Outdoor cats are a contentious issue for cat-owners, cat-lovers, and those that are concerned about the environment. Like it or not, Fluffy is doing a LOT of damage (Image credit: Cat Outside in Sweden-148884.jpg by Jonatan Svensson Glad, CC BY-SA 4.0, Image Cropped).
Tag Archives: extinction
Modeling the ecology and evolution of biodiversity: Biogeographical cradles, museums, and graves (2018) Rangel et al., Science, 244, DOI: 10.1126/science.aar5452
Understanding the processes which drive biodiversity worldwide is never more crucial than now, in a world where biodiversity is shrinking rapidly. Biogeography, the study of species distributions, has come a long way, but there are still a lot of problems that need solving, including improving our understanding of the interactions between factors like climate change, dispersal abilities, fragmentation and species competition, to name a few.
This paper attempted to analyse some of the effects of those factors in concert, by producing a simulation of the evolutionary process in the world’s most biologically diverse continent, South America.
Estimating interaction credit for trophic rewilding in tropical forests (2018) Marjakangas, E.-L. et al., Philosophical Transactions of the Royal Society of Biology, 373, https://dx.doi/10.1098/rstb.2017.0435
We have reviewed more than enough papers on biodiversity loss to entitle us to skip the whole “losing species is bad” spiel (see here, here and here). But what we haven’t talked about is that when some species are lost, specific interactions that those species participate in disappear from an ecosystem. Those interactions range from the minute to the crucial. One such crucial example is that of seed dispersal, whereby specific plants rely on specific animals to disperse their seeds, thus maximising biodiversity in other parts of the forest and creating a positive feedback loop.
Naturally, conservationists will want to reintroduce animals to propagate some of these reactions. But as is always the case in conservation, maximising return is absolutely essential when you’re faced with limited resources and a lot of ground to cover. Today’s authors wanted to develop a system for maximising the effect of species reintroduction.
A release of the formerly endangered Running River Rainbowfish. So how were they brought back from near-extinction? (Image Credit: Karl Moy, University of Canberra, CC BY-SA 4.0, Image Cropped)
We talk a lot about getting the public interested in conservation and ecosystems on Ecology for the Masses, but we’ve rarely talked about how conserving a species is actually accomplished. Where does funding come from? How do you decide which individuals to save? And how do you allow a population room to grow?
In 2015, Peter Unmack was sampling in the Burdekin river system in northern Queensland, Australia, when he noticed an alien population of Eastern Rainbowfish had established in Running River. Specifically a 13km stretch bounded by two gorges, which housed the Running River Rainbowfish, a species distinct to this one stretch. Knowing that the presence of the Eastern Rainbowfish could spell the extinction of the local species, he started a crowdfunding initiative, and essentially saved the Running River Rainbowfish. I spoke to Peter and postgraduate student Karl Moy about the conservation effort.
Sudan, the last male northern white rhino, 3 years before he passed away, rendering the species functionally extinct. But should species like this be the focus of our conservation efforts? (Image Credit: Make it Kenya, Public Domain Mark 1.0, Image Cropped)
Last year saw the death of Sudan, the last known northern white rhinoceros in the world. The story went viral, with the usual bemoaning of the way humans treat our planet, followed shortly by the normal rush back into anonymity for the world’s biodiversity. We are currently part of the most dramatic mass extinction event that the planet has ever seen, and more of these stories crop up every year. But is it a problem that the alarm bells are only raised when a creature hits the critically endangered level? Do we need to start paying more attention to population declines before hey hit such low numbers? And how do we even prioritise conservation efforts?
Nest predation by raccoon dog Nyctereutes procyonoides in the archipelago of Northern Sweden (2018) Dahl & Åhlen, Biological Invasions, https://doi.org/10.1007/s10530-018-1855-4
We’ve spoken about biological invasions at length on EcolMass, and the detrimental effects that the arrival of a new species can have on native populations. Yet eradication is often impossible, and management expensive, so before taking extensive action, it’s always important to ensure that an alien species IS having a negative effect.
The raccoon dog is an Asian species, closely related to foxes, that was introduced to Europe in the early 20th century and has since spread into Scandinavia. Voracious predators that could spread further north due to climate change, our paper this week looks at the extent of their impact on the ecosystems they’ve spread to.
Biological annihilation via the ongoing sixth mass extinction signaled by vertebrate population losses and declines (2017) Ceballos et al., Proceedings of the National Academy of Sciences of the USA, DOI: https://doi.org/10.1073/pnas.1704949114
Guest Post by Jonatan Marquez
The rate at which species and populations have been going extinct in the last couple of centuries has well and truly earned the title of the planet’s sixth mass extinction event. However, most people rarely realize the severity of the situation. Hearing about the loss of two vertebrate species a year or having the last of some far-off species die out doesn’t see to cause much concern in the general public.
A species extinction is always preceded by population declines and extinctions. Perhaps highlighting the state of natural communities at this level might put the severity of the situation in better context. For example, the Living Planet Index (LPI) estimates that between 1970 and 2012, wildlife abundance has decreased by 58%. This paper focuses on the state and trends of populations of vertebrates by analysing i) the proportion undergoing declines or shrinkages, ii) the global distribution of population reduction events and iii) the general scale of population declines among mammal populations.