Tag Archives: plankton

Nitrogen and plankton: Do they hold the missing keys to the food web?

In a way, some of Puget Sound’s most serious ecological problems have been hiding in plain sight. I have been learning a lot lately about plankton, an incredibly diverse collection of microscopic organisms that drift through the water, forming the base of the food web.

Sources of nitrogen in Puget Sound (click to enlarge)
Graphic: Washington Department of Ecology

To put it simply, the right kinds of plankton help to create a healthy population of little fish that feed bigger fish that feed birds and marine mammals, including the endangered Southern Resident killer whales. On the other hand, the wrong kinds of plankton can disrupt the food web, stunt the growth of larger creatures and sometimes poison marine animals.

OK, that’s a bit of an oversimplification, but Puget Sound researchers are just beginning to understand the profound importance of a healthy planktonic community to support a large part of the food web. That’s one of the main points that I try to bring out in five stories published today in the Encyclopedia of Puget Sound. I am grateful to the many researchers who have shared their knowledge with me.

Average daily nitrogen coming in from rivers and wastewater treatment plants (1 kg = 2.2 pounds)
Graphic: Washington Department of Ecology

These stories tie together several major issues all related to nutrients — mainly nitrogen — that feed the marine phytoplankton, which use their chlorophyll to take energy from the sun as they grow and multiply. In the spring and summer, too much nitrogen can mean too much plankton growth. In turn, excess plankton can lead to low-oxygen conditions, ocean acidification and other significant problems.

The complex interplay of planktonic species with larger life forms in Puget Sound is still somewhat of a mystery to researchers trying to understand the food web. As part of the effort, the Washington Department of Ecology is working on a computer model to show how excess nitrogen can trigger low-oxygen conditions in the most vulnerable parts of the Salish Sea, such as southern Hood Canal and South Puget Sound.

Areas of Puget Sound listed as “impaired” for dissolved oxygen (click to enlarge)
Graphic: Washington Department of Ecology

Stormwater is often cited as the most serious problem facing Puget Sound, and we generally think of bacteria and toxic chemicals flowing into the waterway and causing all sorts of problems for the ecosystem. But stormwater also brings in nitrogen derived from fertilizers, animal wastes and atmospheric deposits from burning fossil fuels. Stormwater flows also pick up natural sources of nitrogen from plants and animals that end up in streams.

Sewage treatment plants are another major source of human nitrogen. Except for a few exceptions, not much has been done to reduce the release of nutrients from sewage-treatment plants, which provide not only nitrogen but also micronutrients such as vitamins and minerals. Some experts suspect that nutrients other than nitrogen help to determine which types of plankton will dominate at any given time.

I plan to follow and report on new scientific developments coming out of studies focused on the base of the food web. Meanwhile, I hope you will take time to read this package of related stories:

Automated monitor provides early warning of harmful algae blooms

Automated equipment installed Monday off the Washington Coast will track concentrations of six species of plankton that could become harmful to humans and marine species.

The Environmental Sample Processor, or ESP, collects discrete samples of water and processes them for analysis. Imbedded modules can test for DNA and antibodies to identify the organisms picked up in the seawater. Concentrations of the plankton and their toxins are sent to shore-based researchers via satellite.

The equipment was installed by scientists with the National Oceanic and Atmospheric Administration and the University of Washington. The device was developed at the Monterey Bay Aquarium Research Institute. Stephanie Moore of NOAA’s Northwest Fisheries Science Center explains the benefits of the device in the first video on this page. The second video provides a few more technical details with graphic depictions of the device.

The ESP was deployed in the Juan de Fuca eddy, a known pathway for toxic algae 13 miles off the Washington Coast near LaPush. The remote, self-operating laboratory will operate about 50 feet underwater.

One of the primary targets of the monitoring is Pseudo-nitzschia, a harmful algae capable of producing domoic acid. This toxin can accumulate in shellfish and can cause diarrhetic shellfish poisoning, which can progress to severe illness. Last year, a massive bloom of this toxic algae canceled scheduled razor clam seasons on Washington beaches with untold economic consequences.

