The Journey Of Native Seedlings Beginning At Our SPAs

With inputs from Angela S., hobby botanist, database lead and volunteer at the Wetlands Centre.

The thriving native plant life is what makes our wetlands places of immense beauty and wonder. Their roots nourish the land and help with nutrient recycling and removal of toxins.  Their lush cover provides shelter and habitat for our wildlife. 

They add so much character to the wetlands, reflecting seasonal changes like wetland moods – flowering, and shedding. These plants have evolved to adapt to the cyclical nature of wetlands so well, coping in ever-varying conditions of dryness, wetness, salinity or freshness. And if you observe the wetlands you will catch their different tones. 

It is incredible to imagine that these plants start their life as tiny seedlings that then grow into sturdy saplings and mature plants. We, at The Wetlands Centre, do our bit in helping our native plants flourish – by ascertaining the best times to collect seeds and factors for maintaining genetic diversity, collecting seeds, storing and cataloguing seeds, propagating seeds, potting on seedlings, and then planting and rehabilitating the bushland and wetland with native plants.

We work hand-in-hand with our team of volunteers, community members, and our primary sponsors – The City of Cockburn, who are keen supporters of our work. Our established wet and dry Seed Propagation Areas or SPAs and our fully equipped “Norm’s Nursery” is where the magic happens. We’ve been maintaining detailed records of all our efforts in a comprehensive database that is proving to be very helpful in our endeavours. All the collected data can be analysed for some fascinating trends and interesting insights. 

In this blog post, we offer you a tour of our SPAs and nursery, as well as our seed store and database. While we’re expanding our knowledgebase, we are eager to learn and incorporate from your experience. We hope you’ll be able to join us in our effort to preserve, conserve and rehabilitate our precious wetlands. 

 

Collecting and Storing Seeds

It takes special knowhow to collect seeds from native plants. Some seeds are incredibly toxic, like the bright red seeds from the Zamia, and collecting them can be tricky. A whole bucket of Banksia seedpods may produce just 10 seeds (or fewer) while, Juncus and Lobelia are more prolific and only one teaspoon worth of seeds may produce over 20,000 plants!

Norm Godfrey, a wetland visionary, was a pioneer in this science. We, till date, use the list that he compiled of what seeds are best collected when. For this and for his enormous love for the wetlands we have named our water-wise garden – “Norm’s Garden” and our nursery – “Norm’s Nursery”, in his loving memory.

We collect seeds from the bushland and wetland, and we involve volunteers in all tasks, including seed collection. The collected seeds are then catalogued and stored. They are sorted by the year of their collection when they are stored. We have seeds going back to the years 2002/2003 in our seed store!

 

The SPAs and Norm’s Nursery

The centre has one wet and one dry seed propagation area (or SPA). It is here that the seeds are propagated and transplanted. We use a handy (unofficial) zone guide to determine and pick the zones. 

Norm’s nursery is a little haven for our native plants. There are 139 native plants that are officially confirmed as local to our area (there may be more that are not confirmed yet) and we grow all of these. We currently have a maximum holding capacity of up to 22,000 plants!

The City of Cockburn is our primary sponsor and most generous supporter. We grow native plants for them that they then use to rehabilitate predetermined areas. Over and above this we also use the plants to rehabilitate areas within our precinct, such as Horse Paddock Swamp. We often announce our planting day events in advance and are joined by many involved and enthusiastic members of the community.

   

Our Comprehensive Database

Our comprehensive database is the cornerstone of our management efforts. We use the database to maintain records of all our seed collection, propagation, germination, transplanting and planting activities. 

We can use the database to extract specific insights – about the timelines for the various phases of seed propagation and if these coincided with any major weather events, about the yield for each batch and if there were factors contributing to an especially high/low yield, about the best methods and techniques for growing native plants, and about the amount of seed that will give us acceptable returns in terms of plant maturation. 

