Marine Biology Archives

I grew up on the Oregon Coast in beautiful Bandon by the Sea. I spent many a day on the shoreline investigating the marine invertebrates under the rock crevices and walking the sandy beaches. My brothers and I longed for the minus tides, providing us the rare opportunity to go spelunking in the sea caves just off shore. These rocky islands are now protected areas for marine bird nesting habitat but back in the 70s, it was our playground.

dune geology tunicates — Dune geology features: foredune and deflation plain

Tracking Marine Debris

In all the years I have spent on the beach, I have found a diverse amount of debris and organisms in varying states of decay. I probably spend an equal amount of time sifting through the wrack on the high tide line as I do in wave zone digging in the sand looking for mole crabs.

I have found marine debris from Japan evidenced by the kanji script. An occasional flip flop or fishing net remnants are not uncommon. While immersing myself in marine biology courses at the Oregon Institute of Marine Biology one summer, I even found several squid egg cases that washed ashore after a winter storm, providing my peers and I an opportunity to observe the development up close. Yet, once in a while, I am still surprised at what washes ashore.

tunicates — Walking along the ATV trail across the deflation plain

This past holiday weekend, my family and I enjoyed a leisurely walk on the beach near our home. Our goal was to field test a new marine debris app, a joint initiative between the NOAA Marine Debris Program and the Southeast Atlantic Marine Debris Initiative. The tracker app allows you to help make a difference by checking in when you find trash on our coastlines and waterways.*

We drove out to the North Spit and thereafter began our excursion through the deflation plain. We soon discovered, however, that there was too much standing water to stick to the trail that meandered through the wetland area. We thus walked along the ATV road until we reached the small foredune. Just a few feet up and over and we arrived on the sandy beach.

No sooner did we arrive at the shore and we immediately were captivated by the presence of a strange organic material that was strewn across the beach for miles. Upon first glance, it looked like a hard plastic tube resembling a sea cucumber. My first suspicion turned out to be incorrect, however. Upon returning home, I learned that what we had found were actually colonial tunicates. Fascinating!

tunicates rare creatures — Planktonic salps, *Pyrosoma atlanticum*, strewn across the beach.

What are Tunicates?

This bizarre and rarely-seen creature is called a pyrosome, a species of pelagic colonial tunicates. Their scientific name, Pyrosoma atlanticum, is derived from the Greek words pyro meaning ‘fire’ and soma meaning ‘body’ which refers to the fact that they are known for bright displays of bioluminescence.

Pyrosoma atlanticum are one of the few pyrosomes that make it to the west coast of the U.S. The species found here are less than a foot but can get as long as 24 inches. Largely colorless, they can show up as pink, grayish or purple-green.

tunicates invertebrates — A specimen of the colonial tunicate, *Pyrosoma atlanticum*

These massive colonies of cloned creatures are related to a kind of jellyfish called a slap. A tunicate is a marine invertebrate animal, a member of the subphylum Tunicata, which is part of the Chordata, a phylum which includes all animals with dorsal nerve cords and notochords.

Each individual organism is about 1 cm long – less than a third of an inch. They are all connected by tissue and in turn form this colony that looks like a plastic tube. The recent winter storms have caused them to strand on the shores and have been found in all areas of the coast.

Usually found in temperate waters as low as 800 meters. The colony of animals is comprised of thousands of individual zooids and moves through the water column by the means of cilia (an organelle found in eukaryotic cells that project from the much larger cell body).

As they move through the water column, sometimes close to the surface and sometimes as far down as 2600 feet, they filter plankton out of the water for food. As it sucks water in, it then pushes it back out, thereby propelling it through the ocean. It does all this via one opening only, so it moves incredibly slow.

For more images of Pyrosoma, check out Bob Perry’s photographs . Included in his work are a few pseudoconchs (false shells) of the pelagic mollusk Corolla which we similarly found.If you are interested in learning more about invertebrates with your students, I encourage you to look into the Amazing Animals curriculum unit I have written to introduce middle level students to zoology. This 10-week unit is full of inquiry-based activities and lesson plans fully outlined for you.

