Anoxic Oceans, Biotoxins and Harmful Algae — Missing Links in Mass Dolphin Deaths on US East Coast?

Dolphin Strandings

(East Coast Dolphin Strandings by State and Year. Image source: NOAA)

According to reports from NOAA, as of early October more than 550 dolphins had died and washed up along the US East Coast. The deaths, which NOAA has causally linked to morbillivirus infection, are occurring at a more rapid pace than the massive 1987 die-off which eventually resulted in more than 1100 East Coast dolphin deaths over the course of a 1 year period. By the time the first three months had passed in the 1987 die-off about 350 dolphins had perished. If the current event lasts as long as the 1987 die-off we could possibly see nearly 2000 deaths, setting up the current event as the worst in modern memory.

Morbillivirus — Cause, or Symptom of a More Ominous Problem?

In recent calls to NOAA and the various state institutes of marine science, I continue to receive confirmation that morbillivirus is listed as the primary cause of dolphin deaths. Most of the stranded dolphins have tested positive for morbillivirus and the disease has been implicated in dolphin deaths before. (For reference, morbillivirus is the same disease that causes measles in humans and is similarly virulent in dolphins. )

That said, numerous scientific sources, including The Scientific American and researchers at the NRDC, have questioned whether morbillivirus is the primary cause or just a symptom of a larger problem with ocean health. They point to research showing stranded dolphins with high levels of biotoxins in fatty tissue and individuals that are generally plagued by parasites and other infections. Many of these dolphins display compromised or weakened immune systems as a result of elevated toxicity levels. Meanwhile, a large enough segment of these animals are among the adult population to rule out age as a major secondary cause of mortality.

Algae Blooms as Source of Biotoxins

East Coast Algae Bloom

(Satellite Shot of Green and Brown Tinted Water Indicative of Algae Blooms off the Virginia Coast on Oct 18. Image Source: Lance-Modis)

Sitting on the top of the food chain as one of the oceans’ high-order predators, dolphins consume a large volume of fish. These fish, in turn, are fed by lower food chain sources. As food passes up the chain, any toxin within the food will reach higher levels of concentration, making top order predators, like dolphins, more vulnerable to poisoning.

The biotoxins found in recently deceased dolphins can be linked to harmful forms of algae that tend to develop in low oxygen ocean environments. Some of these toxins can cause various forms of food poisoning in mammals (including humans). Others, like hydrogen sulfide, can build up in adipose tissue to have a number of long-term effects resulting in stresses to major organ systems, neurological and psychological health, and strains on a body’s immunity to disease and infection.

Most of the dead dolphins discovered, thus far, are either males or nursing infants. Both are more vulnerable than females to toxicity due to the fact that males have no means of rapidly shedding biological toxins and infants receive higher doses of harmful substances from toxins concentrating in mother’s milk.

Fasting Dolphins Likely to be More Affected

As toxins build up in the dolphins’ fatty tissues, they come under increased risk of immuno compromise and infection during times when they tap the energy from these stores. Elevated toxicity can happen any time a dolphin may decide to fast rather than forage. As the fats are tapped by the body, the toxins are re-released into the dolphin’s blood stream where they can build up to harmful levels.

Morbillivirus Shouldn’t be So Lethal

Supporting the biotoxin/immuno compromise theory is the fact that morbillivirus shouldn’t carry such a high lethality rate. The virus normally only results in death among the most vulnerable individuals — primarily the very young, the very old, or the already weak or sick. The fact that morbillivirus, in this case, is carrying such a high lethality rate is a direct sign that the virus isn’t the only cause and that a higher portion of the dolphin population is far less healthy than is usual. High biotoxin levels in dead dolphins also point toward a combination of causes.

Dying Oceans and Dying Dolphins

A recent report on the health of the world’s oceans resulted in ominous findings that may also provide further hints as to why so many East Coast dolphins are dying this year. The IPSO 2013 State of the Oceans report found that oceans were experiencing anoxia (loss of oxygen) not just along coastal regions where human nutrient run-off was resulting in massive algae blooms and dead zones, but also in the deep ocean. There, in even the far off-shore waters, ocean oxygen levels were falling. Other high order predators, requiring high oxygen levels to sustain their high metabolisms — like the deep sea marlin — were found to have changed their migratory patterns to avoid deep ocean, oxygen-poor, dead zones forming and expanding throughout the world’s oceans.

