About Madrean Discovery Expeditions:

 Madrean Discovery Expeditions, a Signature Program of Greater Good Charities, is dedicated to exploring, studying, and protecting the Madrean Archipelago, a series of unique ecosystems that range from New Mexico and Arizona to Mexico. Throughout the year, groups of uniquely qualified and multinational participants come together to record the plants and animals of this incredible region, focusing on the vastly understudied region of Sonora, Mexico. This information is then stored in an open-source database for the world to share, study, and use to preserve these ecosystems forever. 

Check out our flora and fauna database here: www.madreandiscovery.org

Biodiversity records
International Volunteers
Wildlife Cameras

What are the Sky Islands?

Sky Islands are isolated mountains surrounded by radically different lowland environments. Pine-oak forests sit on each mountaintop in the Madrean Sky Islands, but they are located in and surrounded by the hot and arid deserts of the Sonoran Southwest. That's what makes them so unique.

What is a biodiversity hotspot?

Biodiversity hotspots are the most biologically-rich areas on Earth, but they are also the most threatened areas, because they are home to thousands of unique and endangered species. The Madrean Sky Islands are located in the Madrean Pine-Oak Woodland biodiversity hotspot.

The Madrean Archipelago

The Madrean Sky Islands, also known as the Madrea Archipelago, are a series of 57 isolated mountain ranges that stretch from Arizona and New Mexico to Sonora, Mexico. Each Sky Island contains a plethora of miniature ecosystems, making them some of the most biologically rich and diverse regions around the world. These hot spots are home to more than a hundred mammals ranging from elusive jaguars and ocelots to endangered bats, turtles, butterflies, lizards, and more.

Unfortunately, the ecosystems located in Mexico are vastly understudied, endangering the land and species that exist there.


The Expeditions

The first step in conservation is the observing, studying and recording of a region’s flora and fauna. Without this critical piece, a region’s plants and animals cannot be accurately protected.

Twice a year, a multinational group of scientists, land managers, students, and photographers embark on a multi-day expedition to one of the understudied Sky Island mountain ranges in Sonora. MDE’s scientific team also conducts one mini-expedition to an additional Sky Island each year. Each day, the group observes and records the findings within the natural habitat. So far, a total of 20 Sky Island sites have been observed and recorded by the MDE team, but our ultimate goal is to visit and document all 57 islands.

The Database

The findings from our expeditions are stored in a public database and used to identify new species, advocate for land conservation, and establish new protected areas. We make this information completely free to the public so we can spread awareness for these unique species. The database contains a total of over 34,000 records and has been used as a reference in scientific publications 59 times.

Wildlife Cameras

The MDE Wildlife program records secretive and nocturnal mammals in high priority areas using wildlife cameras. We currently have 45 active MDE Wildlife camera studies underway in 7 mountain ranges, 5 ranches, and the Mesa Tres Ríos. These studies have also provided records to the MDE database, including 3 new localities for the jaguar and 15 for ocelots. These cameras are crucial for studying the Sky Islands.

Where We’ve Been

Map of Madrean Discovery Expeditions Locations

Meet Our Director, Dr. Tom Van Devender

Thomas R. Van Devender (pictured right) was the Senior Research Scientist at the Arizona-Sonora Desert Museum for 25 years, where he conducted research on a broad range of natural history topics. He has published well over a hundred publications on a range of topics, including natural history, paleoecology, desert grasslands, desert tortoise ecology, local floras, ethnobotany, herpetofaunas and the Madrean Archipelago.

In May 2015, Tom began as the Director of Biodiversity Programs at Greater Good Charities, where he organizes biodiversity inventories to Sonoran Sky Islands in the Madrean Discovery Expeditions (MDE) program, which documents the diversity of animals and plants in the 35 isolated Sky Island ranges and complexes in Sonora, Mexico, and manages Project Wildcat, our predator projection program. From 2009 to 2014, Tom was the Manager of the Madrean Archipelago Biodiversity Assessment (MABA) project at Sky Island Alliance. At MABA and MDE, Tom has organized ten binational expeditions with large volunteer groups of taxonomic specialists, land managers, college professors and students, local residents, photographers, and journalists to make new observations in high-diversity areas in Sky Island ranges in Sonora.

Donate Today

Since 2009, we've gone on 20 expeditions. With your help, we can continue this tradition and ensure that our Sky Island ecosystems remain a global biodiversity hotspot. Every dollar raised will go directly toward funding the expeditions.

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