Eyes Under Puget Sound: Critter of the Month—Bloodworms

Left: Dany identifies marine critters at the South Sound BioBlitz on August 11, 2018.

Center: Glycera americana, a species found on both the east and west coasts, has finger-like gills that shoot out from behind its feet.

Right: Our 2016–2017 WCC intern, Nicole Marks, holds a Glycera robusta specimen freshly collected from a benthic grab sample.

It’s a Bioblitz!

Recently I had the pleasure of volunteering at the South Sound BioBlitz, a community outreach event hosted by the Pacific Shellfish Institute. Participants spent a rainy Saturday morning working with local scientists conducting beach surveys to find intertidal invertebrates. Most species were catalogued in the field, but some specimens were brought back to the WET Science Center for closer examination. It was a great way for folks of all ages to get up close and personal with Puget Sound’s benthic (sediment-dwelling) invertebrates!

One of the most common finds at our survey location was a small, pink, wiggly worm with a pointy head. I immediately recognized it as a bloodworm because of its paper thin skin that reveals its red body fluid inside.

Bloodworms are a type of polychaete, or marine segmented worm, in the family Glyceridae. The intertidal species are only a couple of centimeters long, but we get a much larger version in our Puget Sound subtidal benthic grabs that can be over a foot long (see video below for one of these big beauties)!

In cold blood

I often get the question, “Do bloodworms bite?” Well, yes and no. The bloodworm is a voracious predator and has a long proboscis, or mouthpart, that can shoot out of its body like something in a horror movie. At the end are four black jaws that are connected to venom glands. Despite their sinister name, bloodworms typically save their venom for the tiny crustaceans they like to eat. They don’t usually harm humans intentionally, but if you did happen to put your finger near the worm’s mouth, you could end up with a minor bee-sting-like bite.

The bloodworm’s black jaws are especially strong because they contain a copper-based mineral that makes them almost as hard as human tooth enamel—an important quality when you are munching on sand grains with your food!

Blood in the water…and in the mud

When you take a bloodworm out of its habitat, it will thrash around like a fish out of water (see video below—watch for the proboscis shooting out). This makes them great for attracting actual fish, which is why fisherman commonly use them as bait. Don’t confuse them with the popular aquarium fish food; those small red freshwater bloodworms are actually midge fly larvae.

In addition to their usefulness to humans, bloodworms provide an important ecological service. They are highly mobile, burrowing into the sand or mud with their pointed snouts. This activity is called bioturbation, or mixing of the sediments, and it allows much needed oxygen and nutrients to penetrate into the deeper layers of sediment. The burrows made by the worms can also provide habitat for smaller critters, helping drive biodiversity. Bloodworms may not be beautiful, but Puget Sound sediments would certainly be a less productive and interesting place without them!  

By: Dany Burgess, Environmental Assessment Program

Our benthic taxonomists, Dany and Angela, are scientists who identify and count the benthic (sediment-dwelling) organisms in our samples as part of our Marine Sediment Monitoring Program. We are tracking the numbers and types of species we see in order to understand the health of Puget Sound and to detect any changes over time.

Dany and Angela share their discoveries by bringing us a Benthic Critter of the Month. These posts will give you a peek into the life of Puget Sound’s least-known inhabitants. We’ll share details on identification, habitat, life history, and the role each critter plays in the sediment community. Can't get enough benthos? See photos from our Eyes Under Puget Sound collection on Flickr.

Eyes Under Puget Sound: Critter of the month – Common Sun Star

Crossaster papposus; photo courtesy of Neil McDaniel,
http://www.seastarsofthepacificnorthwest.info/index.html

Getting ready for the Aug. 21 solar eclipse? Well, this month’s critter was born ready. The Common Sun Star goes by many common names – Rose Star, Spiny Sun Star, Snowflake Star – but no matter what you call it, there’s nothing common about Crossaster papposus. We think it is out of this world!

Total eclipse of the star

With its bright sun-like appearance, the Common Sun Star is one of the more beautiful creatures in Puget Sound. Individuals can be all one color but generally vary in color and pattern, with some featuring pink, white, orange, and yellow rings.

A star is born

Common Sun Stars can grow to an impressive 14 inches or 34 centimeters across – larger than a dinner plate – but they also grow slowly, taking 10 years to reach maximum size. As small juveniles, they prefer shallow subtidal habitats; as adults they migrate to deeper waters, down to 1,200 meters in depth. This explains why we rarely encounter them while sediment sampling, although they occur from Alaska to Puget Sound – as well as the north Atlantic coast).



