intervention: Adding or removing supers, feeding and frame swaps should be noted with the date and approximate weight.

How many hive scales do you need, and which colony should it go under?

In one apiary a single scale is often enough. Colonies in the same area work the same sources, and the scale becomes the apiary's "barometer". The colony on the scale should be of medium strength and typical: the strongest colony paints an optimistic picture, the weakest a pessimistic one.

Separate scales may be worth considering for apiaries at different altitudes or with different vegetation. If you are doing research or comparing bee races, you need at least one scale in each group.

What to look for when choosing a hive scale

• Capacity: A multi-storey hive full of supers can exceed 100 kg. The capacity should be comfortably above the heaviest case.
• Precision: A resolution of 50–100 grams is enough to see daily changes; what really matters is that it does not drift over the long term.
• Temperature stability: Cheap load cells can drift with the day–night temperature difference. Check whether the manufacturer provides temperature compensation.
• Durability: Water- and dust-resistant housing, stainless or galvanised frame.
• Power and data: Battery life, solar panel option, whether the data can be exported and whether there is signal at the apiary.
• Fit with your hive type: The platform must fully support the floor of the hive you use.

Weighing without a scale: the luggage-scale method

You can get a rough weight figure without buying a scale. A hand-held (luggage) scale is hooked under the back edge of the hive, the hive is lifted a few centimetres and the value is read; then the same is done at the front edge. The sum of the two values is close to the weight of the hive.

An even simpler method is to lift the hive slightly from the back and feel whether it is "light or heavy". It is not precise, but it works for checking for starvation in winter; if the same person does it the same way, comparisons are possible.

Common mistakes

• Putting the scale under the strongest colony and generalising the result to the whole apiary.
• Mistaking the morning and night drops of the daily cycle for a problem.
• Not recording supers, feeding and frame changes.
• Soft ground, a tilted set-up or the hive leaning on its stand.
• Thinking the scale can replace hive inspections: the queen, brood pattern and disease can only be judged by looking.