Monthly Archives: December 2001

Wind!

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Thursday, December 06, 2001
Good Evening
TEMPERATURE: Max 8.8C — Min 4.5C — Reset 7.7C Rain 5.0 mm — Windy day
WEATHER: A great weather day! Very noisy with the howling and whistling 35-46knt. winds out of the west.At times the rain, moderate and horizontal, reduced visibilty to 1/2 mile as some of you may have noticed on cameras #1 and #3. The constant pounding of the waves,especially during high tide causes the house to ‘rumble’ not unlike small earthquakes.
MARINE LIFE: The dead mammal is a very small Harbour Seal, looked to be about 8 or 9 kilos and 70cms. There are no external wounds, however the seal seems under sized with not much body fat, and for some reason failed to thrive.It would appear that it has been dead for 2 or 3 days and came ashore on a flooding tide in a knot of kelp and driftwood.
Many of the sea lions rafted about in the relative calm sea in the lee of Gr. Race while 40-50 Harbour Seals spent several hours ‘surfing’ in the 3-4metre breakers between the Southeast Rocks and Gr. Race
posted by Carol or Mike S at 6:08 PM
Good Morning
WEATHER: Sky Overcast — Vis. 15 Miles — Light Rain Shower — Wind South West 23 Knots — Sea 4 Foot Moderate
posted by Carol or Mike S at 7:19 AM

Parastichopus californicus The Race Rocks Taxonomy

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 Video of Albinism and Leucism in Sea Cucumbers

 

 

 

 

Video of escape response when attacked by Pycnopodia sp.

 

 

 

 

Video of a male sea cucumber releasing sperm

 

 

 

Emily finds a partially albino (pinto?) Parastichopus while diving near Church Island… just up the Strait from Race Rocks. 

 

 

DESCRIPTION:

The California Sea Cucumber grows up to 50cm long. They are the largest cucumbers in B.C. waters. They range in colours from red in juveniles to brown or mottled brown, with all white individuals occurring rarely. They are covered on the dorsal side with flesh coloured papillae, and on the ventral side by tube feet. A circle of peltate feeding tentacles surround a subterminal mouth, directed ventrally at the anterior end. Oxygenated water is forcibly pumped into the sea cucumber’s respiratory trees in several successive inhalations, and then deoxygenated water is forcefully expelled. Eye-witness accounts have noted small fish being expelled with this force of water, perhaps living in symbiosis with the California sea cucumber.

RANGE:

Gulf of Alaska to Cedros Island, West of Lower California. Intertidal to 249m. Common on mud, gravel, shell, rock rubble or solid bedrock, from exposed coast to sheltered inlets. Greatest densities occur in quieter waters where organic sediments settle on hard surfaces. Harvesting of Sea Cucumber is also done by divers, throughout their range.

FEEDING, BEHAVIOR, AND BREEDING:

Sea cucumbers feed as they move along the bottom, traveling up to a maximum of 3.9m a day. They gain nutrition from organic material in sediment, mostly form bacteria and fungi. California Sea Cucumbers cease feeding and become dormant from September to early March. Once they reach maturity at four years of age, they will migrate to shallow water to spawn from late April to August, although this timing varies with location. Fertilization takes place in open water. Free swimming larva feed on plankton for 35-52 days before settling to the bottom. Parastichopus californicus has few natural predators. Sunflower starts sometimes eat them, and the sea cucumber reacts strongly by rearing back and flexing violently to avoid being eaten. They are harvested commercially in B.C., Washington, and Alaska for meat, and limits have been set for the amount that may be caught. When disturbed, as other sea cucumbers, it will contract and squirt a powerful stream of water from its posterior end. Five pairs of muscle bands which run the length of the body help this organism in contracting and escape from sea stars. Perhaps one of the most interesting features is this organisms ability to regenerate new organs for winter after expelling them during its dormant phase. It seems there is controversy as to whether sea urchins expel or reabsorb their organs. Recent evidence cited by Philip Lambert of the RBC museum in Victoria(1997) indicates that the sea cucumbers reabsorb their organs.