Two Common Sun Stars with different color patterns; photo
courtesy of Dave Cowles at https://inverts.wallawalla.edu/

Well-armed

The Common Sun Star has more arms than the typical five-armed sea star that's familiar to most of us. Resembling the sun for which the family Solasteridae was named, it has many pointed ray-like arms originating from a broad central disk. Some sea stars have as few as eight or as many as 16 arms. For this species, the magic number of arms is almost always 11. It, too, can regenerate, or grow back, missing or damaged arms if the central disc remains intact.

Close up of pseudopaxillae on top surface of a
preserved Crossaster papposus specimen.

A spine in the sand

Even if the Common Sun Star didn’t have a unique shape and color, it has plenty of distinct features that taxonomists like us can use to identify it. Its dorsal – or top – surface is covered with little hedgehog-like bundles of spines called pseudopaxillae. The mouth (located on the animal’s underside) is bare and surrounded by long spines, and there are two rows of sucker-tipped tube feet running down each arm. It also lacks pedicellariae, tiny pincer-like defense organs that many other echinoderms possess. 



Common Sun Star goes into attack mode;
photo courtesy of Neil McDaniel
 http://seastarsofthepacificnorthwest.info/index.html

Here comes the sun (star)

A dominant and agile predator, the Common Sun Star scoots across the sediment at 70 centimeters a minute, using sensory chemoreceptors to “smell” when a potential prey animal is near. While the Common Sun Star wouldn’t quite beat the Sand Star (Luidia foliolata) in a race, it has several other advantages over its speedy relative. By standing on the tiptoes of its tube feet, it can make itself tall enough to cover and engulf its prey.

Can you put your stomach outside your body to eat a big meal?  Well this star can. It has an eversible stomach, which means it can turn its stomach inside out, shooting it out through its mouth. This gives the Common Sun Star the ability to handle the larger prey items it likes to munch such as sea urchins, other sea stars, and clams.  When it appears with a big hump, you know it’s enjoying a big meal.

A brighter future?

In 2013, scientists in Washington State discovered sea stars that appeared to be wasting away and dying from a mysterious disease. We now know that Sea Star Wasting Syndrome is caused by an ocean virus, and it has wiped out millions of sea stars on the Pacific coast. Although Crossaster papposus is not one of the species hit the hardest, a few cases of wasting Common Sun Stars have been documented in British Columbia, and they are listed as “likely affected.” Keeping our fingers and arms crossed that sea star populations will rebound and thrive on our coast once more.

Critter of the Month
Our benthic taxonomists, Dany Burgess and Angela Eagleston, are scientists who identify and count the benthic (sediment-dwelling) organisms in our samples as part of Ecology’s Marine Sediment Monitoring Program. We are tracking the numbers and types of species we see in order to understand the health of Puget Sound and to detect any changes over time.

Dany and Angela share their discoveries by bringing us Critter of the Month. These posts will give you a peek into the life of Puget Sound's least-known inhabitants. We'll share details on identification, habitat, life history, and the role each species plays in the sediment community. Can get enough benthos? See photos from our Eyes Under Puget Sound collection on Flickr.

Eyes Under Puget Sound: Critter of the Month – The Moon Snail

Lewis’ Moon Snail with its dark brown, hard operculum.
Courtesy of Linda Schroeder- PNW Shell club.

With its easily recognizable shell (the largest found on Puget Sound beaches), we are certainly over the moon for this month’s critter: the Moon Snail.

Full moon

When we talk about moon snails, we are referring to a group of species within the family Naticidae.

Here in the Pacific Northwest, we see a few different species. Lewis’ Moon Snail is the largest of the moon snails -- it can grow to 14 cm! Although it is the most common species overall, we don't often encounter Lewis' Moon Snail during our subtidal Puget Sound sediment monitoring because it lives in intertidal habitat.

The Pale Moon Snail and Arctic Moon Snail are more commonly encountered during our sediment monitoring, and can be found in soft muddy bottoms from 0-500 meters (although Puget Sound depths reach only about 300 meters).

