A pioneering conservation initiative has been launched to safeguard one of the United Kingdom’s most iconic and vulnerable butterflies, the British Swallowtail (Papilio machaon britannicus). This remarkable insect, native exclusively to the unique wetland ecosystem of East Anglia—principally the Norfolk Broads—has become the focus of cutting-edge research aimed at reversing its alarming population decline through advanced cryopreservation techniques. By seeking to preserve genetic diversity and facilitate future restoration efforts, this project represents a seminal moment in invertebrate conservation biology within the British Isles.
The British Swallowtail is critically dependent on fenland habitats, which are increasingly imperiled by climate change, habitat degradation, and genetic bottleneck effects arising from its confined range. Since the 1970s, butterfly populations in the UK have experienced an 80% decline in abundance or distribution, with the British Swallowtail subspecies alone suffering a 57% population decrease over the past two decades. Although recent conservation measures have stemmed the fall somewhat, the species remains classified as vulnerable on the GB Red List, necessitating innovative scientific interventions to avert further loss.
To address this dire conservation challenge, researchers from Anglia Ruskin University (ARU) have partnered with Jimmy’s Farm & Wildlife Park and the UK-based biobank specialist Nature’s SAFE—an organization pioneering cryobiology applications in conservation contexts. Together, they are investigating the feasibility of cryopreserving butterfly eggs by employing vitrification and ultra-low temperature storage protocols in liquid nitrogen at approximately -196°C. This technique, well established in vertebrate and plant cryobiology, is being trailblazed for use in Lepidoptera for the first time, aiming to establish a viable genetic reservoir for long-term species recovery initiatives.
The project uses eggs from Papilio machaon gorganus, a European subspecies housed in thriving captive populations at Jimmy’s Farm & Wildlife Park, as a model system. This subspecies shares a close genetic affinity with the British Swallowtail but enjoys a more robust and stable population, making it an ideal surrogate for refining cryopreservation methodologies. By refining protocols for egg freezing and thawing, researchers aim to determine whether developmental success and subsequent reproductive fitness can be maintained post-thaw, benchmarking these variables against control groups derived from unfrozen eggs.
This experimental approach involves subjecting butterfly eggs to controlled cryoprotectant exposure followed by rapid cooling to inhibit ice crystal formation—a primary cause of cell damage. The eggs are then stored in liquid nitrogen storage tanks, where metabolic activity virtually ceases. After variable storage intervals, eggs undergo rapid warming and are reared under regulated laboratory and field conditions to assess viability, hatching rates, larval development, pupation success, and adult fecundity. These parameters are critical for validating cryopreservation as a conservation tool for invertebrate taxa traditionally considered challenging for genetic banking.
The implications of this research extend far beyond the British Swallowtail. Successfully establishing a cryopreservation protocol for Lepidoptera eggs could revolutionize conservation biology, providing a scalable, cost-effective method to safeguard genetic diversity across numerous endangered insect species. As pollinators face mounting pressures globally from habitat loss, pesticides, and climate change, biobanking solutions such as this have the potential to bolster food security, ecosystem services, and biodiversity preservation in the Anthropocene era.
Dr. Alvin Helden, a prominent ecologist and member of the Applied Ecology Research Group at ARU, emphasized the novelty and significance of the research. He noted that despite recent positive fluctuations in native butterfly numbers, long-term trends for the British Swallowtail remain threatening. Helden remarked on how integrating empirical fieldwork with laboratory cryobiology techniques would forge new frontiers in insect conservation, underscoring the potential for this to be the world’s first successful cryopreservation of a butterfly species.
Jimmy Doherty, founder of Jimmy’s Farm & Wildlife Park and an advocate for conservation science, reiterated the importance of synergizing practical breeding programs with technological innovation. His institution contributes vital captive populations and expertise in entomological care, facilitating the experimental manipulation required to optimize cryopreservation success. Jimmy’s Farm serves as a living laboratory where invertebrate conservation is actively championed, demonstrating a model for private sector collaboration in biodiversity preservation.
Nature’s SAFE, represented by COO Debbie Rolmanis, highlighted the broader ramifications of their involvement. She pointed out that breakthrough techniques developed in this project could be extrapolated to other critical pollinator and invertebrate species, whose ecological roles in food production and natural ecosystems are indispensable yet increasingly imperilled. By building expertise in cryobiological conservation, Nature’s SAFE aims to deliver transformative benefits for global biodiversity and biotic resilience.
Technically, the research leverages advances in cryoprotectant formulation, such as optimized ethylene glycol and dimethyl sulfoxide concentrations, coupled with ultra-fast cooling rates that mitigate intracellular ice nucleation—historically the limiting factor in insect egg cryopreservation. Researchers must also address challenges like differential permeability of egg chorion layers and the metabolic sensitivity of embryonic stages to freezing stress. A successful protocol will need to balance cryoprotectant toxicity, osmotic shock avoidance, and precise thermal control.
The project’s methodology includes repeated cycles of freezing and thawing to simulate storage scenarios, followed by rigorous phenotypic assessment of larvae and adults. Molecular analyses, including genetic marker evaluation and epigenetic imprinting studies, are planned to ensure no sub-lethal developmental defects arise as a consequence of cryostorage. Data will be statistically compared to baseline populations to confirm that cryopreservation does not compromise genetic integrity or population viability over successive generations.
If proven effective, this approach would enable the strategic creation of a cryobank for the British Swallowtail, supporting conservationists in executing captive breeding, genetic diversification, and reintroduction programs with the assurance of a secure genetic backup. This model could be adapted worldwide for other endangered insect species, fundamentally reshaping conservation triage by incorporating cryobiology as a frontline tool.
In summary, this collaborative effort unites academic research, wildlife management, and conservation biotechnology, positioning cryopreservation as a cutting-edge strategy to confront biodiversity loss in invertebrates. It exemplifies the critical intersection of applied ecology and innovative science to counteract the mounting pressures threatening complex ecological networks. Through diligent scientific inquiry and interdisciplinary partnership, the future for the British Swallowtail and potentially countless other pollinators is rendered more hopeful.
Subject of Research: Conservation biology and cryopreservation of the British Swallowtail butterfly (Papilio machaon britannicus)
Article Title: Cryopreservation as a Novel Strategy to Preserve Britain’s Endangered British Swallowtail Butterfly
News Publication Date: Not specified
Web References:
- Anglia Ruskin University: https://www.aru.ac.uk/
- Jimmy’s Farm & Wildlife Park: https://jimmysfarm.com/
- Nature’s SAFE: https://www.natures-safe.com/
Image Credits: Photograph by Mark Collins, Swallowtail & Birdwing Butterfly Trust
Keywords: Cryopreservation, Extinction, Conservation ecology, Conservation policies, Conservation genetics, Insects, Lepidoptera, Endangered species