FURTHER INFORMATION NEEDED:

-further study at Race Rocks of commensal fish living in respiratory tree

-behaviour studies

-colouration, how long it takes to occur in full pigmentation, as a white individual found near Race Rocks has recently begun to change tan colour–later development?

-mechanism of absorbing/ejecting and regenerating organs

WEBSITE LINKS TO SEA CUCUMBERS:

Sea cucumber fishery – Pacific Region
http://www.pac.dfo-mpo.gc.ca/ops/fm/shellfish/Sea_Cucumber/biology_cucumber.htm

A paper by Phil Lambert on Sea Cucumber Taxonomy
http://rbcm1.rbcm.gov.bc.ca/nh_papers//taxing.html

REFERENCES CITED:

Carefoot, Thomas (1977), Pacific Seashores : A Guide to Intertidal Ecology
Lambert, Philip (1997), Sea Cucumbers of B.C., Southeast Alaska and Puget Sound
Morris, Abbott, Haderlie (1990), Intertidal Invertebrates of California
pearsonlogo2_f2The 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 control webcams.  – Sarah Trefry Dec 2001 (PC)

Other Members of the Phylum Echinodermata at Race Rocks 
taxonomyiconReturn to the Race Rocks Taxonomy
and Image File

Tonicella lineata: lined chiton–The Race Rocks Taxonomy

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Lined chitons are seen frequently by divers in the 5-15 meter depth at Race Rocks. Their color is highly variable, some being a turquoise colour while others are brown with white markings on some of the shell segments as noted on those in this video clip. Observe in particular, the patches of grazed Lithothamnion sp. , the pink encrusting algae.

 

Characteristics:

Tonos (stretched/braced) Cell, lineatus (lined/marked with lines).

The lined chiton eats the surface layers of this encrusting algae, including the film of diatoms and other small organisms on it.

All chitons have a muscular foot for locomotion, a complete digestive tract from the mouth to the anus, a calcium carbonate shell with 8 overlapping plates. This is produced by the mantle, where organs are suspended in coelom. A gill extracts oxygen and disposes waste, a chiton exposed to air consumes only 73 percent of the amount it does when submerged. It remains in oxygen debt until re submersion. Even though the body has bilateral symmetry, the gill numbers on both sides may very well be irregular, asymmetrical.

Physical Description: The lined chiton- Tonicella lineata -covered by 8 smooth plates,. Endless colour variations exist. The girdle around the plates is smooth and leathery, often with a row of lighter spots or bands. Size up to 5 cm long.


It is brightly colored, having a zigzagging dark black/ brown lines over a background of yellow, orange, pink, orchid, and lavender predominate. This aids in its camouflage around the Lithothamnion coralline algae, where it is usually found.
Geographical Range: Aleutian Islands to San Miguel Island, CA, Sea of Okhotsk, Northern Japan
Habitat: They live on rocks covered with coralline algae that are in the low intertidal or subtidal zone. They can also be found in urchin burrows in the rock.
Feeding: They eat encrusting coralline algae.
Predators:Predators of this invertebrate are sea stars, Pisaster ochraceus and Leptasterias hexactis. Harlequin ducks, and the river otters..
Reproduction: Dioecious broadcast spawners. Spawning occurs in the spring. The males release their sperm into the water while exhaling waste water. Females release a stream of green eggs. Larvae metamorphose into juveniles approximately 12 hours after having settled on coralline algae.
Adaptations: Larval development stops unless the larva settles on coralline algae, which is its food source. This alga also acts as camouflage, as the chiton is often of the same colour.

Possible Further Studies:
The behavior in different depths.
The reproduction cycle of the lined chitons.

