Director’s intertidal zone

It was a sunny but windy afternoon yesterday in the intertidal zone with D block.  We saw a few things of note…

At least Ehsan & Ivan were taking note!

A dead California sea cucumber (Parastichopus californicus).  Very curious about the circumstances surrounding its arrival in the intertidal zone.

And we saw lots of eggs – several yellow whelk egg capsules and green fish eggs wedged into a crack in the rock.

We also collected some hairy hermit crabs for Tom’s extended essay work on shell selection in hermit crabs.

East Sooke Park – March 2013

First year marine scientists travelled to East Sooke Park during block week (D block on 5 March and B block on 6 March) where they explored the intertidal zone.  We saw many amazing creatures and seaweeds, including:

Spawning Nucella lamellosa with an interloping N. canaliculata on the far right.

More spawning Nucella lamellosa

Lacuna egg masses

The dwarf mottled blood star, Henricia pumila & eggs (the bright orange goo to the right of the black leather chiton, Katharina tunicata). I have not seen these eggs before and was very interested to learn that this species has only recently been described (2010) and it broods its eggs, unlike other Henricia species which are broadcast spawners.

Amit with another species of Henricia.

This nemertean Cerebratulus californiensis was crawling on the sandy beach when Alba spotted it.  Alba certainly has an eye for worms – she also spotted the nereid worm pictured below.

The worm (Nereis vexillosa) did show off its big black jaws (but not in this photo unfortunately).

Lucas found this striped sun star, Solaster stimpsoni,  which did have a commensal worm…

 

Solaster stimpsoni and its commensal scale worm,  Arctonoe vittata (seen to the right of sea star’s mouth).

Kiera found a pair of six armed stars (Leptasterias hexactis).

And Griffin found a sea leopard, Dialula sandiegensis.

The sea leopard, Dialula sandiegensis.

The brooding anemone, Epiactis prolifera, one with no offspring and the other (on the right) with many offspring!

A well camouflaged decorator crab…

…not so well camouflaged on Marc’s hand.

Mastocarpus sp. and Ulva lactuca.

Periwinkles (Littorina sitkana) in the crack of a boulder

Students had a wonderful time on Wednesday, despite the wet weather!

It only drizzled on Tuesday, but Steph still managed to get quite wet – she filled her boots!

Here is a fairly complete species list from the two days at East Sooke Park:

Haliclona sp., Halichondria panicea, Ophlitospongia pennata

Anthopleura elegantissima, Urticina crassicornis, and other Urticina spp.

Cerbratulus californienesis

Eudistylia vancouveri, Nereis vexillosa

Mopalia muscosa, Katharina tunicata, Mytilus californiensis, Diadora aspera  (with commensal worm), Littorina sitkana, Nucella ostrina, Nucella lamellosa, Nucella canaliculata, Archidoris montereyensis, Dialula sandiegensis (and egg mass)

Pollicipes polymerus, Balanus glandula, Semibalanus cariosus, Chthamalus dalli, Idotea wosnesenskii, Hemigrapsus nudus, Hemigrapsus oregonensis, Petrolisthes sp., Decorator crab, Pagurus hirsutiusculus, Pugettia producta, Cancer productus (juvenile), Cancer oregonensis

Pycnopodia helianthoides, Pisaster ochraceus, Evasterias troschelii, Henricia pumila (with eggs), and other Henricia spp., Lepasterias hexactis

Oligocottus maculosus, Gobiesox meandricus, Gunnels (one guarding eggs)

Ulva lactuca, Enteromorpha intestinalis, Acrosiphonia coalita, Codium fragile

Hedophyllum sessile, Fucus gardeneri, Nereocystis luetkeana, Macrocystis integrifolia (drift)

Mazaella sp., Corallina vancouverensis, Bossiella sp., Lithothamnion sp., Odonthalia floccosa, Endocladia muricata, Prionitis lanceolata

Fishing Frenchman?

Ivan wasn’t actually fishing – he just recovered Jon’s fishing rod!

Foggy Friday

Mesodinium rubrum bloom in Pedder Bay

The margins of Pedder Bay have been quite red recently…

This is due to a bloom of Mesodinium rubrum, a little red-coloured ciliate.

Kyle collected a bucket of water off the dock on 7 March 2013 which had some Mesodinium rubrum and looked like this:

And then again today (11 March), which looked like this:

Compared to tap water:

This is not a harmful species, but it does colour the water as a ‘red tide’.

For more information see the UBC Phytopedia entry for Myrionecta rubra.  (I love the lifestyle description of ‘kleptochloroplastidic’ which means stealing chloroplasts!)  It’s also worth doing a Google image search for Mesodinium rubrum to see images of individual ciliates and of other water coloured by blooms of Mesodinium rubrum.

Spawning feather duster worm

As the A block Marine Science second years were busily writing their practice IB exam this afternoon, a feather duster worm (Eudistylia vancouveri) was busily spawning in our seawater table.

The photos below were taken after I moved the tube worm from the plastic container it was in initially. When the worm withdrew it was like a volcano of sperm!  And then the worm slowly re-emerged…

We did have a look at the sperm under a microscope and saw that they were very active little swimmers!