More than just drains: recreating living streams through the suburbs



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A drain carries water but does little else, but imagine how different the neighbourhood would be if the drain could be transformed into a living stream.
Zoe Myers, Author provided

Zoe Myers, University of Western Australia

Lot sizes and backyards are shrinking in Australia at the same time as building density is increasing. So we cannot afford to overlook the potential of existing – but neglected – spaces in our suburbs, like drains.

In denser living environments, we will need new types of green and open space to meet the needs of residents.

One such overlooked space is the urban water drainage system. As part of my research I’m examining the potential of a co-ordinated and integrated network of suburban streams.


Further reading: If planners understand it’s cool to green cities, what’s stopping them?


The largest water catchment in the Perth metropolitan area is Bayswater Brook (previously called the Bayswater Main Drain). Largely for the purpose of improving water quality, in recent years work has begun to remake drains running through the suburbs into “living streams”.

Aside from the obvious benefits of water purification and stormwater management, these networks of suburban streams can be re-imagined as preferred paths through the neighbourhood.

Using established drainage routes capitalises on their existing connections through a suburb. This network could amplify the connections between parks and other green areas, providing a rich soundscape of birds, frogs and insects, and a diversity of sedges, rushes, melaleucas and other vegetation along the banks.

Look at the big picture

While the conversion of old infrastructure into living streams is not new, it has as-yet-unrealised potential to rehabilitate the large sections of open drainage that run in visible, connected ways through our suburbs. This elevates the idea of a living stream to a multi-layered ecosystem, one that includes multiple drains across the suburb.

The Bayswater Brook permanent drainage system runs through the northeastern suburbs of Perth. These drains can be dangerous and public entry to these areas is prohibited out of necessity.

Access barriers are unsightly but necessary because the existing drains can be dangerous.
Author’s own

The drains run along the rear of mostly low-density housing, hidden from streets.

An aerial view of houses backing onto a 90-metre long open drain in Perth.
Google Earth

Their condition is typically marked by weeds, minimal vegetation and stagnant water.

Fenced-off areas offer no public benefits to the neighbourhood other than drainage.
Zoe Myers, Author provided

The sheer number of these open drains across the metropolitan area offers a compelling opportunity to reconceptualise the system as a holistic and integrated network of ecologically restored streams. This requires co-operation between multiple levels of government.

A project by WaterCorp in Western Australia (which manages drainage infrastructure) has begun inviting local governments to submit proposals for use of the green space around drains. These are currently for small portions of the larger network, such as a pop-up park planned for a basin in Morley.

The benefit of doing this in a co-ordinated way – rather than single stream restoration – lies in the possibilities of making these spaces a genuine alternative to the street.

What are the benefits?

Typical drains (above and below) add very little to neighbourhood amenity.
Zoe Myers, Author provided

Zoe Myers, Author provided

By activating unused, off-limits areas at the back of houses, we can turn public space “inside out”. Providing a sequence of accessible paths creates a new option for pedestrians away from roads and cars, but still with an established, clear route through the suburb. We can have a space that is buffered from traffic noise without the isolation of an empty park segregated from main thoroughfares.

Many studies have convincingly found connections between the sounds of waterscapes and restorative emotional states and views. Having multiple entry and exit points as the streams thread through the suburbs would heighten the spaces’ usefulness as everyday pathways. Children could walk along the streams to school, or adults could take a short cut to catch the bus to work, maximising this kind of beneficial interaction with water.

Recreating natural habitats would also increase biodiversity and create a multi-sensory environment, as well as a cooler micro-climate. That would make it an even more attractive place to be in hot months. Encouraging a more natural flow of water through the streams would also reduce biting midges and mosquitoes, which thrive in stagnant water.


Further reading: Green for wellbeing – science tells us how to design urban spaces that heal us


Potentially the most convincing reason for local governments to rehabilitate drains is that living streams increase neighbourhood property values. Research has shown the effect is significant. In the Perth suburb of Lynwood, for example, median home values within 200 metres of a wetland
restoration site increased by A$17,000 to A$26,000 above
the trend increase for the area.