The database is also helping us make our operations more economical. For example, we now understand the quantity of seeds that we need to sow for the output we require, and we are not over-sowing or over-producing. We are also gathering information on seed viability and the various factors that affect plant health. For example, we were able to keep records of how much sodium bicarbonate we added per watering can and eventually worked out the best amount to bring liverwort and other mosses under control in the nursery. 

We are assimilating this information, gathering context and improving our processes continuously. This makes management a little more scientific, precise and predictable. 

 

Planting and Propagation Events

In our 26 years of landcare, education and conservation work, we have built a considerable knowledgebase. We are learning more and more about the behaviours of our native plants and the best ways of supporting them.

We are interested in sharing all the knowledge we have collected and we welcome groups and individuals to contribute, assist and partake. There is so much to learn and do together!

If you’re interested in what we do and want to help us in our efforts, come join us as a vollie. We will be delighted to have you. Optionally, you can join us for general landcare work on Thursdays and Fridays. 

No formal qualification or working knowledge of plants is required to volunteer.  Just an open mind and a willingness to learn and embrace new stuff. There are a range of diverse and interesting activities to indulge in. And our friendly team of staff and vollies will make it up to you with laughter, fun, a warm cuppa and lots of bikkies.

We encourage you to visit us or have a chat with us at The Wetlands Centre Cockburn – about how you can participate and help your local wetlands!

All About A Backyard Frog Pond

The cacophonous and often noisy sounds of our Aussie amphibians – from the revving of the motorbike frogs to the strum of the banjo frogs and the grumpy wails of the moaning frogs, make our wetlands come alive! Little do we realise that the presence of these critters is an important sign of the good health of our wetlands.

We are blessed with a unique frog diversity with over 200 frog species calling Australia their home. Alarmingly, more and more of them are dwindling and now over 43 of them have been documented to be critically endangered and 3 seemingly extinct. Everything from human activity, urbanisation, urban encroachment and habitat loss, pollution and litter, clearing and draining of wetlands, and introduction of toxic chemicals, pesticides and fertilizers, is affecting them.

By building a frog pond in your backyard you are ensuring that these happy hoppers get a chance to beat the odds and survive. Plus, a healthy frog pond means that all is well with your garden. They will keep pests and insects in check by feeding on them. The frog pond will go a long way in enhancing the beauty of your otherwise ordinary backyard, and in bringing the lively sounds of the wetlands a little bit closer to home.

Our frogs spend more time in the bushland and return to the wetland to breed. If you can’t have a frog pond, a native garden, native plants, logs, mulch etc. will support them too!

Few caveats to begin with

Although frogs appear to be hardy, native frogs can be sensitive to their environment. Here are a few considerations to make while keeping our new friends:

  1. Frogs can be extremely noisy. Consider this before beginning construction. You may also want to talk to your neighbours and adjust the location of your frog pond accordingly.
  2. Do not use pesticides, fertilizers or other strong chemicals. These may impact your frogs’ food source.
  3. Avoid using exotic, non-native and invasive plants, such as amazon frogbit and water hyacinth, in and around the frog pond. Instead, use native species that the frogs love.
  4. Avoid adding “exotic” fish to your frog pond as these can predate on frogs, especially tadpoles and eggs. However, it may be beneficial to include some native fish, such as the Western Pygmy Perch or the Swan River Goby, as they are non-invasive as well as help in controlling mosquitoes by feeding on their larvae.
  5. Frog ponds may attract snakes, skinks and other reptiles. It is best to practice caution and be aware of these creatures’ presence while accessing the backyard. Consider covering the pond top with mesh or wire-fencing the pond to safeguard children.

 

Construction of your frog pond

Frogs need ample moisture, adequate food and some shelter. Consider these aspects while designing and constructing your frog pond. The pond itself doesn’t need to be very large for these tiny critters to feel safe and sheltered.

Sunlight is an important consideration to make. Without enough sunlight the tadpoles may not metamorphose in a season. So, the placement of your pond should be such that it receives a good amount of sunlight and some shade. Choose a location with about 70% shade and 30% sun. (And, a one-third sun during winters and a dappled sun during the summer months.)

