large scale species' extinction
According to the 2019 report for the Intergovernmental Science-policy Platform on Biodiversity and Ecosystem Services (IPBES) (the "Paris Agreement for nature"), about 1 million species around the world face extinction because of humans, with the pace of destruction as much as 100 times faster than the natural rate over the past 10 million years, according to a global report prepared by 150 experts.[1] Those especially in danger are those that are "large, grow slowly, are habitat specialists or are carnivores - such as great apes, tropical hardwood trees, sharks and big cats”.
Changes in land and sea use by humans were the largest drivers as nature was being "altered at an unparalleled degree" with about one in eight animal and plant species facing oblivion "many within decades, unless action is taken to reduce the intensity" of those impacts.
Climate change was already emerging as a threat exacerbating other impacts, with less than 1 per cent of the former cover of coral reefs expected to survive even if the Paris climate target of limiting global warming to 2 degrees above pre-industrial levels is achieved. Relevant factors include a doubling of humanity's population in the past 50 years to 7.6 billion and a doubling of urban areas in the past quarter century. While the pace of forest loss had halved since the 1990s, the felling of species-rich tropical forests continues. Also, just a seventh of the world's wetlands in 1700 remained by 2000 and the rate of their destruction has also quickened since then.
The IPBES report noted that nature played a "critical role" is sustaining humans with food, energy, medicine and other materials. More than 75 per cent of food crops, for instance, rely on animal pollination, it said. Marine and land ecosystems were the sole sinks for manmade carbon dioxide emission, absorbing 60 per cent or some 5.6 billion tonnes of carbon a year - preventing faster atmospheric warming. To reduce humanity's impact, the Report said that incentives that favour expanding the economy over conservation or restorations should be rolled back.
Meanwhile, in November 2018, an extreme temperature event occurred in the Wet Tropics World Heritage Area which runs for 450 kilometres down the Coast between Cooktown and Townsville in North East Queensland, and includes the oldest continuously surviving tropical rainforest on Earth. It is immediately adjacent to the also threatened Great Barrier Reef. Temperatures at the top of Mount Bartle Frere exceeded 35 degrees for six days in a row, culminating in one reaching 39 whereas they usually don’t exceed 25. This has imperilled a number of the area’s most iconic and vulnerable creatures, the lemuroid ringtail possum.
This and other highly specialised possum species in the area constitute the “canary in the coal mine”, just as much as the Reef, says Kelly O’Shanassy, Chief Executive of the Australian Conservation Foundation. They show us what our future holds. “If we don’t move from burning coal to renewables in the next 10 years, we can’t stop runaway climate change and we will see this vast damage everywhere, including things we humans rely on. We lose the beauty - but we might also lose our life support systems.”
So far as NSW is concerned, the number of threatened species has risen 3% since 2016, with 1025 varieties of plants and animals deemed at risk of extinction. Some 112 ecological communities are also at risk, the main threats being habitat loss due to the clearing and degradation of native vegetation, and the spread of invasive pests and weeds. [2]
[1] This is an edited summary of the article by Peter Hannam, "Our threat to one million species", which appeared in the Sydney Morning Herald on 7 May 2019:: https://www.smh.com.au/environment/conservation/unparalleled-a-million-species-at-risk-as-humanity-s-impact-rises-20190506-p51khl.html The graphic (Source IPBES) appeared in the same article.
[2] "State of the Environment Report", cited in Peter Hannam, "NSW's threatened species rise as climate impacts increase", SMH, 10 May 2019: https://www.smh.com.au/environment/conservation/nsw-s-threatened-species-rise-climate-impacts-increase-major-report-finds-20190509-p51loh.html