This in turn can support increased density. High quality nature spaces potentially offset the sacrifice of the usual backyard area, by increasing the number of people with direct access to these spaces.

Turning an urban drain into a living stream opens up a world of possibilities.
Author’s original render

The ConversationThere is a growing imperative to remove the false choice between designing for people or for nature. Remaking our old infrastructure for many new uses offers multiple benefits to our ecology and well-being. When a drain becomes a living stream it doesn’t just provide a new kind of open space but adds a new dimension to enjoying, and moving through, your suburb.

Zoe Myers, Research Associate, Australian Urban Design Research Centre, University of Western Australia

This article was originally published on The Conversation. Read the original article.

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Like alchemists with killer precision, brown snakes make different venoms across their lifetime


Timothy N. W. Jackson, University of Melbourne

It’s spring in Australia and that means reptiles are starting to move about again. Including snakes.

The venom of the eastern brown snake (Pseudonaja textilis) is, drop for drop, one of the most potent of any venoms tested on laboratory mice.

Venoms work by targeting the bitten animal with deadly chemicals. And our recent research shows toxins in the venom of eastern brown snakes change as the snakes grow from juveniles to adults. It’s the first example of a significant age-related change in venom from an Australian snake.

It’s a beautiful example of evolutionary adaption, in which the chemistry of the snake’s venom appears to change in parallel with its diet.


Read more: Why I love surrounding myself with venomous critters


What is snake venom?

Venoms are typically a mixture of different toxins, each of which attacks the system of a potential prey animal or predator in a different way.

Sometimes toxins work together, each making the other more powerful, and sometimes they work completely independently, engaging in chemical warfare on multiple fronts.

Brown snake venom contains many toxins, but there is one toxin above all others that is responsible for the life-threatening effects of bites to humans. This toxin is a “haemotoxin”, which means it attacks the blood.

The haemotoxin starts clotting the blood at an extremely elevated rate, using up all of the coagulation factors, which clot the blood under normal circumstances. When all these are used up, the victim is at risk of bleeding to death.

In the worst case scenario this toxin, perhaps working with others, gives the system such a shock that people collapse within a short period of time following the bite. In this situation, immediate CPR can be the difference between life and death.

Why venom evolved

Venom is a tool that has evolved in snakes to help them secure a meal: it gives them a chance of overpowering animals that would otherwise be very difficult for them to subdue. Venom and its toxins are therefore “designed” (by evolution) to mess up the normal operations of a prey animal’s body.


Read more: Curious Kids: how do snakes make an sssssss sound?


The best toxins for this purpose may differ according to the specific type of prey animal (e.g. mammal or reptile), or the condition of that prey animal (e.g. whether it is active or inactive) when the snake finds it. As a result, we often find snakes that feed upon different types of animals have different toxins in their venoms.

This starts to get really interesting when you consider brown snakes, because adult brown snakes seem to have quite different diets from baby brown snakes.

Testing a venom hypothesis

Age-related shifts in venom chemistry have already been demonstrated for the venoms of a few species of pit vipers from the Americas, but not for anything even remotely related to Australian brown snakes.

This wasn’t because people hadn’t looked – several species of Australian snake had been investigated, but no evidence of a significant age-related change in venom had been found for any of them. This made sense to me, because none of those snakes dramatically change their diets throughout their lives.

Brown snakes are special – as far as we know the juveniles eat lizards almost exclusively, whereas the adults are generalists that eat a lot of mammals.

Baby snake venom is different

When we compared venom in adult and baby brown snakes, we did indeed find them to be different. Baby brown snake venom seems to entirely lack haemotoxins: instead, it’s almost exclusively composed of neurotoxins – toxins that attack nerve junctions.

What this suggests is that the haemotoxins that are so dangerous to humans (and lab mice) aren’t very effective against the lizards that baby brown snakes eat. We can make this dietary link with a degree of confidence because many other Australian snakes that feed exclusively on lizards have similar venom – no haemotoxins, only neurotoxins.


