Honey bee life spans are 50% shorter today than they were 50 years ago

Researchers also saw less honey being produced and greater colony losses among the honey bees, Mustafa Qadri writes

Honey bees are important pollinators for helping flowers, fruits and vegetables grow (Getty Images)

The lifespan for honey bees has decreased by 50 per cent compared to the 1970s, a study shows.

The average caged honey bee lives upto 17.7 days compared to 34.3 days in the 1970s, it found.

Researchers from Maryland University set out to find the lifespan by adding plain water to caged honey bees’ sugar water diet to better mimic their natural conditions.

They noticed that regardless of diet, the average lifespan of caged bees was half that of caged bees in similar experiments in the 1970s.

Additionally, they saw a reduction in honey production and a much bigger colony loss - when the majority of worker bees in a honey bee colony disappear.

A colony loss is normal for bees and an accepted factor in the beekeeping business, due to them naturally ageing and dying.

However, over the past decade, US beekeepers have reported higher loss rates and have had to replace the bee colonies to keep their business going.

Lead author of the study Anthony Nearman said: “We’re isolating bees from the colony life just before they emerge as adults, so whatever is reducing their lifespan is happening before that point.”

She added: “If this hypothesis is right, it also points to a possible solution. If we can isolate some genetic factors, then maybe we can breed for longer-lived honey bees.”

Caged honey bees used by Maryland University researchers (Anthony Nearman / UMD)

This is the first study to show an overall decline in a honey bee lifespan, potentially independent of environmental stressors, hinting that genetics may be influencing the broader trends seen in the beekeeping industry.

Although a laboratory environment is very different from a bees natural environment, records of lab-kept bees suggest a similar lifespan to colony bees.

Scientists generally assume that isolated factors that reduce the lifespan in one environment will also reduce it in another.

Other studies have also shown that shorter honey bee lifespans cause lower honey production. This is the first study to connect those factors to colony turnover rates.

The next steps for the researchers will be to compare trends in honey bee lifespans across the US and other countries.

The study was published on 14 November, 2022, in the journal Scientific Reports.