Sunday, July 26, 2009

One for the Little Guys

One of the best things about the Ucluelet Aquarium is the opportunity to see and appreciate all the little guys that are often missed among the kerfuffles of the sea. It only seems right that the blog should reflect this and here it is: One for the Little Guys. By taking advantage of our microscope and cameras we were able to show off a few of our most-missed buddies.

Calcareous tubeworms (Serpula columbiana) can grow to be up to 6.5 cm long and have a diameter of 0.6 cm. These tube-secreting worms stay encrusted to the rocks for most of their body length and can hide inside their shell when startled. In the below photographit is possible to see the trumpet- or funnel-shaped operculum that the animal uses to block of the entrance of the tube when fully withdrawninto the shell. The aquarium also has feather duster tube worms that when approached with a finger will rush into their softer, more flexible home.These animals are filter feeders that munch on plankton and reproduce by broadcast spawning.

The Sitka Periwinkle (Littorina sitkana) is commonly found in protected intertidal zones trying to stay moist. They often will aggregate as seastars do in an attempt to not dry out. Living similarly to other snails and as the prey of some nudibranchs, the sitka periwinkle can be variable in colourfrom a light brown to black and will often have stripes have various thickness and colour.

The Heart Crab (Phyllolithodes papillosus) lives between the intertidal zone and down to 183 metres. Its camouflaugecomes from the hard spines covering the legs and pincers. They grow to be 10 centimetres across the carapace but as youcan tell in the picture they are quite small when they are young. These guys get their name from the heart-shaped designon their backs.

Little Skeleton Shrimp have been popping about in several tanks as they develop into a size visible with the naked eye. This generic grouping contains several species which can be either filter feeders or predators. These shrimp tend to be found in large groups in our tanks and can be seen attaching on to the algae or rocks and swaying to and fro.

The excitement level of the small common barnacle (Balanus glandula) is unfortunately often lost on local beachcombers- and What a mistake thatis!! These crustaceans begin life as small larvae that contribute to the plankton population as they are released from the shell of the fertilized adult. Each adult will brood and release up to 13 000 larvae at a time. As they mature they are attracted by settledbarnacles towards rocks, pilings, or even animals on which they are able to settle. Once committed to a surface the barnacle willattach itself for life using cement glands in the antennae. Their appendages change into a fan like structure- the cerripeds- and theyconstruct a permanent shell structure in which they will entirely hide when not feeding. They filter the water using their cerripedsto catch all the plankton that they feed on. The funnest fact of all? When it comes to mating the hermaphroditic barnacle will probetheir neighbours with their male reproductive organ which can be up to five times the size of the rest of the body!!

Get your glasses on and come check these little guys out first hand!

-Mary Vasey, Interpreter

Sunday, July 19, 2009

Love is in the Water

It seems as though true love is blossoming before our eyes as the opposing genders of many species become better acquainted. Events such as: spawning sea stars and sea cucumbers, eggs from Oregon Hairy Tritons and various nudibranchs, and the claws-on mating of the Red Rock Crab are spontaneously occurring at the Ucluelet Aquarium. It is a good idea to breed when the warming water supports more growth as the success rate of young increases.

The predatory Hairy Oregon Triton has begun laying eggs in a beautiful spiral shape on the window of one of our tanks. This animal is suspected to have the longest larval development period of any marine invertebrate- up to four years. They will wait to undergo metamorphosis until there is adequate food to support their growth. The appearance of the eggs indicate that 6 - 9 months earlier a snail couple had intimate relations in which internal fertilization occurred. The snail will now protect these eggs for up to nine weeks from predators before the young larvae hatch. These hairy guys are covered in periostracum which are brownish bristles aiding in camouflage, when fully grown the snail will span up to 6 inches across.

Hairy Oregon Triton laying their eggs in a spiral pattern on the glass tank. [Mary Vasey]

When it comes to crab it's all about tough love as demonstrated by our Red Rocks. The male- generally much larger than his partner- will hold the female and wait for her to moult. This period can often take several days. If the female does not moult and the males appetite gets the best of him then he will eat her! Assuming that she doesn't become a snack mating will take place usually within a few hours. Both the female and male will open their abdomens and reveal their spermathecae and gonopods, respectively. Using his gonopods the male release packages of sperm into the female that she can hold for several months before fertilizing her waiting eggs. Need a visual? Okay!

