Sweet Days of Summer, the Algae's in Bloom

Harmful algae bloom. Kelley's Island, Ohio.

Algae can be pesky. We’ve talked previously about dead zones, where microorganisms like algae in a eutrophic environment can deplete the water’s oxygen, causing aquatic animals to die. And last year we told you about algae poisoning drinking water in Toledo, Ohio. Right now, scientists are evaluating what might be the largest toxic algal bloom ever on the west coast of the US, which has shut down the shellfish industry there. Algal blooms are a naturally occurring phenomenon, but climate change and nutrient runoff are making the problem even worse.

With climate change, we can expect higher sea surface temperatures, which is what is happening along the Pacific Coast now. The water temperature off of California is 4 to 7 degrees warmer than usual. This warm water, affectionately dubbed the ‘warm blob,’ is carrying red crabs, jellyfish and other warm water creatures with it. The warm water may also be linked to this latest toxic algal bloom. The bloom is being called “unprecedented” in terms of its extent and magnitude but researchers still need to study the marine ecosystem there to see how much the warm water is related to the scope of the bloom. If they are indeed linked, climate change could be very bad news for the West Coast shellfish industry and the creatures that call that part of the world home.

While climate change remains a tough and complex nut to crack, another component of the toxic algae phenomenon, nutrient runoff, is far more clear-cut. Nutrients, primarily nitrogen and phosphorus, come from a variety of sources: agriculture runoff, stormwater, wastewater, burning fossil fuels and household products. While some nutrients are naturally occurring, sources from human activity can overload water bodies, causing algal blooms that can create dead zones and toxins, depending on the species of algae.

At home, most of us contribute to nutrient runoff. Lawn fertilizers can wash off your grass and end up in local water bodies, and old septic systems can leak nutrients into the ground. In coastal places like eastern Long Island, septic systems are quite problematic. Algae expert Dr. Chris Gobler estimates there are 360,000 septic tanks in need of replacement in the area.

Nutrients also abound in the agricultural sector. Fertilizers help plants grow, but they can do the same for algae when they’re washed off the field and into the water. Livestock, dairy and poultry operations create a lot of nutrient rich manure than can be used as fertilizer, but if manure makes its way off the farm it can help fuel algal blooms.

We’re keeping our eyes on algal blooms this summer in hopes that we won’t have a repeat of last year’s story in Toledo, where algal toxins left the area’s tap water undrinkable. To stay up to date, our friends at Resource Media are maintaining Toxic Algae News (on twitter: @toxicalgaenews) where you can find the latest information on blooms across the country.

This summer check out these actions you can take to cut back on nutrient pollution:


Image “Harmful algae bloom. Kelley's Island, Ohio. Lake Erie” by NOAA Great Lakes on Flickr used under a Creative Commons Attribution 2.0 Generic license.