ECOLOGICAL DEVELOPMENTAL

BIOLOGY IN A DANGEROUS WORLD –ADAPTIVE RESPONSES OF AMPHIBIAN

EMBRYOS

Eggs are tasty, nutritious, and often eaten. Butembryos are not all as defenseless as we once thought.Faculty associate Karen Warkentin, supported by a grant

from NSF, has shown that red-eyed treefrog embryos(Agalychnis callidryas) hatchrapidly, up to 30% early, to es-cape from risks as diverse aspathogenic fungus, egg-eatingsnakes, and drowning. Similarembryo responses have sincebeen found in five other familiesof amphibians, as well as fishesand spiders. Members ofWarkentin’s laboratory are exam-ining the mechanisms underlyingembryo responses to risk, as wellas their evolutionary history andecological implications.

Premature hatching of red-eyed treefrog embryos is stimu-lated by the vibrations induced during predator attacks onegg clutches. Ph.D. student Michael Caldwell, working incollaboration with Warkentin and engineer Greg McDaniel(BU, Aerospace and Mechanical Engineering), is studyinghow embryos are able to distinguish vibrations indicativeof danger from those caused by benign disturbances suchas tropical storms. They are recording vibrations from eggclutches during predator attacks and other disturbances tocharacterize the information detectable by embryos, usingvibration playback experiments to assess characteristics ofvibrations to which embryos respond.

How did risk-induced hatching evolve? Post-doc-toral fellow Ivan Gomez-Mestre is comparing risk-inducedhatching in red-eyed treefrogs and six of their close rela-tives. The field work for this project,funded by the NationalGeographic Societyand Boston University, has taken him

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Boston University • Center for Ecology and Conservation Biology • Winter 2005

CECB UPDATEGREETINGS FROM THE CECB DIRECTOR

A predator of frog eggs... ...caught in the act.

Dear Friends and Colleagues,I am pleased to send you a copy of the 7th annual

edition of CECB UPDATE, highlighting activities of someof our faculty associates and students over the past year.

New research grants and awards to faculty, post-docs and graduate students attest to an increased focus oncross-disciplinary, collaborative research. This edition pro-vides a glimpse of some of the exciting cross-disciplinaryprojects that are underway in such places as CostaRica, Indonesia, Malaysia, as well as here in theUnited States. For example, CECB faculty associ-ate Karen Warkentin has embarked upon a fascinat-ing study that focuses on how red-eyed treefrogembryos are able to escape predation in tropicalrainforests of Costa Rica. Working with graduatestudent, Michael Caldwell, post-doctoral fellowIvan Gomez-Mestre, and Professor Greg McDanielfrom BU’s Department of Aerospace and Mechani-cal Engineering, Warkentin’s interdisciplinary teamis exploring how natural and artificial vibrationsinfluence the escape behavior of these frogs.

Another CECB faculty associate, Paul Bar-ber, has recently embarked upon an excitingproject in Indonesia, that includes a team com-prised of minority undergraduates, graduate students, andIndonesian scientists to investigate the origins of marinebiodiversity. CECB post-doc Nick Hristov has joined a teamof ecologists, computer scientists, mathematicians, and en-tomologists, who are investigating the ecological and eco-nomic role of Brazilian free-tailed bats in agroecosystems.

Our Tropical Ecology Program continues to groweach year, where many of our best students spend a semesterabroad in Ecuador. We anticipate increased interest in thisprogram in the coming years with the recent release of along-awaited recruitment video.We are also looking forwardto the improvement of laboratory and housing facilities atthe Tiputini Biodiversity Station in Ecuador, through arecently awarded NSF grant.

We continue to welcome your financial support,especially for student research projects.

