Protect Mega-Populations

Millions of straw-colored fruit bats (Eidolon helvum) emerge from their tree roosts
located in Kasanka National Park, Zambia.

The importance of bats to their ecosystems is difficult to overstate. This is particularly true where bat populations number in the many millions, as with Mexican free-tailed bats in the Texas Hill Country and straw-colored fruit bat colonies in Africa.

The ecosystem services provided by these mega-populations are profound and, if lost, would have serious consequences for agriculture, forestry, and ecosystem health.

Such populations also hold significant potential for educating the public.

Bat Conservation International will identify and protect mega-populations of bats wherever they are found, including areas containing a high percentage of the total population of individual bat species (major hibernacula, roosting colonies, migratory concentrations, etc.).

Bracken Cave (United States)

BCI owns and manages the property surrounding the largest bat colony in the world, Bracken Cave, located just north of San Antonio, Texas. With between ten and twenty million bats, this colony of Mexican free-tailed bats (Tadarida brasiliensis), along with numerous other large colonies located in central Texas provides area farms with insect pest control services valued at close to one million dollars each year. Learn more about Bracken Cave.

Congress Avenue Bridge (United States)

Also located in the Texas Hill Country, the well-known population of 1.5 million Mexican free-tailed bats that lives seasonally under the Congress Avenue Bridge in downtown Austin is currently well protected. However, this was not always the case. Soon after beginning habitation of the concrete expansion joints on the underside of the bridge in the early 1980s, it appeared the bats might be forcibly evicted.

Through no small effort, BCI’s founder, Dr. Merlin Tuttle, and others led an education and advocacy campaign that succeeded in allowing the bats to remain. Today, they are an important fixture in the city, and the tourism revenue estimated to be generated by visitors coming to watch the nightly bat emergence is in the millions of dollars annually. Learn more about the Congress Avenue Bridge bats.

Kasanka National Park (Zambia)

Straw-colored fruit bat in hand

Every year, the bats arrive during October and November to feed on figs and scatter their seeds, prompting reforestation and ecosystem renewal.

Then, just as suddenly as they arrived, the bats scatter to their other seasonal homes, which are thought to be largely in the neighboring Democratic Republic of the Congo. Surprisingly given the size of this mega-population, we still have much to learn about its ecology and conservation needs.

There is also a great need to educate local hunters and landowners about the value of protecting the Kasanka population. For these reasons, BCI partners with the Kasanka Trust to promote educational activities for local schoolchildren and to hire forest guards. Another recent conservation initiative for the bats of Kasanka is being led and funded by the Max Planck Institute of Ornithology, in which researchers have attached radio transmitters to some of the bats to track their nightly movements and discover their foraging habits.

Escaba Dam (Argentina)

Escaba Dam sign

Large populations of Mexican free-tailed bats are also known throughout Latin America.

The Escaba Dam in Argentina is thought to house South America’s largest bat population with just over 1 million individuals .

BCI and the Program for Bat Conservation in Argentina (PCMA) are partners in studying the ecosystem services of this colony and advocating for its permanent protection.

Monfort Bat Cave (Philippines)

In Asia, BCI has been a long-term partner in protecting the Monfort Bat Cave and its 1.8 million Geoffroy’s rousette fruit bats on the island of Samal in the Philippines. Despite the fact that bats enjoy wide-ranging legal protections in the Philippines, cave roosts are frequently disturbed or even destroyed by irresponsible use by humans.

Such is the case in the region surrounding Monfort Bat Cave, such that the majority of the region’s caves are empty of bats, meanwhile, the Monfort site is literally overflowing with bats. This shows the power of protecting vital roosting habitat, and it was this promise that led BCI to partner with landowner, Norma Monfort, when she appealed for our help in 2006.

Once on the verge of being seized by the government for agricultural development, today the cave is visited by thousands of eco-tourists annually and stands as a bright beacon for the importance and potential for bat conservation throughout Asia.

Preserve Bat Hot Spots

Bat Conservation International recognizes both the immense conservation value and the inherent vulnerability of areas where extraordinary numbers of distinct bat species are present.

These areas present great value and are deserving of conservation due to their uniqueness and their habitat’s ability to support vast numbers of species with differing ecological processes, along with the efficiency of being able to protect so many species in a single effort.

It is also important to avoid tragedies of the commons, by overlooking species or areas because of their apparent abundance. This is especially important in the case of bats because small areas of abundance, with high numbers of species or large populations can also be extremely vulnerable to catastrophic events or the emergence of new threats due to the compact, colonial-roosting nature of many species.

To preserve these vital “bat hot spots,” BCI will seek out opportunities to leverage its conservation impact by identifying and protecting landscapes of high ecological integrity with high bat species diversity.

Global bat species richness map

BCI's progress toward this initiative will depend heavily on availability of and access to existing data and the advancement of new technologies to locate bats and determine species identifications. Sixty million years of evolution have produced more than 1,300 bat species, and although approximate ranges are known for most species, exact roosting locations, migration and hibernation behaviors, and foraging patterns are not well understood, thus making it extremely challenging to document accurate species distributions.

