Maryland Department of Natural Resources biologists regularly use seine net surveys to monitor aquatic life in the Chesapeake Bay and its tributaries, providing essential data for fisheries management in Southern Maryland and across the state.
During Maryland Science Week in fall 2025, DNR staff joined Huntingtown High School AP environmental science students and Smithsonian Environmental Research Center personnel at the Reed Education Center in Edgewater for a hands-on demonstration of beach seine netting in the Rhode River. Students observed the deployment of a 100-foot-long 4-foot-deep net and learned how land use, particularly impervious surfaces such as roads and parking lots, affects fish habitat. Areas with 10 percent or more impervious surface can reduce water clarity and dissolved oxygen levels, harming aquatic environments.
The demonstration captured local species, including striped bass, blue crab, menhaden, silversides, and a horseshoe crab. Seine nets allow biologists to sample near-shore shallow waters efficiently by encircling fish and bringing them to shore for identification, counting, and measurement.
DNR conducts multiple seine net studies, some funded by the Sport Fish Restoration Fund, which receives support from fishing license, tackle boat, and marine fuel purchases. Licenses are available online through MD Outdoors or at local agents.
The Estuarine Fish Community Sampling Study involves 130 beach seine pulls each summer in shallow Chesapeake Bay tributaries. Biologists separate fish by life stage count them measure select species and record water quality. In 2025 the survey documented 50 species including freshwater types such as largemouth bass chain pickerel and black crappie plus marine species like bluefish black drum and northern puffer. Data help evaluate nursery and adult habitats for recreationally important finfish such as striped bass yellow perch white perch and menhaden.
The Juvenile Striped Bass Survey one of the longest-running fish surveys in the United States began in 1954 and samples 22 consistent sites across Maryland waters of the Chesapeake Bay. Biologists make replicate hauls with 100-foot beach seines three times per summer at each site. The 2025 young-of-year index measured 4.0 an improvement over recent years but below the long-term average of 11. This marks the seventh consecutive year of below-average spawning success for Maryland’s state fish rockfish despite a currently strong adult stock. The survey provides early warnings about future population trends and documents relative abundance of other species.
Maryland DNR has restored American and hickory shad populations since the late 1990s using haul seine surveys in deeper waters of the Choptank and Patuxent rivers among others. These boat-assisted nets help calculate wild abundance larval mortality and stocking success. Efforts have restored hickory shad in the Patuxent and Choptank but limited spawning adults hinder growth elsewhere.
In Maryland’s Coastal Bays behind Assateague Island DNR performs 38 pulls each June and September with a 100-foot 6-foot-deep bag seine. The survey targets nurseries for summer flounder black sea bass weakfish spot croaker menhaden American eels and bluefish while noting submerged aquatic vegetation and invertebrates. Since 1972 it has recorded more than 130 fish species 26 mollusks and 11 macroalgae. Data inform stock assessments federal reports and university studies including incorporation of tautog juvenile indices into Atlantic States Marine Fisheries Commission assessments.
Southern Maryland residents in Calvert St. Mary’s and Charles counties benefit directly from these surveys. Healthy Bay fisheries support recreational angling charter businesses and commercial harvests that contribute to the regional economy. Data guide regulations that sustain species like striped bass important to local anglers near the Patuxent River and Chesapeake waters.
DNR encourages public involvement in conservation through fishing licenses and awareness of land-use impacts on water quality. Continued monitoring helps balance environmental protection with sustainable use of Maryland’s aquatic resources.
The Maryland Department of Natural Resources released details of its seine net programs on March 24 2026 highlighting their role in understanding life below the Bay’s surface.