The Worst Bay Area Algae Bloom in Over a Decade Reintroduced Us to This Prehistoric Creature

Not-so-fun fact: Sturgeon are the ‘most endangered group of animals — on earth.’

The massive Bay Area algae bloom that claimed tens of thousands of native fish earlier this month was the largest of its kind since 2004. This “red tide” actually began taking shape in July, causing otherwise blue water to turn a murky, opaque shade of orange. As it grew — and, thus, became more dangerous — somewhat alarming fish die-offs started being reported in mid and early August. And by September, the algae boom had reached unprecedented levels, causing a region-wide fish die-off not seen in nearly twenty years.

Multiple factors created this red tide — warmer than usual ocean temperatures, increased amounts of sunshine, plastic pollution, literal feces and urine runoff fueling explosive microbe growth — all of which created fertile water for Heterosigma akashiwo, the species of toxic algae responsible for the bloom, to produce. And as their numbers grew unchecked, so did the amount of oxygen they consumed. 

Alas, aquatic life that relies on oxygenated water, like bat rays and striped bass, suffocated amid low levels of oxygen and high concentrations of carbon dioxide.

One of the animals to wash up in alarming numbers was sturgeon: large dragon-looking bottom-feeders that can weigh hundreds of pounds and stretch longer than a Honda Civic.

Fortunately for us in the Bay Area, we have not one, but two native sturgeon species that call our waters home — the green sturgeon (Acipenser medirostris) and white sturgeon (Acipenser transmontanus). Both share distinctive rows of osteoderms, which are the bony scutes that run the length of their bodies and give them that almost crocodilian look. In fact, among the largest sturgeons ever recorded each weighs in excess of 1,500 pounds and can rival the sheer size of crocodilians. Here in the San Francisco Bay Area, the largest sturgeons ever recorded were all around 350 pounds. 

Green and white sturgeon are remarkable in that they can live upwards of 70 years old. Unlike us mammals, they have indeterminate growth; this means they can continue lengthening and widening past maturity; humans possess what’s called determined growth — our genetics, diets, and environments all dictate how tall and wide our skeletons can get up until we’re adults. 

Sturgeon biology basically says omg, that’s cute bipedal primates, we’re gonna keep on vibing and growing, btw.

However, like humans, sturgeons take a comparatively long time to reach reproductive ages. Depending on food supplies and environmental stressors, green and white sturgeon can take anywhere between 15 and 25 years to spawn. 

And the two to three million unfertilized eggs females carry with them come mating season? That’s caviar, babes. 

(Traditional harvesting practices are archaic and can require the decades-old female fish to be gutted, but new-age sturgeon farms are using different methods that extract the eggs by way of manipulating them through the female’s vent. This saves the female and also produces better quality eggs; fish release a rush of cortisol and endorphins when they’re about to die, which can, in fact, alter the flavor of the eggs.)

Despite surviving on this planet for well over 100 million years, the biggest threat to sturgeons is… well, us: a species that’s been around for just 300,000 years. As Bay Nature noted, commercial fishing for sturgeon in the Bay Area boomed in the 1860s and by 1901, stocks were nearly wiped out. It wasn’t until the commercial banning of sturgeon was made into law in 1917 that the fish could begin recovering in numbers. 

Since then, both sturgeon species have continued to experience population growth. But their numbers are still a fraction of their former figures; the International Union for Conservation of Nature has listed the green sturgeon as an “endangered,” while the white sturgeon is considered more stable but still “vulnerable” to extinction. In fact, all but two of the twenty-eight extant species of sturgeon are experiencing increases in population counts. The vast majority continue to suffer population declines. It’s the very reason why sturgeon, as a whole, are considered the most endangered group of animals — on earth. That’s fucking wild (and should exist as a call-to-action to save them from our own doings against the planet).

If we don’t want to see these cartilaginous fish (that have conical snouts, allowing them to consume food like young salmon, crayfish, or fish carcasses) go the way of the dodo bird, we have to get a handle on the climate crisis. Habitat loss and disgusting waters continue decimating sturgeon populations in the San Francisco Bay estuaries where they live and spawn.  

Thankfully, the worst of this algae bloom appears to be over, according to San Francisco Baykeeper, a local marine conservation group dedicated to safeguarding the aquatic flora and fauna in the region. However, it’s left in its wake “dead zones” that could take months, if not years to fully recover.

We need to change the direction of the tide regarding their population figures — and not, say, fuel circumstances where it instead darkens with suffocating algae.

Leave a Reply