This series of entries will feature the Polar Bumble Bee Expedition, a trip headed by Drs. Hollis Woodard, Alan Brelsford, Jessica Purcell, Jeff Diez, and Michelle Duennes, along with myself (Kristal Watrous) and Bren Woodard. We are also accompanied by Sean Nealon, our super UCR PR guy. We are traveling north along the Dalton Highway, which parallels the Trans-Atlantic Pipeline in Alaska from Fairbanks to Deadhorse. Our goal is to collect bumble bees to understand how they’re being impacted in the Arctic by climate change. For this multifaceted project, we’re doing voucher collection (data points for which species are where), pathogen characterization (involving collecting bee guts and later IDing pathogens), plant sampling (which plants the bees are visiting and what resources they offer), and hopefully some data on energetics as well. Our trip will take 16 days total, and will cover 980+ miles.
Day 1 (June 28) - the team met up in Fairbanks, marveling at the late sunlight and warmth. We ate some delicious food, drank some beers, and talked logistics for picking up our expedition vehicles the next morning.
Day 2 (Field day 1) - Fairbanks to Arctic Circle, June 29
We picked up our beehicles, BeeHemoth and BeeSpedition (yes, we really are that nerdy). We stocked up on last minute supplies, including a stop at Starbucks and Thai food for lunch from a pink food trailer along the roadside. Then we were finally on the road out of Fairbanks. The landscape was beautiful and lush with vegetation, which was a welcome sight coming from the drying landscape of Southern California in early summer. We drove through mixed birch-spruce forests, then finally were on the Dalton Highway!
More driving and we crossed over the Yukon River, which is the third longest river in North America. Immediately across the river we stopped to refuel, and spotted our first Dalton Highway bumble bees on fireweed!!! Then we stopped at Finger Mountain where we got our first taste of arctic vegetation. We continued driving to the Arctic Circle, where we set up camp. The longest outbound day of driving is under our belts, and we’re in the Arctic Circle!
A couple of weeks ago we were back on the road for a more local info-gathering outing, this time for a CA-based desert day trip. Hollis and I drove out to the Desert Research and Extension Center in Holtville, CA. There we learned about the common crops in the Imperial Valley (sudan grass, melons, alfalfa, wheat, etc.) and some of their management strategies and questions being addressed at the REC. The desert poses some obvious challenges to growing crops (water, obvs), but the energetic and physiological constraints placed on crops and their pollinators by the dry landscape are still unexamined in a lot of systems. This is something I’m mulling over, and hope to revisit.
Also, there are burrowing owls at the REC!
After our tour of the Desert REC we headed over to Borrego Springs to check out the Steele/Burnand Anza-Borrego Desert Research Center, co-operated by UC Irvine and Anza Borrego Desert State Park (http://anzaborrego.ucnrs.org). This place is POSH. A former country club turned art gallery restored and turned into a research center, it is likely the only center in the UC system with a sunken bar and such fab architecture. While it no longer has the country club pool, the property abuts Anza-Borrego Desert State Park, the largest state park in California, making it a great base for desert research in this corner of the Coloradan (Sonoran) Desert. (Anza-Borrego DSP link)
With such great resources just a couple hours away, we’re definitely hoping to take advantage of these sites in the future.
Our last morning at SWRS. Corey & Jerry struck out on getting some larvae of Sphecodosoma and Calliopsis yesterday, so we opted to check out the site on our way out and hope for some nest-digging luck. We drove out to Animas and, following directions, parked near Sock and Shoe Road just past the upturned beer bottle as a roadside site marker. We found the site fine, complete with Sphaeralcea and Nama flowering and a few bees flying around. We had barely started looking for the nests Jerry found (marked with large rocks - nest relocation is like a treasure hunt!) when Hollis and a Mojave green rattlesnake mutually startled each other. After a couple minutes of racing hearts accompanied by intermittent rattles, our snake friend settled into hiding under a shrub and we happily gave it space. We found the bee nests, but unfortunately the Pogonomyrmex ant colony nearby was no more forgiving of our excavation attempts than they were the day before, trying to attack any soil-disturbing entity nearby.