For materials, everything from concrete to fibreglass works and pre-cast or prefabricated ponds are available in shops. Although it is essential to get PVC and UV stabilised liners for these.

Creating a comfortable home

To create a comfortable home for our frog friends, place gravel, rocks and logs in and around the pond. Frogs are ectothermic and rely on the external environment to control their body temperature i.e. if it’s cold they will try and find a sunny spot to bask and if it’s sweltering hot, they will then find a cool shady spot to relax. Make sure that variations of sunny and shady spots are available to them around their habitat throughout the year.

Ensure the walls of your pond are not too steep or slippery, as some frogs can get stuck and drown in the water. The pond must have sloping sides for frogs to easily navigate and manoeuvre around as well as move in and out of the pond. Fashion ramps made of wood or plastic or collect rocks and pebbles around the edges. If gardens are attached to the bush and attract bobtails, they too need these exit ramps to avoid falling in and drowning.

Fringing and aquatic vegetation is essential to their survival. A leaf litter and algae often safeguard tadpoles and fringing vegetation provides shelter and habitat for frogs. Use rushes, sedges, hostas and ferns to create an enclosed and safe habitat.

Attracting frogs to your pond

Once you have built your perfect pond, it may still take a while for it to become well-established and for froggies to come find it. Don’t be disheartened. Have patience!

It is important that you don’t import frogs from elsewhere into your pond, rather wait for local native species to find it. This is an important step in preserving the genetic integrity of the local gene pool. The local motorbike frogs can smell water from a great distance and will be the first ones to arrive.

Note that catching tadpoles or frogs from local water sources is illegal!

There is a local tadpole exchange program happening through the Western Australian Museum. Also, the national “Frogs Australia Network” database can be an invaluable resource while finding resident frogs through their tadpole exchange program. And, heaps of useful information on frogs and frog calls can be found here.

Should the frogs still be hesitant in arriving, here are a few tips for making your frog pond more attractive to the shy critters:

  1. Avoid keeping the pond too clean and tidy. Preserve the natural rustic state of the pond along with healthy leaf litter and organic matter. Insects and other organisms will thrive in such an environment and so will the frogs that in turn feed off them.
  2. Skip any fountains, filtration systems or waterfalls that you may want to add. Frogs like quiet, still and undisturbed waters.
  3. Create damp and cool crooks and crannies and wet areas around the pond. Use terracotta pots and planters, bricks, dead logs, driftwood, pebbles and stones, mulch and other materials. Frogs will often hide and take shelter in these spots you create.

 

Frog Pond at Norm’s Garden at The Wetlands Centre

If you’re seeking inspiration for your own frog pond or are simply looking for a spot to observe the happy hoppers in action, Norm’s Garden at The Wetlands Centre Cockburn may be perfect for you.

Norm’s garden is a water-wise garden developed using sustainable gardening practices and named after “Norm Godfrey”, a wetland visionary and poet.

Our frog pond is overflowing with tiny critters that aren’t too shy to make some noise on a good day. Or, come down to the Centre for our frog night stalk where we uncover the delightfully raucous sounds of frogs calling through the dense cover of the night.

 

References

  1. Black, D. (2019). The Amphibian Research Centre at Frogs.org.au. Retrieved 20 August 2019, from https://frogs.org.au/
  2. My Backyard » Frogs. (2019). Mybackyard.info. Retrieved 21 August 2019, from http://mybackyard.info/backyardblog/?cat=4
  3. Ponds, B. (2008). Backyard Frog Ponds. GARDENING AUSTRALIA. Retrieved 21 August 2019, from https://www.abc.net.au/gardening/factsheets/backyard-frog-ponds/9428752
  4. Frog bog and pond basics | Sustainable Gardening Australia. (2019). Sustainable Gardening Australia. Retrieved 23 August 2019, from https://www.sgaonline.org.au/frog-ponds/
  5. Oz Watergardens – the know-how on frog pond design. (2019). Ozwatergardens.com.au. Retrieved 23 August, from http://www.ozwatergardens.com.au/frog-ponds
  6. Frogs – Natural Resources Adelaide and Mount Lofty Ranges. (2019). Naturalresources.sa.gov.au. Retrieved 3 September 2019, from https://www.naturalresources.sa.gov.au/adelaidemtloftyranges/plants-and-animals/native-plants-animals-and-biodiversity/native-animals/frogs

