Conservation strategies have been historically focused on getting an overview of the species in a region, and then trying to protect those species that are endangered. I’ve written often before about how important a top predator species can be to the overall health and biodiversity of an ecosystem. For example, the presence of wolves in a natural region can impact the health of the forest and even river flow.
But like reading the ingredient list for a familiar recipe, we’ve worked on the assumption that carrying out a tally of individual species in a certain area and getting a consistent count usually means that the biodiversity is also remaining the same and will result in the same ecosphere profile.
If a major ingredient is missing or in decline, we work to protect it; if a ‘wrong’ ingredient has been introduced in the form of an invasive species, we work to push it back out. The goal has been to prevent a major loss of biodiversity.
But what if the entire ingredient list is shifting, forming a completely new recipe on the page, even as the number of ingredients remains the same?
A study out in Science shows that around the world, monitoring programs are showing a surprising consistency of biodiversity – but only when it comes to the absolute number of species counted. The composition of the species is an entirely different matter: In some coral reef regions, the number of coral species has dropped significantly, even as the number of algae species has increased. Florida has a wide diversity of species – when it comes to non-native ants.
According to authors Nicholas Gotelli and Robert Colwell, as habitat ranges shift under the influence of climate change, some areas might see an increase in nominal biodiversity, but it will be at the cost of traditionally local species in favor of successful ‘generalists’ like invasive weeds, rats or ants.
The study concludes that there “is need to expand the focus of research and planning from biodiversity loss to biodiversity change.”
The change is happening quickly, over just a decade or even a year. A bit like putting a cake in the oven, and then when the timer goes off, opening the door to find instead a casserole.