Sincerely yours,Thomas H. Kunz, Director

BARBER SEEKS TO INCREASE

DIVERSITY OF FUTURE SCIENTISTS,WHILE STUDYING BIODIVERSITY

Although persons of African American, Hispanic,or Native American descent comprise over 26% of the U.S.population, only 13.5% of undergraduate students graduat-ing with science or engineering degrees are under-repre-sented minorities. Fewer still (6.3%) will graduate with aPh.D. in the sciences. There are many obstacles thatcontribute to this pattern,but lack of first hand experiencewith research and scientific inquiry are among them. Thislack of exposure is particularly acute in the marine sci-ences, as many inner-city youths may have very limitedexposure to marine environments.

To address some of these issues, a new researchopportunity funded by the National Science Foundation,

“The Diversity Project” willcommence in the laboratoryof faculty associate PaulBarber, Boston UniversityMarine Program, in the sum-mer of 2005. This 10-weekeducational program for un-dergraduate students is de-signed to increase participa-tion of under-representedminorities in the biologicalsciences through an inte-grated field and laboratoryresearch experience. Stu-dents will join Barber,

graduate students, and Indonesian reef scientists in a 5-yearresearch initiative to study the origins of biodiversity on thecoral reefs in Indonesia. Indonesia is the center of theworld’s marine biodiversity with an unprecedented wealthof marine species, yet reasons for this pattern are notunderstood. Traditionally, it is believed that speciationresults from the divergence of populations separated by

physical barriers todispersal, such asrivers or mountainranges. Althoughthis model of spe-ciation works wellin terrestrial eco-systems, it is un-clear whether itapplies to marineenvironments, be-cause most marine organisms have a pelagic dispersal stagewhere larvae enter into the plankton and disperse greatdistances on ocean currents. As a result, it is believed thatthere are few barriers to dispersal in the oceans, and limitedopportunities for the formation of new species. High marinebiodiversity is thus a paradox.

Students in The Diversity Project will travel toIndonesia to participate in 2 to 3 week long researchexpeditions. Following the completion of field work, stu-dents will return to Woods Hole, and Barber’s laboratory.Students will receive training in state-of-the-art moleculargenetic techniques, and will apply those techniques to theirrecently collected samples to determine whether oceancurrents in Indonesian Seas limit the dispersal of larvae,thus promoting diversification of this regional biota. Theresulting data will help improve an understanding of theorigins of marine biodiversity in Indonesia, as well as theconservation of this biodiversity. In the process, the pro-gram will provide an unparal-leled opportunity for under-represented minority studentsto participate in both field andlaboratory research,thereby in-creasing human diversitywithin the marine sciences.For more information pleasecontact Dr. Paul Barber atpbarber@bu.edu or visit thewebsite: http:/people.bu.edu/pbarber/MRE.htm.

ROSENTHAL CO-ORGANIZES SYMPOSIUM

At the 2004 Animal Behavior Society meeting held in Oaxaca, Mexico, faculty associate Gil Rosenthal co-organizeda symposium on “Environmental Impacts and Behavior” in collaboration with Salvador Contreras-Balderas (UniversidadAutónoma de Nuevo Leon). The symposium addressed the impact of species introductions and habitat alteration on socialstructure, foraging behavior, mate choice, and communication. In a disturbed environment, the most immediate and visibleresponses are often behavioral. Environmental changes also severely impair critical behaviors even if they have no detectablephysiological or toxicological effect. Conversely, human-induced disturbances can be powerful, if unfortunate, experimentalmodels in behavioral ecology. The symposium highlighted the importance of behavior to conservation, and underscoredthe complex ecological and evolutionary effects surrounding behaviorally-mediated responses to disturbance.

A stomatopod, Gonodactylussmithii. Photo: Roy Caldwell.

Reef flat, Banaken Island, Indonesia.

Ph.D. Student Joshua Drew,on a dive.

