Hi all,

Here’s an update on the conditions during the first trip in 2023. The estuary was still extremely salty with surface salinity near the mouth well above 20. An oyster farmer friend measured a salinity of 28 in a creek near Bay River. We did have a little rain associated with a strong Christmas time cold front. The salt wedge still extends upstream of New Bern but higher flows have pushed the salt wedge downstream of Streets Ferry Bridge. The water is seasonably cold, < 10C. Dissolved oxygen conditions were normoxic throughout the estuary. Elevated turbidity (>10 NTU) at the head of the estuary likely resulted from higher flows. A subsurface chlorophyll maximum extended from station 30 to station 120 at ~1.5 m depth. Examination of station 50 surface water revealed numerous Prorocentrum minimum cells. Prorocentrum minimum is a shade adapted species that commonly forms subsurface maxima at low light levels. I bet that the observed subsurface chl-a maximum is the beginning of the nearly annual late winter/early spring bloom of Prorocentrum minimum. P. minimum isn’t known to produce toxins/ kill fish but it has been shown to cause problems with oysters. Fortunately, the area where it tends to bloom is too fresh for oysters anyway. The crew plans to be out again later this week and we’ll see how the bloom’s developed.

Best,

Nathan