The expanding anoxia is both an ocean killer and a direct signal of the changes resulting from human caused climate disruption. Warmer ocean waters hold less oxygen in solution and so they dump more into the atmosphere. In addition, increased fresh water run-off from melting glaciers and more intense rainfall events (due to increases in the world’s hydrological cycle directly caused by warming), result in less mixing of surface waters and deeper waters. Increased run-off also results in more algae blooms which further starve the oceans of oxygen.

These all contribute to increasingly anoxic waters. And once the ocean environment flips to anoxic states, it becomes a host to numerous toxin-producing bacteria. These toxins, in turn, end up in the food chain and directly impact the dolphins and a whole host of other animals.

In other words, a more anoxic ocean is an ocean that produces more harmful bacteria. An ocean full of harmful bacteria is one that increases the risk of dolphin mortality. And when we see spikes in dolphin deaths, as we have on the US east coast this year and on the US gulf coast for every year since 2010, we had better sit up and pay attention. As it’s a clear signal that the oceans, as a whole, are in trouble.

Implications for Both Ocean and Land Dwellers

Because the ocean and the atmosphere are interconnected and because humans greatly rely on the oceans for both foods and livelihoods, it is pure folly to ignore the ongoing plight of the world’s oceans. Toxic fish, mass deaths of ocean animals, and a thinning of the ocean biosphere could result in the loss of enough food to feed upwards of a billion people. Increasing instances of toxic algae blooms will also likely result in higher sickness and mortality rates for those who frequently come into contact with the seas. In the most extreme cases, blooms of hydrogen sulfide producing bacteria could poison the air near toxic algae blooms, resulting in severe hazards for those who live on land.

Transitioning to a stratified, anoxic and/or Canfield ocean state is an outcome of climate change that is all too often ignored. A risk that should be listed among the worst potential outcomes of human greenhouse gas emissions. A risk that has echoes in the great Permian Extinction event in our world’s deep past. It is a danger exists now and the growing risk of its emergence are becoming increasingly apparent.

Signal Received?

The dolphins, our ‘sentinels of ocean health’ are dying. And in their deaths are a message that we should be hearing loud and clear. Will we listen?

Links and Hat Tips:

The State of the Oceans, 2013

Are Dolphins Reaching a Breaking Point?

Are Humans Behind the East Coast Dolphin Die-Off?

Climate Change, Anoxic Waters and Dead Dolphins

Hat Tip to Commenter Steve

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Climate Change, Algae Blooms, Anoxic Waters and Dead Dolphins: What’s Killing East Coast Dolphins? Morbillivirus? Or Something More Ominous?

Oily Algal Sheen

Oily algal sheen of red, black, and green visible from Cape Hatteras to New Jersey in MODIS satellite shot on August 12, 2013.

(Image source: NASA/MODIS)

Because dolphins sit at the top of most ocean food chains and due to their sensitivity to healthy or unhealthy ocean states, they have been called “the sentinels of ocean health” by oceanographers around the world. So, when East Coast dolphins are dying at their fastest rate in 26 years, and with scores of these majestic creatures washing up on beaches from Virginia Beach to New York, we should sit up and pay attention.

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I remember the 1987 East Coast dolphin die-off well. Why? Because I can clearly recall paddling through the ugly, murky red-stained waters in my almost daily surfing quest for decent waves as a Virginia Beach teenager. It was early September and school was just beginning. The tropical Atlantic was unloading its guns, firing off the tropical storms and hurricanes that provided the lovely swells I hunted with so much passion.

But walking down the beach didn’t provide its usual pleasure. The air was chill and the ocean ugly. Plunging into the water, I noticed it was filled with what appeared to be a reddish mud. Even knee deep, I couldn’t see my feet. Paddling out through the dark, rust-red waters was strange, eerie, like entering a distant land or the seascape of another time. The water was cold and nutrient-rich from a large upwelling event as well as from the annual run-off from farms and lawns. Distantly, I knew these things from news reports and from the discussions of family members who were, even then, heavily involved in the Chesapeake Bay Foundation’s efforts to preserve the health of marine environments local to my area.