Cute as a (belly) button

While the different moon snail species look and act similarly, there is one thing that sets them apart –their “belly buttons”. This special belly button is called an umbilicus, and it is formed because of the way a snail shell grows around a central axis (columella). This growth results in a hollow tube running through the center of the shell, forming the belly button-like hole. In some species of moon snails, the hole is filled in with calcium as the animal grows, but in others, the umbilicus is never filled in – so this trait of having an “outy” or an “inny” can set them apart.

The three moon snails we commonly encounter in Puget Sound can be easily identified by the umbilicus.
LEFT: Lewis’ Moon Snail, Nevertina lewisii, has a deep umbilicus.
MIDDLE: The Pale Moon Snail, Euspira pallida, has a partially covered umbilicus.
RIGHT: The Arctic Moon Snail, Cryptonatica affinis, has a completely covered umbilicus.

Get your foot in the door

Lewis’ Moon Snail with its inflated fleshy foot
engulfing almost the entire outer shell.
Courtesy of Kevin Lee, www.diverkevin.com

Like most marine snails, the moon snail has a muscular foot that is used not only to glide on the sediment but also to plow below the sediment’s surface. However, the moon snail’s fleshy foot can do something that most snail feet can’t – it can fill with water and expand to a ridiculous size, practically covering the large bulbous shell.

Believe it or not, moon snails can live to be up to 15 years old, and they don’t survive that long on luck alone. When a moon snail senses danger or is disturbed, it withdraws its inflated foot inside its shell, sealing the opening (aperture) of the shell with a hardened door (called an operculum) so that the soft fleshy foot is fully protected. Meaning “little lid” in Latin, the operculum is present in almost all snails. Animals that would love to munch on a moon snail include octopuses, rock crabs, sea gulls, and even other moon snails.

An upside-down Lewis’ Moon Snail with a clam in its
huge foot. Courtesy of Linda Schroeder - PNW Shell club

The dark side of the moon (snail)

While the unassuming moon snail appears super cute and squishy, it is actually a voracious predator, using stealthy tactics to consume its favorite food: clams. It all begins when the moon snail smells its prey and uses its huge slimy foot to engulf its victim. Once the moon snail gets the unsuspecting clam in its grip, the radula goes to work. Almost all snails have a toothed structure called a radula which they use to consume smaller animal pieces or to scrape algae off rocks.

However, in the moon snail’s case, the sharp-toothed radula is used as a drill to bore holes into the hard shells of clams.

This hole drilled on the top of a clam’s shell is the sign of a
moon snail attack. Courtesy of Central Coast Biodiversity

This is an extremely slow process, with the average moon snail takedown lasting 4 days as it drills ½ mm per day. In order to speed things up a bit, the moon snail produces hydrochloric acid and other enzymes to help dissolve the shell and liquefy the clam’s insides.

Once a perfectly rounded hole is made in the shell, the moon snail inserts its tubular, straw-like mouth and slurps up the “clam smoothie” inside. It can take another day or so for the moon snail to ingest the clam innards. Talk about delayed gratification!

Hot under the collar 

An egg-filled sand collar left on the beach by a moon snail.
Courtesy of Linda Schroeder - PNW Shell club

Female moon snails lay their eggs in a pretty unique fashion. The female covers her entire foot in a thick layer of sand grains that she cements together with mucous. She lays millions of tiny eggs on top of the sand grains, and sandwiches them between another layer of sand. She then detaches herself from the hardened sand-egg mixture and leaves behind a molded sand sculpture in the shape of a shirt collar.

A few weeks go by and the eggs hatch, breaking through the disintegrating collar and swimming away to repeat the process all over again.

By: Dany Burgess & Angela Eagleston, Environmental Assessment Program

Critter of the Month

Our benthic taxonomists love getting to know the crazy
critters at the bottom of Puget Sound.

Our benthic taxonomists, Dany and Angela, are scientists who identify and count the benthic (sediment-dwelling) organisms in our samples as part of our Marine Sediment Monitoring Program. We are tracking the numbers and types of species we see in order to understand the health of Puget Sound and to detect any changes over time.

Dany and Angela share their discoveries by bringing us a Benthic Critter of the Month. These posts will give you a peek into the life of Puget Sound’s least-known inhabitants. We’ll share details on identification, habitat, life history, and the role each critter plays in the sediment community. Can't get enough benthos? See photos from our Eyes Under Puget Sound collection on Flickr.