Furthermore, as a gauge to the urgent need for additional bat research and conservation efforts, the IUCN lists 203 bat species as “data deficient,” meaning there is simply too little information known about these species to even label their conservation status, much less pinpoint their locations in relation to other species. Further, there are also at least another 150 bat species newly described and do not even have a species account on the IUCN Red List.

Launch a Global Bat Database

Prioritizing conservation action among 1300+ bat species requires the best possible scientific information. Unfortunately, there are many gaps in the current state of knowledge for many bat species and their habitats, which greatly constrains informed decision making.

Furthermore, the body of bat knowledge that does exist is all too often scattered across the globe, held in various individual and institutional databases, and in many cases, may still reside on the original paper datasheets or on the field laptops of the individuals that collected the data.

These and other challenges make it difficult and even impossible to access the critical data for comprehensive analyses to inform priority conservation programs and research projects. For this reason, Bat Conservation International and Washington DC-based NatureServe are partnering to establish a permanent global inventory for bats that will be accessible for all users via the Internet. Once launched, the Global Bat Conservation Data Center, will provide an invaluable resource to inform bat conservation at a global scale and by all stakeholders.

This long-term initiative will allow objective, science-based conservation and land-use decision making worldwide with bats in mind. We will work with individual researchers, museum collections, research institutions, scientific networks, and government agencies to link their disparate efforts and maximize the availability and value of their data collections by connecting them into the world’s only comprehensive database focused on advancing bat conservation.

The Global Bat Conservation Data Center, currently under development, is also meant to unite the world’s leading researchers and bat conservationists around common understandings of taxonomy, the status of populations and species, and the most urgent conservation needs. Our web-accessible data management system will expand access to and application of essential information about all bats around the world. Meanwhile, we will continue to collate information and catalyze new data collection on priorities and gaps.

Ultimately, the combined data will be used to create biodiversity indicators of bat population health for input into proposed biodiversity dashboards that assesses status and trends of biodiversity across broad landscapes as well as at local scales, effectively translating biodiversity data into relevant, accessible information for broad audiences and policymakers.

Bats represent greater than 20% of the world’s mammal diversity. Their economic and ecological importance, combined with serious population declines, justify the urgent need for comprehensive data to inform proactive conservation. Currently, 17.6% of the planet’s bat species are classified as Data Deficient by the IUCN Red List, meaning that the global scientific community lacks enough basic information to assess the health and status of more than 200 species of bats.

Wide knowledge gaps remain, and a wider chasm exists between the collection of this knowledge and its availability to the decision makers whose policies will help determine the fate of critical habitats and limited natural resources. Our initiative will establish an enduring framework to resolve this dangerous disconnect between the value of bats and regard for their management and conservation. Decisions for ecotourism operations, wind farm placement, choice of agricultural pesticides, the design of protected areas, and other issues should consider the impact on bats.

A global bat database will help overcome this as it unifies, digitizes, and improves the accuracy of large existing datasets while creating a methodological and technical infrastructure for globally consistent collection of new bat data and for implementation of urgent conservation actions.

The Threats that Bats Face on a Global Scale

Bats, like so many other species, face wide-ranging threats around the world: foremost is habitat degradation and loss from a variety of human activities. Other threats include indiscriminant killing based on superstitions or fears of disease; uncontrolled hunting of bats for food and folk medicine; wind turbine-caused mortality; and improper mining of bat guano for fertilizer. Invasive non-native species also pose severe threats.

It is widely believed that as many as 25 of the 47 U.S. and Canadian bat species may be vulnerable to the introduced fungus Pseudogymnoascus destructans, the cause of White-nose Syndrome. By some estimates, WNS has killed more than 6 million bats since 2006 in central and eastern North America.

Hibernating bats in other regions of the world also could be vulnerable. Bats living on islands, by virtue of their isolated evolution and limited geographic range, are particularly vulnerable to introduced species such as the Brown Tree Snake (Boiga irregularis), Yellow Crazy Ants (Anoplolepis gracilipes) or the feral pigs (Sus scrofa) and goats (Capra hircus) that degrade forest habitats.

Without concerted global action, bat populations will continue to fall, driving many species to extinction. BCI is expanding its work around the world, through collaboration with a wide variety of partners, to detect and respond rapidly to critical, often broad-scale threats to bats.  Where necessary, we will invest in research to understand and develop new technologies or methodologies that alleviate serious threats to bats or substantially improve study or public appreciation of bats.


Africa is home to more than 21% of the world’s species of bats (269+ species). Learn more about BCI's collaborative work to address the most serious threats facing Africa’s bats.


Asia is home to more than 34% of the world’s species of bats (448+ species). Learn more about BCI's collaborative work to address the most serious threats facing Asia’s bats.


Europe is home to more than 3% of the world’s species of bats (42+ species).


Oceania is home to more than 13% of the world’s species of bats (176+ species).Learn more about BCI's collaborative work to address the most serious threats facing Oceania’s bats.

Latin America

Latin America is home to more than 26% of the world’s species of bats (345+ species).Learn more about BCI's collaborative work to address the most serious threats facing Latin America’s bats.


