Around The Web
Drum lines were set in the wake of the attack on Ben Gerring and a 4.2m-long great white was caught shortly afterwards
Western Australia’s fisheries department has trapped and killed a large great white shark in baited drum lines close to the site where a surfer suffered life-threatening injuries in an attack.
The authorities took samples from the 4.2m-long shark to see whether it was responsible for the attack which left a 29-year-old fly-in fly-out worker, Ben Gerring, fighting for his life.Continue reading...
You’ve probably never heard of them, let alone seen them, but it’s likely you have some in your home. Springtails are only 1-2 mm long but are ubiquitous, found in every habitat except the oceans.
Springtails are closely related to insects – they have six legs and a head, thorax and abdomen – but are not insects because they lack wings and have soft bodies and hidden mouthparts. Springtails are known scientifically as Collembola.
Collembola are unique in carrying a jumping organ beneath the abdomen, held in place with hooks. When released, the jumping organ springs free, hitting the ground and forcing the animal to leap into the air, hence their common name.
In the wild, springtails can be found in leaf litter, soil, under bark, in sand, under stones, in tree canopies and even in caves and ant and termite nests. In termite nests they may control fungal growth. Most importantly, springtails have been shown to be useful bioindicators of environmental change.
Some male springtails perform a complex mating dance to attract the female. Other species are carried by insects for dispersal or feeding purposes.A springtail mating dance as shown in David Attenborough’s Life in the Undergrowth.
In Australia, there are several thousand species, most found only in this country. In any garden compost heap there will be millions of individuals belonging to about ten species. Native springtails may be brightly coloured and patterned; white, if living in soil; or black if living in exposed habitats such as mountain tops, beaches or coral reefs.Native springtails can be brightly coloured - this is Acanthanura from Tasmania. Copyright Andy Murray Another Tasmanian springtail, Temeritus. Copyright Andy Murray Springtails in the home
Three species are commonly found inside buildings, all with an elongated bodies and belonging to the family Entomobryidae. These are introduced species, which were probably brought to Australia in soil and animal fodder before quarantine controls were put in place.
If you put sticky or water traps in a garage or shed, for instance, after only a day or two springtails should appear floating on the water or trapped in the glue. You might have to use a magnifying glass to see them.
Cellars invariably harbour several species. One unusual example was in a doctor’s surgery, where every morning springtails were found floating in the then-cooled water of the steriliser, having emerged overnight from their hiding place and fallen in.This Entomobrya springtail is from the family often found in homes. Andy Murray/Flickr, CC BY-SA
Springtails are dispersed involuntarily in several ways. They can be transported in air currents and in flowing water in drains, as well as being carried in timber, packing materials and footwear, by domestic animals and on fresh vegetables and house plants. Species on vegetables could only become established in pot plant soil.
Household springtails feed on fungi and other microorganisms, which can be present in clean, relatively dry habitats such as within walls and under floors.
One species of springtail is sometimes found in baths and basins, having crawled up drain pipes. This species is most commonly observed in summer when conditions outside are particularly hot and dry, but cooler, moister conditions exist indoors.
Springtails only very rarely become a nuisance, not because they cause allergies or bite, but because they sometimes become extremely numerous in domestic situations. The few records of springtails being found on the human body have almost all been shown to be a case of mistaken identity.
If springtails become too numerous in a house, it is best to use normal cleaning methods, such as vacuuming carpets and sweeping floors to reduce populations. But if the source population is in walls or under floors, this won’t work.
Chemical methods may not be successful as, on the whole, these animals are resistant to pesticides. Instead, the source of the population should be found, which could be pot plant soil, adjacent garden soil, or debris under the floor, and the habitat cleaned out.
Domestic springtails are harmless to us and do not carry diseases. In the natural environment they are considered “goodies” as they are detritivores and contribute to nutrient cycling by breaking down organic matter by grazing on microorganisms on dead leaves and in logs.
In the home, therefore, springtails are not to be feared. In the wild, they play a valuable ecological role and many species are colourful and have intriguing habits.
Penelope Greenslade does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond the academic appointment above.
Sugarcane waste, drones, solar-powered alumina refining and strata-owned solar: which Arena R&D projects could make a big difference to Australia’s energy sector?