NEW TITLES BY CECB FACULTY

ASSOCIATESFarouk El-Baz is the editorof a new book entitled Wadisof Oman: Satellite ImageAtlas, which is based onsatellite image interpretationsof the dry valleys of Oman.It was prepared to identifyareas in Oman that are proneto flash floods. Identifyingthese areas may help preventdeath and property damageresulting from these floods infuture years. TheGovernment of Oman

requested the study to make its results widely available tothe general public. In Part One, two-page spreads with colorillustrations summarize the topography, structure, climate,wadis, flash floods and flash flood hazards in this semi-aridsouthern edge of the Arabian Peninsula. In Part Two, Omanis divided into 28 major drainage basin areas where detailsof the landscape and its influence on surface water flow andflash floods are illustrated by photos in full color, some asthree-dimentional images. An Index lists all valleys andtowns named in the satellite image atlas in both Arabic andEnglish.

A.H. Sutton, Lisa Sorensonand M.A. Keeley have re-cently published the 2nd edi-tion of Wondrous West In-dian Wetlands: Teachers’ Re-source Book. This teacher’smanual contains comprehen-sive background informationand educational activities re-lating to the ecology andconservation of Caribbeanwetlands. The book is al-ready available in Englishand Spanish, and is soon to

be published in French, thus covering the three mainlanguages of the Caribbean. The book is being distributedin conjunction with two-day Wetlands Education Work-shops held throughout the region. Companion materialsinclude a slide show, puppet show, poster, coloring book,conservation buttons, postcard, field trip notebook, inverte-brate identification chart, wetland bird identification card,and a duck identification card for hunters.

ADAPTIVE RESPONSES OF

AMPHIBIAN EMBRYOS CONT’D

from Costa Rica to Guatemala and Southern Mexico. He isalso building a molecular phylogeny of the group, in col-laboration with facultyassociate Chris Schneiderand John Wiens (SUNYStony Brook), to describethe evolutionary patternof risk-induced hatching.His data thus far suggestthat risk-induced hatch-ing is widespread in thegroup, and probably an-cient, but at least one spe-cies seems to have lost itsresponsiveness to snakeattacks, while still re-sponding to risk ofdrowning. Gomez-Mestre has also started abreeding colony of severalspecies of leaf frogs atBoston University, to examine the genetic basis of hatchingplasticity.

How ecologically important is risk-sensitive hatch-ing? Post-doctoral fellow James Vonesh is working inGamboa, Panama at the Smithsonian Tropical Research In-stitute, to examine the population-level effects of hatchingtiming. He will combine monitoring of natural breeding siteswith laboratory, mesocosm and field experiments, and math-ematical modelling to examine how multiple stage-specific(egg or tadpole) predators affect the survival of red-eyedtreefrogs.

How does the physical environment affect preda-tor-prey interactions? Ph.D. student Justin Touchon is study-ing phenotypic plasticity in eggs and tadpoles of the pantlesstreefrog, Hyla ebraccata. The arboreal eggs of this speciesare amazingly physiologically tolerant of desiccation. How-ever, drying alters both their hatching timing and their vul-nerability to insect predators.

Gomez-Mestre and Touchon are also collaboratingon a study of risk-induced hatching in vernal pool amphib-ians in eastern Massachusetts. These species are exposed towater molds that can grow over the clutches and kill theembryos. Interestingly, some are able to hatch prematurely,continue their development, and start eating the mold in re-taliation.

Experimental set-up in the fieldtesting egg predation (with

Warkentin in the background.)

BU’S TROPICAL ECOLOGY PROGRAM ENTERS 10TH YEAR

Students in BU’s Tropical Ecology Program (BU-TEP) experience first-hand life inthe tropics and are given the opportunity to conduct their own field research in someof the most diverse ecosystems on the planet. Now entering it’s tenth year, the BU-TEP continues to be highly successful, drawing students from BU and beyond. Stu-dents leave the program well-prepared for the next step in their professional careers.Here are some examples of what students are saying about the program:

“Learning is actually fun, I found myself doing more work than I was supposed to do. Itsolidified everything we have ever learned” --Davis Ogitani F’04

“We were able to take what was learned in the classroom and see it and experience it personally. It was the best experience of my life.” --Sydne Levine F’04

“I learned an incredible amount this semester about my-self, people, cultures and life.” --Lindsay Miller F’04

Specialization in Ecology and Conservation BiologyThe May 2004 Commencement ceremony marked thegraduation of 8 students with a Specialization in Ecol-ogy and Conservation Biology.