But paddling through those ugly waters, I was more concerned about what I couldn’t see. About what was concealed beneath all the darkness and murk. Where had the crystalline waves of my early youth gone? And what of the azure waters full of rich, white foam? Now turned to a kind of brownish scum.

The waves that day were large, dark, bullies filled with a biting ugliness. Angry brutes capped with rusty foam. One held me under for longer than I liked and I turned to paddle home. Settling in front of the TV glow with my family, I learned the news. “Largest Red Tide on Record. Massive East Coast Dolphin Deaths. Health Risk. Advised to Stay out of Red-Brown and/or Murky Water.”

My family kind of laughed it off. There’d been red tides before. But none like this one. That year the red tides were exceptionally strong and over a ten month period more than 700 dolphins died.

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These events of long ago remain clear in my mind because they had ominous implications for my favorite sport — surfing — which in itself was rooted in a joy for the glory of nature. I had often felt that the great symphony of life and beauty I found in the ocean while surfing contained far more majesty and spirituality than any land-bound church. The great blue vault of heaven and the starry night that came behind contained all the awe and adoration, for me, that so many others associated with God. My worship was a dance across the beautiful face of nature, my only remaining contact with the human world — the opalescent surf board beneath my feet.

But with the red tides the beauty and the awe was ripped away, revealing a dark and ugly underbelly. A soulless place of lost life and beauty. I didn’t want to plunge myself into ugly and potentially harmful waters, nor did I find much appeal in those new, dark, blood colored waves. They had lost their grace, becoming rough, brutish things and the water I was paddling through was death. Along with the dolphins, fish, crabs, every sort of sea life suffered and perished. The catches of fishermen dwindled. It was a bad year, but only a shade of things to come.

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Silence and an incapacity to communicate or understand what is wrong is often the most brutal form of suffering. During my middle-school and high school years, I suffered numerous bouts of bronchitis and general weakness. During late high school, I went through a six month period when I experienced terrifying episodes of shortness of breath, with no other symptoms. Doctors couldn’t discover anything wrong, so I continued on as I could. The summer after my senior year, I was sick with a fever of 100+ for a month straight. The doctors tested me for mono and found nothing. Shrugging their shoulders, they proclaimed it was a ‘mono-like-virus.’ Whatever had caused these symptoms left my organs inflamed and my doctors advised me to ‘avoid any kind of strenuous sport or heavy lifting’ lest it cause an organ rupture. For more than a year, I required 10 hours of sleep to maintain any level of energy. Eventually, though, the health troubles and symptoms faded.

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Thunderstorm over Jane Island.

Thunderstorm over Jane Island.

I come from a place that relies on the life of the ocean and the waterways that feed her. And my experiences have taught me to be sensitive and to pay attention to my surroundings. Often, the media cannot be relied upon to tell the whole story. Such was the case with the camping trip I took to Jane Island with my wife this summer.

The Jane Island campground is a thin strip of coastal pinewood carved into a cluster of sites for campers, RVers and wildlife enthusiasts. It is managed by the park service and sits adjacent to a sprawling wetland called Jane Island. The island is, itself, a testiment to the ravages of human caused climate change. More than a hundred years ago, the island hosted a fish cannery, and a number of farms. But the low lying land, like so many Chesapeake Bay Islands, has steadily been reclaimed by rising water. Now all that remains are a few copses of pine trees and a vast wetland filled with channels deep enough to kayak through. At high tide, the majority of the island is now submerged.

Kayaking Through the Wetlands of Jane Island

Kayaking Through the Wetlands of Jane Island (My Sister and Bro-in-Law in this Shot)

The nearby town of Crisfield had its own tale to tell. Dilapidated and abandoned houses lined the road leading into a town filled with closed store fronts covered in peeling or salt-stained paint. The architecture there appeared to have frozen sometime between the late 80s and late 90s. Everywhere could still be seen the icon of Crisfield — images and silhouettes of Chesapeake Bay blue crabs displayed everywhere from flags bearing school mascots (“Go Crisfield Crabs!”), to flags displayed outside dilapidated real estate offices, to paintings on the sides of buildings, to signs on the dwindling number of bay side restaurants. A ferry that transported tourists and sightseers to Tangier Island, which is also steadily being reclaimed by the Bay, lies roped off and idle, blocked by large orange traffic cones.