* Due to our fascination with these rare creatures, we didn’t spend as much time with the debris tracking app as I had intended. We’ll give it a go another time.

I love slugs! They are one of my favorite animals, particularly if limiting the scope of the question to invertebrates. In my opinion, they are one of the most beautiful and fascinating organisms.

You’re likely thinking I have lost my mind. “You really think this guy is beautiful?”

Sea Slugs, Snails, and Sea Hares — Pictured here is the banana slug

Yes, I do. Well, actually, in my mind I was picturing his close relative the sea slug or nudibranch. This summer, I have been volunteering at the new Marine Life Center at the Oregon Institute of Marine Biology and I’ve thereby had the opportunity to learn so much about these fascinating animals. Let me introduce you to the gastropods.

Class Gastropoda

The Gastropoda or gastropods class, more commonly known as snails and slugs, are a large taxonomic class within the phylum Mollusca. A very diverse group with 60,000 to 80,000 living species (second only to insects in number of species) that includes snails and slugs of all kinds and all sizes from microscopic to large. There are many thousands of species of sea snails and sea slugs, as well as freshwater snails, freshwater limpets, land snails and land slugs.

Sea Slugs, Snails, and Sea Hares @EvaVarga.net — How many sea slugs can you find in this picture?

The anatomy, behavior, feeding, and reproductive adaptations of gastropods vary significantly from one group to another. The class also inhabits an extraordinary diverse habitats including gardens, woodland, deserts, mountains, rivers and lakes, estuaries, mudflats, the rocky intertidal, the sandy sub-tidal, the abyssal depths of the oceans including the hydrothermal vents, and numerous other ecological niches, including parasitic ones.

Snails & Other Shelled Gastropods

Commonly, snails are those species with a single external shell large enough that the soft parts can withdraw completely into it. Those with a shell into which they cannot withdraw are termed limpets.

The marine shelled species of gastropod include species such as abalone, conches, cowries, periwinkles, whelks, and numerous other sea snails. Each produce seashells that are coiled in the adult stage. In a number of families of species, such as all the various limpets, the shell is coiled only in the larval stage, and is a simple conical structure after that.

Slugs or Gastropods Without External Shells

Those gastropods without a shell, and those with only a very reduced or internal shell, are usually known as slugs. The various families of slugs are not closely related, however, despite a superficial similarity in the overall body form.

Sea Slugs

The phrase “sea slug” is perhaps most often applied to nudibranchs and they come in an outstanding variety of shapes, colors, and sizes. With translucent bodies, they appear in just about every color on the rainbow. Of course, these bright colors are cause for warning to potential predators that they are poisonous with stinging cells. It is their colors that so fascinate me.

Like all gastropods, they have razor-sharp teeth, called radulas. Most have two pairs of tentacles on their head used primarily for sense of smell, with a small eye at the base of each tentacle. Many have feathery structures (ceratia) on the back, often in a contrasting color. These act as gills.

All species of sea slugs have a selected prey, that is specifically fitted for them to hunt. Amongst the diverse prey are jellyfish, bryozoans, sea anemones, sponges, and other various organisms including other sea slugs.

Sea Hares

The sea hares, clade Aplysiomorpha, are often quite large and sometimes described as large sea slugs. They have a small, flat, internal shell composed of proteins. The name derives from their rounded shape and from the two long rhinophores that project upwards from their heads and that somewhat resemble the ears of a hare.

The greatly modified shape of the sea hare and the fact that it orients its body lengthwise along the leaves makes it almost invisible on the sea grass Zostera. An herbivore, it feeds by grazing the film of organisms, mainly diatoms, off sea grass leaves, leaving a characteristic feeding scar on the leaves.

Take it Further

Learn more about Phyla Mollusca in my earlier post, Echinoderms and Molluscs. You might also be interested in my in-depth zoology curriculum specifically designed for middle school students.

My daughter has always loved anything related to arts and handcrafts. Even as a toddler she would spend hours drawing and making gifts for her family with my craft supplies. It is no wonder that art is one of her strongest passions. She has wanted to try 3D art pens for some time and was delighted to learn I would have the opportunity to review the IDO3D for my readers.