WHERE ARE THEY NOW? BU-TEP ALUMNI

Lydia Munger (Spring 1999) works as a Fishery Management Plan Coordinator for the Atlantic States Marine Fisheries Commissionin Washington, DC. She coordinates science and management activities for various Atlantic fish species and facilitatescommunication between scientists, managers, and fishing industry representatives. lydia_munger@yahoo.com

Dan Janes (Spring 1995) is a post-doctoral fellow at Harvard University, researching the evolution of sex chromosomes in birdsand reptiles. His office is in the Museum of Comparative Zoology. djanes@oeb.harvard.edu

Nathan Kraft (Spring 2000, TA 2002) is in his second year of a Ph.D. program at Stanford University in ecology and evolution,where he is studying plant community ecology and functional diversity. njbkraft@yahoo.com

Bridget O’Neill (Fall 1999) graduated from BU in May 2000 with a B.A. degree in biology. She worked for two years at theSchepens Eye Research Institute in Boston on diabetic retinopathy. She is currently pursuing a Master of Science degree inEntomology at the University of Illinois, Urbana-Champaign. boneill6@yahoo.com

Debbie Dalton (Spring 2002) graduated from BU in May 2003 with a B.A. degree in biology, specializing in marine science.For the past year and a half she has been working for NY/NJ Baykeeper as the oyster restoration project manager. She is alsoworking on her Masters in Education at Monmouth University. zstarli611@hotmail.com

Amy Turmelle (Spring 2001) graduated from BU in May, 2002 with a B.A. degree inbiology. She has since worked at the American Museum of Natural History in New York andthe University of Vermont. She is currently pursuing a Ph.D. at the University of Tennessee,studying population structure and epidemiology in bats. turmelas@hotmail.com

Luba Zhaurova (Fall 2002) graduated from BU in 2004. After interning at the Bureau ofLand Management, Lake Havasu, Arizona and the non-profit recycling organizationWasteCap of MA, she now works at the Walden Woods Project. luzha19@hotmail.com

Grasshoppers congregating on a leafat Tiputini Biodiversity Station.

A student uses the spotting scopeat the Canopy Tower at the

Tiputini Biodiversity Station.

A treefrog peaks its head out ofa bromeliad.

Stay tuned for a 10th Anniversary celebration ofthe Tropical Ecology Program!

NOW AVAILABLE ON DVD

Recorded in Ecuador by Boston University’svideographers, CECB, in collaboration with BU’s MediaGroup, has produced a 13-min promotional video thathighlights experiences of students who have participated inBU’s semester-long Tropical Ecology Program. This videotakes the viewer on a fast-paced visit to the varied tropicalenvironments of a rainforest (Tiputini Biodiversity Station),Andes Mountains, Pacific coast, and the Galapagosarchipelago. Individuals who wish to receive a DVD copyshould contact the CECB administrator at: cecb@bu.edu

TROPICAL ECOLOGY SCHOLARSHIP FUND

The Center for Ecology and Conservation Biology, incollaboration with Boston University’s Office of Developmentand Alumni Relations, continues its fund-raising campaign tosupport scholarships for undergraduates, graduate students, andpost-doctoral scholars to conduct research in ecology andconservation biology.

With your support, we can continue to train and fundstudents in conservation research worldwide. We invite you tocontribute to this worthy cause. CECB wishes to acknowledgeand thank the following individuals and organizations for theirgenerous support during the past year.

Stratosphere Club (≥ $50,000)Contributions at this level help us to acquire equipment as wellas fund graduate students and post-doctoral scholars.• The Lubee Bat Conservancy

Ecosphere Club ($10,000 - $49,999)One contribution of $10,000 will support a graduate student inthe tropics for one full year.• The Chiles Foundation• Bill Macauley

Canopy Club ($5,000 - $9,999)Gifts at this level will help us purchase equipment for research.

