Article Beware! The Blob

Slimy green blob invades the Columbia River in Tri-Cities

By Paul Krupin

Special to the Herald

September 23, 2017 3:21 PM

I was at the boat dock at the west end of Columbia Park watching fellow angler Bill Smith of Kennewick pulling his boat out of the water after spending a few hours fishing for salmon near Bateman Island.

As he peered several feet into the water over the back of his boat, he saw something unusual floating partially in the water at the end of the boat ramp.

“What in the world is that?!” he exclaimed to several other fishermen.

He pointed to an enormous greenish-brown basketball-sized blob of slimy jelly. They got it into a fishing net and hefted the 40- to 45-pound mass onto the shore. It had a translucent body with many star-like blooms along the outside. It could be easily broken into smaller clusters.

I took some pictures of the slimy gelatinous ball of goo, came home and got online.

What he found is called Pectinitella magnifica – a huge colony of micro-organisms called magnificent bryozoans.

According to the U.S. Fish and Wildlife Service, the local sighting comes on the heels of an increasing number of reports in the region of this amazing creature.

Each gelatinous blob can reach several feet in diameter and will turn a dark purple with shiny white spots. Each mass is actually formed out of hundreds to thousands of individual feeding organisms, which extend tiny non-stinging tentacles from the edge of the blob into the water to feed.

While they are as slimy as they come, they don’t sting, are non-toxic, and are not dangerous, although they are capable of causing water outtake pipes to clog.

Scientists think that the increased occurrence in our area may be directly related to climate change and global warming. The warmer waters increase the availability of suitable habitat for the magnificent bryozoan.

Rivers and low-lying lakes with fresh water are seeing increased blooms when the water temperatures reach their peak at the end of the summer.

Scientists are concerned about the increasing abundance in our area. The magnificent bryozoan is a non-native invasive species. It is known to occur naturally in the waters east of the Mississippi River.

The filtering activity of the organisms makes the water clearer, allowing sunlight to penetrate deeper, which can allow more aquatic plants to grow and shift the natural balance of the habitat. And as the magnificent bryozoans invade more habitat, they can disperse rapidly. In the fall, the decomposing colonies produce large numbers of tiny microscopic seedpods called statoblasts that have jagged hooks. They easily attach to the feet of floating birds, who then fly off to populate nearby waters.

“There have been recent occurrences in Vancouver Lake,” said Dr. Stephen Bolling, a researcher at the Washington State University Aquatic Ecology Lab and Professor of Biological Sciences. “Aquatic invasive species pose both ecological and economic threats to the Columbia River Basin.”

This Pectinitella magnifica — a huge colony of micro-organisms called magnificent bryozoans — netted on Bateman Island lived up to the colony’s slimy reputation. Paul Krupin Special to the Herald

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I've seen these all over the place. Lake Washington, this weird little man mad pond in my neighborhood back home.... Always wondered what they were. I threw one at my buddy once. They smell sort of like fish eggs....

Jim Wallace

Smells like low tide.
Looks like a giant waterlogged Kiwi Fruit! If we're lucky, the Nutria might like 'em.

Whoa! I just had another weird thought. Non-toxic...hmmmm....throw 'em in your blender with some rum, and make an exotic drink! Can I have another Bryozo on the rocks, please?:p
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Apparently the article has the genus name spelled incorrectly; it is Pectinatella. They are native to eastern U.S. in calm freshwater lakes and reservoirs, but they have begun to appear in Europe, Asia, and the western U.S. (see You can read more about them here: and Marine bryozoans are quite common and diverse. The white calcareous covering on kelp blades in the late summer and fall is Membranipora membranacea; this bryozoan is an epiphyte, growing on the surface of another organism.
Thanks for the link with more info, Steve. I got a smile reading this line and thinking of @Taxon as "the taxon": "It's as if the taxon is giving taxonomists the proverbial taxonomic finger."