Eyes Under Puget Sound: The voucher sheet project

The first page of a voucher sheet
for Lucinoma annulata.

This month, we’re taking a break from our regularly scheduled Critter post to tell you about an exciting venture we’ve been working on here in the benthic lab: the voucher sheet project.

Name-dropping

Since 1989, our Marine Sediment Monitoring team has collected over 1,200 different types of sediment-dwelling invertebrates (also known as the benthos) from Puget Sound. As the team’s taxonomists, it is our job to put a name to each little face! We use several methods to be sure we have the names right, one of which is referencing voucher sheets. A voucher sheet is a short document that contains descriptions and photos of each species.

Sort it out

LEFT: A jar of marine worms gets emptied into a dish to
await identification. MIDDLE: In the process of morphotyping.
RIGHT: The completed sample, identified and labeled by species.

It all starts when we sit down at our microscopes and open up jars containing hundreds of tiny preserved animals from our monitoring work in Puget Sound. Each jar gets dumped into a dish, and the animals are “morphotyped” – sorted into piles of similar-looking species based on their physical characteristics. Some species are distinct, and we recognize them right away. Others require delving into books, journals, online references and any other bits of information we can find in order to unravel the mystery of their identities.

A completed voucher sheet for the ostracod Euphilomedes carcharodonta.

 

Detective work

Searching for taxonomic literature takes a LOT of time, and many references don’t contain illustrations. We’ve set out to help solve this problem by creating a set of Ecology publications called Benthic Invertebrate Voucher Sheets. It’s a large undertaking – we’ve completed 50 and have many more in the works!

A close-up of the feet of the marine worm
Cheilonereis cyclurus shows the tiny hairs
and other features that make it distinct.

What's in a voucher sheet, exactly?

After we do our review of the literature, we create a voucher sheet that includes a basic classification, a general description and most importantly, a list of diagnostic characteristics which set that species apart from other similar-looking species. Using cameras attached to our microscopes, we take photographs of these diagnostic characteristics, even features as teeny as the hairs on a worm’s foot! These high-quality images illustrate exactly what to look for when we examine a specimen.

Benefits for Puget Sound and beyond

By generating accurate data on what species are present in our samples, we can detect changes in the benthos over time as they respond to environmental stressors like those associated with climate change and pollution.

Dany uses a microscope and attached camera to
take a photo of a marine worm in the family Ampharetidae.

Voucher sheets not only help us correctly identify the critters we monitor, but they will also help other scientists doing similar work. Most species we collect aren’t limited to our region - many can be found all the way from Alaska to Mexico.

Scientists working in other regions can access our voucher sheets to help them correctly identify the invertebrates they collect. This is one way to improve taxonomic standardization – that is, making sure animals are identified the same way by taxonomists working in different areas – and expand the body of knowledge about our valuable biological resources.

By: Dany Burgess & Angela Eagleston, Environmental Assessment Program

Critter of the Month

Our benthic taxonomists, Dany and Angela, are scientists who identify and count the benthic (sediment-dwelling) organisms in our samples as part of our Marine Sediment Monitoring Program. We are tracking the numbers and types of species we see in order to understand the health of Puget Sound and to detect any changes over time.

Dany and Angela share their discoveries by bringing us a benthic Critter of the Month. These posts will give you a peek into the life of Puget Sound’s least-known inhabitants. We’ll share details on identification, habitat, life history, and the role each critter plays in the sediment community. Can't get enough benthos? See photos from our Eyes Under Puget Sound collection on Flickr.

Eyes Under Puget Sound: Critter of the Month – The Frost-Spot Corambe

Winter is coming! With the impending chilly season upon us, we thought it would be fitting to introduce a frosty-looking fellow as this Critter of the Month: the Frost-Spot Corambe.

Corambe pacifica on a microscope slide. Photo courtesy of Gary McDonald.

Corambe pacifica is a beautiful beast with frosty white speckles that seem to glow as if it just swallowed a set of twinkly lights.

Sink or swim

Click to enlarge image.

The Frost-Spot Corambe belongs to a group molluscs called nudibranchs (pronounced NEW-dih-branks, meaning naked lungs or gills), also known as sea slugs. Like most nudibranchs, C. pacifica begins its life with a coiled snail-like shell in a swimming larval stage. The shell is then shed as the larval nudibranch grows into its adult form.

