Can queen conch aquaculture save the species? New publication suggests limitations

A new article published in the journal Oryx examines the efficacy and perception of queen conch (Aliger gigas) conservation aquaculture—cultivating aquatic organisms to manage or replenish natural populations. In particular, the paper evaluates conservation aquaculture as a viable strategy to enhance fisheries production and rebuild declining, overexploited populations.

The paper asserts that queen conch aquaculture is useful for scientific inquiry, community engagement and education, but if species recovery is the goal, then an interdisciplinary approach to restoration should focus more broadly on managing natural populations. Above all, protecting natural breeding aggregations of conch should be prioritized for species recovery and the ancillary benefits to marine ecosystems and human livelihoods.

"The culture of queen conch from eggs to the juvenile stage has been perfected through decades of research in laboratory and hatchery settings, and land-based culture remains an essential tool for understanding the biology of this important species," said Dr. Allan Stoner, chief scientist at Community Conch and senior author on the paper. "However, because of high natural mortality, no field release of cultured conch has resulted in successful repopulation to date."

The lifecycle of queen conch, in which most animals naturally perish, creates a significant barrier that aquaculture has yet to overcome. The paper uses examples that enumerate and illustrate the challenge.

Based on a review of past studies, 4,000 juveniles would have to be released for a single individual conch to survive to adulthood. The authors then estimated the number of adult conchs harvested annually in a typical industrial fishery and determined that to offset only 10% of the catch would require releasing 2.8 billion juvenile conchs annually. This feat across the broader Caribbean is unrealistic and staggering.

The sheer magnitude of animals that would have to be raised for repopulation makes aquaculture ecologically and economically unfeasible as a significant source of replenishment to reverse the impacts of long-term overharvest. Proactive fisheries policies that sustain natural reproduction are a more realistic and cost-effective means of replenishing depleted conch populations.

"There's no single, simple solution for ensuring a sustained harvest of queen conch, so we need a holistic approach to conservation and sustainable management that benefits the species, the fishery and the planet," said Dr. Andy Kough, research biologist at Shedd Aquarium and lead author.

"We suggest using strategically linked marine protected areas that allow adult aggregations to replenish other areas. We also need more informed fishery policies that include education and outreach, so communities understand what the data shows us and ultimately support common-sense policies."

The paper emphasizes that conch aquaculture should be encouraged as a means of furthering scientific knowledge, inspiring local conservation ethos and increasing community support, while also being realistic about its limitations for repopulation efforts.

Ultimately, the study provides an unbiased perspective on the opportunities and limitations of queen conch aquaculture, so governments, environmental organizations and aquaculture practitioners can set objectives for the conservation management of the species.

The authors include a variety of conch researchers representing eight institutions, including government, academic and non-profit conservation organizations.