Our Wetlands In A Changing Climate

As ecosystems that thrive on so little, our wetlands are delicate. Yet they are abundant sources of water in this growingly water-starved world. They are carbon sinks, that remove and trap over 13% of the world’s carbon. They are biodiversity hot-spots where some of the most beautiful and unique species live and flourish.

While we are fortunate to still see wetlands around us, their survival is threatened. They are exhibiting what the scientists are calling a ‘distress syndrome’, wherein, their functional capacity has been radically impaired. Their plant and animal distributions have been drastically altered. And there are several disturbances, induced stresses and a range of pressures that are making their fragile ecosystems imbalanced.

Image of a starving polar bear on a melting ice sheet

Much of this has been the result of climate change. A topic that is heavily discussed but less understood in the context of wetland conservation and rehabilitation. It is only gradually becoming clear that climate change impacts each wetland in a specific and unpredictable way. And it is through constant monitoring, research, on-ground work and active participation that some of the impacts can be stalled or even reversed.

Our conservation efforts at Bibra Lake and North Lake, within the Beeliar Regional Park, have been remarkable. Through the course of our work, we are constantly learning about the nature of our wetlands, their many unseen facets and how they respond to a steadily shifting environment.

In this article, we draw a sketch of the strengths and weaknesses of our dynamic Beeliar Wetlands as they stand the test of a changing climate. And what it will take for them to survive this massive global event.

Understanding climate change

Climate change is perhaps the greatest issue confronting us today!  As greenhouse emissions continue to rise it is predicted that global temperatures could increase anywhere between 1-5 degrees in the 21st century.


This video from NASA’s Climate Change website, highlights global temperature anomalies. 2018 and 2017 were the fourth and second hottest years respectively since modern record-keeping began in 1880. NASA and NOAA work together to track the temperatures, part of ongoing research into our warming planet.

Major atmospheric changes drive hydrological changes. So, global warming at that scale can lead to prolonged droughts in some areas and pronounced precipitation in others. Hydrological changes further drive hydrogeological changes affecting groundwater recharge and water purity. These changes themselves are enough to degrade some wetlands considerably.

The continuing rise in temperatures also threatens species who depend on the wetlands for survival. Waterfowl are susceptible to changes in temperature and precipitation. For migratory birds, the climate affects their habitats as well as the migration corridors. For other species whose breeding cycles are tied closely to the climatic conditions, the rise in temperatures makes the situation unfavourable.

Climate change has a range of other impacts on the wetlands themselves, their ability to recycle and process nutrients, how they absorb and trap carbon and process sediments to generate soil. These activities further impact the distribution of flora and fauna, favouring some over the other. Invasive species thrive and change wetland ecology, damaging habitat and food source.

The stresses of climate change are only heightened by human activity – urbanization and pollution.

Climate change and Beeliar Wetlands

The Beeliar Wetlands is the name given to the two chains of wetlands that run parallel to the west coast of Western Australia. While one chain of lakes is saline, the other is freshwater. The wetlands are located towards the southwest portion of metropolitan Perth within the larger Beeliar Regional Park.

The wetlands on the Swan Coastal Plain and in particular the Beeliar Wetlands are a surface expression of the underlying groundwater.  There is still much to be learnt about the effects of climate change on our wetlands.  What the data shows us is that for about the last 40 years we have been receiving less rain.