The scene is one of a town that is descending into a post apocalyptica, one more likely to be featured in a gritty novel or Hollywood movie than as a destination spot for vacation goers.

What had pushed Crisfield so far down the road to disintegration? One need look no further than their iconic blue crab. Crisfield is a town almost entirely supported by its crab and oyster fishing industries. But over the past 26 years, both crabs and oysters have suffered from a series of disasters. Red tides, algae blooms, anoxia, invasive species, and chemical dumps from industries along rivers feeding the bay all exacted their awful toll. The result was numerous deaths and high toxicity levels in these sensitive bottom dwelling animals that either made them unsellable or substantially reduced their populations for extended periods. And, in Crisfield, this devastation of ocean bottom dwelling life took a terrible and visible toll on human life there as well.

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Why Context is So Important to Understanding Climate Change

In understanding the damage resulting from human caused climate change, context is everything. Because climate change is so large, we have to look at the big picture in order to understand it. All too often, we look at a long, thin, bushy, tufted thing, or a padded stump-like thing, or a spear-like protrusion of ivory and see only strange, isolated, and seeming in-congruent features. But when drawing back, what we find is an elephant.

And this is why I’m sharing with you my experience of the health of the waters surrounding the Chesapeake Bay, a set of waters I have had intimate contact with for most of my life, intimate enough to know that the life there is in severe crisis. So when scores of dolphins begin washing up dead on shores adjacent to the Chesapeake Bay and nearby ocean, one does not immediately jump to conclusions without investigating the larger context.

So, before we continue on a broader investigation, I’d like to call your attention once again to the satellite image at the top of this blog post and ask you to engage your senses. What do you see there? And does it look normal to you?

Morbillivirus or Failing Ocean Health?

Earlier this summer odd reports were emerging that Manatees were dying in unprecedented numbers along Florida waterways. Widespread red tides had expanded through Florida estuaries, coating the grasses Manatees consume in paralytic toxins. These toxins, when consumed in large enough amounts cause the Manatees muscles to seize up, making it impossible for the Manatees to reach the surface to breathe. From NPR as of March 28th:

More than 200 manatees have died in Florida’s waterways since January from an algae bloom called red tide, just as wildlife officials try to remove the marine mammal from the endangered species list.

In a separate incident during early June, reports had emerged that a large algae bloom was covering some East Coast beaches with an algal foam that is implicated in increasing ocean anoxia. From the Marine Institute as of May 27th:

The Marine Institute is currently monitoring an algal bloom on beaches on the east coast of Ireland as a part of its Phytoplankton Monitoring programme. The bloom was detected on May 27th  using satellite images and information provided by the Envirnomental Protection Agency and Wexford County Council.

The production of foam, and in some extreme cases anoxia, can result in marine organism mortalities. Fish mortalities caused by this particular species in previous Irish blooms have not been observed, as wild fish tend to avoid the bloom. This may explain the low catches reported by sea anglers on the east coast in recent weeks.  Several fishermen have also reported clogging of nets in recent weeks, which may be caused by the decaying bloom sinking to the seafloor.

In yet one more incident, an estuary of the Chesapeake Bay called the Lafayette River in Hampton Roads experienced yet one more dangerous red tide event. The Chesapeake Bay foundation reported the event which is under investigation by the Virginia Institute of Marine Science.

The findings match visual evidence of wide-spread algae blooms that can be seen from satellite in this region of the East Coast. And algae blooms can have numerous and devastating effects to marine ecosystems. The organisms involved in algae blooms often produce toxins which are directly dangerous to fish and marine wildlife. They starve the waters by consuming oxygen, at which point the oxygen consuming algae die and micro-organisms that thrive on anoxic conditions multiply. These organisms produce and use hydrogen sulfide as a means of cellular respiration increasingly as anoxic conditions expand. Hydrogen sulfide is a fat-soluble gas that is toxic to all forms of oxygen dependent life. It may become concentrated in both fish, mollusks and crabs. In high concentrations in mammals hydrogen sulfide is implicated in high fever, pneumonia like symptoms, multiple organ systems stress (including liver and kidneys), and is a potent neuro-toxin — attacking both nerve and brain function. LD 50 levels (the dose which is lethal for half the population) for most mammals are around 5 grams per kilogram. Direct inhalation of extraordinarily high levels of hydrogen sulfide acts similarly to cyanide gas and is almost immediately lethal.