Although there are numerous innovative projects seeking to improve the sustainability of Australia’s energy sector, one of the main barriers to making them happen is – as with most things – money.
With the Australian Renewable Energy Agency (Arena) set to lose $1.3bn in unallocated funds, the agency has announced a raft of grants for green projects, including $17m for nine research and development projects that “have a pathway to being fully commercial” through industry partners.Continue reading...
The killing of tourist Cindy Waldron by a saltwater crocodile while swimming north of Cairns on Sunday has reignited the debate about how to keep people safe from crocs. Federal MP Bob Katter has called for a bigger crocodile cull, although the Queensland government has once again ruled this out. There are very good reasons for this decision.
The evidence suggests that calls for complete deregulation of croc hunting are based on flawed arguments. The easiest way to keep people safe is to make sure they understand the risks.What have we been doing about crocodiles?
Crocodile populations have been managed in northern Australia since the early 1970s. Before that, it was open season: three decades of hunting wiped out 95% of wild crocodiles, although getting them all proved impossible.
Many hunters grew to respect these unequivocally Australian “beasts”, supporting their subsequent protection. Yet their numbers bounced back much faster than anyone expected. Questions were soon being asked about the wisdom of allowing their recovery.Sub-adult saltwater crocodile basking on a tidal mud bank, a popular sight for the many tourists who visit northern Australia each year. Adam Britton
Recognising the value of crocodiles to people and ecosystem health, the Northern Territory government changed tack. Crocs became tourism icons, their eggs and skins were harvested sustainably to create local jobs and a fledgling industry, and safety issues were managed by the targeted removal of “problem” crocodiles, alongside visible media campaigns about staying safe. Despite differences between states and territory, the same basic approach is still used.
Has it been effective in saving lives? The first subsequent recorded fatal attack in Queensland happened in 1975, when Peter Reimers was killed while wading in a creek near Mission River. This was only a year after the crocodile population had been protected because it was on the verge of disappearing. Three decades of unregulated hunting hadn’t saved Reimers' life.
The latest statistics as compiled by CrocBITE show 112 attacks between 1971 and May 2016, 33 (30%) of them fatal. That’s an average of 2.5 non-fatal attacks per year and 0.7 fatal attacks per year across Western Australia, the Northern Territory and Queensland. The rate has increased slightly over the past decade, but crocodile attacks remain extremely rare in Australia.Number of reported saltwater crocodile attacks per country (April 2007 to April 2014). Fatal proportion in red, percentage shows fatality rate. Adam Britton / CrocBITE
The average size of crocodiles is increasing as the population continues to mature towards full recovery. However, given the very low number of attacks, it’s difficult to assess if this has had any impact on the fatality rate.
Attacks usually happen because people get in the water with crocodiles. Such an obvious cause should be easy to prevent, and indeed this is the case.
Attack risk in Australia is low, largely because of the success of long-running campaigns to warn people of the dangers of swimming in crocodile-populated waters.What lurks beneath? If you’re in crocodile habitat and you find water, always assume that it harbours a crocodile. Adam Britton
Those who live locally are generally most keenly aware of the dangers. Sadly, a disproportionate number of attack victims are visitors who aren’t as aware of the risks. The real problem can therefore be interpreted as a failure to communicate risk, and therein lies the solution.How to not get eaten by a crocodile
Crocodile attacks are traumatic, unfortunate and potentially tragic incidents that generally can be avoided. Australia has an excellent track record in saving people from crocodile attack. Despite having more saltwater crocodiles than any other country, we have low fatality rates because our management and education program is world-class.
Other countries with crocodiles come to Australia for advice on how to manage their crocodile populations and prevent conflict with people.
But there’s still a grey area for many people. How do you know whether it’s safe to swim in northern Australia? What’s the risk of doing so?
We make decisions every day to assess risk, whether we’re driving, walking down the street, swimming in a pool, or taking a boat out on the water. We’ve been trained to minimise the risks we face.
