Notes from the Field: Moses Coulee

Rochelle, Jeff and I  headed out to Moses Coulee to catch bats in the shrub-steppe. The primary goal of this trip was to be guest researchers for an Urban Conservation course through the Doris Duke Conservation Scholars program. We took the students out mist-netting and showed them what it was like to be a real bat researcher. Even though time was limited, we had success the first night out! We caught two amazing species, the Canyon bat (Parastrellus hesperus) and the Townsend’s big-eared bat (Corynorhinus townsendii). This group of students was extremely interested in many aspects of bat research: from managing museum collections, to emerging research and basic biology of bats.  

This excursion also allowed us to set up some of our new equipment, a triple high mist-net that Rochelle and I lovingly named “Monster”. We ventured out for a second night of mist-netting, “Monster” in hand,  with the optimistic hope of catching a Spotted bat (Euderma maculatum). We did not succeed in netting a spotted bat, but we did catch a Pallid bat (Antrozous pallidus) which was also very exciting! Overall this was a successful trip for us to see the diversity of species in a different part of the state and to help spread awareness about bat ecology, conservation and research.


Bat of the Week: Antrozous pallidus

Common name: The Pallid bat

Photo Credit: Top: Merlin Tuttle, bottom left: American Natural History Museum, bottom center:, bottom right: J. Scott Altenbach
Photo Credit: Top: Merlin Tuttle, bottom left: American Natural History Museum, bottom center:, bottom right: J. Scott Altenbach


Where to find them: This widely distributed species, along the west coast of the North America, has a range from southern British Columbia through Montana to central Mexico.

Roosting: The pallid bat roosts in a variety of places but favors rocky outcrops.  They can be found roosting in anything from caves, rock crevices, mines, hollow trees, to buildings. At night they choose temporary roosts for resting between feeding bouts that are near, but different from, day roosts.

Diet:  A. pallidus is an insectivorous bat and has a unique foraging pattern among North American bats. They fly very close to the ground, then dip down to grab ground-dwelling prey. This bat has extremely good hearing  and the foraging strategy allows bats to use passive hearing to find prey moving on the ground. They may also make contact with the ground to grab larger prey. They also forage for insects among leaves and flowers. Additionally, they will take smaller prey in the air using echolocation. Pallid bats take larger prey back to their roosts and remove hard parts, such as wings, legs, and heads, from prey before consuming them.

Unique traits: Pallid bats use vocalizations to locate other members of their group. There are four main call types used to communicate with other individuals: a directive call  is used to find another individual, a call consisting of squabble notes tells bats how to space themselves when roosting, a buzz call used for intraspecific encounters, and ultrasonic  pulses for  orientation and communicating exploratory activity to other individuals. Another unique trait is how agile they are on the ground; they are good at crawling and climbing.

Recent research:  Barber tested if A. pallidus is able to process two different streams of auditory information simultaneously while hunting. This research shows that pallid bats behaviorally modulate their echolocation calls to be able to switch focus between two streams of auditory information, but cannot truly dually orient themselves via echolocation and listen to insect movement. (Barber et al., 2003)

Information from


Bat of the Week: Nyctimene albiventer

Common name: The common tube-nosed fruit bat

Photos are not of N. albiventer, but of related species. Photo credit: Right: Bernard Van Elegem, top left: Alexander Riek, bottom left:
Photos are not of N. albiventer, but of a closely related, similar looking species. Photo credit: Right: Bernard Van Elegem, top left: Alexander Riek, bottom left:

Where to find them: Halmahera Islands, Banda and Aru Islands, Bismarck Archipelago, Moluccas, New Guinea, Admiralty and Solomon Islands and the Cape York peninsula of Australia.

Roosting:  The common tube-nosed bat roosts individually on the trunk of trees or branches. Their wings are covered with irregularly sized and spaced, yellow spots that act as camouflage while they roost.

Diet:  N. albiventer is primarily frugivorous, however it may also eat nectar and insect remains have been found in the stomachs of a few specimens. To eat fruit, the bat will hang horizontally biting off small chunks of fruit.

Unique traits: This bat has a unique face, with long tubular nostrils and very large eyes. The function of the tubular nostrils is unclear, however they could aid in finding fruit through olfaction or be used in the production of sound as the nasal tubes stretch and vibrate when the bat emits a high whistling call.

