Whilst climate change continues to hog the limelight, habitat loss remains the key threat to biodiversity worldwide. And whilst events like the Australian bushfires obviously contribute to habitat loss, its main cause is land clearing, whether for agriculture, cattle grazing, mining or urbanization. No matter how many politicians deny or try to deviate attention from it, scientists have shown time and time again just how threatening habitat loss is to our planet’s biodiversity.
On the surface, the process seems quite simple. Habitat goes away, animals lose shelter and food. Yet this is just the tip of the iceberg. Many processes take place below the surface, cascading through an ecosystem. So let’s have a look at the manifold effects of habitat loss, and why it’s the greatest threat to biodiversity today.
Image Credit: Bert Knottenbeld, CC BY-SA 2.0, Image Cropped
In case you’ve been living under a rock (in which case, stay there, there’s probably less smoke), you’ll know by now that Australia has experienced wildfires over the last couple of months that dwarf what California and the Amazon went through last year.
The Australian bush fires have been widely covered in the media, but let’s do a quick summary of the stats^. Earlier this week, approximately 73,000 square kilometres – around the size of Belgium and the Netherlands combined – have been burnt and over a billion mammals, birds and reptiles have likely been killed. Tragically, 24 people have died as of Monday, three of whom were volunteer firefighters.
So how has the nation – and the world – reacted? The spectrum has been vast, making analysing the reaction no easy task. So today I wanted to have a look at Australia’s (and in a sense the world’s) ongoing reaction to the Australian bushfires as per the Kubler-Ross Five Stages of Grief.
The Cataract Gorge in Launceston, Tasmania, where the 2019 Ecological Society of Australia Annual Meeting was held (Image Credit: Marina Schmoeller, CC BY 2.0)
I just got back from 10 days in Tasmania, Australia. As a temporary visitor in the country, I extended my trip to attend the Ecological Society of Australia’s annual conference (ESAus) as much as I could, so I could explore the surroundings and get to know a little of the place, its people and its unique biodiversity.
The conference was held in Launceston, the second largest city in Tasmania. With about ninety thousand inhabitants, a rich history with deep roots in its eye-catching landscapes, the Tamar River Valley and the Cataract Gorge, Launceston is a charming place with a lot to offer all visitors. But let’s talk about the conference.
Image Credit: Swallowtail Grass Seeds, Public Domain Mark 1.0, Image Cropped
There has been a lot of recent (and well deserved) press surrounding the bush fires in Australia. Because of these fires countless animal and plant life has been lost, and the most visible example of that are the koalas. You probably saw the video of a woman running into a burning area to save a koala from the fire*. Unfortunately, most of the koalas didn’t have people around to save them and over 1,000 are estimated to have died. Because of this a group has claimed that koalas are now “functionally extinct”, and the press has run with this claim. While it is unfortunate that this misinformation spread so quickly and so widely, the good news is that koalas are in fact NOT functionally extinct. Great! But what does being “functionally extinct” mean?
Eating beef isn’t great for the environment. But can someone who occasionally snacks on cows still be in favour of conservation and other ecological causes? (Image Credit: Gellinger, Pixabay licence, Image Cropped)
Today I want to talk about a tweet. Or more accurately, the attitude to sustainability that this tweet represents. It occurred during the recent Ecological Society of Australia conference, and went roughly thus*.
Good to see only vegetarian food at ESA2018. We know that it’s not possible to be truly in support of conservation unless you cut meat out of your diet.
Now for starters, I want to make it clear that I am 100% in support of eating vegetarian. For those of us fortunate enough to be living in relative affluence, vegetarian diets are easy to maintain, generally cheaper (based on personal experience), and have a proven positive impact on the climate. I’m not completely vegetarian, but I take a lot of steps to minimise my diet’s climate footprint. It doesn’t take much.
The European Perch, brought for angling by earlier settlers, has had severe effects on a number of native Australian fish (Image Credit: Karelj)
Transport pathways shape the biogeography of alien freshwater fishes in Australia (2018) Garcia-Diaz et al., Biodiversity Research, DOI: 10.1111/ddi.12777
Invasive species are a problem in every type of ecosystem, be it by reduction of local diversity, or negative effects on a region’s economy or human health. Freshwater rivers and lakes are no exceptions to this. Invasive fish have impacts on local habitats which include outcompeting or just flat out eating local species, changing a habitat’s entire structure (say by clearing away aquatic vegetation or increasing pH levels) and the reorganisation of the entire population of a lake or river, from the birds that nest on the shoreline to the tiny planktonic species that are the base food source of the entire ecosystem. Once an invasive species is established, it can be impossible to remove.
So naturally, understanding where and how invasive species are likely to strike is of huge benefit. This paper tries to map that out, using Australia as a case study. It’s a great example; Australia has a long history with invasive species, and this study alone looks at 33 different types of invasive fish.