To commemorate the season of all things spooky, gross and disturbing, we’ve compiled a list of some of the creepiest creatures to be found in the waters of the Pacific Northwest.

To kick things off, we dip our toe into the salty waters of the Salish sea, where UW’s Friday Harbor Laboratories (FHL) are situated. These labs make the ideal setting to study the marine world, and provided us with no shortage of horrors to include in this list.

Basket star

Vampires, beware! This incredible creature has no blood, instead achieving gas exchange via its water vascular system.

Rat-tailed maggot

No, that’s not snot. These creatures are able to survive even in the dirtiest environments, such as sewage lagoons or cesspools. You might recognize the name after extensive press coverage in 2017 when they were discovered in the composting toilets at the Glastonbury Festival. Lovely!

Gonionemus jelly

Gonionemus jelly
Gonionemus jelly

While she was on a dive to collect seagrass at FHL, PhD candidate Olivia Graham encountered an array of glorious sea creatures, including the Gonionemus jelly, which is stunning in every sense of the word. Though it may look cool (and somewhat menacing), you’re best keeping your distance, as the Gonionemus jelly has an exceptionally dangerous sting. In addition to the common symptoms of a painful jellyfish sting, the Gonionemus also causes numbness, pain in the arm and leg joints, difficulty breathing and possible liver malfunction.

 

Now it’s time to break out the microscope to peer into the (secret) spooky lives of some of the organisms that are studied by the scientists in the School of Aquatic and Fishery Sciences. Come on down, parasites!

Toxoplasma gondii

toxoplasma gondii
Toxoplasma gondii

Roughly 40 percent of North Americans carry the toxoplasma gondii parasite, which can lead to the infectious disease toxoplasmosis and cause personality changes in their human hosts. Terrifying! Infected people are also three times more likely to get into car accidents. Beware all cat owners and lovers of raw meat — you are especially vulnerable to infection.

Cymothoidae

Cymothoidae
Cymothoidae

This little monster is less of a threat to humans, but we don’t think it’s too popular among our fishy friends. Meet Cymothoidae, a parasite found in marine and freshwater environments. This crustacean eats its host fish’s tongue, causing it to atrophy. Once the tongue is gone, the parasite lays down inside its mouth and pretends to be a tongue. Not cool, dude.

 

Finally, allow us to introduce you to a nightmare for oyster farmers, courtesy of our colleagues at Washington Sea Grant.

Ghost shrimp

ghost shrimp
Ghost Shrimp in Willapa Bay

It may not look particularly menacing, but the ghost shrimp’s impacts on the environment can be terrifying. In large numbers, ghost shrimp churn up sediment to feed on algae and microbes. In the case of shellfish farms, this leads to mud beds softening, and causes shellfish growing on the estuaries to sink and suffocate. Here in Washington state, Washington Sea Grant is working with tideland managers, shellfish growers and regulators in Grays Harbor and Willapa Bay to find ways to manage these creepy critters.

 

What would you add to this list? Tweet us @uwenvironment with your creepiest, grossest or most wacky creatures this Halloween!