Trends in shrimp and crab populations are can serve as indicators of the quality and quantity of suitable habitat, as well as of food availability. Blue crabs, two species of shrimp (brown and white), and oysters are analyzed for the report card. Blue crab populations in Galveston Bay appear to have stabilized, earning a grade of C, and white shrimp maintained a B. Overall, shellfish maintained a C grade. Oyster populations and the reef habitats that they create in Galveston Bay have been negatively impacted by Hurricane Harvey in 2017, the drought of 2011, Hurricane Ike in 2008 and increased fishing pressure, but oyster populations in Galveston Bay received a C for a fourth year, indicating that the population is holding steady.

More than 100 species of finfish can be found in the Galveston Bay ecosystem. Finfish are also the base of a significant recreational fishery. Surveys of finfish indicate that most populations have been consistent since 2008, earning finfish a C. Populations of 10 species analyzed are maintaining Cs, while sand seatrout and bay anchovy improved from a C to a B and spot declined from a B back to a C.

Birds depend on high-quality nesting and feeding habitat to thrive, making them an excellent indicator of the Bay’s health. After near extinction in the 1960s, the brown pelican population in Galveston Bay has rebounded due to a reduction in the use of harmful pesticides such as DDT . Since 2008, most bird populations have been holding steady, earning birds a C. This year, the snowy egret continued to show a moderate decline with a grade of a D. Roseate spoonbill, tri-colored heron, and laughing gull all showed a moderate population decline, going from a C to a D.

Exotic species are species of plants, animals and microorganisms that are transported to the Galveston Bay Watershed from other parts of the world. These exotic species did not evolve here and therefor, lack the predators, parasites and diseases that keep their populations under control in their native ranges. Exotic species are recognized as being invasive when they cause negative ecological, economic, or social impacts in their new home.

Invasive species are harmful to natural systems and some (such as the zebra mussel) are destructive to infrastructure. Invasive species are often very difficult and expensive to control and can damage crops, fisheries, habitats such as coastal prairies, forests, and other natural resources. Invasive plants can choke streams and waterways and cause forest fires to burn hotter while invasive fish can burrow into streambanks, causing water quality issues.

As of 2022, more than 100 species of invasive plants and animals have been found in the Galveston Bay watershed. Reports of new invasive species found in Galveston Bay since 2005 continue to remain low and no invasive species have become established in the Bay, yielding a B grade. The rivers and bayous, however, earned a grade of D as there are multiple invasive species that have become established and are causing problems in our wetland prairies, forests and waterways. Invasive species commonly found in the region include water hyacinth, privet, Chinese tallow, fire ants, feral hogs, armored catfish and zebra mussel—which was reported in Lake Livingston in 2016. The majority (75%) of invasive species found around Galveston Bay are terrestrial plants.