SHELLFISH SPECIES
northern Abalone
Introduction
The
northern or pinto abalone, Haliotis kamtschatkana, is native to the
Pacific Ocean and lives along the North American west coast from Baja California
to Alaska. It is considered a gourmet delicacy, used predominately in Japanese and
Chinese cuisine. Market demand for abalone is believed to exceed the global market
supply, making abalone a highly valuable commodity (CAD$30-40/kilogram), and an
attractive species for aquaculture development. Traditional capture fisheries around
the world are in serious decline and many countries have imposed severe harvest
restrictions or, including Canada, an outright ban on wild fisheries. There are
significant efforts underway to establish abalone aquaculture industries in a number
of countries. Globally, aquaculture now surpasses wild production.
Abalone commercial fisheries in British Columbia were closed to all harvest in
1990 to protect the remaining population. Despite the complete ban on harvest, the
population continues to decline and is showing few signs of recovery and poor spawning
success. Poaching continues to be a major problem, motivated by high demand and
elevated value owing to the abalone’s scarcity.
Northern abalone were assigned a threatened status by the Committee on the Status
of Endangered Wildlife in Canada (COSEWIC) in April 1999. In June 2003, it was legally
listed and protected as threatened under the Species at Risk Act (SARA). Fisheries
and Oceans Canada (DFO), in collaboration with many partners, is leading a
recovery
strategy to halt the decline of the wild abalone population. One approach to meet
the objectives in the recovery strategy is to undertake research and rebuilding
experiments. This is where hatchery techniques, developed through aquaculture research
and development, come in to the picture.
Basic description
Photo Credit: Chris Pearce
Abalone is a single-shelled mollusc. The abalone’s scientific name – Haliotis
– means ‘sea ear’ and refers to its flattened, oval-shaped shell. The shell is mottled
reddish or greenish in colour, with areas of white or blue, and in the wild is often
camouflaged by growths of algae. The interior of the shell is pearly white with
a faint pink and green sheen. The flesh is creamy white, firm in texture, and has
a mild flavour.
Abalone prefer good water circulation and shallow, rocky surfaces to which they
can attach themselves firmly. They may move only a few hundred metres during their
lifetime.
Cultured northern abalone have a five year culture cycle. Farmed abalone are
typically harvested when their shell is 9 cm (3.5 inches) and weigh approximately
100 grams (3 ounces).
Background
Modest attempts to develop abalone aquaculture in British Columbia began in the
late 1980s. There has been renewed effort at improving hatchery and culture techniques
since 2000. In Nova Scotia, red abalone, Haliotis rufescens are currently
being raised from small juveniles purchased from a hatchery in Iceland.
The production cycle is typical of other farmed shellfish species consisting
of a hatchery phase (spawning and larval stages), the juvenile phase and a growout
period. Abalone are raised in land-based facilities where temperature, water circulation
and feeding cycles can be tightly controlled to promote animal health and growth.
Sea water is pumped into the hatchery and is generally filtered to minimize bacterial
growth.
Larval and young juvenile abalone are raised from healthy, robust broodstock.
Spawning, fertilization, nurturing of larvae, larval settlement on nutrient-rich
firm surfaces and first feeding, all of which occur within a two week period, present
critical challenges for the producer. The juvenile abalone are then separated, to
reduce crowding, and are transferred into larger tanks. They remain in these tanks
until they measure 5-10 mm in length, which can take between 10-12 months. From
here, juvenile abalone are ready to be transferred into other tanks, typically shallow,
land-based raceways. The animals remain in these tanks until harvest time.
Abalone use a rough, file-like ‘tongue’ to scrape microbial films from rock surfaces.
They will also feed on suspended algal particles and floating kelp fronds from the
surrounding water. There has been some experimentation with prepared feed pellets
to augment their diet under culture conditions. For a more detailed description
of the hatchery and grow-out process, please read the
species profile prepared by
the BC Shellfish Growers Association.
Photo Credit: Chris Pearce
Research Activity
There is currently one collaborative abalone aquaculture project underway in
British Columbia – the
Bamfield-Huu-ay-aht Community Abalone Project (BHCAP) – located
at the Bamfield Marine Sciences Centre. Partners in the project include the Huu-ay-aht
First Nations, the
Bamfield Marine Sciences Centre, and the Bamfield Community School
Association. The project’s primary focus is to, "replenish wild abalone populations
and to remove it from its threatened status. The project includes a hatchery and
grow-out facility to breed and raise abalone for reintroduction into the wild."
[Source: BHCAP website] Divers take a percentage of the hatchery-raised larvae and
juvenile abalone and ‘outplant’ them to the ocean in areas offering the highest
chance for survival (suitable habitat with nutritious food source and protection
from predators). Regular dive surveys are conducted to count and measure the abalone
to gauge their survival rate and growth progress. Read more about this project in
the Winter 2007
newsletter published by the Bamfield Marine Sciences Centre (page
5).
This project has also experienced some recent retail success from the growout
or aquaculture phase of the project. They are providing a specialty supply of market-size
abalone to a high-end restaurant in Vancouver. These proceeds from these sales –combined
with revenue raised through financial penalties levied against abalone poachers
convicted under the Fisheries Act, as well as financial contributions from
the federal and provincial government (between $1.8M and $2.3M) and in-kind assistance
from the Bamfield Marine Sciences Centre including students and community volunteers
– assist in the recovery work (out-planting of hatchery raised abalone).
The invaluable information gained through the research and development of hatchery
and grow-out techniques is contributing to the growing body of knowledge of abalone
aquaculture. Progress is slow however, raising abalone to market size takes time
(at least four or five years) and significant capital investment and technical expertise
to sustain the operation until any tangible results are observed. Expansion of commercial
aquaculture of northern abalone will require a regulatory change to the Species
at Risk Act.
For more information
BC Shellfish Growers Association – Species Profile
- Provides a detailed description of the hatchery and grow-out process
under development for abalone aquaculture.
Fisheries and Oceans Canada
Species at Risk Act Public Registry – Species Profile
- Provides a description of wild abalone as well as research, monitoring
and recovery activities.
The Bamfield Huu-ay-aht Community Abalone Project
- This website describes the project and provides updates.
BHCAP and BMSC evaluating the results of the abalone outplanting experiments
(Winter 2007)
- This article on page five describes the survey work to assess the progress
of an abalone enhancement project in Barkley Sound, British Columbia.
An Emerging Canadian Industry Comes Out of its Shell (March 2007)
- This article summarizes an innovative success story of red abalone,
Haliotis rufescens, in Nova Scotia. The company, Atlantic Abalone,
purchases juveniles from Iceland.
International Abalone Society
- The International Abalone Society (IAS) is an international forum, intended
to promote research on abalone, facilitate the distribution of information
on abalone, and promote cooperation between abalone researchers and members
of the abalone industry.
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