June 10, 2025 — Blue crabs in the Chesapeake Bay have dropped to a “distressing low” number, experts say, marking several years of repeated declines and raising concern about their long-term health.
The estimated number of crabs was 238 million, the second-lowest point since an annual blue crab dredge survey to measure their population started in the 1990s and coming shortly after 2022’s record low of 226 million crabs, according to experts. The survey found that the decline hit all of the crustaceans, regardless of maturity or gender.
“It’s disturbing because we’ve seen in all sectors — adult males, adult females and juvenile crabs — drops in their numbers,” said Allison Colden, Maryland executive director for the Chesapeake Bay Foundation. The biggest concern, she and other experts said, is the drop in juvenile crabs.
“There’s a disconnect,” she said, “in the productivity of the blue crab population and the number of females in the water.”
The causes of their decline are a bit of a mystery to scientists. The blue crab population can vary widely each year, depending on several factors, including changes to their habitat — especially a loss of underwater grasses that are critical for young crabs, an increase in predators such as blue catfish and red drum fish, pollution runoff into the bay and dramatic shifts in wind, current and storm patterns that can especially affect juvenile crabs.
“If it gets too cold too quickly that causes them to die, and we’ve seen a very high rate of crabs dying over the winter,” Colden said.