As a family, we have been volunteering regularly at the new marine life center and have made several field trips to a variety of coastal habitats to learn more about the local ecology. When the IDO3D art pen arrived, she knew immediately what she wanted to create … jellyfish.

Disclosure: I was compensated for my time reviewing this product and for writing this review.

IDO 3D Art Pens

The IDO3D comes with four pens (or color cartridges): blue, green, red, and yellow. Each pen has a safety seal or cap that will need to be removed. Thereafter you will twist on the cap. Lastly, you snap the blue spotlight holder into place (it clicks into place).

There are instructions on how to use the 3D art pens provided as well as helpful tips and tricks detailed in a short video. I was very impressed with how quickly we got the hang of it. Granted, our lines are a little wobbly and jiggly but as they say in the video, “Practice and patience are the key.”

Creating Jellyfish with 3D Art Pens

Using my invertebrate zoology textbook as a reference for jellyfish anatomy, she was underway within just a few minutes. One of the materials in the box was a plastic sheet shaped like a bowl which she used to begin her project; creating the exumbrella inversely. She chose blue ink for this part – though she also opted not to fill in the connecting space as she wasn’t sure if she would have enough ink.

Once it had cured, she proceeded to create the internal anatomy with green ink: mouth, gastrovascular cavity, gonads, and oral arms. She discovered, however, that the space was too confined for the spotlight and she wasn’t able to add all the parts she would have liked. “I probably would approach it a little differently next time,” she stated. “I think I should have created the internal parts separately and then attached them later.”

Lastly, she began to add the tentacles and worked vertically as she did so. This proved to be the most challenging part of the process. As they were so long and thin, they kept leaning in one direction or another rather than staying vertical. Like any art medium, she recognizes that it takes practice and patience.

“I really like this pen. It is easy to use and I can create something right away. Perhaps the jellyfish was too complicated for my first project.”

Classes & Projects for IDO 3D Art Pens

We look forward to creating a variety of projects with the IDO3D art pen. There are also several 3D Art Classes from which to choose. When my son saw the following video he said,

“You can do all that?! That’s so cool!”

Where to Buy IDO 3D Art Pens

The IDO3D art pen is available from a variety of retailers nationwide. It is also available on Amazon.

For ideas and inspiration for projects, I encourage you to follow IDO3D on Facebook, Pinterest, Twitter, and YouTube.

In July, we spent a few days at the Oregon coast whereby we had an opportunity to explore many of my favorite natural habitats as well as visit the campus of Oregon Institute of Marine Biology where I spent two summers inundating myself in a multitude of graduate courses when I was teaching for North Bend Schools. It was fun to show the kids the classrooms and labs on campus … and as summer classes were in full swing, we were also able to see numerous invertebrates on the water table as well as a live octopus in the holding tank.
We spent a few hours on the docks as well – both in Bandon and in Charleston – doing a little belly science. We were delighted to find numerous sea slugs meandering about – my favorite little invertebrate! While crabbing with dad, we were not successful in catching any Dungeness of legal size or sex, thus we opted to bring home a few we purchased from a local fisherman.
We tried our hand at clamming and fishing as well – but again, we were not successful. Oh well. We are learning. 🙂 We checked up on my dad’s new neighbor – a beaver – and spent a leisurely afternoon letterboxing and agate collecting near the jetty.
Another day, we drove out to Cape Arago to do some tide-pooling. It wasn’t quite the minus tide we’d hoped for but we were not surprised to see two OIMB vans and thereby a class of college students undertaking their own investigations. I was delighted at the variety of organisms we were able to see – when I had taken the kids to the tide pools a couple of years ago, we had opted to go to Sunset Bay and discovered it was significantly more barren due to the easy access and thus more foot traffic by the public. What stood out to me the most were the numerous chitons – mossy, leather, and gumboot chitons were everywhere! More than I recall from the summers when I was an OIMB student.
Buddy most enjoyed catching the small shore crabs – many were quite elusive, perhaps thankfully so as they were larger and their pinch much stronger. 🙂 It was a wonderful morning and their journal entries showed. I will post their sketches when they finish – they have the basic outlines but wanted to add color but haven’t gotten around to it just yet.