Bumblebees in a changing world

Written July 24, 2013, published in late July 2013

In mid July, Dr. Jamie Strange, USDA-ARD Logan Bee Project, who studies bumblebees, taught a half day workshop on bumblebees and a seminar on pollinator declines across North America at Ft Clatsop, Lewis & Clark National Historical Park. More than one dozen people spent an afternoon learning how to work with bumblebees in the field, including safe handling (hint: clear plastic vials, a net and an ice box), how to identify local species in the field, and life cycle information. Participants included park and refuge staff, interns, a college professor, a beekeeper, and local natural history enthusiasts, all of whom share an interest in pollinators and bees. 

Dr. Jamie Strange talking about key bee identification features before sending the class out to catch bees. Julie Tennis, seated facing him, is a local beekeeper. Photo by Kathleen Sayce.

There are fifty species of bumblebees in North America, from Mexico to the northern boreal forests across Alaska and Canada, at low to high elevations, and thirty-eight species in the continental United States. Bumblebees form two distinct populations, living in the east or the west, with a few small areas where some eastern and western species overlap, such as the Black Hills of South Dakota. All overwinter as young queens, who form their own colonies each spring or early summer. In the late summer, virgin queens and males emerge; after mating, queens hibernate for the winter. Only the young queens overwinter; old queens, workers and males die each fall. Bumblebees can sting without dying, unlike European honeybees, but they tend to be placid, calm bees, and rarely sting even when severely provoked. 

As the initial orientation ended, the sun came out and the bees and novice bee collectors immediately went active at Netul Landing, where the class was held out of doors. Five species of bumblebees were collected in less than twenty minutes; many other bee species were seen, including leaf cutter bees and European honeybees, along with butterflies, dragonflies, wasps and other insects. Dr Strange had predicted that Bombus caligulinosus, obscure bumblebee,  would be the common species for the day, but to his pleased surprise, another normally rare species was almost as common, B. californica, California bumblebee. Also found were B. mixtus, fuzzy-horned bumblebee,  B. vosnesenskii, yellow-faced bumblebee, and B. flavifrons, yellow-fronted bumblebee. Bumblebee species emerge at different times of the year; some come out of hibernation in warm early spring weather, but midsummer is a good time to see most of the local bee species. 

As nets were gently maneuvered to capture bees, discussions continued about bee life cycles, when different species are active, and how to promote bees in home gardens: plant bee food plants and house bumblebees.  These bees often use abandoned vole tunnels in the ground, and in the wet Pacific Northwest, may also occupy tree holes, holes in eaves, walls or birdhouses, which led to a discussion on how to remake birdhouses for bees: Small entry holes, under ¾ inch diameter, and filling a bird  house with loose dry moss may help encourage bumblebees to nest in birdhouses. 

A freshly caught yellow-faced bumblebee, Bombus vosnesenkii, a still-common western bumblebee.  Photo by Kathleen Sayce.

Vials with bees were chilled for a few minutes to slow them down, after which they could be handled easily. No one was stung, and except for a few bees that were preserved for study, all the bees survived.  We got close looks at the five species that were active that day, and then watched as one by one they warmed up and flew away. 

That evening Dr. Strange gave a talk on pollinator declines across North America. Bees, butterflies, bats, and birds that pollinate flowers have all experienced declines in their numbers in the past couple of decades, throughout the continent. In many cases, specific pollinators have disappeared from sites, to be replaced by other species. The reasons are complex, but loss of habitat is a recurring cause. Pesticides and introduced diseases and pests also play parts. More than thirty percent of European honeybee hives die each winter. Over last winter, the average across North America was thirty-two percent.  

Vials and cold box, ready to chill bees for a closer look. Photo by Kathleen Sayce.

Home gardeners can help with foraging and nesting habitat for bees. We have many species of native bees, some of which nest in the ground, some in hollow woody stems, some in wood piles. All bees feed on flowers, eating both nectar and pollen. Planting good bee flowers, like sages, mints, penstemons, clovers, native perennials, and even common yard weeds helps our bees.  Avoiding insecticides, especially neonicotinoids, which are especially toxic to bees, is important. In a recent incident in Wilsonville, Oregon more than fifty thousand bees were killed after flowering linden trees were sprayed with a neonicotinoid pesticide to kill aphids. No one got up that morning and said 'I'm going to kill bees today,' the massive bee deaths were unintended. It may take years for the local population of bumblebees to recover. 

Dr. Jame Strange and Nancy Holman look at two very different bee species. Between them is Jamie's traveling bee specimen box, with nineteen North American bumblebee species. Photo by Julie Tennis.

