2023-24 Winter Seasonal Summary Has Good News for Blue Crabs, Striped Bass

Submitted by Kim on 04/23/2024

The NOAA Chesapeake Bay Office’s Winter 2023-24 Seasonal Summary holds good news for blue crabsstriped bass, and—unfortunately—invasive blue catfish

 

Each of the seasonal summaries includes analysis of observations from CBIBS buoys, satellites, and other data sources to determine how Bay conditions compared with the average over the past 20 years. Scientists also discuss how those differences may have affected species that live in the Chesapeake Bay.

Water Temperature

Overall, water temperatures in the Chesapeake Bay were warmer than average. There was a period in late January where temperatures dipped below average, but then the waters warmed back up to above average again. 

 

The warmer water temperatures could have reduced the number of blue crabs that died due to cold water this winter. Warmer water temperatures can also lead to plankton blooms in early spring. That would be earlier than usual. 

Map of Chesapeake Bay showing warmer-than-average water temperatures for winter 2023-24

Satellite data show that waters all around the Chesapeake Bay were warmer than average during winter 2023–24. 

Precipitation and Freshwater Flow

The winter was wetter than average for much of the Chesapeake Bay watershed. In fact, southern Maryland saw the most precipitation since 2007, and Tidewater Virginia had the third most precipitation since 2007. That meant that there was also more freshwater flow into the Chesapeake. 

 

This can increase the amount of habitat available for striped bass looking to spawn in the spring. That’s because more flow means more water—and that is more habitat. 

Graph showing December through February precipitation from 2007 through 2024.

Precipitation in southern Maryland for this winter was the highest it has been for any winter since 2007. 

Salinity

Thanks to the higher-than-average precipitation and freshwater flow into the Bay, for much of the winter, salinity in the Chesapeake Bay was lower than average. Invasive blue catfish can live in waters where the salinity is 14 ppt or below. The lower-than-average salinity may have allowed blue catfish to move into new areas. 

Graph showing that salinity at the Potomac CBIBS buoy was lower than average for much of winter 2023-24

While salinity at the Potomac CBIBS buoy is usually above what blue catfish prefer over the winter, this winter, much of the winter was spent with salinities in the range they like to live in. 

See More!

For a deeper dive into winter 2023-24 data, more graphs, and discussion on how conditions may have affected living resources, see the full Winter 2023-24 Seasonal Summary.