Director’s Club ($2,500 - $4,999)Director’s Club gifts will help us update facilities at the TiputiniBiodiversity Station.

Rainforest Club ($1,000 - $2,499)These gifts will help upgrade computers and library resourcesat the Tiputini Biodiversity Station in Ecuador.•Michael Pappone

Friends of CECB (up to $999)Friends of CECB provide general program support.• Todd Klipp, BU General Council• Marshall Sloane, BU Trustee

Sunrise, as seen from the canopy tower at Tiputini

NSF GRANT TO IMPROVE FACILITIES AT

THE TIPUTINI BIODIVERISTY STATION

A National Science Foundation grant for $215,000was recently awarded to Boston University to improve theresearch infrastructure and housing facilities at the TiputiniBiodiversity Station (TBS) in Ecuador. Developed as acollaboration between BU’s Center for Ecology andConservation Biology, Division of International Programs,and the Universidad San Francisco de Quito (Ecuador), TBSwas established in 1996 to support research and trainingactivities of scientists and students in a lowland Amazonainrainforest. Funds from this grant will support theconstruction of a new 3,000 sq. ft. laboratory, new housingfacilities for scientists, purchase of a new truck, andinstallation of a satellite uplink/downlink for Internet access.The new laboratory facililty will include an air-conditionedlibrary/computer room, enlarged common laboratory,seminar room, and research space for long-term researchers.These facililities will be available to Boston Universityresearchers and students, (including those in BU-TEP), andto scientists from other institutions.

Stable Isotope Laboratory Installs New Equipment

Stable isotopes are non-radioactive, naturally occurring varia-tions of elements found in nature, differing in the number of neutronsfound in the nucleus of atoms. Stable isotopes have a wide range ofapplications in ecology and conservation biology, including the analy-sis of paleoclimates, diets, food webs, nutrient and water flux in bothterrestrial and aquatic ecosystems, and for identifying sources of pol-lution and monitoring sites under bioremediation. This past June, theBU Stable Isotope Laboratory uncrated two new isotope ratio massspectrometers capable of analyzing isotopes of carbon, nitrogen andsulfur. Several benefits of these new instruments include reduced ana-lytical costs, improved turnaround times and an expansion in the oftypes of samples the lab can analyze. The mass spectrometers andperipherals in this laboratory were made possible by grants from theNational Science Foundation.

KAUFMAN PENS ARTICLE FOR

NATIONAL GEOGRAPHIC

CECB faculty associate Les Kaufman recently returnedfrom a field assignment with National Geographic to Fiji.Joined by photographer Tim Laman, Professor Kaufmaninvestigated the recovery of coral reefs from recent bleach-ing events caused by a rise in sea temperature. The result-ing expulsion of the endosymbiotic algae of corals leavesonly clear coral tissue. With only the white calcium car-bonate skelton beneath the polyps, the resulting coral ap-pears “bleached.” With sea surface temperatures reachingcritical highs throughout the tropics, it has become increas-ingly urgent to study these interactions. You can read thefull article in the November issue of National Geographic,or visit http://magma.nationalgeographic.com/ngm/0411/feature3/index.html for a summary and other features in thisstory.

Les Kaufman (left) and Tim Laman about to dive atCannibal Rock, Rinca Komodo Islands, Indonesia.

Photo by Zafer Kizilkaya

Bob Michener (pictured) has run the Stable Isotope Laboratory since its inception in 1989.

