Bringing back lost species

Feb 25

Bringing back lost species

February 25th 2023

Ireland’s tattered ecosystems are so far down the path of collapse that most people have got used to the idea that our island is not the place for wild nature that can simply be allowed to look after itself. I am used to hearing that what we have is a ‘managed landscape’, although mismanaged might be closer to the truth.

Yet, contrary to this belief, Ireland has not broken free of the rules of nature and restoring fully-functioning, self-regulating, natural ecosystems (bogs, forests, rivers, coastal and ocean ecosystems) is an essential task for the coming century.

Ecosystems don’t work without the species that hold them together and you might think that even if our bogs and forests are in bad shape we would at least have an idea of what plants and animals should be present and in what numbers.

Sadly no. We are, in the words of Aldo Leopold, “playing a game of chess with nature” but can only “dimly see the board, the men, or the rules”.

Indeed, we know that many of the pieces are missing, but we don’t even fully know which ones they might be.

Traditional ecology has elevated the concept of the ‘native species’, broadly considered to be a plant or animal that was present before the arrival of humans.

Notwithstanding that certain alien invasive species have resulted in drastic, negative changes to local ecologies, this notion has not served us well in Ireland.

Red deer, badgers, hedgehogs, frogs, natterjack toads and, most recently, the strawberry trees of the south-west, are all increasingly believed to have been introduced by people.

Does this render them unworthy of conservation?

The list of animals that we are certain were here before the arrival of humans (remembering that there is debate even about when this was) is thin.

Among them is the Eurasian lynx, although there is scant evidence for its presence – a single femur from a Waterford cave that has been dated to nearly 9,000 years ago. For many, this is too little evidence from too long ago; a single bone tells us precious little about the lynx population that might have existed while the changes that have taken place to our landscape in the intervening millennia have been so extensive as to render any talk of reintroduction moot.

This last point seems to have been endorsed by a recent study led by Colin Guilfoyle at the Atlantic Technological University that found that (on purely ecological grounds) the chances of survival of lynx in Ireland after 100 years was low due to poor availability of habitat and poor connectivity between those areas of habitat that were otherwise suitable. This conclusion shouldn’t come as a surprise but, rather than ruling out the feasibility of bringing back the lynx, it instead shows what we need to do for such an undertaking to be successful.

What of the paucity of evidence for the historic presence of lynx? Current guidelines from the International Union for the Conservation of Nature (IUCN) on translocations (a term that is used to include any movement of species from one place to another) says that the method is an “effective conservation tool”, including for reintroductions within the species’ “indigenous range”. The idea of the ‘indigenous range’ is based upon historic records but, as we’ve just seen, this is a particularly fuzzy concept in Ireland – records can be ambiguous, incomplete or even misleading.

The natural range of a species has, in any case, never been something that is fixed but rather is a fluid space – species move around all the time, expanding and contracting their ranges, not only due to human pressures but also following disease outbreaks, climate shifts or even tectonic movements which have created islands or joined previously isolated continents. The idea that species have, or had, a fixed, and knowable ‘indigenous’ range is increasingly recognised as a shaky concept.

How does this help us in the task of rebuilding natural ecosystems? We need to acknowledge that historic records are insightful and important, but we should also recognise that their usefulness in facing the challenges of the future has its limits.

Present-day ecologists have no choice but to fill in the gaps, not in an arbitrary way, but using the ecological knowledge that exists about how ecosystems work.

So, for instance, we know that top predators play an essential role in regulating ecosystems and we know that lynx do this job in many European countries which share – broadly speaking – Ireland’s climate and biodiversity communities. In this light, the fact that the historical record for lynx in Ireland is poor becomes substantially less relevant.

The IUCN guidelines allow for introductions of species and “assisted colonisation” outside of the indigenous range, something which can include “the intentional movement and release of an organism outside its indigenous range to perform a specific ecological function”, something which could apply to any of the missing top predators in Ireland, or other species such as beaver, which is helping to restoring river systems across Europe although for which there is no evidence that it was ever present in Ireland.

This approach is not a willy-nilly invitation to release any and all species to Ireland. The IUCN is clear that any translocation must be subject to rigorous risk assessment and warns of the added risk of doing this outside the known range of the species. But equally, we have to stop using the historic record as the one and only arbiter of whether a species should or shouldn’t be introduced.

Ireland has not deliberately reintroduced a species for conservation purposes since the trio of birds of prey in the 2000s (golden eagle, white-tailed eagle and red kite). Across the water, the UK House of Commons has recently set up a special committee to examine the issue of species reintroductions. India is reintroducing cheetahs, the US state of Colorado is bringing back wolves, France has been reintroducing bears to its Pyrenees region, Argentina is translocating jaguars.

And it’s not just large, flamboyant species, the IUCN has detailed over 400 translocation projects since 2008 from around the world, many are plants, insects or fish. They are helping to repair damaged ecosystems, restore resilience and abundance in the face of climate stress and reconnecting people with nature. They are also overwhelmingly successful. It’s a task we need to be getting on with in Ireland.

Pádraic Fogarty

The ‘Origins of Ireland’s Biodiversity’ conference is due to take place at Fota Wildlife Park in Cork in September and promises to throw new light on the on-going story of Ireland’s wildlife. See https://www.fotawildlife.ie/news/origins-of-irelands-biodiversity-a-scientific-meeting-to-address-issues-relating-to-post-glacial-colonisation-of-ireland/