Understanding the Complexity of Little Brown Bat Summer Populations

North American bats have been experiencing unprecedented declines because of a novel disease called white-nose syndrome, wind energy conflicts, and likely because of declines in their insect prey. White-nose syndrome is a disease caused by a cold-loving fungus, and when hibernating bats are infected the fungus shows itself as a white fuzz on the muzzle, ears, and face of bats. When the disease hit eastern bat populations the evidence was clear, as hundreds of dead bats were found at the openings of caves that used to be home to thousands and millions of bats. In western North America, understanding when such a disease hits will be more challenging because many winter roosts house much fewer bats. For example, in Colorado, the largest winter colony of bats is approximately 600.

Because of a lack of large winter colonies, Colorado Natural Heritage Program zoologists Rob Schorr and Jeremy Siemers are turning their attention to monitoring summer colonies. Since 2014, Schorr and Siemers have been conducting mark-recapture studies of little brown bat (Myotis lucifugus) maternity colonies in northwestern Colorado. They have inserted passive integrated transponder (PIT) tags in >1,000 bats, and rigged their roosts with PIT-tag reading antennas to record the arrivals and departures over the summer. These data are valuable for estimating survival of bats and understanding fidelity to roosts.

This year Schorr and Siemers recruited two ambitious Colorado State University undergraduate researchers, Kira Paik and Toryn Walton, to understand what other roosts little brown bats use. Paik and Walton spent the summer tracking 22 little brown bats that were fitted with small radio-transmitters. They discovered that the adult female bats, despite traveling over 30 miles on their evening feeding travels, tended to return each night to roosts that are within a couple miles of the main maternity colony. This knowledge is extremely valuable for understanding where additional mark-recapture effort should be directed if biologists want to identify bat population trends.

Little brown bats after being tagged.

Siemers & Schorr marking little brown bats. 

Little brown bats flying around one of the maternity roosts.

Paik & Walton with the field vehicle for tracking telemetered bats.

Paik at the harp trap with a captured bat.

Walton tracking one of the telemetered bats.

2017 Colorado Rare Plant Symposium

Botanists and members of the Colorado Rare Plant Technical Committee (RPTC) were among the group of nearly 60 people gathered at Colorado College in Colorado Springs, CO, to attend the 14th Annual Colorado Rare Plant Symposium. The symposium is held each fall in conjunction with the Colorado Native Plant Society’s (CoNPS) annual meeting, and is hosted by the Colorado Natural Heritage Program (CNHP) and Denver Botanic Gardens (DBG).

Attendees included professional and amateur botanists with a common interest in Colorado rare plants and their conservation. This year Jill Handwerk (CNHP) presented data and photos of rare plant species known from southeast Colorado, along with the critically imperiled (G1) and federally listed plants species of Colorado. New this year was an afternoon review of the U.S. Forest Service (USFS) and Bureau of Land Management (BLM) sensitive species, led by Steve Olson and Carol Dawson, respectively. Additionally, Tim Hogan (CU Herbarium) provided herbarium specimens of the southeast Colorado rare species. The presenters encouraged participants to share their observations about the highlighted species and learn the latest information on Colorado’s rare plant conservation efforts.

Here are some highlights from the 2017 Symposium: 

New populations of rare plants reported in 2017 included populations of West Silver bladderpod (Physaria scrotiformis) and Gibbens’ beardtongue (Penstemon gibbensii).

Genetic studies continue to answer taxonomic and management questions for some of our state’s rarest species, including: boatshaped bugseed (Corispermum navicula), Mancos Shale packera (Packera mancosana), Kremmling beardtongue (Penstemon penlandii), North Park phacelia (Phacelia formosula), in addition to Sclerocactus species of western Colorado and eastern Utah.

Habitat was protected by the Colorado Natural Areas Program for Pagosa skyrocket (Ipomopsis polyantha) with the purchase of 88 acres of occupied habitat. Pagosa skyrocket is endemic to the Pagosa Springs area and is federally listed as threatened.

Steve Olson (USFS) provided an update on upcoming changes in how the USFS regional sensitive species lists are developed. The USFS is moving towards Species of Conservation Concern which must focus on ecological conditions, and will be based on NatureServe G and S ranks. Existing Sensitive Species will remain in effect until new management plans are developed for each forest.