The harmful algal bloom (HAB) affected the entire West Coast, from California to Alaska. It was the largest and longest-lasting bloom in at least 15 years, according to NOAA’s National Ocean Service.

“Concentrations of domoic acid in seawater, some forage fish and crab samples were among the highest ever reported in this region,” says a factsheet from the service. “By mid-May, domoic acid concentrations in Monterey Bay, California, were 10 to 30 times the level that would be considered high for a normal Pseudo-nitzschia bloom.”

“Other HAB toxins were also detected on the West Coast. Shellfish closures in Puget Sound protected consumers from paralytic shellfish poisoning and diarrhetic shellfish poisoning.”

Paralytic shellfish poisoning is associated with a group of plankton called Alexandrium, typically Alexandrium catenella in the Puget Sound region.

In addition to sampling for Alexandrium and four species of Pseudo-nitzchia, the ESP is monitoring for Heterosigma akashiwo, which is associated with massive fish kills, including farmed salmon.

Anyone can track some of the data generated by the equipment by visiting NANOOS — the Northwest Association of Networked Ocean Observing Systems.

Early warning of toxic algal blooms can assist state and local health officials in their surveillance of toxic shellfish.

“Anyone can access the data in near-real-time,” UW oceanographer and NANOOS Director Jan Newton told Hannah Hickey of UW News and Information. “It’s an early warning sentry.”

Water quality is defined by its effect on sea life

We just completed another group of stories in the ongoing series we’re calling “Taking the Pulse of Puget Sound.” This latest story package is about marine water quality and marine sediments. (The stories themselves require a subscription.)

Noctiluca, a type of plankton that could disrupt the food web, has grown more prevalent in recent years. Photo by Christopher Krembs, Eyes Over Puget Sound
Noctiluca, a type of plankton that could disrupt the food web, has grown more prevalent in recent years.
Photo by Christopher Krembs, Eyes Over Puget Sound

For all my years of environmental reporting, I have to say that I’ve never really understood the meaning of water quality. Keeping the water free of chemicals and fecal bacteria is one thing. Safe levels of oxygen, temperature, acidity and suspended sediment are other important factors.

But in the real world, you never find ideal conditions. You take what you get: physical conditions dictated by weather, climate and bathymetry; a strange brew of toxic chemicals; and a mix of nutrients and organic material, all drifting through complex cycles of life and death.

Water quality means nothing without the context of living things. More than 1,000 species of tiny organisms live in or on the mud at the bottom of Puget Sound. In many areas, sensitive species have disappeared. We are left with those that can tolerate harsher conditions. Why are they dying off? What can be done about it?

Some plankton species are becoming more dominant, and the effects on the food web are unknown. When water quality is poor, Jellyfish are displacing forage fish, disrupting the food supply for larger fish.

We know that toxic chemicals are spilling into Puget Sound in stormwater and getting into the food web, first touching the tiniest organisms and eventually causing havoc for fish, marine mammals and humans. Compounds that mimic hormones are affecting growth, reproduction and survival for a myriad of species. Because of biomagnification, some chemicals are having serious effects at concentrations that could not be measured until recently.

Puget Sound can’t cleanse itself by flushing its chemicals and waste out to sea, as most bays do. Puget Sound is long and narrow and deep, and the exchange of water takes a long time. Most of the bad stuff floating in the water just sloshes back and forth with the daily tides.

We can’t forget that some of the good stuff floating around are microscopic plants that feed the food web, along with a variety of larvae that will grow into fish, shellfish and many other creatures. But many of these planktonic life forms are vulnerable to chemicals, which can reduce their ability to survive against predators, tipping the balance in unknown ways.

Understanding water quality is not so much about measuring what is in the water as understanding the effects on living things. Which species are missing from a given area of Puget Sound, and what killed them off?

Biological monitoring has been around for a long time, but we may be entering a new phase of exploration in which we begin to connect the dots between what takes place on the land, how chemicals and nutrients get into the water, and what that means for every creature struggling to survive.

