Blue Catfish
Blue catfish
Blue catfish were introduced to Chesapeake Bay tributaries in the 1970's and 1980's. According to Trawl Survey data, blue catfish are currently more abundant in the James, York, and Rappahannock River than either white or channel catfish. Blue catfish have been collected by the Trawl Survey in salinities as high as 21.8 parts per thousand.
Blue catfish
This specimen is the largest blue catfish documented by the survey. It was collected from the Pamunkey River in 2007, weighed 24 kg (52 lbs), and was 100 cm (39 in.) in length.
Blue catfish
Blue catfish feed on a variety of organisms, including fish, bivalves, and small crustaceans. The barbels (or "whiskers", hence the name catfish) around their mouth contain taste buds to assist in finding prey.
- This species first recruits to the survey gear in August.
- The Young-of-Year cutoff values are:
- August: 0-115 mm.
- September: 0-130 mm.
- October: 0-130 mm.
- November: 0-130 mm.
- December: 0-165 mm.
- January: 0-165 mm.
- February: 0-165 mm.
- March: 0-165 mm.
- April: 0-50 mm.
- May: 0-50 mm.
- June: 0-75 mm.
- July: 0-100 mm.
- Index months are in bold.
- In 2018, the recruitment window for juvenile and age 1+ Blue Catfish was changed from the period December to March to the new period between September and November. All of the annual indices for Blue Catfish were recalculated based on the new recruitment window.
- Because Blue Catfish are restricted in their distribution, an index of abundance is calculated for each tributary. All stations in the upper river and a portion of stations in the lower river are used.
- The Age 1+ index for this species contains several year classes. It may be possible to split out individual age groups in the future.
Data collected after the transition to a new vessel and net (June 2015) have been adjusted by a species-specific calibration factor.