Additional afternoon presentations were as follows: Raquel Wertsbaugh with the Colorado Natural Areas Program (CNAP) discussed the recent incorporation of rare plants into the State Wildlife Action Plan and the implications for land management and conservation. Jessica Smith (CNAP) discussed the implementation of monitoring for Pagosa Skyrocket at the newly acquired state owned property. Susan Panjabi (CNHP) gave a brief presentation regarding recently developed Best Management Practices for Roadside Rare Plants, and an overview of the online Colorado Rare Plant Guide. Moderator Jennifer Neale (DBG) concluded the symposium with a discussion of how we, as a group, can share our conservation successes with a wider audience.

For more information: 

All of the information from this meeting as well as previous symposia is available online at the Colorado State University, Colorado Natural Heritage Program (CNHP) website: www.cnhp.colostate.edu.

The Rare Plant Symposium is open to anyone with an interest in the rare plants of Colorado. For more information contact Jill Handwerk at jill.handwerk@colostate.edu or Jennifer Neale at nealejr@botanicgardens.org and check the CoNPS website (www.conps.org) for details as they become available about next year’s symposium.

Location of SE Colorado G2G3 plant species. 

Survey site for Pagosa Skyrocket. 

Pagosa Skyrocket.

Chiroptophilia - A Post-CNHP Adventure

By Savanna Smith
(former CNHP work study)

As a Chicago Botanic Garden Conservation and Land Management botany intern at the Shoshone Field Office of the BLM, my love for plants has grown exponentially this summer. I’ve gotten to know the best method for beating the seeds off a Purshia tridentata bush, smelled many a sagebrush, and puzzled over whether or not a Penstemon’s anthers dehisced from the center or the sides. However, I can’t deny my roots in the field of wildlife biology, which is what I studied as an undergraduate. As a climber, it seemed natural to be interested in bats since they often roost in the cracks and crevices only accessible to rock climbers. (For any other wildlife-enthusiast climbers out there, you should check out Climbers for Bat Conservation on Facebook, a cool citizen science project!) My undergraduate thesis research dealt with the acoustic side of bat science, but I didn’t participate in any of the field work for the data. So, you can imagine my excitement when I learned that I would get to assist in several bat-related projects this summer.

The first project involved setting up stationary acoustic bat detectors with Ross from Idaho Fish & Game - this work was conducted for the North American Bat Monitoring Program, a continent-wide protocol aimed at gathering data on the status and trends of bat populations across North America. After securing these detectors during the daylight, we waited until nightfall to conduct mobile acoustic surveys. This involves attaching a bat detector on top of the truck and driving at a constant speed for at least 25 km, all while recording the bats flying overhead. This was fun because I got to watch the calls coming in on a spectrogram in real time.

Last week, myself and other interns had the opportunity to attend a bat bioblitz - an event where scientists attempt to capture all the biodiversity in an area. We set up triple-high mist nets over the river and patiently waited for bats to fly in. We saw and recorded many bats, but only managed to trap two in the nets. Regardless, it was really cool seeing them up-close and learning how to take measurements. At our station, we captured an adult female silver-haired bat (Lasionycteris noctivagans) and a juvenile male Yuma myotis (Myotis yumanensis).

We camped out after the bioblitz and got a quick night of sleep before returning to the office for a day of caving in Gypsum lava tube, the second largest lava tube in the continental US! This was a new experience for me, and I enjoyed the pressing silence and impenetrable darkness that each bend in the passage concealed. In the tube, we found pack rats, a jackrabbit carcass, and even a few bat friends hanging out almost two miles into the tube! It was a great experience to put myself in such a different environment.

I’m thankful that this internship has allowed me to gain experience in a variety of areas, especially since bats are creatures I’ve been interested in for a long time. I only have six more weeks left here in Idaho, and I’m excited to see what’s next.

Sunset view before the mobile acoustic transect.

Adult female silver-haired bat. 

Juvenile male Yuma myotis. 

The entrance to Gypsum lava tube.

Jackrabbit carcass.

Kind of low quality photo of the inside of the tube - check out the multiple levels!