Abalone Conservation Workshop
International Abalone Symposium 2012
Hobart, Tasmania
Dear Abalone Workshop Participants:
Feb. 20, 2012
Thank you for your interest in attending the abalone conservation workshop during the
International Abalone Symposium in Hobart Tasmania in May 2012. To facilitate
discussion and generate products for a publication on the results of the workshop we
have developed a series of questions to kick off the discussion and aid in creating a
draft manuscript. We intend to submit the results as a manuscript to the Journal of
Shellfish Research’s special issue on Abalone. Spend some time thinking about and
responding to these 6 questions as well as drafting conservation oriented questions you
would like to see addressed at the workshop. Please email your responses to the
questions to me before May 1, 2012 so that I may better prepare the workshop to
address the interests of you - the participants.
I thank you for your input in advance and look forward to seeing you at the abalone
conservation workshop.
Sincerely,
Error!
Laura Rogers-Bennett
rogersbennett@ucdavis.edu
Conservation of Abalone Populations
The conservation of declining and small populations is not a new problem (Caughley
1994) however abalone are unique in many ways compared with other populations in
need of restoration (Caughley 1994). Abalone, for example, are capable of producing
millions of gametes and there is a well established aquaculture industry with extensive
knowledge and experience in rearing juvenile abalone. In this workshop we seek to
explore barriers to abalone restoration as well as a way forward in partnership with
abalone aquaculturists. The need for abalone restoration is great. Many populations
that once supported wild fisheries are now in decline. One dire case is that of the white
abalone, Haliotis sorenseni, which is now close to extinction in the wild. White abalone
were listed as endangered in the United States in 2001 yet without active restoration
populations continue to decline at an alarming rate. This workshop seeks to address
these critical issues for abalone conservation
Conservation of Small Populations –
Ideas for Conservation from the UC Davis Symposium 2/10/2012
Panel Discussion with Dr. Peter Moyle: Moderator
Dr. David Wilcove – Princeton University
“Against the odds: the science, politics, and surprising success of conserving highly
endangered species”
Wilcove et al 1993 describes population size at time of listing for the US. “Alliance for
zero extinction” shows data for worldwide population sizes at time of listing
These figures represent the total pop size of primarily terrestrial plants and animals.
How would abalone population sizes at time of listing (or when we became very
concerned about them) compare?
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General public is only impacted by conservation a small amount (per person)
whereas the impact of conservations negative outcomes can be large on a few
individuals.
Question 1: At what population size should we list abalone species? What is the
minimum viable population size for abalone?
Scott et al 2010 discuss how many endangered species populations are “conservation
reliant” for the indefinite future. That is, management of threats to the population needs
to be ongoing in order for the populations to persist and to be de-listed. Conservation
actions are required to continue so that the species is not re-listed. 62% of endangered
invertebrate species recovery plans listed ongoing artificial recruitment as one of the
requirements of sustaining populations.
Question 2. What is the role of aquaculture in the conservation of endangered abalone
species? Are there incentives we can establish for abalone conservation within the
aquaculture industry.
Wilcove & Chen 1998 discuss the cost of maintaining endangered species compared
to the risk of losing those populations.
Question 3. What is the potential annual cost of artificial recruitment through
aquaculture? At what point does the risk to the population outweigh the cost of
conservation action?
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Philip Hendrick – Arizona State University
“Genetic Rescue in Small Populations”
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Genetic rescue by crossing one population with another can help increase the
genetic diversity of an endangered species in the wild (e.g. Florida panthers)
But, follow the mantra “Do no harm”
Genetic swamping by 1 or a few individuals potentially problematic
Effective population size based on inbreeding coefficient
Question 4. What are the issues with genetic diversity that we should consider when
supplementing the population with farmed seed?
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Ron Swaisgood – San Diego Zoo
“Captive breeding, reintroductions and translocations as tools to rescue small
populations”
Stamps & Swaisgood 2007 discuss the importance of the post-release environment
relative to the natal environment
- Movement vs mortality
- Conspecific cues
- Individual perception of habitat suitability – maybe based on natal habitat
Question 5. What kinds of cues might abalone use to determine suitable habitat after
translocation or artificial recruitment? How might we minimize movement (which may
increase mortality) after introduction to the new environment? Can we use more
environmentally realistic tanks for rearing seed to be stocked in the ocean?
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Josh Hull – US Fish & Wildlife Service
“Prioritizing conservation of small populations”
Emphasized collaboration among stakeholders, especially in the face of reduced
budgets.
Question 6. What kinds of collaborations will be necessary in order to maintain longterm aid for depleted abalone populations?
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Fell Free to Draft a question of your own for discussion of abalone conservation issues.