Blue Crabs

Blue crabs are vital to our region's economy and culture and an important part of the Chesapeake Bay ecosystem.

Line graph illustrating the total blue crab population in the Chesapeake Bay from 1990 to 2019.

Blue Crabs

For most of the last two decades, the total number of blue crabs in the Chesapeake Bay has lingered below the long-term average. Because blue crabs are so important to the region's ecosystem and economy, both Maryland and Virginia monitor the blue crab population through an annual Winter Dredge Survey. The crabs that are collected at each of the survey's 1,500 sampling sites are measured, weighed, sexed and aged, and the data is used to estimate the number of young crabs entering the population, the number of female crabs old enough to spawn and the total number of harvestable crabs in the Bay.

282 million

The total number of blue crabs in the Chesapeake Bay

According to data from the Winter Dredge Survey, an estimated 282 million blue crabs lived in the Bay in 2021. This is a 30% decrease from 405 million crabs in 2020. 

In the Chesapeake Bay Watershed Agreement, the Chesapeake Bay Program set a population target and an overfishing threshold for adult female blue crabs. In 2021, an estimated 158 million adult female blue crabs lived in the Bay, compared with 141 million in 2020. This number is above the 72.5 million threshold which is considered to be the minimum sustainable level for female blue crabs in the Bay, but lower than the target of 196 million. Blue crab abundance in the Chesapeake Bay is expected to fluctuate annually due to their biology and environmental factors such as temperature, coastal currents, weather patterns, and predation.

Blue crabs are also vulnerable to pollution, habitat loss and harvest pressure. Water quality improvements, underwater grass restoration and proper harvest management will be critical to maintaining this valuable resource.