Keeping up appearances

Feathery gills are visible beneath the mantle,
and the foot can easily be seen with its distinct white rim.
Photo courtesy of Gary McDonald.

Frost-Spot adults grow to a small 10 mm in length and have a flat disc-like body. They have a wide fleshy skirt called a mantle with a notch in the middle posterior (rear) end. Feathery gills used for breathing protrude from under the notch. The gills are a series of simple finger-like plumes which range in number (6-14) depending on the animal’s age.

LEFT: An exposed rhinophore. RIGHT: A rhinophore
partially covered by the protective sheath.
Photos courtesy of Gary McDonald.

Almost all molluscs (with the exception of octopus/squids) have a flat muscular organ called a foot that is used for crawling. The Frost-Spot Corambe’s foot is narrow and translucent with a white line running around the outer edge.

Sitting on top of the animal’s head are two rhinophores, similar to an insect’s antennae. The Frost-Spot has grooved rhinophores that function as sensory organs to detect food, and can retract inside a trumpet-shaped sheath for protection from nibbling predators.

Hide and seek

The Frost-Spot, a master of camouflage, has markings that are designed to perfectly match its habitat, making it almost invisible to potential predators.

Can you spot Corambe pacifica hiding in its habitat on the bryozoan colony Membranipora?
Photo courtesy of Gary McDonald.

In  this case, the habitat being mimicked is Membranipora, a particular bryozoan on which it feeds exclusively. Bryozoans are colonial animals that grow on hard surfaces. Each bryozoan colony is made up of many little “chambers”, each containing an individual animal that makes a tasty snack for the sea slug to slurp up.

The Frost Spot is moderately common in Puget Sound, but it is not often collected during sediment monitoring because of the location of its preferred habitat. Membranipora is found encrusting kelp blades, seagrasses and other hard surfaces that we don’t often encounter with our sampling equipment.

Corambe pacifica deposits its eggs in a spiral shape.
Photo courtesy of Gary McDonald.

Eggs over easy

If you can’t spot the slug itself, you might be able to spot its bright white egg mass. The Frost-Spot Corambe lays its eggs on the bryozoan in a spiral ribbon that looks like a cinnamon roll.

Why the spiral shape, you ask? The spiral gives the eggs a better shot at survival by keeping them close together, but still with plenty of space for oxygen to move between them.

By: Dany Burgess & Angela Eagleston, Environmental Assessment Program

Critter of the Month

Corambe pacifica in its environment. Photos courtesy of Gary McDonald.

Our benthic taxonomists, Dany and Angela, are scientists who identify and count the benthic (sediment-dwelling) organisms in our samples as part of our Marine Sediment Monitoring Program. We are tracking the numbers and types of species we see in order to understand the health of Puget Sound and to detect any changes over time.

Dany and Angela share their discoveries by bringing us a Benthic Critter of the Month. These posts will give you a peek into the life of Puget Sound’s least-known inhabitants. We’ll share details on identification, habitat, life history, and the role each critter plays in the sediment community. Can't get enough benthos? See photos from our Eyes Under Puget Sound collection on Flickr.

Eyes Under Puget Sound: Critter of the Month – The Pea Crabs

Eat your peas

Imagine yourself in a nice restaurant with a delicious-looking batch of steamed oysters in front of you. You insert your knife, pop open the shell, and right before you devour your prize, you discover that your oyster has a tiny crab as a houseguest!

Male Fabia subquadrata, a species of pea crab found in Puget Sound

These little stowaways are called pea crabs, so named because many of them are small (most are less than a cm wide) and round. In the southeastern US, pea crabs are a common sight inside oysters, even considered by some to be a delicacy. This is a sight you won’t often see on the west coast, although plenty of pea crabs are found here. Scientists hypothesize that cold water temperatures or the way shellfish are grown on the west coast might play a role in controlling the number of oysters inhabited by crabs.

Hostess with the mostest

Pinnixa schmitti, the most common Puget Sound pea crab

The pea crabs of the Pacific Northwest have a wide range of hosts – each species has one (or several) favorite organisms that it prefers to shack up with, and they aren’t just bivalves. Mating pairs of Pinnixa tubicola, for example, are often found in the tubes of certain species of polychaetes (marine segmented worms).

The most common Puget Sound pea crab, Pinnixa schmitti, likes to hang out in the burrows of ghost shrimp and echiurans (spoon worms), where it feeds on detritus and leftovers from its host. Many pea crabs can also filter feed if needed, but why pass up a free meal?

