Tag Archives: Orca

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

Orca visit

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Wednesday, October 31, 2001


WEATHER: Max 10.1ºC — Min 8.1ºC — Reset 8.9ºC Rain 14.6mm
Total Rain fall 108.1mm for the month of October 2001- Mean high temp. 11.5ºC — Mean low temp. 8.1ºC
MARINE LIFE: A blustery start to the day again but the weather did not seem to bother the mature Bald Eagle that arrived shortly after 9:00 and stayed for over two hours.We noticed the second visitor at 12:50 just west of Gr. Race,a lone transient bull Orca. He ‘cruised’ along the shore of North Rocks and Gr. Race and then into the kelp bed on the east side of Gr. Race.The Harbour seals were very agitated,crowded together close to shore, bobbing up and down to watch for the whale. Interestingly several groups of sea lions(steller&california) followed along about 200′ behind the Orca. Watched through the telescope one group of 10-12 sea lions follow the Orca about a mile east when we lost sight of them.

 

 

Necropsy and Skeletal Mount of Orca L51- 1999

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Orca L51 Removed From the Strait of Juan de Fuca
On the weekend of September 25, 1999 a dead female Orca was reported by a Canadian Coast Guard employee, Wayne Ingalls.
It was floating in the area of Christopher Point near Bentinck island at the eastern end of the Strait of Juan de Fuca, just adjacent to Race Rocks. On Tuesday, the 28th we were informed at Pearson College and a team of students from the diving service went out to secure the body in a small bay near the Point.

The Orca Skeleton mounted at Pearson College

Orca Skeletal Mount at Pearson College

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The Finished product of the work of skeletal preparation of L51 is now  suspended above the lab benches in Catrin Brown’s Biology Lab. The mount was made by students and Hans Bauer, a former faculty member who volunteered for the job, along with Hugo Sutmoller.

See the flensing of the orca L51 by Pearson College students

 

 

 

A serious contaminant of Orcas in the southern Vancouver island area is PCBs. Male Orcas accumulate these chemicals throughout their life, whereas females are purported to increase in levels until a birth, whereupon the levels in the tissue drop as a result of lactation.

For more information on contaminants in the Orca Food web, see the following Link:

“Is Victoria Sewage Contaminating Southern Resident Killer Whales?“
A Technical Submission to the SETAC Victoria Sewage Scientific and Technical Review Panel
By Gerald Graham, Ph. D. Marine Environmental Consultant
On behalf of the T. Buck Suzuki Environmental Foundation

 

ORCA skeleton assembled

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This article appeared in the Jnuary 17 , 2002  number 8 issue of the Collge newspaper

It’s a grand jigsaw puzzle – hundreds of bones, huge and tiny, all to be reassembled into the skeleton of a whale. Graduates returning to the June reunion will know the first whale project, and everyone at Pearson since then will know the vast frame of a whale erected behind the swimming pool. The present Orca project is well underway, and, happily for those currently working on it, well past the smelly stage.

Biology teacher Catrin Brown, a team of students, and Han Bauer, the first Biology teacher at Pearson, took the project a stage further this week, examining the skeleton of a porpoise – rather easier to fit into lab space! – in order to understand better the structure of the killer whale. Catrin gives us following explanation.

Catrin’s Explanation

In September 1999, a 27-year-old female killer whale known as L-51 was found dead in the waters off Race Rocks. Her death was presumably the result of a prolapsed uterus from a difficult childbirth a few months before, and fate of her young calf was unknown.

A team of Pearson divers towed the whale ashore, where it was disembowelled and transported back to the college in gorey chunks. Sections of the carcass were then suspended from the college docks, where ocean life feasted on the decaying meat over a period of months. Eventually the clean bones emerged and after a summer of drying and bleaching in the sun, the smell receded and the promise of a skeleton took shape.

At this stage outside help was sought, and found in the person of Hans Bauer, Biology teacher at the founding of the college, who is now retired and living in Sydney, near Victoria. With his good humoured guidance, students tackled the task of removing some of the more tenacious marrow by boiling the large bones in large vats over a fire. Many students have been involved in various stages of this project including Katy Green (year 25), Joao Marquez (year 26), Francoise Guigne (year 27) and Jaffar Saldeh (year 27).

We are now close to the stage of reassembling the bones into a permanent mount for display on campus. As the population of killer whales inhabiting the Juan de Fuca Strait has recently been declared an endangered species, L-51 is likely to be a focal point of interest.

January 17, 2002. number 8.

Victoria’s killer Whale Early Warning System Dec 1986.

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By Robin Baird –From The Cetacean Watch Newsletter , Dec 1986.
A discussion of Victoria’s Killer whale early warning system, and the installation of the first hydrophone at Race Rocks.

robin

Marcus Pistor ( PC student) Pam Stacey and Robin Baird installing the hydrophone cable on the south-east side of Great Race Rock.

cetacean

Social organization of mammal-eating killer whales: group stability and dispersal patterns

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by Robin W. Baird and Hal Whitehead
See the full PDF:KWSocOrg
Abstract
: The social organization of mammal-eating “transient” killer whales (Orcinus orca) was studied off southern Vancouver Island from 1985 through 1996. Strong and long-term associations exist between individual transients, so sets of individuals with consistently high association levels, termed pods, can be delineated. Pods consist of individuals of mixed ages and sexes, and typically contain an adult female and one or two offspring (averaging 2.4 individuals). The mother–offspring bond remains strong into adulthood for some male (and less often for female) offspring. Other males disperse from their maternal pod and appear to become “roving” males, spending some of their time alone, and occasionally associating with groups that contain potentially reproductive females. These males appear to have no strong or long-term relationships with any individuals, and adult male – adult male associations occur significantly less often than expected by chance. Females that disperse from their natal pod appear to be gregarious (having high average association rates) but socially mobile (having low maximum association rates). Differences in social organization from the sympatric fish-eating “resident” killer whales (where no dispersal of either sex occurs) likely relate to differences in foraging ecology. Transient killer whales maximize per capita energy intake by foraging in groups of three individuals,whereas no such relationship has been documented for resident killer whales