Red Rock Crab action. [Mary Vasey]

Strangely, nudibranchs are simultaneous hermaphrodites meaning they are capable of holding both egg and sperm at the same time. The advantage to this is that when two nudibranchs of the same species cross paths they are definitely able to mate unlike if they were both males or both females. Both nudibranchs will fertilize their partners eggs and also receive sperm. The egg spirals are then laid in lacey-looking coils. These coils differ depending on the species and will be eaten readily by other species. Because nudibranchs live only a year so copulation is constant throughout the year.

So there you have it: the delicate art of marine animal courtship can be seen by you, here, at the Ucluelet (mini) Aquarium.

The shells of the veliger stage of these moonsnails are visible between the grains of sand that protect these young. [Aquarium Staff]
Sea stars release egg and sperm during broadcast spawning. These gametes are viewed under the microscope. [Aquarium staff]

-Mary Vasey, Interpreter

Monday, July 13, 2009

An Octopus' Garden

On July 12 the Ucluelet Aquarium hosted the Annual General Meeting after hours. Philip Bruecker, Founder & Chair of Building Committee, and Mark Cunnington, Director, discussed the plans and fiscal opportunities for the new permanent facility. Mark Cunnington also outlined the plans for the heat pump system that will be used. Many thanks to the approximately 50 people that were able to attend. Other business covered included the re-election of the Board of Directors, and a casual meet and greet.

The Giant Pacific Octopus is growing rapidly and is now settling in the larger rockfish tank. In this tank the numerous rocks allow for natural den building activities and the abundance of various animals allow our octopus to display more extreme hunting behaviours. Even though the rockfish and greenlings in this tank are palatable for an octopus the presence of the tastier red rock crab ensure their survival.

Our much smaller, but equally exciting, Red Octopus is warming up to her new home as well and is now often seen exploring and hunting. She has also begun investigating the field of interior decorating and can be seen shifting rocks and seaweed to make the perfect den.
The newest tank is specimen-free with the objective being of environmental significance. Our garbage tank features mostly plastic but also glass, shoes, metal, string, and other rubbish found on our beaches. All displayed trash is from the beaches either in the Pacific Rim National Park Reserve or right outside the aquarium. While broadening the understanding of the permanency of plastic waste we also acknowledge its value in maintaining our current lifestyles. Messages such as “Since 1976 plastic has been the most used material in the world” and “Plastic ropes, nets, and packaging can entangle and harm marine life” line the tank to reinforce the significance of this always growing problem.

The aquarium is open daily from 10 am until 6 pm and is located at the bottom of Main Street beside the Whiskey Docks- see you there!

-Mary Vasey, Interpreter

Wednesday, July 1, 2009

Fishy Business

The opalescent squid have hatched!!! After tending to the squid egg pods for over four weeks the work sure has paid off. In the last few days we have greeted approximately 100 new squid, about the size of a rice grain, to the Ucluelet Aquarium. They are residing in the jellyfish tank as they hatch and learn to fight the currents. Already it is evident that they are grouping together when swimming as would be the case in the wild. Their pigment spots, or chromatophores, are visibly contracting and altering the overall colour of these juvenile squid. It is interesting to note that squid have no free larval stage- after hatching as juveniles they will continue to grow and mature until reaching adult size and proportions. We expect the squid to continue to hatch in the coming days and look forward to seeing the overall results.
A juvenile squid releases ink from the already developed ink sac in response to sudden water currents [Aquarium Staff]

Juvenile squid swimming in circles after hatching one day previous. [aquarium staff]

Today we enjoyed the Canada Day celebrations hosted by the District of Ucluelet. Activities for the kids included arts & crafts and games. Free hot dogs, live music and stands from Parks Canada and local businesses were also there. Aquarium staff hosted a squid dissection and face-painting table- both were a fun success with both kids and adults from Canada and around the world.

We have a new exhibit under construction that emphasizes the impact that plastic waste has on our ocean and our environment. It is important to realize the aquarium (and our whole way of life!) would be impossible without plastic, but that it does not decompose and can have detrimental effects when not discarded with care.

With the warm water being maintained by the excellent weather we have seen many animals responding differently. The California sea cucumbers, for instance, celebrated the heat by broadcast spawning in the tanks. When examined under the microscope the collected samples suggested most were males, releasing their sperm into the water. They do this in the same manner as sea stars and some snails, hoping that with luck the broadcasted egg and sperm will connect to allow eventual larvae development.

California Sea Cucumbers release gametes into the water during a broadcast spawn session [Mary Vasey]

Happy Canada Day everyone!!!

- Mary Vasey, Interpreter