Long-term study confirms pollen-replacing feed strengthens honey bee colonies

A man-made food source provided honey bees a nutritious diet at a commercial scale over the course of two winter seasons, according to a new study led by Washington State University researchers.

The study, published in the journal Insects, looked at the new feed as used by five commercial beekeepers in California and Idaho from fall 2022 to spring 2024. This study is a follow-upto an initial paper describing the bee feed.

The nutritionally complete feed, which resembles an oversized, very thin granola bar, was developed by APIX Biosciences, a biotech company based in Belgium with a U.S. subsidiary. The company worked with WSU's Honey Bee Program to test the nutritional supplement.

"The first paper was a trial during the spring and summer pollination season to make sure the feed worked in real-world field conditions," said Brandon Hopkins, WSU's P.F. Thurber Endowed Distinguished Professor of Pollinator Ecology and a corresponding author on the paper. "This study happened during the other half of the year when beekeepers tend to see the biggest losses and depend the most on supplemental feeding. It was also done on a significantly larger scale than our previous study."

The participating beekeeping operations each manage more than 2,000 colonies. For the study, a selection of each of their colonies received the new feed and another equally sized group of colonies received the normal fall/winter feeding preference of each beekeeper.

Every participant continued the feeding cycle from the end of pollination season, when supplemental feedings normally start, through the end of the vital California almond pollinating season.

In a hypothetical 100-colonyoperation, the man-made food source would generate over $12,000 in additional gross revenue in the first year.

Colonies fed the pollen-replacing feed stayed healthier and performed better through winter and the almond pollination season. By January, during almond pollination, those colonies had more adult bees, and more of the colonies met the requirements for premium pollination contracts. After almond pollination, those colonies also survived winter at higher rates. Winter mortality dropped from 28.8% with a commercial standard diet to 15% with the new feed, a nearly 50% mortality reduction.

In January, "treated" colonies had larger adult populations and more offspring than colonies fed conventional commercial diets. After almond pollination in March, the treated colonies came out of almonds with 36% more adult bees and 40% more brood, giving beekeepers significantly more bees heading into the rest of the season.

This stronger performance translated into real economic value. In a hypothetical 100-colonyoperation, the new feed would generate over $12,000 in additional gross revenue in the first year.

"Healthy nutrition helps colonies thrive," Hopkins said. "Malnutrition leads to greater pest and disease susceptibility, one of the biggest contributors to colony loss. In addition, good forage areas with a variety of pollen availability are becoming more rare and more crowded with bees. This feed helps alleviate those pressures."

Hopkins and his team worked closely with Thierry Bogaert, chairman at APIX Biosciences, and his colleagues.

"The current mortality rate for honey bees is not sustainable," said Bogaert, a corresponding author on the paper. "While these findings demonstrate a clear survival benefit, our feed is not a silver bullet that can resolve every challenge bees face, such as varroa mites and pesticides."

Using the product when colonies require supplemental feeding represents an effective strategy to support colony strength and long-term resilience, Bogaert said.

Hopkins said he's unaware of any other published feeding study conducted on a scale of this magnitude.

"Beekeepers experience such high environmental variation, so the only way to show the impact is with huge sample sizes," Hopkins said. "It's very difficult, which is why it's never been done before. But this makes the study commercially relevant to both APIX, as the feed producers, as well as beekeepers, who now know this can help their colonies."

The agricultural and other benefits the large-scale study found could be noticeable soon. The company already is taking pre-orders, with the first commercial shipments of the feed expected to be ready for U.S. beekeepers by mid-June, Bogaert said.

Meanwhile, WSU's role in proving the efficacy of the man-made bee food was praised by administrators.

"Pollinators in general, and honey bees in particular, play a vital role in our food systems," said Raj Khosla, the Cashup Davis Family Endowed Dean of WSU's College of Agricultural, Human, and Natural Resource Sciences. "Scientists like Brandon are advancing the field by tackling its toughest challenges and delivering solutions that make a real difference for beekeepers and growers nationwide.