Ucluelet Aquarium grand re-opening March 15

by Amanda Kahn

The Ucluelet Aquarium, across Barkley Sound from Bamfield, is re-opening its doors for another summer season on Saturday, March 15 at 12 noon.  The aquarium displays local marine life of the Pacific Northwest with the distinction of being one of the few “catch-and-release” aquaria in the world.  Admission on opening day is by donation.

The aquarium will be open on Saturday from 12 PM until 5 PM, then will begin regular hours of 10 AM to 5 PM until the summer (when they will stay open until 6 PM).  Check their website for current hours and rates.

Touch tanks at the Ucluelet Aquarium

Touch tanks at the Ucluelet Aquarium. Credit: Ucluelet Aquarium Society.

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Morphing Pisasters, Batman!

Amanda loves tide poolsby Amanda Kahn

One day while exploring an island in Trevor Channel during a low tide, I happened across this sea star.

Pisaster

It’s Pisaster ochraceus! And the logo of the Madreporite…almost in the correct pose too… Credit: A Kahn 2012

Apart from looking like it was dancing a happy dance on a barnacle-encrusted rock, there was something notable about this individual.  This species of sea star usually comes in one of three colors: orange, reddish-brown, or purple.  However, this one was orange with purple tips on its arms.

Pisaster arm tip

Credit: A Kahn 2012

The purple tips on the sea star I found made me wonder what causes colors to change in these sea stars. It’s not fully known yet, but people are thinking about it.

Pisaster ochraceus is commonly found in the intertidal zone around Barkley Sound and is known to be a keystone predator for intertidal habitats.  This means the sea stars are largely responsible for the way intertidal communities are arranged, with bands of mussels in the middle intertidal zone and very few mussels and barnacles beneath that zone.

What is known is that color variation is not genetically determined, at least not directly.  A study done partly in Bamfield by Chris Harley and co-authors found no meaningful distinctions between orange versus red versus purple sea stars, even though they looked very different.  Instead, within an area, such as within the San Juan archipelago or the Strait of Georgia, all sea stars had very similar gene sequences, indicating that all color morphs can and do breed freely and easily with other color morphs.  Fitting that idea with the commonly-accepted theory that confines individuals within a “species” (two individuals can’t reproduce to create viable offspring that are also capable of reproduction if they are different species), Harley and co-authors concluded that there don’t seem to be multiple similar-but-not-quite-the-same species, called cryptic species, living amongst each other on the intertidal rocks of Barkley Sound.

Pisasters

Different colors of Pisaster ochraceus coexist along the Bamfield shoreline, but why they are different colors, and what determines what color they grow to be, remains unknown. Credit: Jackson Chu via Flickr

Orange and purple (and sometimes white) color morphs have also been observed in a deep-sea heart urchin, Echinocrepis rostrata.  Urchins are part of the same phylum as sea stars, so they are expected to be similar to each other.  The color morphs of E. rostrata were also not genetically distinct from each other, indicating that the colors do not seem to be cryptic species of each other either.

So if colors are not related to the genetics of the sea stars, then what’s left?  Well, as in the debate of nature vs. nurture, if the sea stars are not born with the genetic predisposition to be purple or orange (the “nature”), then it must be something in their environment that determines their color (the “nurture”).  This is where it gets really interesting, with Harley and co-authors finding that the differences in diet might affect the colors of sea stars (though that was not conclusively tested), while size and location did not.  The authors in the paper even noted,

“Notably, small fractions of orange stars have purple coloration at the tips and along the undersides of their rays, especially if a ray is actively growing (e.g., following injury; CH, pers. obs.). Even smaller fractions have a tracework of purple coloration on their aboral surface (CH, pers. obs.). Very small Pisaster are not chromatically differentiated, and some orange adults may turn purple when held for long periods under laboratory conditions (J. Pearse, Long Marine Laboratory, University of California Santa Cruz, pers. comm.). These observations imply that individuals express different pigments as they grow or age; however, the effects of age and diet remain confounded for the time being.”

The idea that sea stars may change colors depending on changes in their diet or age was a new concept to me.  Why do you think different color morphs happen?  Is it related to diet, like Harley and co-authors suppose?  Or age-related?  Maybe you’ve read a more recent paper about it in a class?  Please let me know in the comments section below–I’d love to learn more about this!

