by Ryan Murphy, April, 2010 See Ryan’s underwater set on Flickr with a range of invertebrates:
In the early 1980’s while doing subtidal surveys, we discovered a major concentration of the small subtidal sea cucumber Pseudocnus curatus ( formerly Cucumaria pseudocnus) living in high density off the West side of Great Race Rocks. On April16, 2004, six divers, Ramiro, Mael, Mike, Carmen, Aven and Chris were able to do a preliminary survey of the area and have produced the results shown here. To do the survey, they ran out a reel tape measure from shore to 75 meters in a bearing of 255 degrees magnetic from peg number 7- a permanent reference peg on the very South West corner of the Island. This took them into water that is 8 to 10 meters in depth. We are uncertain as to why this organism concentrate here in these numbers, and this also happens at other locations such as Beecher bay 3 km to the West. This is the only area we find them in at Race Rocks. Also included in this file are the raw data values from the divers. One may clip and paste these into an EXCEL program in order to do alternate analysis.
This species is distinguished fromCucumaria pseudocuratawhich lives up in the mussel beds by having 10 tentacles instead of 8. It is s found in great abundance on the surface of boulders at a depth of 10 meters 60 meters offshore of the south west tip of Great Race Rock ( peg7) Counts of up to 1000 per square meter have been estimated. It can also be found intertidally among the mussel beds on the Western side of the main island.
The following count done by students of the diving activity gives an idea of how dense this species is in one location at Race Rocks. Recently Ryan Murphy found another population of this density on the Eastside of Great Race Rock. The book Sea Cucumbers of British Columbia, Southeast Alaska, and Puget Sound by Phil Lambert is the best source for identification of most of the 45 species of local sea cucumbers. In it he notes that the habitat of Pseudocnus curatus “in the Juan de Fuca Strait tends to be shallow subtidal in areas where the tidal currents are strong….. They nestle together in large aggregations on open rocky surfaces …..and….. are eaten by many species of sea stars……although their body wall is toxic to some fish predators providing a strong defense mechanism.” See also Taxing Problems by Philip Lambert – Now Curator Emeritus of Invertebrates, Royal BC Museum for a description of the difficulty in classification and the need to classify by the skin ossicles. Google Pseudocnus curatus for a link to the page describing this species..
Pseudocnus curatusIs similar to another species, Cucumaria pseudocuratawhich is found more shallow in the intertidal zone at Race Rocks. Both species average 1.5 to 3cm in length. C. pseudocurata has 5 bands of tube feet in single or zig zag rows. As a rule there are 8 equal sized tentacles. P.curatus on the other hand has 10 equal sized tentacles. and tube feet scattered on the Dorsal side. At Race Rocks, it lives in the subtidal zone at 8 to 10 meters in depth.
Domain Eukarya Kingdom Animalia Phylum Echinodermata Sub-Phylum Eleutherozoa Class Holothuroidea Subclass Dendrochirotacea Order Dendrochirotida Family Cucumariidae Genus Pseudocnus Species curatus, (Lambert,1997?) Common Name: Black brooding sea cucumber
POPULATION DISTRIBUTION at RACE ROCKS
In the early 1980’s while doing subtidal surveys, we discovered a major concentration of the small subtidal sea cucumberPseudocnus curatus ( formerly Cucumaria pseudocnus) living in high density off the West side of Great Race Rocks. On April16, 2004, six divers, Ramiro, Mael, Mike, Carmen, Aven and Chris were able to do a preliminary survey of the area and have produced the results shown here.
To do the survey, they ran out a reel tape measure from shore to 75 meters in a bearing of 255 degrees magnetic from peg number 7- a permanent reference peg on the very South West corner of the Island. This took them into water that is 8 to 10 meters in depth.
We are uncertain as to why this organism concentrate here in these numbers, and this also happens at other locations such as Beecher bay 3 km to the West. This is the only area we find them in at Race Rocks.
Also included in this file are the raw data values from the divers. One may clip and paste these into an EXCEL program in order to do alternate analysis.
The Race Rocks taxonomy is a collaborative venture originally started with the Biology and Environmental Systems students of Lester Pearson College UWC. It now also has contributions added by Faculty, Staff, Volunteers and Observers on the remote controlwebcams.
Some interesting research about the population dynamics of these birds and the effect on the host species that they parasitize is contained in that article.
Domain Eukarya
Kingdom Animalia
Phylum Chordata
Sub-Phylum Vertebrata
Class Aves
Order Passeriformes
Family Icteridae
Genus Molothrus
Species ater
Common Name: Brown-headed cowbird.