We have some brilliant people working on this problem in the Puget Sound region. I would like to thank everyone who has helped me gain a better understanding of these issues, as I attempt to explain these complexities in my stories.


While I was looking into the sediment story, Maggie Dutch of Ecology’s sediment monitoring team introduced me to a huge number of benthic invertebrates. In a blog she calls “Eyes Under Puget Sound,” she talks about the monitoring program and offers a slideshow of some of the bottom creatures. See also Ecology’s Flickr page.

For some amazing shots of polychaete worms, check out the work of marine biologist and photographer Alex Semenov who took these colorful pix in Russia and Australia.

Plankton bloom in Puget Sound: art on the water

Eyes Over Puget Sound shot some amazing plankton blooms this week, including this one between Bainbridge Island and Seattle. Photo courtesy of EOPS
Eyes Over Puget Sound shot some amazing plankton blooms this week, including this one between Bainbridge Island and Seattle. / Photos courtesy of EOPS

Team members for Eyes Over Puget Sound, a Washington Department of Ecology program, were excited to discover and report on a second major plankton bloom during their flight this week.

Here are a few notes provided in the latest EOPS report, dated June 17, presumably by team leader Christopher Krembs:


“The real show came at the end of the day when we got to Edmonds and started to see a bright orange Noctiluca bloom. It was huge! It persisted all the way to South East Passage. It was the most extensive bloom I have ever seen. Every direction you looked, there it was. It’s as if Puget Sound was on fire!

“The size of this bloom made me wonder … Why is it happening in the Main Basin and not in South Sound? Why is it happening again? Why don’t we know more about its appearance and ferocious appetite for phytoplankton? Could it be that our imprint on Puget Sound is artfully surfacing to remind us of our daily connection to the Sound? Could these large blooms be a clue of a shift in the food chain?”

The report provides all kinds of good information, which I will review more carefully when I get the chance. General observations include red-brown blooms in Port Townsend Bay, Discovery Bay and Bellingham Bay. Large mats of accumulated plankton were seen in Samish Bay. Clusters of jellyfish were spotted in Budd, Totten and Eld Inlets, all in South Puget Sound.

References were made to a previous Noctiluca bloom, which we discussed in Water Ways May 23. Also check out the previous EOPS report.

EOPS provides aerial observations of sea surface conditions between landings, when water is sampled for a variety of conditions. Weather and general oceanographic conditions also are reported after each flight.

Plankton blooms observed throughout Puget Sound

Taken over Winslow on Bainbridge Island, this photo shows a Noctiluca bloom with the Bainbridge ferry in the background. Photo by Christopher Krembs, Ecology
Taken over Winslow on Bainbridge Island, this photo shows a Noctiluca bloom with the Bainbridge Island ferry in the background. / Photo by Christopher Krembs, Ecology

Plankton blooms reported last week from numerous locations in Puget Sound were confirmed and examined from the air Monday by Christopher Krembs and his colleagues at Eyes Over Puget Sound.

The marine monitoring group for the Department of Ecology reported notable Noctiluca blooms, as I reported in a story in Friday’s Kitsap Sun. The blooms are relatively harmless and not unexpected, given the mild weather and freshwater flows that bring nutrients into Puget Sound. They are earlier than in recent years, however.

Christopher also observed heavy sediment flows coming out of the Fraser River near Vancouver and moving south along the Canadian border. These and many other observations can be reviewed by downloading the latest report on Ecology’s website.

A brightly colored plankton called Noctiluca was observed last week along the shore of Bremerton’s Evergreen-Rotary Park. Kitsap Sun photo by Meegan M. Reid.
A brightly colored plankton called Noctiluca was observed last week along the shore of Bremerton’s Evergreen-Rotary Park. / Kitsap Sun photo by Meegan M. Reid.

Pulse of Puget Sound: starting at the bottom

I just completed the second part of a yearlong series I’m writing about the Puget Sound ecosystem and the 21 “vital signs” indicators chosen by the Puget Sound Partnership to measure the health of the sound.