Two (or more) peas in a pod

Scleroplax granulata, another Puget Sound species, also chooses ghost shrimp as one of its hosts. Up to six crabs can squeeze into a single ghost shrimp burrow but the crab usually prefers just its host as a roommate. It can also move from burrow to burrow if it finds that the accommodations are better elsewhere. S. granulata may play host to its own freeloading organism as well - a bryozoan (tiny colonial invertebrate) that grows on its shell or lives inside its gill cavity.

Wearing out your welcome

These types of relationships are symbiotic, or an association between two organisms. In the case of pea crabs, many of them are not well understood. In most cases, the symbiosis seems to be commensal; that is, one animal (the crab) benefits from the shelter and food provided by its host, and the host is not affected one way or another by the crab’s tenancy.

Fabia subquadrata inside the mussel Mytilus sp.
Photo courtesy of Aaron Baldwin,
Alaska Department of Fish and Game

In some cases, however, it appears that pea crabs do have a harmful effect on their hosts in a form of unintentional parasitism. Fabia subquadrata, the grooved mussel crab, lives the majority of its life inside a mussel or other bivalve, only leaving its host to find a mate. The female then re-enters the host and produces an egg mass that is almost the size of her body.

Over time, the presence of this sharp-clawed foreign object is thought to erode the gills of the mussel. Eventually the crab larvae will hatch out, each finding a mussel of its own to squat in.

Rule of thumb

The chelipeds of Pinnixa schmitti (left) and P. occidentalis (right)
 have a different shape that helps taxonomists distinguish the two species.

Identifying pea crabs can be tricky because they are so small, and they often don’t have a lot of distinct features to examine. Some of the more reliable characters that taxonomists use to determine the species are the shape of the carapace (shell), the size of the walking legs, and the shape and dentition of the chelipeds (claws).

For example, Pinnixa schmitti has a cheliped with a straight fixed “finger” while the similar-looking P. occidentalis has a finger that is deflexed in a sort of permanent “thumbs down.”

P. schmitti male (top) and female (bottom).
Arrows indicate the abdomen, which can be used to
differentiate between the sexes.

Peas and love

Telling male and female crabs apart may seem like an impossible task when they are so tiny, but there is an easy trick that applies to many crab species. If you turn a crab over and look at the bottom side, you will see where its abdomen wraps around under its carapace. The female crab has a wide, rounded abdomen, because she uses it to carry her egg mass. Males have a much narrower abdomen.

Critter of the Month

Our benthic taxonomists, Dany and Angela, share their discoveries by bringing us a Benthic Critter of the Month. Dany and Angela are scientists who work for the Marine Sediment Monitoring Program. These posts will give you a peek into the life of Puget Sound’s least-known inhabitants.

In each issue we will highlight one of the Sound’s many fascinating invertebrates. We’ll share details on identification, habitat, life history, and the role this critter plays in the sediment community. Can't get enough benthos? See photos from our Eyes Under Puget Sound collection on Flickr. Look for the Critter of the Month on our blog.

By: Dany Burgess & Angela Eagleston, Environmental Assessment Program

Pollution solution: Keep a clean beach, help keep shellfish harvests open

There’s poop on Washington beaches. Bird poop. Fish poop. Insect poop. Dog poop. Cat poop. And yes, there is people poop, too.

North Beach has suffered several shellfish harvest closures due to dangerously-high levels of fecal bacteria.

Beach poop comes in all shapes and sizes, but the vast majority is invisible. Beach poop can originate from many different sources, both human and animal. But whether it comes from humans, our pets and horses, or wildlife it adds fecal coliform bacteria to our beaches and shellfish beds. This directly affects our ability to harvest and enjoy razor clams.

Beach poop is everyone’s business. 

New beach study pinpoints sources

A new study released by our Environmental Assessment Program identifies levels of contamination and main sources of fecal coliform bacteria pollution along the Pacific coast--from Ocean Shores to the Moclips River--and offers solutions that residents and visitors can use to keep beaches safe from this problem. High levels of fecal coliform bacteria not only impact shellfish beds, but can make people and pets sick from exposure to contaminated water.

The North Beach Bacteria Study is a collaboration between Ecology, Washington Department of Health, the Quinault Indian Nation and local governments. Its aim is to improve downgraded shellfish areas and protect those that currently meet water quality standards.