Kingdom Animalia
Phylum Mollusca
Class Polyplacophora
Order Neoloricata
Suborder Ischnochitonina
Family Ischnochitonidae
Genus Tonicella
Species lineata
Common Name lined chiton

  • References:
    http://www.wallawalla.edu/academics/departments/biology/rosario/inverts/Mollusca/Polyplacophora/Tonicella_lineata.html

Ecology and reproductive biology of Tonicella lineata (Wood, 1815)(Mollusca-Polyplacophora), by JR Barnes, 1972

The larval settling response of the lined chiton Tonicella lineata, by J. R. Barnes and J. J. Gonor, MARINE BIOLOGY, Volume 20, Number 3, page 259-264, 1973

http://wikis.evergreen.edu/marinelife1011/index.php/Tonicella_lineata

Andy Lamb and Bernard P. Hanby, Marine Life of the Pacific Northwest, Harbour Publishing p. 176

Adam Sedgwick , Magazine: Proceedings of the Royal Society of London, Vol. 33, (1881 – 1882), pp. 121-127
Morris, R.H. et al. Intertidal Invertebrates of California. (Stanford: Stanford University Press, 1980)

Other Members of the Phylum Arthropoda at Race Rocks 
taxonomyiconReturn to the Race Rocks Taxonomy
and Image File
pearsonlogo2_f2The 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 control webcams.

 December 2001 – Bassam( Jarbawi (PC year 27)

 

 

Tour Boat Disturbance

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Wednesday, December 05, 2001
Good Evening
TEMPERATURE: Max 6.1C — Min 3.3C — Reset 4.9C — Rain 0.8 mm
HUMAN INTERACTION: Two groups of students came over in 2nd Nature this afternoon to learn the intricacies of the desalination plant that provides our fresh water. Two tour boats were in the reserve at 14:40 one of which did approach Middle Rock a little too close and caused some Sea Lions to take to the water. I think actually having people standing so high on an observation deck was very threatening to the animals. Garry happened to be in the tower so obtained this video of the disturbance:
http://www.racerocks.com/racerock/archives/videcotourimpact.htm
Sadly we have a dead marine mammal at the base of the ridge along the east shore of Great Race. Even with the telescope I cannot tell whether it is a Harbour Seal,an Elephant Seal or a California Sea lion and I can’t get close enough without disturbing the 50 or so Sea Lions and 2 Elephant Seals hauled out all around to make a positive ID.MARINE LIFE: At approximately 16:00 we saw 6 or 7 Orca just east of North Rocks, unfortunately it was too dark for filming but what a sight! There was one very large bull in the group and one quite small Orca, possibly a calf. They were breaching and slapping their tails and really churning up the sea. They started out in fairly large circles diving, porpoising and rolling and the large bull breaching quite often. After about 10 minutes the circles got smaller and they started swimming very fast on their sides with their dorsals at about a 45 degree angle to the water. They were quite low in the water and were sort of ‘plowing’ the water,back and forth,around and around.Finally with the telescope we did see the reason for all the activity, one unlucky California Sea Lion. Twice the Sea Lion was tossed in the air. We watched until it was too dark to see anything except a few white splashes. As all this was going on there was a group of 30-40 sea gulls circling over-head ready to snatch up any ‘crumbs’ that might come their way -nothing is wasted in this example of the food chain.
posted by Carol or Mike S at 6:08 PM
Good Morning
WEATHER: Sky Cloudy — Vis. 15 Miles — Wind North West 5 Knots — Sea Rippled
posted by Carol or Mike S at 7:19 AM

Rosedale Breakers!

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Tuesday, December 04, 2001

 Good Evening
TEMPERATURE: Max. 6.9C — Min 2.9C — Reset 4.8C — Rain 5.6 mm no Snow
posted by Carol or Mike S at 6:19 PM
HUMAN IMPACT: The racerocks.com group went to the island today to drop off a Sony camera with Carol and Mike. Carol and Mike have been requested by Fisheries (DFO) to record the ecological impact of the DND blasting that is to occur tomorrow at Rocky Point. Often, by the third blast, the sealions are scared off the rocks, possibly resulting in injury. Many of the sealions on Race Rocks have quite large scars on their undersides. Sealions are also scared by boats passing too close to the rocks.
ENVIRONMENT: We were treated to the rare sight of two Rosedale breakers. These breaking waves are the result of long, high energy waves, generated in the Pacific Ocean. When the waves reach Rosedale Reef, the most shallow point in the area, the pent up energy causes the wave to break. Refer to http://www.racerocks.com/racerock/data/data.htmto get a link to NOAA/NCEP Wavewatch for more information.We can see that the snow is building up on the Olympic Mountains with the snow line moving down almost daily. At this time of year the clearcuts are quite visible.
posted by Damien Guihen at 5:19 PM
Good Morning
WEATHER: Sky Overcast — Vis 15 Miles — Wind West South West 15 Knots — Sea 2 – 3 Foot Chop
posted by Carol or Mike S at 7:22 AM