This second part, published in Sunday’s Kitsap Sun, consists of stories about the food web, including plankton and eelgrass; forage fish, including herring; and bulkheads, which are generally considered a threat to the nearshore ecosystem.

I was trying to cover the lower half of the food web, to build a foundation for the other parts to come.


I talked to a lot of experts on these issues and ended up writing one of the largest story packages I’ve ever written. Still, I barely touched the surface of these topics. I guess I’ll have to return later to dig a little deeper.

Scientists often say, the more they know, the more they realize what little they know, or something like that. I’ve always tried to help people understand the complexities of environmental science, but there are no simple answers.

That’s why the Puget Sound Partnership is an important bridge between policymakers and scientists. We have enough tools to know what should be done to save Puget Sound, but how do we know what projects should come before others? What can we afford to do? And how do we measure success or failure? Those are the questions challenging the partnership at the moment.


I would like to thank all the researchers willing to give their time to this project as well as Kitsap Sun staffers who helped crunch the numbers and produce the graphics for the story package, as well as the editors who offered ideas along the way.

The overall series is called “Taking the Pulse of Puget Sound.”
The second part is pulled together on a webpage called “Food web’s base”
Stories in the second part are:
Environment’s health starts at the bottom
The foundation of all life in Puget Sound
Herring, other forage fish, at risk
Eelgrass is both food and shelter
Shoreline armoring threatens base of the food web

Sinclair Inlet last August was awash in colorful plankton. Photo by Christopher Krembs, Eyes Over Puget Sound
Sinclair Inlet last August was awash in colorful plankton. This photo was taken over Port Orchard, looking toward Gorst.
Photo by Christopher Krembs, Eyes Over Puget Sound

Watching the decline of oxygen in Hood Canal

Southern Hood Canal is back to its dirty tricks again, as dissolved oxygen concentrations have dropped to dangerous levels even at the surface. Numerous researchers are watching to see how these conditions play out.

A giant Pacific octopus, which should be hiding, clings to a rock wall Saturday at Sund Rocks Marine Preserve.
Photo by Pat Lynch

The mechanism that causes the oxygen to decline is a little complicated, but it’s pretty well understood. It involves nitrogen, sunlight, plankton, heavy sea water and south winds. See the story I wrote for today’s Kitsap Sun for a brief explanation, or check out a story from April 12, when I described findings from a scientific panel about the sources of nitrogen in the canal.

The graph below shows the oxygen levels at three depths near Hoodsport. As you can see from the blue line, oxygen levels near the surface declined rapidly over the past five days, a period when winds blew out of the south. Levels below 2.5 milligrams per liter are considered highly stressful for sea life.

At Hoodsport, oxygen levels rose at the 10-foot mark starting about midday yesterday. They declined again this morning, starting after midnight. Being close to the surface, oxygen levels in these waters are greatly influenced by winds and waves.

Waters at 66 feet deep stayed low in oxygen but fairly stable, as shown by the green line. Fish tend to swim into shallow waters to avoid those low-oxygen levels. A huge mass of low-oxygen water lies in this mid-range area.

Meanwhile, the low-oxygen waters in the middle layers are being pushed upward by heavy seawater coming in from the ocean. That deep ocean water contains more oxygen than the layer above it, as shown by the red line.

To follow these changes in close to real time, go to the Nanoos website and click on “Click here to view all assets” then on “regions” in the left column and “Puget Sound.” You can get information from most of these buoys. Hoodsport is the closest to the action in southern Hood Canal.

How do we address Hood Canal’s oxygen deficit?

Five years ago, a lot of people were wondering why fish were dying more often in southern Hood Canal during the fall.

Researchers knew that Hood Canal was sensitive to nitrogen. In other words, when nitrogen was introduced to the canal during summer months, nearly all of it was taken up by plankton, which grew into large blooms. When the plankton died, they sank to the bottom, where bacterial decay sucked up the available oxygen.

Beyond that, the questions were numerous: What were the most critical sources of nitrogen affecting the low-oxygen problem? What role does weather and water circulation play? And what can humans do to help the problem — or at least keep it from getting worse.