RESEARCH TEAM TO INVESTIGATE

THE ECOLOGY OF RABIES

Since the discovery of rabies in bats in the 1930’s,most research has focused on efforts to identify sourcepopulations, develop effective vaccines and prevent loss ofhuman life. Little research has focused on the relationshipbetween natural hosts, immune responses of hosts to rabiesinfections, or on geographic and species variation in rabiesvirulance. A new research program jointly funded by theNational Science Foundation and National Institutes ofHealth has begun to address questions about the ecology ofinfectious diseases. This program is supporting a newthree-year, $1.4 million collaborative grant awarded to theUniversity of Tennessee, Boston University, and the Cen-ter for Disease Control and Prevention to focus on theecology of rabies in two bat species of North America—the Brazilian free-tailed bat (Tadarida brasiliensis) and thebig brown bat (Eptesicus fuscus), both known to harborstrains of rabies virus. This project involves senior scien-tists, post-docs, graduate students, and technicians fromeach of the participating institutions. Senior scientists atBoston University include CECB faculty associates Tho-mas Kunz, Eric Widmaier and Michael Sorenson. Thisresearch team will investigate geographic variation in theincidence of rabies in these two species and will assessanthropogenic stress factors that may decrease the overallhealth and well-being of bats, which may in turn increasethe incidence of rabies in local populations. Kunz’s re-search will focus largely on field aspects of the study,including sampling populations for blood, saliva, and

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TESTING LIMITS OF COEXISTENCE INCRYPTIC BAT SPECIES

Graduate Student SusanMurray,, was recentlyawarded a National Sci-ence Foundation Doc-toral Dissertation Im-provement Grant to sup-port her research in Ma-laysia to test the limits ofcoexistence of two mor-phologically cryptic butgenetically divergent lin-eages of Old-World leafnosed bat (Hipposideros

bicolor) in Malaysia.Murray, a graduate student

of CECB Director Thomas Kunz, recently returned fromspending over 18 months in the field to collect tissue forgenetic analyses and to identify morphological, ecological,and behavioral traits that allow these two morphologicallysimilar taxa to co-exist in a Malaysian rainforest. She will beusing NSF funds to determine the population structure ofthese bats based onmitochondrial andnuclear DNA markers.As Murray notes, “Abetter understandingof the limits of coexist-ence may help eluci-date processes impor-tant in assemblage andcommunity structuringand why some assem-blages are more speciesrich than others.”

Susan Murray at work at her fieldsite in Malaysia.

Post-Doctoral and GraduateStudent Grants and Awards

Polly Campbell was presented with the Lubee Bat Conser-vancy award for the best oral paper presented at the 34th

North American Symposium on Bat Research in Salt LakeCity. The topic of her award-winning paper was“Ecomorphological divergence and ratios of coexistence inthe Cynopterus brachyotis species complex.”

Gloriana Chaverri was awarded research grants from theConservation Food and Health Foundation and the LincolnPark Zoo Field Conservation Fund to investigate “Geneticconsequences of a variable fission-fusion social system intent-making bats”

Tigga Kingston was recently awarded a grant from NationalGeographic Society entitled “Extinction risk assessments ina Paleotropical bat community,” and an Earthwatch YoungScientist Award in recognition of her research on batconservation in Malaysia.

Amy Mertl was awarded the Tony Swain Award for heroutstanding performance on the Ph.D. qualifying exam inthe Ecology, Behavior, and Evolution graduate program.

Susan Murray was awarded a National Science FoundationDoctoral Dissertation Grant to support her research inMalaysia on “Testing the limits of co-existence in crypticbat species.”

William Ojwang was honored with the newly created“Award for Excellence in Conservation Biology, ” inrecognition of his conservation efforts in Kenya. Theaward was created to recognize excellence in the executionof conservation science by graduate students who havecompleted their oral exams and are actively engaged infield work. Ojwang’s research addresses the impacts ofbiodiversity loss on ecological food webs, using the openwaters of Lake Victoria, East Africa, as a model.

Jonathan Reichard and Louise Allen were presented anaward for the best student poster presented at the 34th NorthAmerican Symposium on Bat Research in Salt Lake City.The topic of their award-winning poster was “That’s goodguano: Fertilization services of the Brazilian free-tailed batin south-central Texas.”

Old-World leaf-nosed bat,

Hipposideros bicolor.

