Tag Archives: green urchin

tafoni

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Clear sky. Light winds.
My shift of nearly-perfect-weather continues.

I was almost finished my animal census (I just needed a couple picture of areas with lot’s of animals) when a Coast Guard helicopter did two circles of the tower. A lot of Gulls took flight the Sea lions on South Rocks took to the water. I guess I’ll try again tomorrow.

The Gulls have been capitalizing on the low tides during daylight hours and have been foraging on green urchins. They leave the broken urchins on walkways, the jetty, and rock outcroppings. This time of year the urchins are full of roe (gonads) which, by Sea gull standards, is high is calories and nutrients.

Tafoni: The blocks of sandstone out a Race Rocks are leftover from building the tower stairs. There are a hand-full of rectangular blocks on the beach by the jetty. These blocks have the signature patterns of pits and holes that are cause by chemical erosion. Because the stone is permeable, saltwater infiltrates throughout the block. As the sun and wind dries the outer surfaces, the water moves outward, dissolving the clay that binds the sand particles together resulting in the surprisingly organized patterns of holes. Another driver is the physical weathering that occurs as salt dries and puts pressure on the rock particles forcing areas to exfoliate and flake. Although the science of tafoni isn’t fully understood, it is thought that there are also biological drivers, particularly in the intertidal region (Tafoni also occurs in deserts, no urchins there). Univavles and Urchins can chemically dissolve and abrade the the surface of the stone and hasten the dissolution of the pits.

-Worked on DFO boat count report
-grease gun scavenger hunt
-washed solar panels
-ran firepump and wiped it down with fluid film
 

Underwater Safari- October 1992

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In October of 1992, the diving students of Pearson College were able to help with the underwater filming for the Canadian Underwater Safari production. This series of 24 one hour television programs was broadcast live to schools and museum audiences across Canada and the US on the Anik E2 Satellite. Since that time the programs have been broadcast across the world. We have made available at this location some of the unique underwater footage which was taken by the photographer Darryl Bainbridge. The project was an experiment in using technology along with many volunteer hours to help to bring the fragile ecology of this unique area to the world. Our thanks to B.C.Parks for the intial funding to launch the production. The Royal B.C. Museum and its staff , Shaw Cable, BC Systems, BC Tel and many volunteers who provided assistance with this project.

 This video is of Pearson College student Jason Reid ( PC yr. 18) discovering a wolf eel Anarrhichthys ocellatus while the program was broadcasting live. Cameraman Darryl Bainbridge followed the huge fish for some time and caught it feeding on a green sea urchin.

OTHER REFERENCES TO THIS PROGRAM ARE IN THESE POSTS: 

 https://www.racerocks.ca/tag/underwater-safari/

Living on a shelf off the North side of Great Rocks is a Wolf Eel often seen by divers. This very gentle fish cooperated with us for one session allowing some very interesting poses. On this dive, Jason Reid (LBPC year 18) encounters the wolf eel

 

The fish shows patience while looking for its favourite food

Jason offers the wolf eel a green urchin

as it eats, clouds of urchin roe puff out of he urchin

Swimming away with his “catch”

A harbour seal was inquisitive with the divers

A gentle nose to nose with a diver

 

There was a video published by the Friends of the Royal British Columbia Museum and authored by Brent Cooke and Roger  Frampton on the Underwater Safari program: the following gives information on it.

https://www.worldcat.org/title/canadian-underwater-safari/oclc/41934389#borrow