Bald Eagle takes seagull

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Monday, December 03, 2001
Good Evening
TEMPERATURE: Max 7.1C — Min 4.3 Reset 4.7C — Rain 0.6 mm
Marine Life:Three mature Bald Eagles arrived in the area this morning about 11:15 ,one perched on the ‘look-out’ log on N.Rks while the other two shared a high point on the SE Rocks. all was quiet for over an hour when one of the two took flight, circled the rock twice,swooped behind the rock and reappeared with an immature gull in it’s talons.As the eagle with the gull landed the other two eagles started harassing the successful hunter to the point the it flew off leaving the now dead gull.I expected to see the other two eagles move in on the prey however they just remained on the ridge about a metre away from the gull just watching.Finally the third eagle came back,the other two took flight and the three eagles spent about 5 minutes flying at each other often with their talons out-stretched.At last one eagle left the fray swooped down made an unsuccessful grab for the gull then just continued flying north towards Pedder Bay.The other two flew over to West Race, sat there about 10 minutes then flew off towards Whirl Bay.Why the eagles left the gull I don’t know but it did not go to waste as the ever vigilant crows soon moved in for a meal!
A Great Blue Heron spent 11/2 hours in the East Bay area just below the tower then flew off towards Pedder Bay.Also a group of Black Oyster Catchers arrived just at sunset and settled among the rocks on the east side of Gr. Race.
posted by Carol or Mike S at 6:10 PM
Good morning
WEATHER: Sky Cloudy — Vis. 15 Miles — Wind West 7 Knots — Sea Rippled — Occasional Light Rain Shower
posted by Carol or Mike S at 7:32 AM

Students out for weekend

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Sunday, December 02, 2001
Good evening
TEMPERATURE: Max. 8.9C — Min. 5.1C — Reset 5.1C — Rain 5.5 mm
Human Interaction: A group of students under the direction of Laura Verhegge spent the weekend on Race Rocks doing some field work in environmental systems studies. Wanting to take advantage of the low tides which are occurring after dark the students arrived late Friday afternoon.The weather at times was cold,wet and windy -so windy in fact the the return to campus scheduled for 11:30 Saturday had to be postponed to Sunday forenoon.
posted by Carol or Mike S at 6:10 PM
Good morning
WEATHER: Sky Part Cloudy — Vis. 15 Miles – Wind East 8 Knots — Sea Rippled
posted by Carol or Mike S at 7:22 AM

Report on work with racerocks.com –June – December 2001

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Report on Ecological Reserve warden Garry Fletcher’s work with racerocks.com . June- December 2001
This past half year my focus has been on a number of areas related to the development of the racerocks.com site as an educational resource.
1. In June I had a student present a live webcast from us at Race Rocks at the AMTEC conference in Halifax.  At the same time we were demonstrating this technique to two representatives from APPLE computers Educational Staff, Keith Mitchell,Internet and NewMedia Technology, Apple Learning Interchange  from Texas and Jeff Orloff, Senior manager, Learning Products Education marketing and Solutions,  from the head office in California.
2. In the first two weeks of June, I again had two students staying out at Race Rocks presenting some live webcasts and working on the development of Quick time archived video and Quick Time Virtual reality  movies (see at) http://www.racerocks.com/racerock/archives/vrindex.htm
3. Development with Apple Learning Interchange of the Conference Room and The Discussion Forum for Race Rocks. In July, I worked with Keith Mitchell in the creation of these two interactive parts of the website. On the Meeting Room Conference site, we now are able to receive written questions from an audience and direct them around to different cameras while retaining the link with our mobile camera.  We used this with a presentation for a conference at South Western University in August.

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