BU-TEP T-SHIRTS AVAILABLE

CECB continues to sellT-shirts to promote and com-memorate the Tropical Ecol-ogy Program in Ecuador.T-shirts are currently on salefor $12.00. To order, pleasesend a check (payable toCECB) to the Center Admin-istrator, CECB, Boston Uni-versity, 5 Cummington Street,Boston, MA 02215. Be sureto include the size you wouldlike for us to send.

FOR MORE INFORMATION ABOUT ANY OF THE ITEMS IN THIS ISSUEPLEASE CONTACT CECB

*Mail: CECB, 5 Cummington St., Boston, MA 02215 *Phone: (617)353-6982 *Fax: (617)353-5383*On the web: http://www.bu.edu/cecb *E-mail: cecb@bu.edu

BRAZILIAN FREE-TAILED BATS AT CARLSBAD CAVERNS NATIONAL PARK

UNDER THE WATCHFUL EYE OF AN INFRARED THERMAL CAMERA

With a recent 3-year grant from the U.S. National Park Service, CECB Director Thomas Kunz and post-docNick Hristov are using an advanced infrared thermal camera to census Brazilian free-tailed bats (Tadarida brasiliensis)during their nightly emergence flights from Carlsbad Caverns in New Mexico. For decades, this colony, once estimatedto number upwards to several million bats, has provided a unique opportunity for thousands of visitors each year to

observe these winged mammals as they emerge nightly to feed on flying insects.The consumption of insects by these bats, in both natural and agriculturallandscapes surrounding the park, provides an important ecosystem service tomankind. According to the park’s Resources Management Plan, the evening“Bat Flight Program” is one its principal public attractions, second only to thecavern itself. Accurate estimates of the number of Brazilian free-tailed bats inCarlsbad Caverns remains a high priority to help inform park managers and thegeneral public of the importance of these bats to both natural and human alteredecosystems.

As noted by Kunz, “censusing this and other bat colonies with infraredthermal cameras is far superior to other methods that have been tried in thepast.” This high-tech censusing method allows frequent, accurate, and repeat-able estimates of the number of bats that emerge from the cave, independent ofcolony size and ambient light, while causing no disturbance to the colony. Thecensusing protocol involves: 1) passive detection of individual bats based onadvanced infrared thermal imaging, 2) recording real-time, high-fidelity digitalinfrared images, and 3) processing the recorded digital images into reduceddatasets that yield estimates of the numbers of bats present. Working in

collaboration with Professor Margrit Betke of BU’s Department of Computer Science, Kunz and Hristov expect to censusthis colony monthly (mid-March through mid-October) for the next three years. Kunz notes that “ultimately we hope thatthe information obtained will help inform managers and the public about the ecological and economic importance of batsthat roost in one of the nation’s premier national parks.”

Previous photographic methods used to estimate numbers of Brazilian free-tailed bats at Carlsbad Caverns haveproduced highly variable and questionable results. Notwithstanding, even with crude estimates, it appears that there hasbeen a general downward trend in numbers of bats since the park was established in the late 1920’s. Some of the observeddeclines in numbers of bats during this period may reflect disturbances from increased numbers of visitors to the cavernand mortality from pesticide contamination of insects in nearby agricultural landscapes. To better understand factors thatmay be causing these declines, according to Kunz, “it is clear that accurate estimates of colony size and assessment oflong-term trends in this bat colony are needed to better inform both resource stewardship and management of CarlsbadCaverns.”

Brazilian free-tailed bats in the night sky,

detected using an infrared thermal camera.

Rabies Project...Continuedtissues of big brown bats throughout its distributional range in North America and Brazilian free-tailed bats in thesouthwestern U.S. Widmaier’s research will focus largely on assessing levels of glucocorticoids (stress hormones) inpopulations of both species captured in natural and human-altered environments and will correlate these findingswith immune responses of rabid versus non-rabid bats. Sorenson’s research will focus on the genetic structure ofthese same populations and will correlate his findings with genetic variation in rabies viruses. Two field techniciansand three graduate students from Boston University will be supported by this project.