September 2024

With data collection complete, we are beginning to strategize some water quality data analysis. One thing we must consider early on is if our sampling years (2023 and 2024) were "typical" water quality years for the estuary. We need that information so that we provide the proper context to all our findings. The System-Wide Monitoring Program (SWMP) has collected continuous water quality data in 4 locations since 2013 which allows us to compare our project sampling years to the 11 year record. Below is an example that shows conductivity at the Oliver Bridge station. Notice that the 2023 average daily conductivity values at Oliver Bridge were near the upper range of the historic daily range for the entirety of the summer. These abnormally high values reflect drought conditions in the watershed. It finally rained a few inches in late September 2023 resulting in the dramatic dip in conductivity. We are excited to tease apart how the 2023 drought impacted water quality that then may have influenced phytoplankton community dynamics and bloom formation. 

July 2024

This is a Dolichospermum crassum colony from North Bay in July 2023. Note the specialized nitrogen-fixing heterocyst cells (large, round, and surrounded by clear sheaths) that are present on the colony.  Phytoplankton samples processed so far from North Bay have contained a very diverse array of cyanobacteria and other algae. 

May 2024

Peter presented some preliminary data analysis at the St. Louis River Summit in March. Take a look at his presentation slides below. Based on some preliminary site redundancy analysis, we can already see there is likley water quality overlap among several of our middle and upper estuary sites. 

December  2023

Measures of the pigment chlorophyll-a can tell us a lot about the differences in algal abundance among the 8 sampling sites. We will have more comprehensive understanding of the phytoplankton community differences later, but right now we can already see some vast differences in algal abundance. Check out the graph below and you may notice that only two sites have high winter values (Barker's Island and Allouez Bay) and our lower estuary sites have much higher peaks August - October than our upper and middle estuary sites.  There is even more to unpack from these values which we will share at the St. Louis River Summit in March 2024. 

AL = Allouez Bay, BA = Barker's Island, BI = Billing's Park, KI = Kingsbury Bay, MI = Miller Creek/WLSSD, MU = Mud Lake, NO = North Bay, PO = Pokegama Bay. 

August 2023

Our Barker's Island sampling site has a water quality sonde that is logging data every 15 minutes. It is a great tool for observing how variable some water quality parameters are over the course of a day. Take a look at how much dissolved oxygen fluctuates over the course of several days at Barker's Island below. These tell-tale daily swings in dissolved oxygen indicate a high amount of photosynthetic organisms in the water.  Oxygen is being produced in abundance when the sun is out during the day, and then oxygen is being taken up at night for respiration.  High values of dissolved oxygen and pH are one sign that an algal bloom could be happening. That is why we are keeping our eye on the live data from Barker's Island. Take a look at live data at this link. 

May 2023

We are just beginning to characterize the 8 sampling sites. The violin plots below display mean values and distributions of selected parameters at all sites from the first four sampling events (October through March).  Site code key: AL = Allouez Bay, BA = Barker's Island, BI = Billings Park, KI = Kingsbury Bay, MI = Miller Creek, MU = Mud Lake, NO = North Bay, & PO = Pokegama Bay.

We are also in the very early stages of examining phytoplankton samples, with more extensive enumeration taking place after Peter's intensive identification training in June. However, a reproduction event by Aulacoseira, a common centric diatom genus, was observed in an Allouez Bay sample from 2/27/23. In the photomicrographs of the event below, the strands are colonies of glass-walled individual organisms. The round structures at the ends of some are called auxospores, zygotes formed after multiple generations of asexual reproduction that will eventually be released and form new colonies.