Newportal Blog
A gateway to oceanographic adventures from the Newport Line and beyond
We are a group of NOAA Fisheries and
Oregon State University scientists that sample the Newport Line fortnightly to understand changing ocean conditions.
Follow us as we share the fun things we learn about this region and other areas of the North Pacific Ocean.
We've been sampling a grid of stations each June since 1998. These stations span from Newport, Oregon, to the northern tip of Washington State and extend from 1 to 30 miles offshore. Although each June is unique in some aspects, June of 2017 was the strangest we've yet encountered in many ways.
Map of the regions sampled with the FV Frosti June 1998 - 2017. Photos courtesy of Scott Melville of Pacific Drone, who was also an FV Frosti crew member.
The first thing we noticed was the pyrosomes that were in high abundance, everywhere. Pyrosoma atlanticum are colonial pelagic tunicates, and reports were coming in of high numbers of them in areas mostly further south of where we sample. But we were catching them for the first time off of northern Washington!
Pyrosomes were found throughout the sampling grid, sometimes in very high numbers.
Moreover, catches of many of our fish species were quite different than an average year (some more abundant, some less so). The juvenile salmon that are the focus of this study were very scarce - one of the lowest in the 20 years of the time series.
June 1998 - 2017 catches of yearling Chinook and coho salmon. 2017 was one of the lowest catch years in the time-series!
Catches of Pacific pompano (left) and jack mackerel (right).However, warm water species, such as Pacific pompano and jack mackerel (a potential predator on juvenile salmon) were found in high numbers. All of these things point to a much altered ecosystem in this region, and do not bode well for salmon returns.
Due to the unusual nature of these findings, we engaged in multiple outreach efforts to get the word out. More info on these findings can be found at the Associated Press and the NW Fisheries Science Center website.
Tagged: BPA
Large diatom blooms were common all summer and into early September at our long term continental shelf station NH-5 (five miles offshore of Newport). However, towards the end of September, a shift in the phytoplankton community occurred, changing from a diatom dominated community to one with more dinoflagellates. The largest change then was an increase of dinoflagellate species diversity and a decrease in diatom diversity.
Figure 1. Pseudo-nitzschia species (4-5 cell chain) in the net tow sample from NH-5.
On a sunny morning on October 4th, we conducted a short cruise to NH-5. The clarity of the water from the boat and a clean zooplankton net after being hauled through the water indicated the disappearance of a phytoplankton bloom. Upon further analysis under the microscope, we actually saw a mixed composition of diatoms and dinoflagellates in the sample. A few species of diatoms, Cylindrotheca closterium, Proboscia alata and Leptocylindrus danicus, were relatively abundant compared to other diatom species. Also, smaller dinoflagellates were abundant and the diversity of larger dinoflagellates, such as Dinophysis and Protoperidinium, was relatively high.
Harmful algae
Pseudo-nitzschia, the diatom that produces domoic acid, has been persistently present throughout the summer, however they were rare in this recent sample (Figure 1).
Figure 2. Relatively abundant Alexandrium catenella (6 cell chain on the right side).
In contrast, harmful dinoflagellates were present in the net tow sample. Alexandrium catanella (Figure 2) is known to produce saxitoxins which can contaminate bivalves (e.g. mussels) and possibly lead to paralytic shellfish poisoning at low cell concentrations. We also observed the dinoflagellate species Dinophysis acuminata, D. fortii (Figure 3), D. rotundata and D. parva that occur offshore Newport. Some of these species produce okadaic acid and dinophysistoxins, which cause diarrhetic shellfish poisoning. Concentrations of Dinophysis species were low on Oct 4, but it will be important to monitor whether these concentrations increase.
Figure 3. A single Dinophysis fortii cell.
Shifts in the physical conditions
These observed transitions of phytoplankton species composition and abundance, and harmful algae closely followed changes of the coastal wind direction, magnitude and persistence. North/northwest winds (upwelling favorable) significantly weakened after early September while southerly winds (downwelling favorable) occurred two to three times for 5 to 6 days in the last month. Phytoplankton species have in turn responded to these seasonal changes of the coastal winds and the underlying physical processes.
See more blog entries:
May 2017April 2017
March 2017
February 2017
January 2017
August 2016
July 2016
June 2016
May 2016
April 2016
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February 2016
January 2016
December 2015
October 2015
August 2015
July 2015