“Maintaining healthy beaches and shellfish beds is everyone’s business,” says Lydia Wagner, our project coordinator on the study. “Beachgoers must be responsible for their own activities that contribute to bacteria pollution.”

The North Beach area receives tens of thousands of visitors during the summer months and clam digs, which creates an intermittent, heavy-use impact on beaches.

Do your part to keep the beach clean

For beach tourists, the study offers three easy tips they can use to keep Washington beaches clean and limit bacteria problems in shellfish areas:

1. Bag your pet waste and properly dispose of it
2. Pack out your picnic trash
3. Don’t feed wildlife

Learn more tips to be a good beach steward on our website. 

Local residents are also encouraged to maintain their home’s septic system. Regular maintenance supports clean beaches and helps avoid costly repairs later.

Dig deeper into the science

The study is the first step in creating a great resource for those interested in protecting Washington’s coastal beaches. Residents will understand how a damaged septic system can harm the beaches they love. Visitors will understand why packing out the beach poop, whether it’s actual poop or common litter, is important to maintaining the safe and healthy beaches they love to visit. 

There is a simple solution to the problem of common beach pollution: bag it up and pack it out.

By: Dave Bennett, communications manager

Eyes Under Puget Sound: Critter of the Month - The Glistenworm

Riddle me this

What is worm-shaped but not a worm, covered in “fur” but not a mammal, and belongs to a group of animals known for having shells, but has no shell?

A photo of the whole animal, Chaetoderma argenteum.

The answer to this riddle is the Glistenworm, a beautiful little creature with a complicated past.

Mistaken identity

If you couldn’t solve the puzzle above, you’re in good company – when they were first discovered in 1844, glistenworms had even the experts stumped! Originally they were thought to be sea cucumbers, and were classified in the phylum Echinodermata. It wasn’t until many years later that they were moved to the phylum Mollusca, which includes clams and snails, and put into their own group – the Aplacophora.

There are over 55,000 species of molluscs in the world but only about 390 species make up the small and understudied aplacophoran group. Of these, only one species, Chaetoderma argenteum, has been properly documented to exist in Puget Sound.

No shirt, no shells, no problem!

TOP: Clusters of spicules
from C. argenteum
BOTTOM: A few individual
spicules from C. argenteum have a
characteristically 'bent' appearance

Typical molluscs create outer shells by secreting minerals from their mantle, a fleshy tissue that surrounds the body and lines the inner surface of the shell. Even some molluscs that appear shell-less, like slugs and squids, have varying degrees of hard structures inside their bodies – reduced or “vestigial” shells that no longer serve much of a function.

Aplacophorans, however, do things differently than their fellow mollusc brethren. Cylindrical and worm-like, they don’t come with a pretty shell that one might find washed ashore on Puget Sound’s rocky coastline, or even an internal shell remnant.

In fact, they are so completely shell-less that they are often referred to as the Naked Molluscs. Instead, they have an outer cuticle embedded with thousands of tiny spines, or spicules, which give them a brilliant shine. This fuzzy-looking exterior layer is practical as well as pretty, presumably making them less palatable to predators.

Getting off on the wrong foot

Many molluscs use a muscular foot for locomotion, and while some aplacophorans do creep around on a simplified, vestigial foot, others have no foot at all. Fortunately, they don’t need to go far. Aplacophorans are exclusively marine bottom-dwellers and spend their time feeding on small organisms in and around the sediment. (Some can even act as parasites on hydroids and corals.) C. argenteum, an example of the footless variety, burrows into the sediment by digging with the shield around its mouth.

LEFT: The mouth of C. argenteum is surrounded by a cuticular oral shield used for burrowing.
RIGHT: The posterior end has a single hole used for both reproduction and excretory purposes.

Who’s who?

Taxonomists worldwide have developed several unique methods to help identify these faceless creatures. One method is to examine the ridges and color patterns of the spicules. To do this, we scrape some spicules from a particular part of the animal’s body and examine them under a light microscope with polarizers. Under the polarizers, the spicules produce bands of rainbow colors, which are compared to charts relating to differing species of aplacophorans.