Groundwater levels have never been static, decreasing during summer and increasing when recharged with winter rain as water makes its way through the soil to groundwater.  With decreasing rainfall, the groundwater recharge has decreased and levels have dropped. Together with the decreasing recharge, there has also been incessant removal of groundwater to supplement our supply of drinking water.

In most cases, this has led to our wetlands drying out more often or for prolonged periods each year. But, bear in mind, a drying wetland is natural and it is during the drying times that those intrepid birds fly in from Siberia to eat the bugs out of our mud.  It’s tricky business and honestly, none of us have the whole story.

The unpredictable changes in the lakes drying and filling have also complicated our revegetation efforts.  While in general we are allowing for increased dry conditions and adjusting the zones in which we plant, on several occasions we have been caught with heavy summer and spring rain events inundating some of our plantings.  These conditions highlight the need for Adaptive Management.

It is not only the wetland and wetland vegetation that is affected by this lowering of the water table.  Many of our bushland species also depend on groundwater for survival.  This became very evident during the particularly low rainfall season of 2010-11 when many banksias higher in the landscape of our bushland died.

Changes in global climate may well be a contributing factor on groundwater levels, but healthy well-maintained wetlands can also be a key tool in our efforts to lessen the impact of climate change on other systems.

Here’s taking a closer look at the Beeliar Wetlands and how climate change has impacted some of the wetland functions.

1. Changing Hydrology:

The Beeliar Wetlands depend on seasonal rain to recharge. Over the years there have been fluctuations in the amount of precipitation. These fluctuations have caused alterations in wetland zonation, impacting the distribution of native plant species within the wetlands.

2. Loss of biodiversity:

With changing zonation, wading species and waterfowl are impacted.  Constant encroachment has led to a serious habitat loss, loss of fringing vegetation and bushland. This has further impacted species such as turtles, frogs, snakes and lizards many of which are endangered.

3. Carbon loss:

With many of the wetlands now experiencing a dry spell and terrestrialisation, the carbon trapped within the soils is released back into the atmosphere. And there is a further loss in capacity to capture and trap carbon from the atmosphere due to the growing number of dysfunctional and degraded wetlands.

Read our blog post on ‘Saving Bibra Lake’ for an in-depth examination into our conservation and rehabilitation efforts on Bibra Lake and North Lake.

Preventative measures

The wetlands are facing an incredible amount of stress from climate change alone, and we have to realize the importance of reducing additional pressures. This will give our wetlands a fighting chance to cope and replenish.

While most of us have come to accept the reality of human-caused changes in our global climate, we must also step up to the task of addressing the impacts of these changes.  There are many actions we can take locally to help our wetlands through this period.

Here are a few ways in which we as individuals and community can help:

  1. Reduce waste. Don’t litter.
  2. Conserve water. Be judicious. Click this link to check out Watercorp’s tips for saving water.
  3. Recycle and reuse to the maximum extent.
  4. Reduce your carbon footprint.
  5. Walk or cycle wherever you can. Or use public transport.
  6. Grow native plants in your garden. Go organic. Be fertilisewise!
  7. Participate in wetland activities. Volunteer with The Wetlands Centre.

Don’t forget to quack, quack, quack…  That is wetland speak for talk, talk, talk…  Pass on the message to friends and family.  Tell them about waterwise, fertilisewise and of course, volunteering.

Join The Wetlands Centre Cockburn

At ‘The Wetlands Centre Cockburn’, we are located a hop, skip and jump away from the glorious Bibra Lake, within the Beeliar Regional Park. Our proximity stirs and inspires us to work with the community to safeguard and protect this amazing yet fragile asset.

Community Planting Event at Horse Paddock Swamp in the Beeliar Wetlands

We have seen remarkable progress over the 25 years we have been around and are always looking for new helpers.  If you are not into getting down and dirty, we have education programs that need helpers too!

Combating climate change will take all our effort. Come join our forces today. Together let us maintain and improve the resilience of our wetlands so that they can continue to provide important services to us and the coming generations, even under changed climatic conditions.