Between the ants and the rattlesnake we decided the bee babies weren’t going to come easily, so we hit the road. We made a small stop outside Willcox to collect an early-instar canine to join the Woodard pack. Stripe settled in and napped many many hours on my arm. Thus the trip came to an end, complete with one final stop for Tucson Tamales before coming home.
In all, it was a very successful trip with larvae collected, collaborations made, selfies taken, and a new lab member.
Stay tuned for continued nest-finding, and the initiation of Hollis’ new house-turned-bee preserve.
Today we went in search of Lithurgopsis apicalis, a cavity-nesting bee in the family Megachilidae, which nests in the dried flower stalks of Agave palmeri. This bee’s nesting biology was recently reported in a paper by Jerry Rozen & Glenn Hall, based on their work near the Southwestern Research Station in 2014 (link here). With some encouragement from Jerry & Glenn, we decided to try to track down some Lithurgopsis larvae in the Agave stalks. Luckily for us, Bob Minckley joined us for the hunt.
Turns out Bob did his Masters looking at Xylocopa nest site preference in Agave stems and is quite proficient at cutting down the flower stalks. There was some blood involved, but ultimately we got Lithurgopsis larvae! One stalk we cut down had five nest cells we could see along one section. Rather than break it open in the field, we brought two sections of stalk back to the lab and got Jerry’s help to carefully break open the nest tunnels and retrieve the larvae.
We also got three larvae of a bonus bee, some Megachilid in the Osmiini, which also nested in one Agave stalk and constructed cell partitions with masticated leaf material. We’re not entirely sure what the bonus bee is since we didn’t find an adult, but will hopefully do some sleuthing and possibly follow-up nest hunting to figure it out.
I learned something important today: digging up (some) bee nests is hard work! With help from Jerry and Glenn Hall we accomplished our goal of collecting a few Hesperapis larvae. We also saw a neat snake. All in all, it was a great day.
Tomorrow we pack an axe and machete and head out on our own to look for Lithurgopsis larvae, taking our lead from Rozen and Hall's 2014 description of the nests within old agave stems (pdf here).
I have an immense amount of respect for the folks that take the time to study and describe the nesting biology of all of these wonderful and lesser-understood bees.
While we’re at the Southwestern Research Station we hope to: 1) get many bee larvae for our project, and 2) learn all we can from Jerry Rozen. Not only is he arguably the most knowledgeable larval bee expert around, he is also generous with his knowledge and witty to boot.
Jerry told us about Hesperapis rhodocerata, a bee in the basal Melittidae that he has found can remain in larval diapause for five years, waiting presumably for good conditions in order to complete their development and emerge collectively as adults. (Paper here: http://hdl.handle.net/2246/6646). Jerry showed us some H. rhodocerata larvae he has excavated, which are currently in the lab. These larvae are essentially in a physiological holding pattern while in diapause, but no one knows what environmental cue prompts these bees to complete their development and emerge simultaneously.
We then went hunting for Hesperapis trochanterata and their as yet undescribed nests. We found individuals foraging on Nama outside Willcox, but did not find any nests despite the promise of Dairy Queen treats for the finder of the first nest.
Tomorrow we’ll go see Hesperapis rhodocerata nests for ourselves. Still in store: the search for Agave-cavity-nesting Lithurgopsis. Stay tuned.
Hollis and I are taking a trip to the Southwestern Research Station in Portal, Arizona to join up with the Bee Biodiversity Initiative folks and collect some bees.
We are attempting to collect larvae from a broad range of bee taxa as part of a comparative study of larval development in bees. When we heard that the world's preeminent bee larvae expert, Dr. Jerome (Jerry) G. Rozen, Jr. of the AMNH, would be there, we knew we had to go.
On the way to Portal we stopped in Tucson and dug up some Diadasia rinconis (cactus bee; family Apidae) larvae from a large nesting aggregation. Patches of the aggregation were clearly done nesting, whereas others had newly-emerged females and many patrolling males. At this site we also saw large emergence holes of Centris pallida (pale digger bee; family Apidae) where the males actively dig down to extricate and mate with emerging females. Although we didn’t find any Centris nesting there, we did see many males patrolling for females nearby.
After a stop for tamales (so good) and a stop to meet some puppies (so cute) we were back on the road. We made it to SWRS despite a dust-storm closure of I-10, and are eager to learn all we can and dig all the nests while we’re here.