The Race Rocks taxonomy is a collaborative venture originally started with the Biology and Environmental Systems students of Lester Pearson College UWC. It now also has contributions added by Faculty, Staff, Volunteers and Observers on the remote controlwebcams.
This brightly coloured bryozoan, Disporella separata, can grow in patches 30- 40 cm in diameter. It may initially be mistaken for the purple variety of the Pink hydrocoral Allopora sp. It is found on the rocks right off the docks at Race Rocks in 8-12 metres of water.
The purple bryozoa, Disporella separata- Photo by Ryan Murphy
This brightly colored bryozoa can have patches 30- 40 cm in diametre. It may initially be mistaken for the purple variety of the Pink hydrocoral Allopora sp. It is found on the rocks right off the docks at Race Rocks in 8-12 metres of water
Rich : Animalia
Tribe : Bryozoa ( Moss animals)
Class : Stenolaemata
Order : Cyclostomatida
Family : Lichenoporidae
Gender : Disporella
The Race Rocks taxonomy is a collaborative venture originally started with the Biology and Environmental Systems students of Lester Pearson College UWC. It now also has contributions added by Faculty, Staff, Volunteers and Observers on the remote controlwebcams.
General Description:Aconthodorishudsoni is a typical representative of the Dorid Nudibranchs, which are also often referred to as sea slugs. Nudibranchs are sea snails that lack a shell and can vary greatly in coloration and form. That is why they are known as one of the most beautiful marine animals. Acanthodorishudsoni can be easily identified by its transparent whitish body and the yellow stripe running at the edge of its mantle. Its body is covered with conical pipalae, which are also tipped yellow. As most nudibranchs, Aconthodorishudsoni has two long tentacles (called rhinophores) which are used as sensory organs for searching for food or a partner.
Sea slugs occupy the benthic zone. They usually live in the lower intertidal zone and could be found up to 700m in depth.
The dorid nudibranchs (over 3000 species) are widely spread throughout the world. Aconthodorishudsoni, however, could be found only on the Pacific coast of North America.
Size: 1.5 to 2 cm
Feeding:
Dorid nudibranchs feed on a wide variety of organisms: anemones, corals, hydroids, sponges, etc. However, they are highly specialized in their feeding habits. Some nudibranchs can eat only one specific genus or even species! Presently, it is not known what is the exact diet of Acanthodorishudsoni, but biologists believe that it should be similar to the one of the other members of the genus Acanthodoris – bryozoans.
Reproduction:
Sea slugs are hermaphrodites. Usually, they lay their eggs nearby a food source. The incubation period lasts for about 50 days, but can range in accordance to the abiotic factors in the environment. Nudibranchs go through a larval stage and when conditions are favourable, they metamorphose into young adults. This helps them distribute to larger areas.
Biotic Associations:
Although the dorid nudibranchs would be usually found on top of rocks, sometimes they live on other organisms, such as corals, seaweeds, and sponges, and exhibit parasitic relationships.
The Race Rocks taxonomy is a collaborative venture originally started with the Biology and Environmental Systems students of Lester Pearson College UWC. It now also has contributions added by Faculty, Staff, Volunteers and Observers on the remote controlwebcams.
This is an enlarged close up of part of the image above.
This species is currently being identified. Each polyp is smaller than 1.2cm. Although it may appear at first as a hydroid, it is actually a soft coral, in known as an octocoral because of the eight tentacles. It is found in small patches a few cm. in diameter on the rocks right off the docks at Race Rocks in 10-12 metres of water.
Dr. Anita Brinckmann Voss identified this sample and indicated that it is related to Gersemia the soft pink coral. She has seen it in samples from Race Rocks before but not in such a large colony. She also indicated that a new species has been described from the North Pacific and she will try to get us a reference to it.
Another photo by Ryan Murphy of a Clavaria colony. The colour difference here is unexplained so far.
Domain
Eukarya
Kingdom
Animalia
Phylum
Cnidaria
Class
Anthozoa
Subclass
Octocorallia
Order
Alcyonacea
Family
Clavulariidae
Genus
Clavularia
Species
sp .
