BIOL 326: Experimental biology of invertebrates

Vancouver Island is a special place with access to some wildlife we city-folk rarely get the chance to experience. At the Bamfield Marine Sciences Centre, visitors and researchers study some incredible biology. From tiny single cellular phytoplankton to entire communities like the intertidal zone (in the photo below!) there is so much to explore.

“Scientists study life’s diversity in order to understand common principles underlying the biology of all species, to understand how our ecosystems came to be and how they function, and to learn how to act sustainably.”

– Beaty Biodiversity Museum

The intertidal zone is so diverse because of its relationship with the tides. With daily, even hourly, changes in water level, so many critters get hung out to dry! Most intertidal organisms have evolved some method for conserving water while the tide is out. Other species prefer living between air and ocean, like Rockweed, which needs to live in the upper intertidal to prevent rotting underwater. Each zone in the intertidal (upper, middle, and lower) is home to different species that prefer the amount of air and light exposure they receive. We can see a zonation pattern very clearly in the healthy ecosystem at Bamfield! Biodiversity is a useful indicator of ecosystem health because each species has a different niche to fill.

Some researchers at Bamfield attach weights to ropes to allow marine invertebrates to grow on them, like in the photo above. These squishy anemones, tube worms, and bright red tunicates are subtidal species. We can find them more easily with this method than out in the intertidal zone because they establish themselves in areas with no air exposure (unless some pesky students come by to check them out).

Exploring the intertidal takes some time and focus. Once you know what to look for, every square metre is suddenly teeming with life. Grab a field guide, check the tides, and get out there!

To explore more incredible examples of biodiversity, check out the Beaty Biodiversity Museum on UBC’s campus! Beaty also provides incredible online resources, including this virtual exploration of the current special seaweed art exhibition.

Alright, is everyone ready for a hot take? Plankton are the most important organisms in the ocean. There, I said it. They form the backbone of almost the entire marine food web (with a few exceptions like macroalgae and bacteria around hydrothermal vents), meaning a lot of marine animals either eat plankton or eat something else that ate plankton. To be honest though, I cheated a little by just saying “plankton,” because plankton are a super diverse group! Did you know the term “plankton” doesn’t even refer to a group of related species? To be a plankton, you just need to be unable to swim against the current. That means that even something as large as a jellyfish counts! Plankton come in all sorts of shapes and sizes, from worms to bacteria to fish!

Recently, our class took a trip out to the Bamfield Marine Sciences Centre, on the west coast of Vancouver Island on the land of the Huu-ay-aht first nation. Bamfield is an amazing hot bed of diversity for marine life, and I want to show you some of the cool plankton we saw while we were there!

These pointy plankton are crab larvae called zoea, which are the first stage of a crab’s life after hatching from an egg. Would you have guessed these critters will become crabs? Another thing to note about zoeae is their implication on what it means to be a “plankton.” These zoeae eventually become crabs, which definitely aren’t plankton, meaning something can start out as a plankton and then end up as something else!

Want to guess what this next plankton is? It’s not a weird-looking worm! What you’re seeing is the medusa form of a hydrozoan! Hydrozoans are related to jellyfish and these medusae are very similar looking. Check out the second picture where I’ve outlined its body so you can make it out better. It has four arms which I’ve pointed to, and the worm-looking thing is its gut.

Last is this little worm, and it really is a worm this time (probably)! This one is interesting because I’m not 100% sure what it is. In discussion with one of my professors, we think it is a kind of worm called a Sipunculid, but sometimes you just can’t know without a lot of time and effort, and sadly we didn’t have the time at Bamfield. Whatever it is, it’s super interesting, so I just had to share it!

I hope you have a greater appreciation of plankton now! If you want to learn more, check out this video from BBC Earth which validates my hot take (which is maybe not that hot if BBC is talking about it?) and if you want to see some beautiful microscope videos of another plankton, watch this video on copepods!

If I could carry around a bag with a collection of sea creatures to show everyone I meet, I totally would (wouldn’t you?). A few weekends ago, my classmates and I visited Bamfield Marine Sciences Center, located on the west side of Vancouver Island. We had the opportunity to learn about marine life by collecting plankton, exploring beaches, and examining all the animals in their education lab. In my hypothetical ocean bag, I would have filled it with all my favourite sea creatures I saw at Bamfield and called it my Bamfield Bag^TM.

So here today, I will show you what I would have in my Bamfield Bag^TM     

First up, anemones!

These squishy creatures have numerous sticky tentacles that actually sting you when you touch them! But don’t worry because our skin is too tough to feel anything. Some of these green anemones have algae living inside them that provide the anemone with nutrients. Fun fact: the hole in the middle is their mouth and also their rear end, and at Bamfield, I heard some people using the term “manus” referring to their mouth/butt.     

The next thing in my bag is sea stars!

We saw many types of sea stars including the blood star, bat star, vermillion star, and a leather star that actually somewhat smells like garlic. Sea stars have an interesting way of eating, in which they essentially throw up their stomach onto their prey, digest their food outside their body, and slurp everything back in. Talk about table manners!

1. itty bitty blood stars | 2. a vermillion star | 3. bat star | 4. leather star (taken in Stanley Park) | Photo 3 taken by Sarah Hsu, all other photos by me

Sea Cucumbers!

I’ve always thought sea cucumbers should be called sea pickles because they live in saltwater, but the general consensus seems to be sea cucumbers. Either way, I don’t plan on snacking on them anytime soon, but they are considered a delicacy in some cultures in East and Southeast Asia.

Sea cucumbers are cool (as a cucumber) and they breathe through their butts. Also they are super squishy and fun to hold, which is the main reason why I would have them in my bag.

Nudibranchs!

These are the cool cousins of drab, dreary land slugs, sometimes with fluffy gills on their back. These whimsical slugs lay their eggs in a pretty spiral or rose-like pattern (shown below).    

Quick interlude from the invertebrates: Sea sacs!

This seaweed is also known as dead man’s fingers, or Halosaccion if you’re a seaweed nerd. They are filled with seawater and have pores on the end – they prove to be handy in squirting your friends! The ones I found at Bamfield were tiny (around the size of a dime), but they were still successful in spraying people!

Back to the invertebrates: Urchins! 

These spiny critters are close relatives of sea stars, sea cucumbers, and sand dollars. They have five teeth that chomp on algae, and their intricate mouth is called an Aristotle’s lantern! 

1. A purple urchin hanging out in a tide pool at Bamfield (photo by me) | 2. An urchin’s Aristotle’s lantern. Photo from The Echinoblog

Last but not least, my personal favourite, chitons! 

I like to think of chitons as if you took the inside of a snail and stuck it in a mini armadillo shell. To scrape algae off rocks, they use something called a radula, which is basically a tongue with lots of tiny teeth on it (quite horrific, I know).  

Want to decide what to put into your own Bamfield Bag^TM? Check out this video from Bamfield to see all the amazing animals you can find there!

The Oscars have come and gone, and so has Bio 326’s trip to the Bamfield Marine Sciences Centre. Both, surprisingly, involved worms.

In Bamfield we used a mesh tube to strain zooplankton (animals that can’t fight against currents) out of the ocean. When using microscopes to review our collection, we couldn’t stop watching a fearsome arrow worm thrash its jaws – just like the Oscar-worthy giant sandworms in Dune!

But while worms are represented in Sci-Fi Thrillers, what other plankton have movie-star potential? Keep an eye out for these totally-real upcoming flicks:

Splashdown, a copepod sports drama

It’s the Burrard water polo team’s first finals, and they’re losing hard. The Sargasso Sea Dragons are too quick! When Burrard’s MVP Olly Ostracod loses an antennae in a skirmish, the coach puts the rookie Cally, a twitchy copepod, into the arena. Cally rushes for the ball, long antennae deflecting competitors, and uses her strong oar-like appendages to speed to the goal. Will her fast moves and jumping power propel Burrard to victory? Or will her lack of heart (literally – most copepods don’t have hearts) get her kicked off the team? 

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Surreal Fans, a barnacle coming-of-age story

Cypris Hennings just moved from small-town Hanson Island to Vancouver, and his senior year of high school couldn’t get worse. His girlfriend dumped him over text, he didn’t make the swim team, and his body just changed from a hot Nauplius to a blobby… thing. His parents pressure him to cement to a rock, but he just wants to play in his synthpop band EvoDevo. As a barnacle larvae, he’s incapable of eating; energy stores dwindling, does he stay true to his family or his dreams? 

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No Fishing Trades, an amphipod business drama

All the big-shot stock traders work in Wall Stream, and Mala Costrata is no exception. But though her net worth is in the krillions, the stream of clients to her algal investing company has dried up. Suspiciously, a similar company run by the Caprellid Brothers is gaining popularity. To make it out on top she must diversify beyond brown algae, causing a food web catastrophe. 

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Lance Back, a crab larva historical comedy

The Medieval Times: lords, ladies, and… seahorse jousting? Zoro Zoea’s long dorsal spine isn’t just to deter predators – here, it’s perfect for flinging off opposing riders. But Eucer, the village’s new porcelain crab larva, has spines that make Zoro’s look more than microscopic. The larvae attract loyal planktonic followings, and things spiral out of hand fast; culminating in a full on Cretaceous Crab Revolution.

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Admittedly, these films won’t make it past Indie festivals. But while their plots may be Hollywood fiction, these creatures are truly part of the charismatic microscopic cast found throughout the world’s oceans!

 
For some algal-based theatrics, check out the planktonic inspiration for Hitchcock’s The Birds!

If you’re interested in amazing marine life, then look no further! British Columbia, Canada is home to some spectacular wildlife and beautiful scenery. The west coast of Vancouver Island is no exception to this, and in fact may be the most animal dense and beautiful marine locations of them all! Exposed to the powerful, deep blue, Pacific Ocean, the west coast of Vancouver Island gets a suite of fascinating animals of all shapes and sizes. Some of the more charismatic ones you may be familiar with include Orca whales, Humpback whales, Sea otters, Salmon, Sea lions, and maybe even sea stars, AKA starfish (Which, in fact, aren’t fish at all!). Notably, almost all these organisms are large and vertebrates (they have back bones= vertebrae) meaning they are more closely related to us humans! But our amazing friend the sea star, is just one of thousands and thousands of small intertidal invertebrates (have no backbone) who you may not know so well. Personally, I think it is these creatures who are the most beautiful and amazing of them all, and I would like to introduce you to them. To showcase their beauty, check out this sea slug! All of the little frills off of its back are its gills, allowing this organism to breathe through its skin!

My class and I took a trip out to the Bamfield Marine Sciences Centre on the west coast of Vancouver Island to see this beauty with our own eyes. If you want to find other creatures as beautiful and colourful as this sea slug, I’d suggest you’d come explore the coastline on Vancouver Island too! It is at the coastline where you will find a very special region of land called the intertidal zone; It is here where you will find a large diversity of invertebrates! The intertidal zones boundaries are created by the moon (and sun) which causes tides and are represented by the highest high tide and the lowest low tide of that year. Because of these tides, the organisms who live here are exposed to both air and water throughout the day. As such, they often have many unique features which allow them to survive. Take these giant green anemones as an example, these guys stick small shells to their bodies so that the sun’s rays do less harm to them during low tides on sunny days!

Or these barnacles with strong plates of armour that not only protect them from predators, but also prevent them from drying out as they seal them shut during low tides on hot days.

To inspire you further to join us in the intertidal along the west coast of Vancouver Island here are some more beautiful sights you could see or invertebrates you could find!

If you can’t join us here there are plenty of other coastlines out there to explore (maybe less diverse and beautiful, but nonetheless, still amazing). And if you can’t do that! The amazing staff at the Bamfield Marine Science Centre has made their own intertidal walkthrough so you can explore this beauty from the comfort of your own home!

On the west coast of Vancouver Island is Bamfield Marine Sciences Center. The former site of the trans-pacific telegraph cable, the facility has been operating as a research and education facility since 1972. 

I first visited Bamfield with my Grade 8 science class in February 2014, where I was blown away by the intertidal and marine diversity that could be found not too far from home. So, I was thrilled to get the opportunity to return to Bamfield 8 years later, for a UBC trip with Biology 326!

Adventures aboard the Alta

To sample the invertebrates found on the ocean floor in Barkley Sound, we set out aboard BMSC’s 43-foot offshore vessel, M/V Alta to perform a dredge. Along the way to our destination, we noticed an animal absent from Vancouver’s waters: a Sea Otter! These marine weasels play an important role in the local ecosystem, by consuming sea urchins. Sea urchins graze heavily on kelp, so by limiting the urchin population, sea otters allow kelp forests to grow, providing habitat for a multitude of other marine species. Sea Otters which were hunted to local extinction in this region, leading to extensive kelp forest loss. However kelp forests have returned following their reintroduction in the 1970s!

Our dredge of the ocean floor revealed a diverse array of marine life. Sea urchins, sea cucumbers, snails, crustaceans, several species of sea stars and much more were all abundant. However, the highlight was undoubtedly a young octopus! These organisms were briefly studied on the boat before being returned to the water.

Incredible Invertebrates

Continuing our exploration of invertebrates in the Bamfield marine ecosystem, we spent time investigating life in the intertidal zone, dock communities, and in the lab.

Intertidal Zonation

Every day, the gravity of the sun and the moon impact our planet, pushing and pulling the water here on Earth. This results in tides! At low tide, the ocean recedes to reveal an incredible array of marine life that is often hidden below the water. While underwater conditions are pretty constant, animals exposed to the air have to be able to survive a wide range of temperatures, light levels, humidities, and other potentially stressful effects. Animals higher up on the beach spend more time exposed to the air, whereas animals lower on the beach spend more time in the water. This results in intertidal zonation, with different organisms visible in different parts of the intertidal zone. At Bamfield, we found lots of Pacific Acorn Barnacles high in the intertidal zone. The mid-intertidal zone had lots of mussels, and tide pools and the low intertidal zone had many beautiful sea stars and sea anemones.

Sea Star Mysteries

While many questions have been answered through research in the intertidal zone, mysteries remain. One of these surrounds the colour of Ochre Sea Stars. In the waters around UBC and Vancouver, these mussel-eating echinoderms are most frequently purple in colour. On the west coast of Vancouver Island, they are most frequently orange. The reason for this change in colour is unknown! Dr. Alyssa Gehman and Dr. Chris Harley of the BIOL 326 teaching team are investigating this, and hypothesize it could have to do with pigments found in mussels, one of their primary foods.

Our field trip to Bamfield was fun and educational, and leaves me eager to return someday soon! To learn more about Bamfield Marine Sciences Center, visit their website: https://bamfieldmsc.com/