Both anoxia and high hydrogen sulfide levels have been implicated in numerous fish kills occurring around the world as both oceans and inland waterways warm and become more favorable to large algae blooms. Such a change in ocean and water states has been implicated in numerous mass extinction events in the oceans and, in worst cases, on land (see The Deadly Climb From Glaciation to Hothouse, Why the Permian Extinction is Pertinent to Human Warming).

Finally, it is important to note that of the now 200+ dolphins that have washed ashore dead, only 3 have tested positive for morbillivirus.

Dolphin Die-off Stretches Virginia Aquarium Resources

(Video embed code isn’t working, looking for alternate source. Until then, please follow link)

As the above video shows, oceanographers and marine scientists at the Virginia Institute of Marine Science aren’t buying the morbillivirus explanation.

Perhaps the most stark evidence for a non-virus related death source, an indication of fat soluble toxins of the kind produced by large algae blooms, is the fact that those individuals most vulnerable to toxins are the ones that are seen to be dying at the most rapid rate. According to Smithsonian Institution scientist, Charlie Potter:

“Males don’t have a mechanism for shedding contaminants. The females shed significant amounts of their lipid-soluble contaminants through lactation, so the calf gets a hell of a dose early on in life, and some of the most outrageous levels of contaminants we’ve seen have been in calves.”

Susan Barco, also a scientist with the Smithsonian, noted that dolphins were a key indicator of ocean health and that when dolphins are dying in large numbers, something is seriously wrong:

“Bottlenose dolphins are a higher-order predator. They’re often referred to as ‘ocean sentinels of health.’ So when our bottlenose dolphins are healthy, it would probably indicate that we have a fairly healthy ecosystem. When our bottlenose dolphins are not healthy, it may very well indicate that our ecosystem is not healthy,” she said.

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The ongoing loss of ocean health is, to me, a defilement of the very spirit of our world. As a child and teen, I was part ocean creature, with so much salt water in my veins. My first memories of her include my father joyfully tossing me into the, then crystalline, waves and then swimming in after me, taking me to the depths to cup small black fish in his hands as a gift of experience to my two-year-old self.

The moment of the black fish, swimming in my father’s hands, me staring at it, it looking back at me, so small, even compared to me, is still with me. I remember being afraid for the fish cupped in the large hands of my father. I remember thinking it might be hurt. Yet I also remember the wonder of the moment we shared, and the joy I felt as my father released it back to the waters.

I realize now that the life of the fish and my own life are connected and that they were never separate. The fish depends on me and my human fellows to act responsibly, to work to restore a now terribly sick world, to give it back the more healthy ocean of my childhood. And we, both you and I, depend on the fish to live, to do its good work in doing its own part to keep the oceans well, a safe place for humans and ocean dwellers alike. For together we become a part of a vibrant and self-reinforcing web of life. And, in breaking that web, we come to die alone and with great suffering.

I do not like this mass death of the dolphins whom we now know to call to each other across the oceans by name and with voices that carry through miles and miles of the still living, but greatly threatened, waters. And I am growing deeply tired of a great number of humans who obstinately fail to see the bigger picture, who continue to push for the delivery of ever greater harm and yet deny its growing force and violence. If the dolphins have names for one another, I wonder if they also have a name for such creatures that live among us?

***

Destroyer of oceans, destroyer of life, destroyer of worlds…

Links:

Dolphin Die-off Stretches Virginia Aquarium Resources

Algae Bloom in the Chesapeake Bay

Dozens of Dying Dolphins Preview Environmental Disaster

Anoxic Event

The Deadly Climb From Glaciation to Hot-House: Why the Permian Extinction is Pertinent to Human Warming

Algae Bloom Kills Record Number of Manatees off Florida

Algae Bloom Detected on East Coast Beaches

Hydrogen Sulfide in Drinking Water

Hydrogen Sulfide Exposure in an Adult Male

Toxic and Harmful Algae Blooms

UNESCO Report on Algae Blooms

Dolphin Deaths Alarm Scientists

Dolphins Dying by Dozens Along East Coast

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Interesting fact: do a spell check on Morbillivirus and what do you get?

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