Jamie Strange's research includes regular resurveys of sites to see how bee populations are maintaining themselves. He looks at low and high elevation species, studying their response to climate change. Some species are moving up in elevation. Others are dispersing to new habitats. More often, formerly common species vanish, to be replaced by others. A rare bee with limited geographic range died out in the past decade, and a more common bee took its place. 

There are websites that promote bee and pollinator diversity. Pollinator Partnership is located at http://www.pollinator.org, where a field guide to western bumblebees can be downloaded, or a print copy purchased. Xerces Society is one of the oldest insect diversity support organizations; it began a couple decades ago in Portland, Oregon; website http://www.xerces.org. These are just two of several pollinator resources on line. 

In my own garden, I plant more native flowering plants every year. Now I'm going to focus more on those flowers that bees feed on. And the next time we make birdhouses, we'll modify a few just for bumblebees.

Update on beach trash:  something is missing!

Written July 6, 2013, published mid July 2013

A few years ago I wrote about numerous yellow rope pieces found on local beaches during trash cleanup days. These yellow ropes were escaping from long line oyster operations after harvest. The ropes were cut between each cluster of oysters as the lines were pulled onboard oyster boats, then the oyster clusters were hauled to opening houses, where each cluster was taken apart and the oysters opened. Yellow rope sections were typically fourteen to eighteen inches long, and were removed from the waste shell, but not all were collected. Pieces in shell piles often ended up back in the bay a year or two later, spread on seed catching beds ahead of natural set of oyster larvae in late summer. From there, yellow ropes floated everywhere:  around Willapa Bay, out the entrance to the ocean beaches, and up and down the coast. Yellow rope has been seen on beaches north of Grays Harbor and south of the Columbia River. 

Piles of plastic materials waiting for recycling, yellow lines in the foreground, and bundles of black plastic mesh bags in the background. Photo by Kathleen Sayce

The oyster industry didn't realize how widespread these rope pieces were on local beaches. Once they realized this, they made some changes. First, several kinds of natural fiber ropes are being tested, including manila and cotton. With natural fiber ropes, they can continue to cut each cluster, and not worry about where the pieces go. Second, many growers began hauling the yellow plastic ropes with oyster clusters intact on board without cutting them up. The used ropes are bundled for disposal right on the boat and the oysters are pried off. The oyster crews also bundle the black mesh bags after seed oysters are removed, so that these too can be hauled out of the bay. 

Bundles of used long lines from oyster beds, coiled and waiting for recycling at an oyster opening house on Willapa Bay. Photo by Kathleen Sayce

On the beaches, the difference in just three years is amazing. During beach cleanups, like the Fifth of July beach cleanup day organized last week by Grassroots Garbage Gang, people used to pick up thousands of pieces of yellow rope. It was normal to find one piece of yellow rope in the tide line every five to ten feet on the ocean beach. Now there's probably one piece every thousand feet or so. That doesn't sound like much, until you think about the tons of other trash those folks are picking up. Bending over one to two hundred times per thousand feet to pick up short pieces of rope sounds tiring just writing about it. 

Other changes in beach trash include a slow shift in fireworks components to more cardboard and paper and less plastic. This is a very important, positive change. Small pieces of plastic are often overlooked, and quickly break into even small pieces, which become biologically active as they break down to microscopic sizes. Fireworks are intended to be destructively ephemeral, so there's no reason for them to be made of long lived plastics. Picking up trash this year, I saw that small parachutes are made of cotton string, paper and cardboard, where five years ago the cardboard section might have been plastic. There's also less plasticized paper, and more glossy paper. Small box fireworks that fountain into the air no longer have plastic tops or bases. I've picked up hundreds of those tiny black cones and tubes in the past from one small box of 50 or more individual chambers. It's a big change, and a welcome one, to see that these fireworks are now made of cardboard and paper. 

There's also been a positive shift in beach partier habits:  More people are picking up their own trash. Wonderful! We want this to continue, and we are trying to make it easy for visitors. Dedicated volunteers hand out bags on the Fourth of July at major beach approaches. Dumpsters are located on beach approaches with banners, reminding people not to bury or burn trash, but to collect and dump it. We treasure our beaches, and slowly, we are teaching our visitors to do the same. 

Post-tsunami debris still comes ashore regularly. The huge influx of large foam chunks last year has been replaced by a steady trickle of water bottles and other containers, wood building debris and the occasional boat. Many portions of our beach have dedicated volunteers who check their sections weekly; they pick up tsunami debris as it comes ashore. 

If you are looking for regular exercise for the good of the beach, get your own quarter mile or half mile stretch. Hundreds of people help on the big cleanup days, and volunteers to help coordinate this event are always needed.  For information about joining Grassroots Garbage Gang, or get your own section of beach, contact Shelly Pollock, phone 642-0033, email shelly@ourbeach.org.