After a five-year, $4-million study, these questions can be answered with some certainty, as I point out in a story in Sunday’s Kitsap Sun. Now it is time for researchers to convey this information to political leaders and the public, as the Hood Canal Coordinating Council prepares a plan of action.

Scott Brewer, executive director of the HCCC, told me that the eventual plan is likely to include a suite of actions to address nitrogen inputs to the canal, particularly from human sources.
Continue reading

Oxygen in Hood Canal reaches dangerous levels

I hate to be the voice of doom, but low-oxygen conditions in Hood Canal have never been worse — if you can believe the data gathered since the 1950s, alongside more intense monitoring the past several years.

In the southern portion of Hood Canal, you only need to go down about 30 feet to begin to see stressful oxygen levels in the range of 2 milligrams per liter. For current conditions at Hoodsport, go directly to the Hood Canal Dissolved Oxygen Program’s website, which lists data sent back from the Ocean Remote Chemical Analyzer (ORCA).

Sea creatures are beginning to show signs of stress, according to scuba diver Janna Nichols, who described her findings to me Wednesday after a dive in Hood Canal. She talked about fish “panting” as their gills moved in and out rapidly. Some fish, shrimp and other sealife had moved into shallower water. Watch Janna’s video of a wolf eel and other visuals she captured on the dive.

When low-oxygen conditions are that close to the surface, the danger is that a south wind will blow away the surface layer and bring low-oxygen water right to the surface, leaving fish with no place to go.

Of course, I have no desire to see a massive fish kill, but we already know that fish are probably dying in deep water due to the stressful conditions. I collect this information and offer these reports so that people can alert researchers when something happens. Being on the scene when fish are dying could provide important information about the nature of the low-oxygen problem. For details, please check out my stories in the Kitsap Sun Sept. 7 and Sept. 15 as well as the more technical report from Jan Newton on Sept. 7 (PDF 320 kb).

The phone number to report fish kills or oil spills is (800) 258-5990 or (800) OILS-911

If you haven’t heard, the worst low oxygen conditions normally occur in the fall after a summer of burgeoning numbers of plankton, encouraged by nitrogen and sunlight. By fall, much of the plankton has died and dropped to the bottom, where decay consumes the available of oxygen.

While there are plenty of natural sources of nitrogen in Hood Canal, computer models have demonstrated that human inputs from septic systems and stormwater can push things over the edge in the fall.

Officials are hoping that a new sewage-treatment plant in Belfair will begin to reduce the inputs of nitrogen into Lynch Cove. Another treatment plant is being planned in Potlatch. Stormwater upgrades also are being proposed for Belfair and other areas.

In addition to the low-oxygen problem, Hood Canal was closed to the harvest of oysters after people became sick from vibriosis, a natural bacteria that multiplies in warm conditions. See Kitsap Sun story Sept. 10 and Washington Department of Health maps.

The orange triangles represent this year's composite oxygen levels for the south half of Hood Canal. The latest reading, near the end of August, is the lowest ever seen.

Plankton blooms sometimes offer dramatic visuals

We’re getting reports from all over Hood Canal as well as other waterways about plankton blooms that are coloring the water red, reddish orange and other dramatic colors. See the story in today’s Kitsap Sun.

<i>Plankton bloom near Seabeck yesterday</i><br><small> Photo by Don Paulson, Seabeck</small>
Plankton bloom near Seabeck on Hood Canal yesterday (Click to enlarge)
Photo by Don Paulson, Seabeck

Health authorities and researchers are checking to make sure the plankton are not the kind that create toxins that can poison people, pets or sea creatures. So far, reports indicate that most of the plankton belong to the genus Noctiluca, which don’t appear to cause a safety problem.

I’ve heard some great descriptions regarding “ribbons” of color lining the shore in various places. Folks often have trouble capturing the visual drama in a photograph. A rare exception is a picture we received today from Don Paulson of Don Paulson Photography. Paulson says he captured this picture yesterday at his home near Seabeck.

If anyone else has been able to get a good image, please send it along to me by e-mail, and I’ll post the best.