Places We Protect

Clive Runnells Family Mad Island Marsh


Clive Runnells Family Mad Island Marsh Preserve
Mad Island Marsh Clive Runnells Family Mad Island Marsh Preserve © Ian Shive

Clive Runnells Family Mad Island Marsh Preserve is part of an expansive coastal wetlands system.



The coastal prairie, freshwater wetlands and salt marshes that comprise Clive Runnells Family Mad Island Marsh Preserve are in dynamic and continuous flux. The landscape is dotted with slow-draining natural depressions, providing ephemeral wetlands for a rich variety of wildlife species.

Maintaining the delicate balance of this region’s natural function protects a critical ecosystem threatened by development and overuse and enhances its resilience to extreme weather, fragmentation and human degradation. 


Over 75 years ago, an expansive coastal prairie and wetland system stretched nearly unbroken across nine million acres in Texas and Louisiana. After decades of overuse and development, only two percent endures today. This makes Mad Island Marsh Preserve an important piece of a broad network of coastal conservation lands along the Gulf Coast. Its continuum of habitat helps reduce erosion and contributes to the overall health of Matagorda Bay, which meets with the Gulf of Mexico, improving resilience for marine life, endemic plants, wildlife and coastal communities.

Situated at the confluence of two principal North American migratory bird routes, the preserve also provides nesting, feeding, resting and roosting habitat for over 250 species of birds. Notable species include the endangered whooping crane, the rare Le Conte’s sparrow, and over 20 species of waterfowl. For years, the Smithsonian Migratory Bird Center has operated a bird banding station on the preserve to study the patterns and behavior of migratory birds. Additionally, the annual Matagorda County-Mad Island Marsh Christmas Bird Count is one of the most prominent Audubon Christmas bird counts throughout the country, ranking first in number of species tallied for over a decade. Other wildlife species found on the preserve include everything from red drum, blue crabs, brown shrimp, southern flounder and speckled trout to bobcats, rattlesnakes, white-tailed deer and coyotes.  


Establishment of the Clive Runnells Family Mad Island Marsh Preserve dates back to 1989, when Clive Runnells II donated over 3,000 acres of coastal wetlands and upland prairies to the Conservancy. The land is directly adjacent to the Texas Parks and Wildlife Department’s Mad Island Wildlife Management Area, which the Conservancy helped establish with a 5,700-acre donation to the Texas Parks and Wildlife Department. In 1993, the Conservancy added 3,900 acres the preserve with critical support from the North American Wetlands Conservation Council, as well as the National Fish and Wildlife Foundation, Dow Chemical, US Environmental Protection Agency, Trull Foundation and Communities Foundation of Texas.

In the 1980s and 1990s, much of our work at Mad Island centered around enhancing the freshwater wetlands and coastal marshes for wintering waterfowl. In close partnership with organizations like Ducks Unlimited and the U.S. Fish & Wildlife Service, we created over 500 acres of seasonally flooded wetlands that can provide critical stopover and wintering grounds for migrating birds.

Today, we’ve broadened that focus, managing the preserve using prescribed fire, invasive species control, and native seed harvesting and development—with an eye toward supporting this ecosystem’s natural processes to create functioning, connected and resilient communities that support the health of the broader Gulf Coast prairies and marsh ecoregion.


Limited Access

Visitation is by appointment only outside of regularly scheduled events.


Bird and wildlife watching, hiking


7,063 acres

Explore our work in this region


Visitation is open for volunteer workdays and various special events throughout the calendar year. An appointment is needed for visits outside of these organized events. For more information, contact Preserve Manager Steven Goertz ( 

We're also tracking wildlife sightings in and around this area. To log your findings and see what has been recorded nearby, visit iNaturalist or eBird



Community-Based Science

Staff, volunteers and visitors are recording our wildlife sightings in and around Mad Island Preserve. To log your findings and see what has been recorded nearby, join our iNaturalist or eBird communities.