LEFT: The chitinous radula of C. argenteum
RIGHT: Close-up of sickle-shaped radular denticles

Another identification method is to dissect and examine the radula (a tooth-like feeding structure that many molluscs possess). We start by cutting off a piece of tissue from the animal’s head closest to its oral shield and mounting it on a slide with some bleach solution. The bleach dissolves the soft tissues and leaves the chitinous structure of the radula intact.

We then use a compound microscope to compare the tiny radula to pictures found in the literature to determine the species identification. Parts of the radula are especially scrutinized including the radular denticles and the radular cone.

By: Dany Burgess & Angela Eagleston, Environmental Assessment Program

Critter of the Month

Our benthic taxonomists, Dany and Angela, share their discoveries by bringing us a Benthic Critter of the Month. Dany and Angela are scientists who work for the Marine Sediment Monitoring Program. These posts will give you a peek into the life of Puget Sound’s least-known inhabitants.

In each issue we will highlight one of the Sound’s many fascinating invertebrates. We’ll share details on identification, habitat, life history, and the role this critter plays in the sediment community.

Can't get enough benthos? See photos from our Eyes Under Puget Sound collection on Flickr. Look for the Critter of the Month on our blog.

Eyes Under Puget Sound: Critter of the Month – The Pacific Stinkworm

Making a stink

Compared to most of the tiny mud-dwelling invertebrates in Puget Sound, this month’s critter, the Pacific Stinkworm, is a giant - and it has a gigantic stench to match.

Vampire-free zone

Travisia pupa may look unassuming, but like other species of marine segmented worms in its genus, it has a hidden talent that will knock your socks off. When disturbed, the Stinkworm, as its name suggests, gives off a pungent odor similar to rotting garlic. Our scientists recently witnessed this firsthand while sampling the sediments in Admiralty Inlet. We immediately knew we had scooped up a Stinkworm because of the terrible stink it emitted as the benthic grab landed on the deck of the boat. It certainly does the trick as a human (or vampire) repellent!

Although this pungent phenomenon is not well-studied, it is generally thought to be a chemical defense mechanism used to deter predators. There has also been speculation by scientists that the smell is a byproduct of microbial fermentation in the gut of Travisia – that is, the worms use symbiotic bacteria in their digestive systems to help obtain nutrients from their food.

A great face for radio

Travisia pupa is conspicuous on muddy ocean bottoms from Alaska to Mexico, growing to the whopping size of 8 cm long (a little over 3 inches) and 3 cm wide. With its fat, grub-like body and covering of wart-like vesicles, it’s not likely to win any beauty contests, but we think it might qualify for Miss Congeniality.

Close-up of the underside of the head, showing the mouth.

In addition to the unflattering moniker “Stinkworm,” T. pupa is also referred to as the Pupa Utility Worm, which says a bit more about its admirable qualities. “Pupa” potentially comes from the strong resemblance to the stage in a butterfly’s life when it is undergoing metamorphosis. “Utility” refers to its beneficial role as a bioturbator, performing the important ecological function of turning over and aerating the sediment. T. pupa accomplishes all of this while deposit feeding – burrowing through the sediment, ingesting mud and food particles alike.

Warts and all

LEFT: Live specimen of Travisia pupa, ventral (bottom) view;
Photo by the BIO Photography Group, Biodiversity Institute of Ontario,
courtesy of CreativeCommons
(license: http://creativecommons.org/licenses/by-nc-sa/3.0/).
RIGHT: Close-up of the body, showing branchiae and vesicles.

Puget Sound is actually home to four species of Travisia, but picking out T. pupa is a snap thanks to its vesicles, small fluid-filled sacs which occur in several different sizes along its body. The three other species that occur in Puget Sound have smaller vesicles that are all the same size. All four species have branchiae (breathing structures or gills) along the length of their bodies; in life these are bright red.

By: Dany Burgess & Angela Eagleston, Environmental Assessment Program

Dany gets up close
and personal with a
Stinkworm under the
dissecting microscope.

Our benthic taxonomists, Dany and Angela, share their discoveries by bringing us a Benthic Critter of the Month. Dany and Angela are scientists who work for the Marine Sediment Monitoring Program. These posts will give you a peek into the life of Puget Sound’s least-known inhabitants.

In each issue we will highlight one of the Sound’s many fascinating invertebrates. We’ll share details on identification, habitat, life history, and the role this critter plays in the sediment community. Can't get enough benthos? See photos from our Eyes Under Puget Sound collection on Flickr. Look for the Critter of the Month on our blog.