The Puget Sound Ecosystem Monitoring Program (PSEMP) has released its 13th annual overview of Puget Sound’s marine water conditions. The report is funded in part by the Puget Sound Institute and is produced by 67 contributors from federal, tribal, state, and local agencies, academia, nonprofits, and private and volunteer groups.
The compilation looks back on the marine conditions from the previous year (2023), and the findings are used to inform the Puget Sound Partnership’s Vital Sign indicators, a measure of the health of the ecosystem. Now, scientists hope to use the combined data from more than a decade’s worth of reports to analyze larger trends. The report summarizes monitoring data ranging from temperature and salinity to dissolved oxygen and plankton abundance. It also includes special sections on trends for forage fish, marine birds and mammals, and pollution.
By all accounts, 2023 saw few extremes, but was “inconsistent” according to Jan Newton of the University of Washington’s Applied Physics Lab. Newton, an oceanographer who wrote the report’s summary pointed to Puget Sound’s phytoplankton counts as an example. “It was kind of an oddball year, because there were species that hadn’t been reported before that were observed, and others that were more typical that were missing or lower in abundance,” she said.
While phytoplankton may not be on the radar of most casual observers, for oceanographers, changes in phytoplankton abundance can have a similar weight to a rare sighting of a shark or an orca. These tiny plantlike creatures make up the base of the food web and can also form large algal blooms under certain conditions that can deplete the water of oxygen, or create toxins that are deadly to humans and wildlife.
Harmful algal blooms and lack of oxygen (hypoxia) weren’t larger concerns than usual in 2023, but scientists found themselves puzzling over the appearance of some phytoplankton species and the disappearance of others.
From the report:
- Trieres mobiliensis, a cosmopolitan diatom species not seen before in our 10-year sampling program but recorded previously for Puget Sound, bloomed from mid-September to mid-October throughout the Central Basin.
- Phytoplankton abundance in Padilla Bay was much lower in 2023 than it has been in recent years. More specifically, blooms of the genera Leptocylindrus, Skeletonema, and Chaetoceros were observed in July and August of 2020 and 2022, but these blooms were not detected in 2023.
- It was an anomalous year for phytoplankton due to the absence of taxa that are typically very abundant.
One of the biggest drivers of these anomalies was likely the year’s variable weather. “It started colder than normal and ended warmer than normal,” Newton said, “but it was also a dry year, so the river flow stayed consistently lower than normal throughout.” That may have benefitted some phytoplankton species while hampering others, although the exact causes may require more study.
Read more about phytoplankton in the Encyclopedia of Puget Sound.
Unless there is an extreme event, like 2014-2016’s marine heatwave (dubbed ‘the Blob”) or an El Niño year, it is sometimes difficult for scientists to identify trends using short-term monitoring data, but now scientists are hoping to look at the accumulation of years of PSEMP’s marine water reports to identify larger patterns. Newton hopes to spearhead the effort with the help of UW student interns next year.
“We’ll be looking for things that stand out, like banner years with particularly high or low phytoplankton,” she said. “And we’ll look at what was going on in water and weather conditions as well as up the food web — can we see any of these processes or any of these connections when we look across time? We want to summarize the reports and look at how things have varied year by year by year.”
The most obvious place Newton expects to see trends is with climate impacts. “That’s huge,” she said. “Things like droughts and marine heat waves are getting more frequent and are really affecting Puget Sound. [By looking at the reports] we won’t just have to say ‘Well, there might be an effect.’ We will have the data.”
Here is a summary of major findings from the report compiled by PSEMP. The report also includes yearly updates on the status and trends forage fish, marine birds and mammals, and pollution.
Major findings (text provided by PSEMP):
In summary, 2023 was a bit of a variable year. The year started with air temperatures cooler than average, then developed to much warmer than average and then remained warmer. Water temperatures largely mimicked this pattern of cool anomalies followed by warm.
In contrast, precipitation and river flow were less than average over most of the year: 2023 had persistent dry conditions (except for December) and lower than average river flow. Both led to higher salinity throughout the year and one of the saltiest years on record. Seawater oxygen concentration fit a variable pattern, with most basins showing weak positive DO anomalies during the first half of the year and negative anomalies in the fall, though no fish kills were observed.
Perhaps variation in these unique conditions led to somewhat of an ‘oddball’ year for plankton. Atypical phytoplankton community composition was observed in many areas, where many of the usual taxa were either absent or atypically low and some species not previously seen were observed. Some harmful algal bloom species decreased while others increased. Zooplankton abundances and biomass were lower and peaked later for many taxa compared to past years, and some community composition changes were observed compared to prior years.
Higher trophic levels had mixed signals, with both successes and failures for herring, some hopeful news for some seabirds, but worrisome records for marine mammals in the San Juan Islands.
A human footprint was clearly evident, with climate change effects, increasing carbon dioxide concentrations, and pervasive and increasing microplastics in Puget Sound sediments. As always, a single year is difficult to decipher, but the continued documentation of annual patterns via this overview will help us to identify emerging conditions.
This edition of the 2023 Puget Sound Marine Waters Overview report once again directly informs the Puget Sound Vital Signs. The majority of technical summaries (32 out of 38) collectively inform many of the Vital Signs nested under the Puget Sound Partnership’s ecosystem recovery goals (Thriving Species and Food Webs, Functioning Habitat, Healthy Water Quality, Healthy Human Populations, and Vibrant Human Quality of Life). In this manner, the annual report makes a valuable contribution to our shared understanding of ecosystem conditions as they relate to Puget Sound recovery effort.
Download the full report on the Encyclopedia of Puget Sound.