USA-Canada is home to more than 3% of the world’s species of bats (47 species). Learn more about BCI's collaborative work to address the most serious threats facing USA-Canada’s bats.


Prevent Extinctions

Photo courtesy of John Woinarski


What is this sound?

Courtesy of Zoos Victoria

Answer: Extinction - A wakeup call for the world!

August 26, 2009: This is the last recorded call of the Christmas Island pipistrelle (Pipistrellus murrayi).

The Christmas Island pipistrelle went extinct despite having a recovery plan, being listed Critically Endangered, and having a valiant recovery effort that included a moderate amount of research and knowledge of the species, a substantial reserve system, and some management of the threats to the species.

Maclaud’s horseshoe bat
The Maclaud's horseshoe bat (Rhinolophus maclaudi) is one of three bat species
listed as either Endangered or Critically Endangered in the western African
country of Guinea.
© Natalie Weber

It is time for Bat Conservation International and all individuals, private and governmental organizations, corporations, and all interested parties to proactively take action for the conservation of the most endangered bats in the world. It is time for all of us to stand together and say through our words and deeds, “Not on our watch!” For many of these endangered bats it is not too late if we take action now!

"Monitoring is a critical part of effective species conservation, but many species are being monitored until they go extinct" Lindenmayer et al., Frontiers in Ecology, 2013.

There are currently 77 Endangered and Critically Endangered bats on the IUCN Red List of Threatened Species, and we anticipate this number to increase as a new assessment is currently underway and as we have come to have a better understanding of the threats facing many of the world's bats. As part of BCI’s new 5-Year Strategic Plan, BCI is committed to preventing extinctions and working collaboratively to help stabilize the declining populations of the world’s most endangered bats. BCI has undergone a priority setting process and has selected an initial 35 priority species on which we will focus our time and resources.

Student Research Scholarship recipient Emma Gomez-Ruiz
BCI partner and Student Research Scholarship recipient Emma Gomez
-Ruiz removes a Mexican long-nosed bat (Leptonycteris nivalis) from a mist
net in northern Mexico while identifying priority roost sites for this
endangered species.
© Eder Hernandez--Ruiz

To advance bat conservation for the world’s most endangered bats, we plan to work collaboratively to launch Rapid Field Assessments  where teams comprised of trained experts, including local leadership, undertake targeted inventories to secure the last known roost sites and, hopefully, identify previously unknown populations.

As part of this strategy, BCI will invest in local capacity and leadership, even as we learn from our local colleagues how to advance bat conservation in some of the most remote regions of the world!

Ultimately, BCI is committed to working together to achieve lasting conservation at scale. To that end, BCI will be working with stakeholders to develop and implement viable Conservation Plans based on the best information available. These conservation plans will chart a path for success and inform actions of BCI and our coalition of trusted partners for endangered bats.

BCI remains committed to the endangered bats that did not make our initial set of 35 priority species. We will work in collaboration with our trusted colleagues and expand our network of existing partners around the world to remain aware and responsive to changing circumstances.

As new information is acquired, a new crisis develops that exacerbates the situation facing bats not on our priority list, or there is a new opportunity that arises to have lasting conservation impact, BCI will be able to take action, adjust our priorities, and work together to make a difference.

Livingstone’s flying fox
Although Livingstone's flying fox (Pteropus livingstonii) is not one of BCI's current priority species, its endangered status
means that BCI continues to monitor ongoing conservation efforts and needs through local partners in Comoros.


BCI’s Granting Programs may be a source of potential funding in support of endangered bat conservation. For promising projects focused on the conservation of endangered bats, BCI may be able to provide letters of support to endorse the project with other organizations or even in support of funding proposals. Please contact BCI if you are interested in exploring these options.

Number of Endangered & Critically Endangered Species by Country
(IUCN Red List of Threatened Species)



BCI’s work to prevent extinctions in Africa is currently focused on 6 of the 11 Endangered and Critically Endangered bats currently identified by the IUCN Red List.


BCI’s work to prevent extinctions in Asia is currently focused on 2 of the 25 Endangered and Critically Endangered bats currently identified by the IUCN Red List.


BCI is not currently working on extinction prevention for Europe's 3 Endangered bats. BCI does, however, collaborate with several leading bat conservation groups in Europe, along with providing funding for Student Research Scholarships and Global Grassroots Grants focused in this region.

Latin America

BCI’s work to prevent extinctions in Latin America is currently focused on 9 of the 15 Endangered and Critically Endangered bats currently identified by the IUCN Red List.


BCI’s work to prevent extinctions in Oceania is currently focused on 16 of the 22 Endangered and Critically Endangered bats currently identified by the IUCN Red List.

United States-Canada

BCI’s work to prevent extinctions in the United States & Canada is focused on the three 3 Endangered and Critically Endangered species currently identified by the IUCN Red List, the additional 5 species and sub-species that are identified as Endangered under the US Endangered Species Act, and several other bat species whose status is particularly imperiled due to serious threats like White-nose Syndrome, wind energy facilities, climate change, habitat fragmentation, and human disturbance.


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