16 Feb 2023

“The amazing science of conservation physiology is a key part of our work at Chester Zoo as it helps us to provide the best possible care for our animals and may even help to protect their wild relatives.”

Conservation physiology involves measuring hormones and other biomarkers to assess and manage the reproduction, health, and wellbeing of our animals.

Lead Conservationist, Dr Katie Edwards shares everything you need to know about Conservation Physiology and Reproduction at the zoo.

A headshot of Dr Katie Edwards, Lead Conservation Scientist at Chester Zoo
Dr Katie Edwards

Our team is developing and applying new tools in conservation physiology to advance our understanding of a wide range of species and contribute to their care in zoos and in the wild.

In fact, Chester Zoo is the only zoo in Europe with a dedicated wildlife endocrinology lab, where we work with over 100 species to examine and try to treat diseases related to hormones. We divide our time between supporting animal care at zoos and breeding programmes across Europe, conducting applied conservation physiology research to expand our knowledge of species biology, and training the next generation of conservationists.

One big part of conservation physiology involves analysing poo! At Chester Zoo, we analyse a huge amount of dung from species like elephants, rhinos, okapi, fossa, and Goodfellow’s tree kangaroo. These analyses then help our animal teams to identify when a female might be pregnant or ready to mate, which ensures these endangered species have the best chances of breeding and allows us to provide the best conditions for the animals in our care. An elephant pregnancy lasts 22 months, so being able to diagnose that using their dung saves a lot of waiting!

Asian elephant Riva born at Chester Zoo in 2020

We also have projects where we are collaborating with zoos across the UK and Europe to assist with the breeding programmes for species like lowland anoa and Malayan sun bears, and we support student projects to help understand the reproductive physiology of species like cassowary, spider monkey, and bush dog, so no two days are ever the same!

We partner with the European Association of Zoos and Aquaria (EAZA) on the Reproductive Management Group to provide guidance on promoting and limiting reproduction to ensure that animals in zoos maintain as much genetic diversity as possible and that their populations are sustainable in the long-term. We also run a global Contraception Database to ensure that contraceptive protocols for wildlife are safe, effective, and reversible.

The knowledge that we gain from animals in zoos can also be used to assist with conservation efforts worldwide. A good example of this is our work with Eastern black rhinos, which was actually the focus of my own PhD back in 2008. I looked at how different factors influenced the reproductive success of black rhinos using dung samples collected from 62 rhinos across Europe, including our black rhinos here at Chester Zoo! Studies like these can then be used to help improve breeding programs to better protect this iconic species, which only had a small population of 700 in the wild at the time!

We are now supporting a Chester Zoo Conservation Scholar — Cedric Khayale — with his research into managing wild populations of black rhino in Kenya. This could have broader impacts too as the project will incorporate conservation physiology into our long-running partnership studying Asian elephants in Assam, India.

We are also developing and using tools to help understand animal health and well-being. For example, we’re working to better understand how the elephant immune system responds to a virus called elephant endotheliotropic herpesvirus (EEHV). Sadly, this virus can be fatal for young elephants; however, another Chester Zoo Conservation Fellow — Tanja Maehr — is working alongside our veterinary team and our partners at the University of Surrey to help develop a vaccine for this deadly disease, which could save many precious lives.


Become a scientist for the day! Grab your science journal and discover our five WONDERLABS to learn loads about the incredible science we do to prevent extinction!

18 February – 5 March