Learn more about and follow the White Abalone Captive Breeding Program on our website, Twitter, Instagram, Facebook, and TikTok.
This page focuses on the WAC Lab beginning in 2022, when Alyssa became the PI. For previous work under direction of Dr. Kristin Aquilino and our amazing team of other white abalone heroes, please see the White Abalone StoryMap or the website linked above.
SAVING THE ENDANGERED WHITE ABALONE
Abalone are marine snails that once supported rich commercial and recreational fisheries. So rich, in fact, that overfishing reduced white abalone populations to less than 1% of their historical abundances. The white abalone fishery was closed in 1996, with closures of commercial fisheries for all other abalone species in California following within a year. In the span of a few decades, an ecologically critical group of species nearly disappeared from waters off of California, bringing with them a way of life for Indigenous people, colonizers, and immigrants. Because abalone are broadcast spawners and so few of them remain in the wild, the recovery of this iconic species relies on captive breeding and outplanting.
After disease hampered early breeding efforts, the program headquarters moved to UC Davis Bodega Marine Laboratory in 2011. Between antibiotic cleansing baths and exfoliating, coconut oil and beeswax treatments, our white abalone healthcare plan now reads like a relaxing spa retreat. With healthy animals and a great deal of collaboration among scientists, aquarists, and aquaculturists to help get the animals “in the mood” for spawning, captive production skyrocketed, from just a few dozen produced during the 2012 spawning season to tens of thousands annually.
The National Oceanic and Atmospheric Administration now lists white abalone as one of its eight “Species in the Spotlight,” those species most at risk of going extinct in the near future. Happily, captive breeding efforts bring new hope to recovery efforts, and we are excited to start pilot outplanting work in the next few years. By replacing overhead pipes with towering kelp forests and swapping out submersible pumps for steady ocean swells, we hope our precious baby snails might save their species from the verge of extinction. Captive-bred white abalone were released into the wild for the first time in 2019.
As of August 2022, I am thrilled to have been passed the White Abalone Captive Breeding Program Director baton from Dr. Kristin Aquilino. The White Abalone Captive Breeding Program integrates research, mentoring, and outreach among lab groups within UCD BML and among state and federal agencies, aquariums, and commercial aquaculture facilities (see list of partners below). Our research focuses on reproductive conditioning, improving post-settlement survival, and enhancing the genetic integrity of our broodstock.
Our goal is to crack the code of white abalone gametogenesis, and help the program make as many babies as possible each year. We use tools that span nutritional physiology, reproductive physiology and hormone manipulation, molecular biology, and more to improve reproductive output of white abalone. Our core work and research is funded by NOAA through a Section 6 award. Other funding sources for specific research projects are mentioned below.
After disease hampered early breeding efforts, the program headquarters moved to UC Davis Bodega Marine Laboratory in 2011. Between antibiotic cleansing baths and exfoliating, coconut oil and beeswax treatments, our white abalone healthcare plan now reads like a relaxing spa retreat. With healthy animals and a great deal of collaboration among scientists, aquarists, and aquaculturists to help get the animals “in the mood” for spawning, captive production skyrocketed, from just a few dozen produced during the 2012 spawning season to tens of thousands annually.
The National Oceanic and Atmospheric Administration now lists white abalone as one of its eight “Species in the Spotlight,” those species most at risk of going extinct in the near future. Happily, captive breeding efforts bring new hope to recovery efforts, and we are excited to start pilot outplanting work in the next few years. By replacing overhead pipes with towering kelp forests and swapping out submersible pumps for steady ocean swells, we hope our precious baby snails might save their species from the verge of extinction. Captive-bred white abalone were released into the wild for the first time in 2019.
As of August 2022, I am thrilled to have been passed the White Abalone Captive Breeding Program Director baton from Dr. Kristin Aquilino. The White Abalone Captive Breeding Program integrates research, mentoring, and outreach among lab groups within UCD BML and among state and federal agencies, aquariums, and commercial aquaculture facilities (see list of partners below). Our research focuses on reproductive conditioning, improving post-settlement survival, and enhancing the genetic integrity of our broodstock.
Our goal is to crack the code of white abalone gametogenesis, and help the program make as many babies as possible each year. We use tools that span nutritional physiology, reproductive physiology and hormone manipulation, molecular biology, and more to improve reproductive output of white abalone. Our core work and research is funded by NOAA through a Section 6 award. Other funding sources for specific research projects are mentioned below.
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Using reproductive hormones to improve spawning
The hormonal processes underlying abalone reproduction are not well-characterized, which limits our ability to improve reproductive conditioning for white abalone. One neuroendocrine peptide of particular interest in all abalone is gonadotropin-releasing hormone (GnRH). GnRH plays a role in gametogenesis and reproduction in many vertebrates and invertebrates, and has been shown to lower time to reproductive readiness and increase the percentage of animals that reach gonadal maturation. Injections of GnRH isoforms in other abalone species were successful at inducing gametogenesis and the high conservation of GnRH across taxa indicates that this methodology can be applied to white abalone. We are currently exploring the use of injections of synthesized white abalone GnRH during the months leading up to spawning.
Developing tools for monitoring the impact of climate change on captive abalone reproduction and digestion
Funding: California Sea Grant Aquaculture 2022 Award to Lead PI Dr. Donovan German. Doctoral student Newton Hood (UC Irvine) is also leading this work.
There is an accumulating body of evidence that the maternal diet and energetic status of many marine invertebrates, particularly in species with non-feeding larvae like abalone, strongly influences both larval size and juvenile growth through maternal provisioning of resources in eggs and yolk (Pechenik et al. 1998; Marshall et al. 2007). Lipids may be of particular importance in settlement and metamorphosis of abalone larvae as they are in other invertebrates (Byrne et al. 2008). As much of the early life energy sources are yolk lipids (Moran & Manahan 2003), the amount of lipids allocated to offspring may be one of the factors impacting early life survival. Indeed, this maternal provisioning of lipids to offspring can affect survival under ocean acidification conditions and may be related to genetic variation or lineages of red abalone (Swezey et al. 2020). Exactly how those lipids are digested and acquired remains understudied, especially in white abalone. Because there is limited data on abalone lipid digestion at physiologically relevant temperatures, understanding the mechanistic links between and maternal acquisition of those lipids and downstream reproductive physiology and production is currently impossible. Our understanding of lipid digestibility in other species highlights the importance of determining these links. Our work has three objectives:
Objective 1: Determine the impact of maternal diet composition and digestive physiology on spawning success and egg quality in red abalone.
Objective 2: Determine the impact of high temperature conditions, and diet manipulation as a mitigation tool, on gut function, GnRH expression, gonad development, and spawning success.
Objective 3: Develop methods of measuring GnRH in aquaculture facility water as a mechanism to understand natural GnRH cycles, and as a predictive tool for reproductive success in captive abalone.
Objective 1: Determine the impact of maternal diet composition and digestive physiology on spawning success and egg quality in red abalone.
Objective 2: Determine the impact of high temperature conditions, and diet manipulation as a mitigation tool, on gut function, GnRH expression, gonad development, and spawning success.
Objective 3: Develop methods of measuring GnRH in aquaculture facility water as a mechanism to understand natural GnRH cycles, and as a predictive tool for reproductive success in captive abalone.