Literature Cited

Harley, C. D. G., M. S. Pankey, J. P. Wares, R. K. Grosberg, and M. J. Wonham (2006).  Color polymorphism and genetic structure in the sea star Pisaster ochraceus.  Biological Bulletin 211(3), 248-262.

Vardaro, M. F. (2010).  Genetic and anatomic relationships among three morphotypes of the echinoid Echinocrepis rostrata. Invertebrate Biology 129(4), 368-375.

Waves, Caves & Humpbacks

By Danielle Ludeman

Living in Bamfield definitely has its perks, one of which is being located in the spectacular Barkley Sound. With hundreds of islands separated by deep water channels, Barkley Sound hosts abundant marine and wildlife along its diverse coastlines, which not only makes it an ideal location for doing research, it also makes for an amazing place to explore during days off! The multitude of islands that occur in Barkley Sound, such as the Broken Group Islands and the Deer Group, have become famous among kayakers and divers alike, and a couple of weeks ago I had the opportunity to see why when I did an overnight kayaking trip to the Ross islets in the Deer Group.

Visiting the seals at Wizard island. Photo credit: D Ludeman

Leaving early in the morning from the Bamfield Marine Sciences Centre to avoid the afternoon westerly winds, we packed the graduate kayak hatches full of camping gear, food, and drinking water and headed out across the Trevor Channel.  With a brief stop at Wizard island to visit some seal friends, we made it to the Ross islets within an hour and a half and set up camp at one of the two camp sites.  Lucky for us, even though it was one of the busiest kayaking times of the year, we arrived just as another group was leaving and so snagged one of the two camping spots on the islet!

Kayaking around Fleming Island in Barkley Sound. Photo credit: D Ludeman

One of the many bald eagles spotted on Fleming Island. Photo credit: D Ludeman

We then had the rest of the day to explore, and taking some advice from the departing kayakers we decided to paddle around Fleming, a large island beside the Ross islets.  Just as we were leaving (enjoying the much lighter kayaks to paddle in!) the clouds broke and it turned into an amazingly sunny day – even though the previous week in July had felt like Fogust!  The calm waters along the Trevor Channel side of Fleming made for some peaceful paddling, and we could even see some sea life through the glass-like waters!  On land, the long sandy beaches were stunning, and it wasn’t hard to spot the many bald eagles on the wind-swept trees!

As we rounded the corner at Tzartus island, we glimpsed this amazing sea cave and just had to go have a look.  Although it was tempting, we decided against paddling through it – probably a good thing too as when we were chatting to our fellow Ross islet campers later that evening, one of them had a story of going for a little impromptu swim right in the middle of the same cave!  Instead, we found a nice little beach to have lunch at, and enjoyed the amazing view that Barkley Sound has to offer.

Sea caves are abundant in Barkley Sound, such as this one on the southwest corner of Tzartus island. Photo credit: D Ludeman

After lunch, we left the calm waters of Trevor Channel behind and took off to paddle the side of Fleming along the Imperial Eagle Channel. The waves, although a little challenging, were exhilarating!  And well worth what we were about to see.  As soon as we turned the corner at the North side of Fleming we heard the explosive snort of a humpback whale and looked just in time before it dove back underwater.  We sat there motionless (or as motionless as we could in the waves) waiting for it to grace us with its presence again, and feeling the rush of being so near such a magnificent creature.  After a few more breaths the whale moved on, and so did we to battle the waves and observe the many more sea caves along Fleming.

The many colors of Pisaster. Photo credit: D Ludeman.

Late afternoon we arrived back at the Ross islets, just in time for the low tide! We gave our arms a much needed break and took off exploring the small island on foot, checking out the many tide pools and awesome creatures that they house! From the colorful starfish Pisaster, to the massive californian mussels Mytilus, and the medieval- looking gooseneck barnacle Pollicipes, there was plenty to seek and discover.  And after cooking some dinner on the beach, we sat down and relaxed, watching the tide come up on the rocks, and the sun set behind the Broken Group Islands.

Sunset at Ross islets. Photo credit: D Ludeman