SAN DIEGO (Dec. 1, 2025) — In a significant conservation milestone, San Diego Zoo Wildlife Alliance has successfully cryopreserved cells from the critically endangered Lord Howe Island stick insect to its world-renowned Frozen Zoo®, marking the first time an insect has been included in the world’s largest and most diverse collection of living biomaterials. This achievement provides a critical safeguard for a species once thought to be extinct and opens new possibilities for insect conservation and genetic rescue.
“Adding the Lord Howe Island stick insect to the Frozen Zoo reflects our commitment to protecting all wildlife, big and small, and it establishes a model for how cryopreservation can be applied to other threatened insects,” said Carly Young, laboratory manager, San Diego Zoo Wildlife Alliance. “These cryopreserved samples are creating a powerful resource for the future that can help restore genetic diversity and support the long-term resilience of this extraordinary species.”
The Lord Howe Island stick insect, a large, flightless invertebrate endemic to the Lord Howe Island Group in the Tasman Sea, was presumed extinct in the wild by 1930. Decades later, in 2001, the species was rediscovered when a tiny population was found surviving on a single shrub on the steep, rocky slopes of Ball’s Pyramid, a volcanic outcrop located about 12 miles from Lord Howe Island. To save the species, one breeding pair was carefully collected and brought to the Australian mainland to establish a secure breeding program at Australia’s Melbourne Zoo. San Diego Zoo Wildlife Alliance joined the partnership in 2012 to establish an assurance population in North America, advancing a vital effort to secure the species’ long-term‑ survival. Visitors to the San Diego Zoo can see these rare, nocturnal insects in a specialized habitat at the Zoo’s Wildlife Explorers Basecamp.
This milestone coincides with San Diego Zoo Wildlife Alliance’s celebration of the 50th anniversary of the Frozen Zoo, a pioneering resource that has set the standard for conservation and cryopreservation science worldwide. Recently, the Alliance also cryopreserved the first plant contributions to the Frozen Zoo, samples from endangered Nuttall’s scrub oak, expanding the collection’s impact across kingdoms. Adding the Lord Howe Island stick insect as the collection’s first insect marks a historic achievement for invertebrate preservation and highlights the Frozen Zoo’s enduring global impact over five decades. As the Frozen Zoo enters its next half-century, San Diego Zoo Wildlife Alliance will continue advancing innovation to preserve the planet’s biodiversity for generations to come.
About San Diego Zoo Wildlife Alliance San Diego Zoo Wildlife Alliance, a nonprofit conservation leader, inspires passion for nature and collaboration for a healthier world. The Alliance supports innovative conservation science through global partnerships and groundbreaking efforts at the world-famous San Diego Zoo and San Diego Zoo Safari Park, both leading zoological institutions and accredited botanical gardens. Through wildlife care expertise, cutting-edge science and continued collaboration, more than 44 endangered species have been reintroduced to native habitats. The Alliance reaches over 1 billion people annually through its two conservation parks and media channels in 170 countries, including San Diego Zoo Wildlife Explorers television, available in children’s hospitals across 14 countries. Wildlife Allies—members, donors and guests—make success possible.
About San Diego Zoo Wildlife Alliance’s Frozen Zoo® The Frozen Zoo® is the world’s first large-scale cryogenic biological bank dedicated to preserving living cells and reproductive material from wildlife—and remains the largest, most diverse collection of its kind. Founded in 1975 by Kurt Benirschke, M.D., the Frozen Zoo today holds cell lines from more than 11,500 individuals representing more than 1,300 species. Stored in liquid nitrogen at minus 320 degrees Fahrenheit, the collection includes cells, embryos and gametes from mammals, birds, reptiles, amphibians, fish, plants, marine invertebrates and insects. The Frozen Zoo is one of six unique San Diego Zoo Wildlife Alliance biobanking collections that make up its Wildlife Biodiversity Bank. Together these collections offer a variety of approaches to preserving biodiversity. Learn more at sdzwa.org/frozen-zoo.
