05/19/2013 11:56 am ET Updated Dec 06, 2017

Boulder County Bees Slow To Swarm This Spring

Longmont's Tony Lewis was on his way Thursday to collect a bee swarm at a home in Westminster when he was asked the question that has beekeepers buzzing this spring.

Where are all the swarms?

"I got my first swarm call about three days ago, and this is only my third or fourth call of the season," said Lewis, who does free bee swarm removal through

"By now I have usually had 50 or 60 calls," Lewis said. "A couple years ago, I was getting 10 to 15 calls a day."

Boulder's record April snowfall of 47.6 inches, followed by another foot of snow and record low of 17 degrees at the start of May -- has triggered some seasonal anomalies. Those include a late crop of dandelions, stunted tree bud development and, so far, a near-swarmless spring.

The phenomenon of honey bee swarming, most typically seen in the Boulder County area between April 15 and May 15, is triggered by the bees' wintering space becoming overcrowded and is a natural step in the bees' reproductive process. The presiding queen leaves the hive, taking roughly half the hive population of worker bees with her, forging a new colony. The bees remaining behind then create a new queen, in her place.

But if a hive has not thrived to the point where crowding exists, or if the bees know that the sources of nutrition they depend on don't exist at adequate levels, either factor can affect the timing and level of swarming that will be witnessed.

Symptomatic of a larger pattern

"I have been catching swarms for about 15 years on the Front Range, and what I can say is that they are three weeks late," said Corwin Bell, founder of He advocates an approach in which backyard beekeepers consider themselves "bee guardians," and he emphasizes a naturalistic, non-interventional approach to the hobby.

Recent trips Bell has made to Paonia and Carbondale, he said, show a similar pattern around the state. He said the state's wintry introduction to spring is a clear factor in the bees' reluctance to swarm.

"If you drive through Boulder, you'll notice there are no blooming trees," Bell said. "Everyone is saying they are just late to bloom. But if you look at their buds, they got hit by that last cold spell; they're not going to bloom."

Miles McGaughey, president of the Boulder County Beekeepers Association, keeps from 75 to as many as 350 hives of differing varieties at his Longmont property. He has collected only a handful of swarms this year but points out that the phenomenon of bee swarming is "an iffy deal" in the best of times.

"It's a timing issue with bees," McGaughey said. "They swarm when conditions are really prime for survival of the swarm that is leaving. They try to do it when there's lots of resources available, which around here is fruit bloom and dandelions, both of which were significantly delayed this year, and in the case of the fruit blooms, totally annihilated.

"And because of that there is just a high probability that many bee hives will not swarm, and those that do should swarm significantly later than last year."

Tom Theobald, owner of the Niwot Honey Farm, is in his 38th year as a beekeeper.

"If we're going to have swarming, it's likely to commence in the next week or two because we've had one of the best dandelion blooms in years, and that's a major source of nectar and pollen for the bees," said Theobald, a founder of Boulder County Beekeepers. "We look at that (the dandelion bloom) as the end of winter. The colonies who are better able to respond will now be getting crowded."

Colony Collapse Disorder

The swarming discussion takes place against the backdrop of the ongoing conversation concerning Colony Collapse Disorder, the mysterious crisis first reported in 2006. That's when commercial beekeepers started to notice large-scale deaths of honey bee colonies throughout the United States and around the globe.

Mortality rates for commercial beekeepers, according to a report released last week by the U.S. Department of Agriculture, have run as high as 33 percent from 2006 to 2011, with some anecdotal reports by beekeepers claiming a 90 percent loss of their managed hives.

The USDA report examined a wide range of factors, including the role of a parasitic mite called Varroa destructor, which has often been found in decimated colonies, as well as the widespread use of pesticides, including neonicotinoids.

However, the report stated, "While a number of potential causes have been championed by a variety of researchers and interest groups, none of them have stood up to detailed scrutiny. Every time a claim is made of finding a 'smoking gun,' further investigation has not been able to make the leap from a correlation to cause-and-effect."

It went on to state, "Researchers have concluded that no one factor is the cause of CCD. Most likely, CCD is caused by multiple factors. It is not possible to know at this time if all CCD incidents are due to the same set of factors, or if the factors follow the same sequence in every case."

Bell, who estimates recent hive loss in Colorado at between 50 and 60 percent, points to the European Union's vote late last month to ban the use of three neonicotinoids on crops attractive to bees for a two-year period, starting Dec. 1.

"They need to pass it here," Bell said. "There are a whole bunch of lawns and gardens that are using those, and the (resulting) large hive loss has added to the less swarming that we're getting."

Theobald, among those who unsuccessfully argued before the Boulder County commissioners for a neonicotinoid ban more than a year ago, said, "We are faced with some very serious problems, and the systemic pesticides are at the root of what has been presented as a great mystery.

"But if you look closely at the science," Theobald said, "most of the problems can trace their origin to the damage being done by these systemic pesticides.

"They are very, very damaging, and until we change the environment in which we're trying to survive, I don't see any improvement."

Contact Camera Staff Writer Charlie Brennan at 303-473-1327 or

Have a swarm?

Bee swarm hotline: If you find yourself with an unwanted swarm of bees on your property -- they usually cluster in the size of a football -- you can have the swarm safely removed by calling the Bee Swarm Hotline at 720-443-2331.

Read the U.S. Department of Agriculture's May 7 report on Colony Collapse Disorder: ___



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