Saving Bibra Lake

An aerial view of Bibra Lake on a sunny day

Cradled in the swales of the ancient dunes of the Swan Coastal Plain, and spanning over 384 hectares are the Beeliar Wetlands! They are bustling with stunning biodiversity, that include some of the most unique and fragile lifeforms on earth. Here, the calm, placid Bibra Lake stands as a timeless testament to our heritage and cultural values.

Historically, North Lake – Coolbellup and Bibra Lake – Walliabup, have served as important locations for the Aboriginal Nyoongar people. They are associated with the mythology of the ‘Waugal‘– the rainbow serpent, and Dreamtime tales of the ‘Spirit Children’.  Numerous Aboriginal campsites have been documented adjacent to the lakes. The Beeliar mob had semi-permanent camps on the land, caring for the boodja (country), precisely where the controversial Roe 8 tollway was proposed.

While we closely evaded that disaster, there are still a number of factors that continue to impact our precious wetlands. Over 90% of Perth’s once ample and abundant wetlands have been lost to agricultural pursuits, urbanisation, and development & infill. Bibra Lake and the surrounds are a reminder of what we’ve lost and what we stand to lose unless we take strong action. Together.

 

Changing wetlands in a changing climate

Our wetlands are dynamic in nature and they transform with changing seasons. Water levels in the wetlands, such as Bibra Lake, rise and fall with rainfall and the seasonal movement of groundwater. Bibra Lake experiences this seasonal flooding and drying, and oftentimes, this leads to alterations in the depth and area of the body of the lake. The transient wetlands are designed to cope, redistributing their animal and plant life in accordance with these changes.

However, with a decrease in rainfall and an increase in human activity surrounding our wetlands, the natural variations are becoming exaggerated. Causing alarming fluctuations in the wetland zonation. Introducing irreversible expansions and contractions of the wetland area.

 

Comparisson of flooded zones of Bibra Lake from 1995 to 2005
Figures depicting altered wetland zonation for Bibra Lake

Looking back, we remember the water levels of Bibra Lake during the 1980’s and 1990’s to be much higher than they are now. Many of us believe that those water levels were “proper”. However, the higher water levels of Bibra Lake at the time were actually an aberration caused by the removal of vegetative cover for the development of surrounding suburbs.

On the other hand, we also see prolonged drying of the wetlands in some years. The reduced rainfall has impacted the recharging of groundwater. And since the groundwater is also our source of drinking water for the Perth metropolitan area, this has caused a further shrinkage of the precious resource.

Bibra Lake has suffered adverse impacts. Usually, maximum water levels were seen around October and minimum levels during April. However, Bibra Lake and North Lake are now breaching these standards. This has significant implications for planting and weed control.

 

Two pictures comparing seasonal water levels of Bibra Lake
Snapshots comparing maximum and minimum seasonal water levels in Bibra Lake

A thorough understanding of these circumstances is essential towards developing a successful restoration program for Bibra Lake. We need to take the variations and on-ground conditions into account, adjusting when and where we weed and plant as we maintain and restore the lake and its surrounds.  The focus as we move forward must be on adaptive management.

We must also accept that we are moving into a period of some uncertainty, with climate change and global/local weather events becoming unpredictable. We may not get this 100% right 100% of the time. But every failure is a learning and a step forward.

 

Weeds and invasive species

Weeds are one of the most pressing problems we face at Bibra Lake, and weed control is an ongoing initiative. Often, the removal of one weed creates space for another. In some cases, it even allows the overgrowth of opportunistic native plants which can pose additional challenges. We see this most starkly in the constant balancing act of Typha control on our lakes. But that is a story for another day…

A combination of manual and chemical control along with mulching and saturation planting has been the most effective method in combating weeds. (Saturation planting is when native vegetation is planted densely and in large numbers so as to saturate and give little scope for invasive species to spread.)

