Monthly Archives: June 1999

Scott Wallace: Research on Abalone in BC Reserves.

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Scott Wallace did research in 1997 and 1998 at Race Rocks with Pearson College divers. He studied the population dynamics of the Northern Abalone,Haliotis kamtchatkana. His research was done as part of a PhD thesis in Resource Management from the University of British Columbia in Vancouver.

Wallace, S. S. 1999. Fisheries Impacts on Marine Ecosystems and Biological Diversity:
The role for marine protected areas in British Columbia. Ph.D. Dissertation. The University of British Columbia. Pp. 198.

Wallace, Scott, S. 1999, Evaluating the Effects of Three Forms of Marine Reserve on Northern Abalone Populations in British Columbia, Canada.

graphsizedistribConservation Biology, Vol 13 No 4, August, 1999, pages 882-887.

ABSTRACT: :Marine reserves have been suggested as tools for assisting the management of fisheries by protecting vulnerable marine species from overexploitation. Although there is a theoretical basis for believing that marine reserves may serve as management tools, there are few marine reserves in the world in which to test their effectiveness. My research evaluated three forms of marine reserve on the south coast of Vancouver Island, British Columbia, Canada. I used northern abalone (Haliotis kamtschatkana), a severely depleted shellfish in this region, as an indicator of the effectiveness of the reserves. Abalone populations in eight sites receiving different degrees of spatial protection were counted and measured in situ during the spring of 1996 and 1997. In all sites with enforced harvest closures, populations of abalone were greater, and one site with nearly 40 years of protection had on average much larger (older) abalone. Reproductive output, as a function of abundance and size, was also greater in the enforced reserve areas. Larval dispersal from reserves, and hence the benefit to exploited areas, was not formally surveyed. Nevertheless, the results of my study, combined with knowledge of present abalone populations, life history, and regional hydrodynamics, suggest that establishment of reserves is justified in the absence of perfect knowledge of larval dispersal. (Link to fulll article)

See the Abalone taxonomy file for videos of Scott’s work.

https://www.racerocks.ca/haliotis-kamtschatkana-northern-abalone-the-race-rocks-taxonomy/

Intertidal Invertebrates on the West shore of Great Race Rocks

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westshoreThe intertidal zone on the West side of Great Race Rocks as viewed and photographed on June 12, 1999 at a minus 0.1 tide. The predominant macroalgae is Hedophylum sp. although immature bull kelp (Nereocystis luetkeana) is also anchored in this zone close to the shore. westisleThe small island on the North West corner is completely exposed at low tide but submerged at high tide. It contains a rich assortment of hydroids as well as other invertebrates where Dr. Anita Brinckmann-Voss has collected specimens at the zero tidal level.

 

Small pink dots of a Melobesia mediocris, a calcareous pink encrusting algae which grows as an epiphyte on the leaves of surf grass.phyllospadix

pinkgreenJust below the green fringe of surf grass, Phyllospadix scouleri, pink hydrocorals and other hydroid survive the current and wave swept zone.

abietinariaanthopThe hydroid Aglaophemia latirostris with an Intertidal Anemone. 

 

 

 

 

3anthopleuraOther Cnidarians such as the green anemone, Anthopleura xanthogrammica, are found in the low intertidal area. These large anemone with symbiotic algae are also found in the surge channel on the south-west corner. The knife placed in the picture for scale measures 10cm in length.

redblueurchGiant red urchins Strongylocentrotus franciscanis live here at the upper limits of their range and the purple urchin,  Strongylocentrotus purpuratus also inhabits a narrow band in this area.

handnubilusA giant barnacle, Balanus nubilus plays host to a colony of Symplectoscyphus turgidus  (formerly  Sertularella turgida) . Hydrocoral, (Allopora sp.) encrusts much of the substrate

gfcave2Two of the small caves at this level yield a variety of invertebrates. The ceilings of these caves usually support a variety of hydroids

rrpeg7caveThe floor of this cave on the south-west corner is covered with the red encrusting sponge,  Ophlitaspongia

purpleurchinHere on the small island, the purple urchins reside in a crevasse next to the mussle Mytilus californianus.

 

 

 

 

 

 

Harbour Seal Boat Impacts

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rmsept2009decapsealThis dead harbour seal pup was the first of two found in a single week in Sept 2009 in the waters near Race Rocks. A boat traveling at great speed decapitated this animal and left another slice on the neck in the tell-tale pattern of propeller wounds.

 

 

 

CASE STUDY: CONTROL OF SPEED OF BOATS
IN THE RACE ROCKS PILOT MARINE PROTECTED AREA

With the increase of marine ecotourism in the Southern part of Vancouver Island, the incidence of boats coming in contact with marine animals has become an issue. Commercial Whale-watching companies operating out of Victoria have contributed to a significant increase in boat traffic in the Race Rocks area, and although some respect the speed limits of the reserve, others have been slow to catch on. We recommend that boats proceed very slowly (no noticeable wake) and avoid coming too close to marine mammals or feeding and nesting marine birds. In the 1998 summer, at least three baby seals were struck and killed by boat motors. Baby Seals lie near the surface of the water and have no innate fear of rapidly moving boats. Adult seals and sea lions also occasionally get hit.

One example of a marine mammal collision is documented below from the Bamfield area. We present it here as a reminder to those in motor boats that speed must be controlled especially near marine mammal colonies. Our thanks to Sue Sanders and Nathan Webb of Bamfield Marine Station for the following information:

cutsealDate: Wed, 09 Jun 1999:

The seal in the picture was found by the driver of the School Boat, as he was dropping kids off on their way home, he was in the middle of Grappler Inlet, in Port Desire. (not sure if you are familiar with Bamfield- West side- Vancouver Island). This is a relatively sheltered area, but boats do go speeding through there. The driver contacted me at the station, as he thought perhaps I would be able to help the seal ( I am a small animal veterinarian as well as a PhD grad student). I went back to the site where the seal was with the driver, and using a large fish net we were able to get him out of the water and onto the boat. By the time we got to him he was barely able to maintain himself at the surface. Once in the boat he initially thrashed around a little, but then calmed down as soon as I placed my hands on him. As you can see from the picture, there was a large facial injury to the right side of his head, with a lot of musculature missing. Based on the amount of bleeding at the time of our recovery of the seal I would say he had lost a lot of blood, there was also frothy blood from his nostrils and mouth. I listened to his lungs and felt that there was significant fluid within the chest cavity also. Given the extreme nature of his injury and his poor condition I elected to euthanize him to alleviate further pain and suffering. In my opinion, I do not believe he could have survived even with major medical intervention, if such facilities had been available. I think this poor seal was on the verge of drowning, in addition to his severe injury, that appears to have been from a propeller. Good luck with your pilot study, emphasizing safe boating practices, and speed reduction is essential. I think people generally expect that marine animals will get out of the way of boats, but as we know this is not always the case.”

cutsealBy Sue Sanders
Bamfield