Preserving wildlife DNA for the future: Interview with Frozen Zoo's Katie Heineman

SAN DIEGO, 29 SEPTEMBER 2026 —

If you liked this story, share it with other people. Kurt, a Przewalski’s horse, was born at San Diego Zoo in the U.S. in August 2020. Less than three years later, Ollie followed. Out in the wild, their species had gone extinct in the 1960s.

At the San Diego Zoo Wildlife Alliance’s Frozen Zoo, the largest initiative of its kind in the world, genetic materials from animals and plants are stored — cryopreserved using liquid nitrogen at temperatures as low as -196° Celsius (-320° Fahrenheit) — for posterity. But the Frozen Zoo is only part of the alliance’s broader biodiversity banking initiative, which also includes a native plant gene bank and a tissue and DNA bank.

“I think of it as saving DNA for the future,” Katie Heineman, conservation program leader for biodiversity banking at the San Diego Zoo Wildlife Alliance (SDZWA), told Mongabay in a video interview. “It really is an optimistic act to conserve biodiversity for a time where we’ve solved the threats facing nature.” Applications are aplenty. Biodiversity banking can help not just in the recovery of threatened species, but also in preserving genetic diversity.

It’s also for scientific research. However, given the pace of habitat degradation and biodiversity loss, Heineman said there’s an urgency to build capacity around the world to ensure more samples are collected and preserved for genetic recovery and research. “This can’t be industrialized without an understanding of biodiversity,” she said.

“It is to tailor these methods to the diversity of life around us, and that is key to the innovation that’s needed.” Katie Heineman spoke with Mongabay’s Abhishyant Kidangoor about the biodiversity bank at SDZWA, the impact of their work, and the need to build capacity to collect more samples at scale around the world. The following interview has been lightly edited for length and clarity.

Mongabay: How did you get into the field of biodiversity banking? What attracted you to this field? Katie Heineman: I am, by training, a tropical forest ecologist. I did my Ph.D. in Panama, working with tropical forest trees. But I became really interested in conservation when I started to learn more and more about the threats that the species I was working with were facing.

In the case of Panama, it was a wind energy concession threatening our forest reserve. I am also really interested in data and how we can use data to enhance conservation. So I transitioned after my Ph.D. from working with forestry data sets to collections data sets.

Collections are amazing because they have so much data associated with them, especially in the biodiversity context from the animals and plants you collect them from and the things that we learn about them as we process them. Then there are also the outcomes that happen after we do things, especially for plants. Like planting them back out into the environment. I’m really inspired by what biodiversity collections can do for the future.

It really is an optimistic act to conserve biodiversity for a time where we’ve solved the threats facing nature. Mongabay: For someone unfamiliar with it, how would you define collections? What does it include? Katie Heineman: What our organization works on is biodiversity banking. I define that as the collection of biological materials for conservation purposes. This can take many forms. Our biodiversity bank at San Diego Zoo includes collections that are very veterinary.

They include blood samples and serum that they take from animals, and it almost serves as a blood bank. Then there’s also collections that are definitely more for applied conservation purposes, like our native plant seed bank, where we dry down and store seeds so that we can plant them back out into nature.

We also have cryogenic collections that are serving as long-term repositories for things like cells and gametes to really suspend that life in animation until we can develop new conservation technologies. Biodiversity banking is a pretty broad term, but in general, I think of it as saving DNA for the future. Mongabay: Why is it more important now than ever before to do this?

Katie Heineman: A big benefit of biodiversity banking is genetic diversity conservation. When species lose genetic diversity, they lose their ability to adapt to nature and be resilient to nature. This includes disease resistance. Having low genetic diversity decreases mating success. And so, by saving this DNA, we can do two things: We can directly increase genetic diversity when technologies exist to reintroduce that genetic diversity into populations.

We can take genetic diversity that we’ve saved in a biobank and use it to facilitate the genetic diversity of the living populations. But there’s also so much we can do just by saving DNA to learn about species, to learn about what extinction risks are present in a group of species, what predicts disease susceptibility to things like COVID and other emerging threats.

I think those are the two main avenues in which biodiversity banking can support species. You can literally create genetic diversity and put it back into populations, and you can also learn things that can really help save species by mitigating threats. Mongabay: I know SDZWA is working with different aspects of biobanking. Could you walk me through those? Katie Heineman: San Diego Zoo’s conservation programs started with the Frozen Zoo in 1975.

The Frozen Zoo is a cryogenic living collection of cell lines and reproductive materials; so that includes sperm, oocytes and embryos from primarily vertebrates. This is the first collection and really the most famous collection that we have. It’s something that’s been developed over the years by the curator of the Frozen Zoo, Marlys Houck, and was started by the founder of the conservation science department, Kurt Benirschke.

Related: San Diego Zoo Wildlife Alliance · San Diego Zoo · Katie Heineman · San Diego