At Bibra Lake, the following have been our findings:

  • Weeds must be actively growing before initiating weed control.
  • The revegetation plan should be in place prior to weed management to make the best use of the weed control efforts.
  • A monthly weed control commitment is required with a plan for the whole year.
  • At The Wetlands Centre, we have developed Seed Production Areas (SPAs) and refined propagation techniques to grow plants in our nursery.
  • The weed biomass in the seasonal zone degrades during one flooding and receding event. Slashing is sometimes required to make the area suitable for planting.
  • Mulching of the lower damp to upper seasonal zone (the weediest zone) with Typha mulch reduced the frequency of weed control.

 

Satelite images of Bibra Lake from 1953 to 2018 showing vegetation cover
Satellite images showing revegetation of Bibra Lake by The Wetlands Centre Cockburn over the years

Invasive species such as feral bees, foxes and cats are also detrimental to our wetlands. The feral cats and foxes prey on vulnerable native animals. Foxes are an introduced species and our lizards, turtles and quenda are especially susceptible since they have not developed any specific defences to stay protected.

 

Runoff and Algal Blooms

Human activity is primarily responsible for the degradation of our wetlands. Our urban developments are placed closer and closer to the wetlands, with little or no buffer. Roads and tracks crisscross the perimeter. And our wetlands are losing their lush cover, that helps protect wildlife from noise, light and other forms of pollution. All this further challenges their survival, exposing our species to danger and disease, and putting them at a risk of endangerment.

This also means that there is a greater impact on how nutrients, sediments and pollutants are naturally filtered by the wetland. The degraded quality of some of the fringing and upland vegetation around Bibra Lake is causing alterations in the water-quality of the catchment. However, Bibra Lake still fairs better than other heavily impacted lakes within the Beeliar Wetlands.

Runoff, whether it is the chemical runoff from roads or the phosphorus, potassium and nitrogen from fertilizers that we use in our gardens, leads to a nutrient explosion, and subsequently, algal blooms. The algae reduce temperature and light penetration in the catchments, suffocating and dominating over aquatic life. The algae also spread rapidly and give off an unpleasant odour as they break down. There is a direct link between the excessive use of garden and horticulture fertilizers and algal blooms in our waterways.

Reducing the use of chemicals in our gardens, keeping our storm drains clear of unwanted litter, conserving water and using it judiciously, and using landscaping practices that benefit wildlife and their habitats – every little step you take can lead to positive outcomes for our lake.

 

Join The Wetlands Centre Cockburn

At ‘The Wetlands Centre Cockburn’, we are fortunate to be located adjacent to the resplendent Bibra Lake, within the Beeliar Regional Park. This places us in an ideal position to lead by example in the care of our natural surroundings. We recognize that we bear a great responsibility to inspire, reinforce and connect, and to work with the community to safeguard and protect this amazing area.

The issues we have highlighted in this article are very real. They are threatening the health of our wonderful lake and its bountiful surrounds. We are working hard to understand and combat these issues while spreading awareness of core problems. Our team of volunteers and staff are dedicated and ever-vigilant.

In working with the land and connecting with its nurturing ways, we have come to cherish it deeply. And we want to share this connection with the greater community. Come, get involved with us. Learn. Plant. Protect. Conserve. And spread the joy.

 

This article is adapted from and based on notes and insights shared by Denise Crosbie, Wetlands Officer, The Wetlands Centre Cockburn.

Our Battle Against Weeds

A collage of weeds illustrations against a background of a weed infested field and people doing weeding work.

It is easy to be moved by the earthy and bountiful beauty of our wetlands. Carried within the constant rush is the spur of everyday life in the wetlands. From the smallest creatures to the most complex ones, all life is interwoven and interconnected. And delicate, diverse bionetworks bustle with unseen activity.

Weeds are slowly changing all we love about our wetlands. They overwhelm the ecosystems, choking and outcompeting native flora. They crowd and degrade the habitats. They spread aggressively, establish themselves stubbornly and are extremely hard to dislodge.  They hamper the myriad ecosystem functions.