Common Name:
Pale soft coral
Octocorals on Coral reefs make up a large portion of the species there. The potential medicinal uses of several species of clavularia have been published. The abstract of one such study on Clavularia viridis is shown below:
Lin YS, Khalil AT, Chiou SH, Kuo YC, Cheng YB, Liaw CC, Shen YC. of the Department of Marine Biotechnology and Resources, National Sun Yat-Sen University, Kaohsiung 804, Taiwan, Republic of China. Abstract
Chemical investigation of the nonpolar extract of soft coral Clavularia viridis resulted in isolation of five new prostanoids, designated as claviridic acids A-E (1-5, resp.), in addition to the known clavulones I-III. Their structures were determined on the basis of spectroscopic techniques, especially HR-ESI-MS, CD, and 2D-NMR experiments. The isolated marine prostanoids exhibited potent inhibitory effect on PHA-induced proliferation of peripheral blood mononuclear cells (PBMC), as well as significant cytotoxic activity against human gastric cancer cells (AGS)
This file is provided as part of a collaborative effort by the students, faculty, staff and volunteers of Lester B. Pearson College
Pam Birley took this photo using the remote cam 5 on February 6, 2010. We have had difficulty identifying it but it looks quite like a Laysan Albatross. Below is a quote from Pam:
“Thought I would draw your attention to this mystery bird, seen on Middle Rock on Saturday. I was actually looking at the seals but this large bird caught my eye because it was so white. I wish I had taken more pictures but only saved this one. It was larger than the Cormorants (Beside it in the photograph) and had a big yellow/orange beak. It was white except for the wing area which was black. It was not a double-crested Cormorant. The only thing I can come up with from Sibley and consulting the internet is a Laysan Albatross. Apparently they only breed in the Hawaiian Islands area but do travel up to the Bering Sea, Alaska and the Pacific NW.” PAM BIRLEY, UK
The Race Rocks taxonomy is a collaborative venture originally started with the Biology and Environmental Systems students of Lester Pearson College UWC. It now also has contributions added by Faculty, Staff, Volunteers and Observers on the remote controlwebcams. April 2010- Pam Birley
Ryan Murphy took these pictures in October 2011 and followed up in getting the identifications sorted out between this shrimp and Pandalus danae . See his pictures on Flickr: When Ryan took this image on the right, , he happened to get the small red tentacled a animals in the left of the picture. These are a new phylum for our records, rhe Phoronids.
The Race Rocks taxonomy is a collaborative venture originally started with the Biology and Environmental Systems students of Lester Pearson College UWC. It now also has contributions added by Faculty, Staff, Volunteers and Observers on the remote controlwebcams. March 15 2010- Ryan Murphy
Myxicola infundibulum , a slime tube worm is one of the Polychaetes in the Phylum Annelida. It is fairly common among the vast array of other invertebrates living subtidally at Race Rocks.
Ryan Murphy took this underwater picture in April of 2009 at Race Rocks. It captures the transparency well.
Domain
Eukarya
Kingdom
Animalia
Phylum
Annelida
Class
Polychaeta
Order
sabellida
Family
sabellide
Genus
Myxicola
Species
infundibulum
Common Name:
jelly tube worm
Slime worm by Ryan Murphy April 2010
This file is provided as part of a collaborative effort by the students, faculty, staff and volunteers of Lester B. Pearson College
Saxidomus gigantea by Ryan Murphy, April, 2010 This is a common intertidal clam, usually however not found in an ecosystem such as Race Rocks, but rather on sandy or mud beaches. Find the other invertebrates in the image also . Chitons, a top snail, and the tentacles of a sea cucumber.
Domain Eukarya
Kingdom Animalia
Phylum Mollusca
Class Bivalvia
Subclass Heterodonta
Order Veneroida
Family Veneridae
Genus Saxidomus
Species gigantea(Deshayes,1839)
Common Name: Buttter Clam
The Race Rocks taxonomy is a collaborative venture originally started with the Biology and Environmental Systems students of Lester Pearson College UWC. It now also has contributions added by Faculty, Staff, Volunteers and Observers on the remote controlwebcams. March 15 2010- Garry Fletcher
Rhamphocottus richardsonii, the Grunt Sculpin– Image by Adam Harding
This small sculpin ( up to 9cm) is rarely seen or photographed at Race Rocks, but it is probably quite common. It walks on its pectoral fins.
Domain Eukarya
Kingdom Animalia
Phylum Chordata
Sub-Phylum Vertebrata
Class Actinopterygii
Order Scorpaeniformes
Family Rhamphocottidae
Genus Rhamphocottus
Species richardsonii
Common Name: Grunt Sculpin
(Gunther 1874)
The Race Rocks taxonomy is a collaborative venture originally started with the Biology and Environmental Systems students of Lester Pearson College UWC. It now also has contributions added by Faculty, Staff, Volunteers and Observers on the remote controlwebcams.
by Ryan Murphy, April, 2010 See Ryan’s underwater set on Flickr with a range of invertebrates:
