WEST GLACIER – Tabitha Graves can’t say this will be a bad year for huckleberries, even though four of the five sites she is monitoring in the West Glacier area show berry production is down 75 percent to 95 percent from last year.
But the fifth is showing the same number of berries as 2014, when a bumper crop was produced after a wet, cool spring.
And Graves, a research ecologist with the U.S. Geological Survey, doesn’t yet know what the huckleberry crop at higher elevations – where bushes are just popping out from under snow – will be like this summer.
"It could still be a great year if the berries at the higher elevations grow," Graves says.
The fact that she’s watching – and watching closely – means the day may come when she will be able to predict with some certainty what huckleberry lovers can expect.
Of course, the huckleberry lovers Graves is concerned with will never read her research or decipher the predictability maps she hopes to produce.
This is all about the bears. In Glacier Park, huckleberries constitute 15 percent of the diet of grizzlies and black bears.
If you can predict when and where huckleberries will be plentiful, you can predict where bears will likely be at that time.
In a Glacier National Park forest, just a short walk from her office near park headquarters, Graves has set up one site where it’s easy to show people how she and her collaborators are gathering data for their huckleberry research.
There, she kneels next to a plant that has more tent caterpillars chewing on its leaves than berries hanging from its branches.
She counts five caterpillars, and three berries, on the bush. In 2014, Graves says, a bush of this size would have had at least 20 berries, an estimate she also calls “conservative.”
“The tent caterpillars have added another wrinkle,” Graves says, “although they’re not after the berries, they’re after the leaves.”
The five sites being monitored in the area are among a dozen in the park. Here, the elevation is close to 3,200 feet, but Graves also has sites as high as approximately 6,500 feet – one near Sperry Chalet, where mountain peaks block sunlight for much of the day, and another on (how could she not) Huckleberry Mountain, which is in the open and exposed to much sunlight.
“Some years, the crop will be good in one place and bad in others,” Graves says. Her goal is to figure out why.
There are a ton of variables to track as the pilot program enters its second year.
Moisture is important, but not just how much. When it rains is a key, too.
“If you get a lot of rain when the plants are flowering, the pollinators don’t get as much done,” Graves says. “That’s true for the cherry crop in the Flathead, too.”
She’s still adding to the list of things that affect huckleberries – everything from canopy cover to growing degree days.
“Last year, at the higher elevations, we still had green berries when a freeze hit,” Graves says. “They never made it to ripe.”
Graves is expanding on research started by biologist Katherine “Kate” Kendall, who retired after 35 years of grizzly bear research and who Graves once worked for, and then replaced, in the USGS West Glacier office.
“Kate started monitoring the productivity,” Graves says. “Now we’re trying to understand the timing, and why there are more berries in different places at different times.”
For a fruit popular not just with bears, but birds and humans too, there has been remarkably little published research, Graves says.
“The phenology of huckleberries isn’t published,” Graves says, referring to the study of the plant’s life-cycle events, and how they are influenced by habitat and variations in climate. “There’s a lot of information, but it’s mostly in people’s heads.”
To aid the research, Graves has set up remote cameras at all 12 sites that snap pictures, from a distance of 18 inches, of huckleberry bushes four to five times a day throughout the growing season.
She can see them when they’re budding, see them when they’re flowering, see them at the “saucer” stage (so called because “they look like flying saucers,” Graves explains), see them when they resemble tulips, see them when the berries are green, see them when they’re ripe.
During the flowering stage, the cameras also capture the bumblebees that do the pollinating. Montana State University graduate student Amy Dolan is assisting in the study of the all-important pollinators.
“They hang upside down on the flower to get the nectar,” Graves says, and completes the birds-and-the-bees story of how the pollen is transferred, “which is what makes the seeds start to grow and the berries develop.”
The pilot project began last year during the bumper crop, which is why Graves knows that this year, one of her sites has just 5 percent of the berries that were produced last year, three more have just 25 percent, and one is humming along at last year’s rate.
This year, a student at Salish Kootenai College has established 10 huckleberry sites with remote cameras on the Flathead Indian Reservation, too, which will add to the data, and Graves hopes that’s just the start.
She'd like to have designated huckleberry bushes near trails in Glacier – aside from the one near her office, her sites are more difficult to get to – that citizen scientists can help monitor.
And eventually, she’d like to have between 100 and 200 remote cameras focusing on huckleberry bushes from Canada to the Missoula area.
“You get more variation across space,” Graves says, and the more data she collects, the better she’ll be able to predict where huckleberries are going to be each summer.
It will be valuable information for wildlife and public land managers, according to Graves. Huckleberry pickers, however, will have to do what the bears do: Find them on their own.
“People are pretty secretive when they find a good patch,” says Graves, who has no more intention of messing with them than she would a bear.