By Kevin Heath
A new study has been published in the Journal of Applied Ecology by researchers at University of East Anglia (UEA) that shows captive breeding should not be the first option when trying to protect endangered species. A captive breeding programme may appear to be a good option but letting endangered species breed in the wild is much more effective.
Captive breeding is regularly used to try and conserve critically endangered species such as tigers but this can lead to animals being bred that have to stay in captivity because there is nowhere for them to be released in the wild. Captive breeding can also in some circumstances reduce normal wild breeding if eggs or animals are removed from the wild.
The study concludes that much more should be done to encourage critically endangered species to breed in the wild and to solve their population issues. This means protecting habitat and enhancing habitats to encourage breeding.
Lead researcher Dr Paul Dolman, from UEA’s School of Environmental Sciences, said: “Our research challenges the assumption that when a species is perilously close to extinction in the wild, it is always a good idea to set up a captive breeding population.
“Captive breeding can offer a last chance when species face imminent extinction, but ultimately depends on re-establishing a population in the wild. This has proved successful for some high-profile species, but in many cases it has not.
"Programmes can fail for many reasons, including delays in achieving successful breeding, failure to build up a self-sustaining population, domestication and loss of genetic diversity, and poor performance after releases into the wild. “Captive breeding can reduce motivation and resources for conservation in the wild, with disastrous consequences.
“Our research reveals the importance of objectively weighing up potential outcomes of captive breeding and comparing them with efforts to support species in the wild.”
The UEA worked with BirdLife International on the study and looked at the critically endangered Great Indian Bustard. Using population modelling and studies they found that protecting the habitat and birds in the wild would be far more effective at raising the population of the birds than running a captive breeding programe.
Dr Dolman said: “We show that only urgent and effective action to protect and extend the Great Indian Bustard’s natural habitat can prevent extinction in the wild.
“Ten years of effective habitat conservation measures, leaving eggs in the wild and not attempting captive breeding, would result in more adults in the wild than if those eggs were harvested to set up a captive breeding population.
“Our predictive models show no guarantee that a captive population could be established, and a high chance it would fail.
“Successful captive breeding with surplus juveniles released back into the wild would first require the collection of many wild eggs and a consistently ‘best possible’ performance across all aspects of the programme that would be almost impossible to achieve.
“But even the best possible captive breeding programmes need effective wild conservation to ensure released birds survive and thrive.
“Without conservation in the wild there is no point in captive breeding – as the birds would be trapped in captivity with no hope of returning to nature. Effective conservation offers a better chance to save this species, without diverting energy and funds away from the urgent action needed in its last remaining habitats.
“This type of modelling is very useful to see whether captive breeding really benefits critically endangered species.
“Importantly, it shows that conservation interventions in the wild, such as habitat restoration, should not be delayed. And if such action is taken early enough, it may remove the need for captive breeding programmes altogether.”
Understanding the best way to boost population numbers is essential for critically endangered species such as the Greater Indian Bustard. It is though that no more than 200 of the birds survive today and numbers may be as low as 100. It is one of the most endangered bird species on the planet.
Prof Nigel Collar, from BirdLife International and also an honorary professor at UEA’s School of Biological Sciences, said: “Bustards are particularly difficult to keep and breed in captivity. It can be done, but it is extremely expensive and, in trying to establish a stock of birds that breed, you are guaranteed to lose a very large number of individuals. But India cannot now afford to lose a single bird or egg in this cause. The only option is to implement a rigorous programme of habitat conservation and associated management measures, to give the species the chance to increase its numbers in the wild.
“A basic premise of captive breeding is that you have somewhere to put the animals back once you have been successful. However, if India does not immediately save the last places where the bustard survives, there will be nowhere suitable left, meaning that there is no point in captive breeding. On the other hand, if the last places are saved, the bustard could recover of its own accord–meaning that once again there is no point in captive breeding.”