Read more: Snakebites are rarer than you think, but if you collapse CPR can save your life


We don’t yet know what this means from a clinical perspective. It may be that baby brown snake venom is less dangerous to humans than adult brown snake venom, but the opposite might also be true – brown snake antivenom might be less effective against the venom of the babies.

There has been at least one fatal bite from a very small brown snake in Australia, so they must be treated with respect at any age.

The ConversationAs always, the best policy for snakes is to leave them alone and let them go about their business, and to teach children to do the same – snakes want no more to do with us than we want with them.

Timothy N. W. Jackson, Postdoctoral Research Fellow, Australian Venom Research Unit, University of Melbourne

This article was originally published on The Conversation. Read the original article.

Curious Kids: What happens if a venomous snake bites another snake of the same species?



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Scientists usually use the word “venomous” rather than “poisonous” when they’re talking about snakes.
Flickr/Sirenz Lorraine, CC BY

Jamie Seymour, James Cook University

This is an article from Curious Kids, a series for children. The Conversation is asking kids to send in questions they’d like an expert to answer. All questions are welcome – serious, weird or wacky!


If a lethally poisonous snake bites another lethally poisonous snake of the same species does the bitten snake suffer healthwise or die? – Ella, age 10, Wagga Wagga.


Hi Ella,

That’s a great question.

If a venomous snake is bitten by another venomous snake of the same species, (for example during a fight or mating), then it will not be affected.

However, if a snake is bitten by a venomous snake of another species, it probably will be affected.

This is probably because snakes have evolved to be immune to venom from their own species, because bites from mates or rivals of the same species probably happen fairly often.

But a snake being regularly bitten by another snake from a different species? It’s unlikely that would happen very often, so snakes haven’t really had a chance to develop immunity to venom from other species.


Read more: Guam’s forests are being slowly killed off – by a snake


Scientists often collect venom from snakes to create anti-venoms.
Kalyan Varma/Wikimedia

Snakes can break down venom in the stomach

Many people believe that snakes are immune to their own venom so that they don’t get harmed when eating an animal it has just injected full of venom.

But in fact, they don’t need to be immune. Scientists have found that special digestive chemicals in the stomachs of most vertebrates (animals with backbones) break down snake venom very quickly. So the snake’s stomach can quickly deal with the venom in the animal it just ate before it has a chance to harm the snake.

People that have snakes as pets often see this. If one venomous snake bites a mouse and injects venom into it, for example, you can then feed that same dead mouse to another snake. The second snake won’t die.


Read more: Curious Kids: How do snakes make an ‘sssssss’ sound with their tongue poking out?


The eastern brown snake, which is found in Australia, is one of the most venomous snakes in the world.
Flickr/Justin Otto, CC BY

The difference between venom and poison

By the way, scientists usually use the word “venomous” rather than “poisonous” when they’re talking about snakes. Many people often mix those words up. Poisons need to be ingested or swallowed to be dangerous, while venoms need to be injected via a bite or a sting.

Some snakes can inject their toxins into their prey, which makes them venomous. However, there seem to be a couple of snake species that eat frogs and can store the toxins from the frogs in their body. This makes them poisonous if the snake’s body is eaten. Over time, many other animals will have learned that it is not safe to eat those snakes, so this trick helps keep them safe.


Hello, curious kids! Have you got a question you’d like an expert to answer? Ask an adult to send your question to us. You can:

* Email your question to curiouskids@theconversation.edu.au

* Tell us on Twitter by tagging @ConversationEDU with the hashtag #curiouskids, or

* Tell us on Facebook


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The ConversationPlease tell us your name, age and which city you live in. You can send an audio recording of your question too, if you want. Send as many questions as you like! We won’t be able to answer every question but we will do our best.

Jamie Seymour, Associate Professor, James Cook University

This article was originally published on The Conversation. Read the original article.

Nicaragua: Indio Maiz Biological Reserve – Illegal Beef Farming


The link below is to an article reporting on illegal beef farming in the Indio Maiz Biological Reserve in Nicaragua.

For more visit:
https://news.mongabay.com/2017/09/nicaraguan-beef-raised-illegally-in-biological-reserve-mostly-exported/