Recent research:  N. albiventer has been of interest in various feeding studies. One study documents the fruit handling behavior in both Old World (Pteropodidae) and New World fruit bats (Phyllostomidae).  While there is variation in the fruit handling behavior among all bat in this study, N. albiventer primarily held fruit with their stomach as opposed to with their wings, like most New world fruit bats (Vandoros & Dumont 2004).

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Bat of the Week: Thyroptera tricolor

Common name: Spix’s disk winged bat

photo credit: Top left: Christian Zielger, top right: Brock Fenton, bottom left: Alan Henderson, bottom right:
photo credit: Top left: Christian Zielger, top right: Brock Fenton, bottom left: Alan Henderson, bottom right:


Where to find them: Southern Mexico to the South Eastern Edge of Brazil

Roosting: Spix’s disk winged bat roost in the partly unfurled leaves of trees of the genus Heliconia (palm). Their roost colony size is about 6. These bats change roosts often, every day or so, because as leaves mature they unfurl and are no longer habitable roosts.

Diet:  T. tricolor is an aerial insectivore, catching insects while in flight. It consumes about 1 gram of insects a day, including beetles and flies. 

Unique traits: At the base of their thumbs and ankles is a disk-shaped suction cups that they use to cling to the  Heliconia leaves in which they roost. One of these disks is strong enough to support the bat’s entire weight. They also posses “warts” on their noses, it is hypothesized these “warts” are extra sensory organs.

Recent research:  T. tricolor uses call-and response systems to find group members. Flying bats can discriminate between the inquiry and response calls emitted by group and non-group members (Chaverri 2012).

Information from

Bat of the Week: Uroderma bilobatum

Photo credit: Clockwise from top left [Rich Hoyer][] [ARKiVE:Robin Monchatre] [Doris Potter]
Photo credit: Clockwise from top left [Rich Hoyer][] [ARKiVE:Robin Monchatre] [Doris Potter]
  • Where to find them: Southern Mexico to Peru and SE Brazil.
  • Roosting: To make their home, these bats bite along the main vein of the large leaves of palms. This causes leaves to droop and form a “tent”, which provides shelter for the bats, particularly from rain. They roost in colonies from 2 to 59 individuals and they roost tightly clumped together.
  • Unique traits: These bats are easy to spot; they have a white stripe above and below each eye and a narrow white stripe along their back.
  • Diet: They feed primarily on fruit.
  • Recent research: Coconut palms were introduced recently in the Neotropics and  tent-making bats have developed the ability to use them for roosting. These bats seem to be expanding their range following the expanded distribution of this exotic plant species and into human-modified areas.

Information from

Bat of the Week: Sturnira lillium

 Little yellow-shouldered bat

Photo credit: Clockwise from top left [ Merlin Tuttle] [] [] [Merlin Tuttle]
Photo credit: Clockwise from top left[ Merlin Tuttle][][][Merlin Tuttle]
  • These bats are frugivorous, primarily feeding on fruit from the Solanaceae family.
  • These bats often roost alone, but can roost with up to 10 members.
  • Bats have scent glands on the shoulder. Some say the scent smells like iodine, others say the scent is spicy.
  • They are very important in terms of seed dispersal since they eat a variety of fruits from a variety of plant families, not limited to Solanaceae. 

Continue reading “Bat of the Week: Sturnira lillium

Notes from the field: La Selva

Leith, Rochelle, and an adorable Ectopylla alba

La Selva has been a fascinating place to visit. While Rochelle and I both had impressions of what a tropical rainforest would be like, we were both amazed at the lush, complex habitat and the organismal diversity that goes along with it. For me, I learned an extensive amount, not only about the ecological dynamics in the wet rainforest, but also more about the diversity of bats. We had the wonderful opportunity to work with Dr. Gloriana Chaverri.  She gave us an opportunity to study the acoustic properties of neotropical bat distress calls, (primarily phyllostomids). Then, we conducted playback experiments to investigate how surrounding bats (intraspecifics and interspecifics) respond to these calls . In addition to our research, we were also busy working with Day’s Edge Production to produce a short film portraying the story of our research experience at La Selva. Check out the link below to see our video!