In Australia, over 4 billion dollars are spent annually towards managing weeds. Costs compound when you consider the impacts from loss of biodiversity and environmental services.

Our battle against weeds is ongoing and persistent. And winning it will take a precise combination of science, engineering, ingenuity and committed on-ground support!

 

What are “Environmental” Weeds?

Environmental Weeds are unwanted invasive plants that establish themselves in natural ecosystems and permanently alter the natural processes of those ecosystems (as opposed to Agricultural/ Pastoral Weeds that thrive in agricultural and pastoral lands).

Here are a few weed facts.

  • Over two-thirds of the weeds now established in Australia originated from gardens and ponds.
  • About 10% of Western Australia’s flowering plants are introduced weeds.
  • Of the 1233 identified weed species in WA, around 800 are found in Swan Coastal Plain bioregion.

 

How Do Weeds Invade the Wetlands?

Weeds showcase resilience and they flourish in the nutrient-rich wetland environment. So much so, that weeds have established themselves in every wetland in Western Australia.

Weeds are disturbance opportunists – plants that respond positively and rapidly to changes in soil, salinity, dampness, pH and native plant distributions. So, the disturbed edges of our urban wetlands are most at risk – where roads, verges, tracks, paddocks and housing settlements, are located close to the wetlands. In these disturbed areas, conditions quickly become favourable for weed growth.

A host of activities that we humans undertake can also boost the spread of weeds in the wetlands. Urban run-off and leaching, dumping garden and pond waste, prunings and clippings, fire events such as burn-offs and arson, and overusing groundwater from bores and wells, can all have serious impacts.

 

What Effects Do Weeds Have on Wetlands?

The wetland vegetation is specialized and contributes to processes within the wetland ecosystems. And these ecosystems are delicate, often relying on natural conditions of light, salinity and dampness.

When weeds encroach our wetlands, they affect the distribution of wetland vegetation. This, in turn, has a detrimental effect on the plants and animals that depend on native vegetation for survival.

 

Weed Impact at a Glance

  1. Loss of biodiversity and simplification of wetland plant community.
  2. Impacted and altered ecosystem functions.
  3. Altered nutrient recycling.
  4. Loss of habitat and food source for wetland fauna.
  5. Increased risk of erosion.
  6. Increased fire risk, as weeds add to the fuel load.
  7. Altered soil quality.
  8. Loss of water quality.
  9. Loss of aesthetic value.
  10. Increased management costs.

 

Ways to Fight Weeds

Compared to disturbed areas, densely vegetated areas are far more resilient to weed attack. Here circumstances do not permit weeds from taking a foothold or competing successfully for nutrients, sunlight and moisture.  Thus, rehabilitating the wetland vegetation is a crucial first step towards weed control.

Restoring dryland vegetation and establishing shelterbelts around the wetlands is important too. They act as a line of defence and barrier from weed invasion.

Prevention is key. Prevent garden prunings and clippings from entering the wetlands. Similarly, prevent aquatic plants from ponds and aquariums from entering the wetland catchments. Prevent pet animals entering the wetlands, where they may graze on native plants. Pet faeces have been known to carry and spread weeds.

And finally, participate in wetland rehabilitation and conservation activities. These include weed removal, as well as planting activities, to re-establish native plants.

 

Join Our Forces!

At ‘The Wetlands Centre Cockburn’, here in the heart of the breathtaking Beeliar Regional Park, we are working towards building healthier wetlands for everyone.

We are involved in landcare, conservation and rehabilitation work. We run some exciting educational programs. We are community driven, we have a fantastic community outreach. And, we are pioneers in wetland management.

Get some action when you join us on Thursdays and Fridays. We start early, at 9am, and you can work for as long as you want until the close of day at 4pm. We have an array of weed control measures that we undertake. Or, you could participate in the nursery, where we nurture native flora.

Talk to us today and join our forces. Together let us win this fight!