The same is true of going into the bush and facing potential dangers from snakes, mosquitoes or other animals. Sometimes accidents will happen, often because someone decided to push their luck.Distribution of saltwater crocodiles throughout their range, including northern Australia. Green are viable populations, orange are recently extirpated populations and blue represents their potential for movement within and between countries. Brandon Sideleau / CrocBITE
But with crocodiles the rules are simple: don’t enter the water in crocodile habitat. In these areas, stay away from the water’s edge, don’t disturb water consistently in the same place, don’t approach or tease crocodiles, camp at least 50 metres from the bank, and don’t go out in small, unstable boats.
Warning signs about crocodiles are there for a reason, to allow you to make an informed decision about your personal safety. Ignore them and you may get away with it, but eventually you will not.The name ‘saltwater crocodile’ is misleading. They are equally at home in freshwater habitats. Adam Britton
There’s little doubt that Australia knows how to manage wild crocodile populations. The risk of being attacked by a crocodile here is vanishingly small because crocs and people are managed effectively.
We already have a limited cull of crocodiles; the targeting and removal of specific animals that, through their actions, pose an elevated risk to the public. A wider cull won’t gain anything, at the cost of local livelihoods and our natural resources.
This article was co-authored by Erin Britton, a biologist at Big Gecko Crocodilian Research in Darwin.
Adam Britton received funding from Charles Darwin University to develop the technology for the CrocBITE database.
Report from US Geological Survey says northern wildfires must now be seen as significant driver of climate change, not just a side-effect
The devastating rise in Alaska’s wildfires is making global warming even worse than scientists expected, US government researchers said on Wednesday.
The sharp spike in Alaska’s wildfires, where more than 5 million acres burned last year, are destroying a main buffer against climate change: the carbon-rich boreal forests, tundra and permafrost that have served as an enormous carbon sink.Continue reading...
Last year saw record worldwide investment and implementation of clean energy such as wind, solar and hydropower
An upsurge in new wind, solar and hydro plants and capacity saw renewable energy smash global records last year, according to a report on new supply.
Some 147 Gigawatts of renewable electricity came online in 2015 - the largest annual increase ever and as much as Africa’s entire power generating capacity.Continue reading...
Pressure mounts on ministers to release full evidence behind the decision to end mandatory use of a harmful chemical sheep dip
MPs are demanding that ministers release key documents and correspondence connected to the decision to end the mandatory use of a chemical sheep dip by farmers.
The call comes as the government made a partial release of evidence to explain why it ended use of the chemical. The documents, published for the first time, show ministers were advised to end use of the chemical because of its failure to eradicate the disease (sheep scab) caused by the parasite.Continue reading...
Mexico, Canada and US collaborate on report that concludes the three nations will have to dramatically ramp up efforts to reach 10% protection goal
North America is far from reaching national and international targets for protecting oceans, according to a first-of-its-kind report released on Wednesday.
The Dare to Be Deep report, created by a coalition of NGOs in the US, Canada and Mexico, finds that less than 1% of these countries’ oceans are protected like national parks – with only four years left to reach the 10% protection goal set in the multilateral Biodiversity Convention.Continue reading...
Brexit would allow Britain to renegotiate a more favourable share of catches, claims out campaigner George Eustice
Britain would have an opportunity to upend fishing quotas that give a “disproportionately large” share of catches to France if it votes to leaves the EU, according to George Eustice, the pro-Brexit minister for farms, food and fisheries.
In an interview with the Guardian, Eustice said that even if it left the EU, the UK would still respect catch limits set out to preserve stocks, some driven to near-extinction by decades of over-fishing.Continue reading...
We asked you to share your most striking images of the weather in May from around the world. Here are some of our favourites
• You can add your June weather photographs here
Funding for geoengineering computational experiments was mysteriously included in a Senate appropriations bill
On his late-night talk show, Jimmy Kimmel recently invited climate scientists to explain that they’re not just messing with us about global warming.Continue reading...
Elephant populations in Tanzania’s Selous national park could collapse unless poaching and mining are urgently controlled, say WWF
Elephants could disappear from one of Africa’s most important wildlife reserves within six years unless industrial scale poaching is stopped and mining is brought under control, the WWF has said.
Selous national park, a world heritage site in southern Tanzania, has lost an average of almost 2,500 elephants a year since the 1970s. But it has now reached a crtitical stage with only about 15,000 left, according to the latest census.Continue reading...