San Bernard National Wildlife Refuge

The National Wildlife Refuge System is a series of lands and waters owned and managed by the U.S. Fish and Wildlife Service. Wildlife conservation is at the heart of the refuge system. It drives everything we do from the purpose a refuge is established, to the recreational activities offered there, to the resource management tools we use.  

Wetland Restoration and Management 

Because of the significant loss of wetlands, one of the refuge’s top priorities is providing freshwater wetlands among the coastal environments. To do this, San Bernard National Wildlife Refuge has constructed shallow wetlands utilizing roads, levees, and water control structures to hold or flush water from the units. Different strategies are implemented according to the time of year and types of birds using the refuge. Although rainfall is the principal source of water, during droughts, the refuge must supplement rainfall using ground water pumped from wells. This option can be expensive but, during severe droughts, San Bernard National Wildlife Refuge may have the only ponded freshwater for miles around. 
 
It is necessary to ensure water levels are maintained to promote food production. This requires the right amount of sunlight and water depth to support abundant and diverse populations of invertebrates and submergent and emergent native plants. Invertebrates, including insects, are an important protein source for waterfowl and shorebirds. Seeds and plant parts (leaves, roots, and tubers) provide energy and essential nutrients for wintering waterfowl. Often, mechanical treatment, burning, and chemical manipulation may be required to promote native vegetation and set-back succession to increase productivity.

Fire Management 

Historically, wildfire was an integral part of the coastal prairie ecosystem. Fires from lightning strikes would sweep across the landscape maintaining the grasslands and keeping trees and brush from becoming established. Today, federal wildland firefighters work closely with refuge biologists to mimic what used to occur naturally through controlled, or prescribed burning. Controlled burns help maintain the coastal and inland prairie, upper saltmarsh and freshwater wetlands by removing dead grasses and woody vegetation. The fire recycles nutrients back into the soil and encourage the growth of native plants that are adapted to fire. Controlled burning removes potentially hazardous ‘fuels’, which left unburned will accumulate and ultimately burn hotter and be much more destructive to the habitat and dangerous for our adjoining communities. 
 
The refuge conducts prescribed burns on a rotational basis, burning approximately every four to five years or more often if the habitat will benefit from increased fire. Fire staff monitors weather and fuel conditions to ensure the burns achieve the best results for the habitat with minimal impact to the refuge’s human neighbors. They work closely with other partners and communities to protect people and property while maintaining the refuge’s healthy and productive ecosystems. The Texas Mid-Coast National Wildlife Refuge Fire Program is dedicated to protecting life, property and natural resources.

Invasive Species Management 

Natural habitats are increasingly invaded by non-native or invasive species invasive species
An invasive species is any plant or animal that has spread or been introduced into a new area where they are, or could, cause harm to the environment, economy, or human, animal, or plant health. Their unwelcome presence can destroy ecosystems and cost millions of dollars.

Learn more about invasive species . The refuge tries to combat this invasion by restoring or mimicking historical processes when possible. If this option isn’t available, we must resort to mechanical or chemical techniques to control these invasive species. 
 
A few of the more problematic invasive plants that the refuge deals within prairie habitats are Chinese tallow trees and deep-rooted sedge. In freshwater wetlands, saltcedar and water hyacinth are some invasive plants.

Invasive animals can also be an issue and displace native species or compete with them for resources. Feral hogs are omnivorous, consuming eggs as well as young wildlife, and can be extremely destructive. Hogs root for acorns, pecans and grubs, which creates disturbed soil beds for invasive plants and further degrades natural habitats.   

The apple snail is an invasive species in inland freshwater lakes where flooding events, like Hurricane Harvey, enabled the snail to move to new areas. The snail reproduces rapidly, and the population can quickly become a management problem. When the snails consume submergent and emergent vegetation, food becomes limited for waterfowl and other waterbirds. To remove the snail, refuge staff and volunteers paddle the lakes, searching for and removing snails and smashing egg masses to limit reproduction. This intense activity has been ongoing at the Hudson Woods Unit since 2019 and has removed more than 50,000 adult snails.