2019 Field Season Begins in Montana!

As usual the lab’s field season starts with a trip the Flight Lab at the University of Montana to work with long time collaborator Dr. Bret Tobalske. The main goal of this trip was to continue our work on heat dissipation during hovering in calliope hummingbirds (Selasphorus calliope), and to begin looking to extend our work on heat dissipation during flight to other bird species.

University of Montana Flight Lab

We began our work by measuring total evaporative water loss during hovering in calliopes. We actually started this work two years ago, but needed to increase our sample size. There is no simple way to make this measurement beyond getting birds to hover continuously in a metabolism chamber.

Metabolism chamber used in our study.

Once the bird is hovering evaporative water loss is measured using open-flow respirometry. As you might imagine this also requires a high flow rate. In our case 8 L/min!

The Sable Systems Field Metabolic System used in this study and our trusty iMac Pro running Warthog Software.

Once these measurements were made we switched gears and began experiments designed to help us understand how hummingbirds might behaviorally thermoregulate to dissipate heat accumulated during hovering at high temperature. We were in luck because we were able to get some time in a temperature controlled room for a few days to do our work (thank you Dr. Zac Cheviron). Bret’s graduate student Tony Lapsansky collaborated with us on this project. Our experiment involved a large acrylic flight chamber, and we used two FLIR Infrared video cameras to track perching and hovering surface temperatures over a range of environmental temperatures. We also recorded each trial using GoPro Hero 6 cameras that will be used to assess kinematic changes in hovering flight that might occur across temperatures.

Short video of one of our temperature trials.

Overall the trip was quite productive and we were really pleased with the quality of our data. Next, in about a week, we will be off to Chiricahua Mountains in southeastern Arizona and the Southwestern Research Station!

New Group of Undergraduate Researchers Join the Powers Lab

The Powers Lab is pleased to welcome three new undergraduate researchers to the fold this Spring!

Elliot Shannon is a sophomore biology major from Ridgefield, WA. His core project for the next year will be a study of whether or not hummingbirds selectively choose cool microclimates to dissipate heat after hovering in high environmental temperatures. The work will be conducted in the Chiricahua Mountains of SE Arizona. Elliot will be funded by the Richter Scholar Program at George Fox University. Welcome Elliot!!

Elliot Shannon

Nathaniel Shiiki is a junior biology major from West Linn, OR. Nathaniel’s core project will be a study of daytime temperature variation in natural perching microclimates used by hummingbirds throughout the day. This work will also be conducted in the Chiricahua Mountains of SE Arizona. Nathaniel will be funded by the Richter Scholar Program at George Fox University. Welcome Nathaniel!

Nathaniel Shiiki

Tiffany Regier is a freshman biology major who will be working on a variety of small projects including Arctic Tern energetics (collaboration with Dr. Hugh Ellis, University of San Diego) and validation of some changes to our open-flow respirometry protocol. Welcome Tiffany!!

Tiffany Regier

Powers Lab Travels to SICB 2019 in Tampa, FL!

The Powers Lab made their annual trek to the Society for Integrative and Comparative Biology meeting held this year in Tampa, FL. It was a light year as only three presentations were connected to the lab. Don gave an oral presentation on the use of shallow torpor by hummingbirds which was a collaborative work with Dr. Anusha Shankar (Stony Brook University) and Dr. Catherine Graham (WSL, Switzerland). Undergraduate researchers Natalie Amodei and Sarah Thompson presented posters on their projects. Natalie presented data on the effectiveness of evaporative heat dissipation during hovering at high temperature in hummingbirds, and Sarah presented on day on daytime weight management by hummingbirds. Both Natalie and Sarah did an amazing job! Former Powers lab undergraduate researcher Sean Powers, currently a Ph.D. student at Virginia Commonwealth University, also presented his work on invasive moths. Overall it was great meeting!

  • Don giving his talk on hummingbird torpor!

New Study on Range-Edge Lizard Energetics Published in Collaboration with the Powers Lab

Today a study was published in the journal Copeia detailing how lizards at the cool northern edge of their range energetically manage in an excessively cool climate. The results of this study could provide useful information regarding lizard range shifts resulting from climate change. Lead author of the study was Sean Powers (yes, a Powers lab progeny) who is currently a Ph.D, student at Virginia Commonwealth University. Click here to download the paper.

Lab Heads to the Southwestern Research Station in Arizona

The Powers lab collected data on hummingbirds for nearly a month at the Southwestern Research Station (SWRS) from the latter part of May to late June. Collectively we gathered data on nighttime body temperature management, daytime body mass management, and evaporative heat dissipation during hovering. Collaborator Anusha Shankar (Stony Brook University) and Sarah arrived two weeks before the rest of us to finish up measurements showing use of shallow torpor by hummingbirds. Once Don and Natalie arrived measurements of daytime body mass management and evaporative heat dissipation began. While the evaporation measurements were less successful than we hoped, we still ended our time at SWRS with tons of good data.