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The BBC recently published a wonderful article detailing what they describe as an “audacious plan” to save the northern white rhino, of which there are two left in the whole world – both female. This plan involves using specially designed equipment to harvest eggs from the remaining rhinos, putting them on an emergency flight from Kenya to Italy for in vitro fertilisation with stored male sperm and then bringing them back to Kenya where scientists are studying how best to inseminate southern white rhino surrogates. With such a huge commitment of time, effort and resources, a sceptic could be forgiven for asking ‘is it worth it?’ So this Endangered Species Day, we are asking why should we save endangered species?
Loss of other species
The first argument for saving an endangered species is the fact that losing one species can often lead to the loss of other species. This occurs by causing an imbalance in the ecosystem and is easily seen after the removal of a top predator, in a phenonmenon called a trophic cascade. The most well-cited example of the impact of this is the reintroduction of wolves into Yellowstone National Park in 1995 after they were lost to hunting earlier in the century. The return of the wolves has helped control the coyote population, which has in turn helped provide more prey for large bird species. The wolves’ hunting of the elk has helped stop over-grazing, enabling tree and plant species to recover. The presence of the wolf helps a whole host of other species survive.
Loss of ecosystem functionality
The types of imbalances described above can also have huge impacts on the ecosystem’s functionality and the benefits it provides, known as ecosystem services. Healthy ecosystems provide us with clean water, food, climate regulation, resources and oxygen, as well as aesthetic and cultural value. For example, Walsh et al. (2016) found that it could cost up to US$163 million to reverse the loss of water clarity caused by a trophic cascade triggered by a tiny invasive water flea in Lake Mendota in Wisconsin. This shows that even the smallest and most insignificant-seeming species can have huge impacts on the services we humans take for granted. As can the genetic diversity that we can’t see – biodiversity provides immense value to the pharmaceutical and cosmetics industries through the use of plant proteins.
Lost forever
The thing with endangered species is that, generally, once they’re gone they’re gone. We don’t have the luxuary of realising we’ve made a mistake and asking for them back. Children born today will never see a mystical Yangtze river dolphin, a beautiful golden toad, a majestic Javan tiger or, if conservation efforts fail, a great northern white rhino. By the time they are old enough to travel independently, the world is predicted to have lost nearly all of its coral reefs and much of the Earth’s biodiversity will likely be experiencing extensive pressure and disruption from climate change (Trisos et al. 2020). A UN report last year found that “around one million species already face extinction, many within decades”. We have to ask ourselves if this is something we are comfortable stealing from future generations?
But, as Cambridge conservation professor Andrew Balmford says in his book, Wild Hope: “in trying to ensure that policy makers and the public at large appreciate the seriousness of the problem, maybe we’ve focussed too much on the negative”. It is important to remember to look to the positives on a day like today because the success stories are out there. The Yellowstone wolves are one, but also the reintroduction of the great Califonian condor, the recent rebound of humpback whale numbers and the protection of the very special grey slender loris here in Sri Lanka, to name but a few. There is everything still to fight for so we must take our lead from the scientists working so determinedly to save the northern white rhino and throw all we can into our conservation efforts.
References:
1. Northern white rhinos: The audacious plan that could save a species. Clare Spencer, BBC News. 14 April 2020. https://www.bbc.com/news/world-africa-52228181
2. Invasive species triggers a massive loss of ecosystem services through a trophic cascade. Walsh et al. (2016), PNAS. https://www.pnas.org/content/113/15/4081
3. The projected timing of abrupt ecological disruption from climate change. Trisos et al. (2020), Nature. Link
4. Global assessment report on biodiversity and ecosystem services of the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services. Brondizio et al. (2019), IBPES Secretariat. https://ipbes.net/global-assessment
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