Thursday, 5 February 2015

Batting For Australia

 What an amazing service bats do for this nation and what little thanks they get for it! Most of us are familiar with larger bats, the flying foxes, as we can witness their spectacular flight formations over the Sydney sky at dusk.  These animals provide vital ecological services. They are important pollinators (the sole pollinators of certain tree species) and they also disperse seeds which helps keep our forests viable. Their natural diet is native fruit and pollen.
 What you may not know is that we also have nearly twenty species of microbat in our area.  Most of these are very small...some are as tiny as your thumbnail and weigh less than a 10 cent coin!  Most microbats eat only insects and some thrive on mosquitoes - scoffing down thousands every night.  In fact, if bats ever became extinct, insect numbers would soon reach plague proportions (they already save us billions of dollars a year in agricultural pest control). So why do humans get so illogically squeamish at the very thought of these cute and beneficial creatures?  Well many people wrongly associate bats with vampires, witchcraft and black magic but the only spells I’ve seen them cast in real life are those of wonder and fascination.  Bats are warm blooded, placental mammals.  Like us, they usually have one baby at a time, with occasional twins. They carry their offspring around with them for about three weeks after they are born, and continue to breast-feed them for up to 6 months. Although flying foxes have good sight and all bats can see with their eyes, the really amazing thing about microbats  is that they fly and hunt in darkness using echolocation.  They basically emit ultra sonic calls and by repeatedly scanning the echoing sound patterns, can mentally construct an accurate image of the environment in which they are moving as well as their potential prey. No wonder they have such big ears!
 Until recently there was a colony of around 22,000 Grey-headed flying foxes roosting in the Royal Botanical Gardens. It became quite a tourist attraction as it was possible to observe the chattering, upside-down hanging, melee during daylight hours.  Unfortunately, the Botanical Gardens Trust decided that the bats were causing too much collateral damage to their exotic trees and with Federal Government approval, moved them on, using loud recorded noises. Grey-headed flying foxes are a threatened species, protected under both state and national environment law. Thankfully, it seems, many of the relocating bats have been welcomed by the Centennial Parklands Foundation and small colonies have even made themselves at home on the Peninsula. It is recommended that people do not disturb or handle bats though, as, like all animals, including cats, they can carry disease.

Endangered Grey-headed flying foxes roost near a busy road at Balgowlah

 Microbats roost inside tree hollows and sometimes under rock overhangs, bridges and culverts during the day.  Their main threat is loss of habitat and competition for roosts from Indian Miners and feral bees. They are also at risk from predation by cats and rats and are sensitive to pollution, loud noise and bright lights.

Footnote: Amazingly, our part of the world can even boast a bat that fishes....the Large-footed Myotis.  It forages over pools of water in rivers, lakes and small streams, using its over-sized feet to scoop along water surfaces for small fish and aquatic insects. It has recently been found at Narrabeen Lagoon.

A Lesser long-eared bat

People in "the know" believe that bats are the coolest animals on the planet. To find out more and to help with conservation efforts check this link.. Sydney's bats

Saturday, 3 January 2015

Beautiful Sydney has such an ugly secret.

  In scenic Sydney we’re lucky to have quite a few patches of “urban bushland”  dotted  around the traps that have been mercifully spared from the bulldozers.

Unblemished  Sydney bushland
 The sad truth though, is that most of these remnants are being smothered by introduced invasive weeds, used as convenient dumpsites and are fast losing their (once) amazing biodiversity.

This ancient Banksia has been smothered to death by introduced weeds
 Just look along the fence lines of properties backing onto bushland and you’ll discover, almost universally, the same story, a total disconnection from and lack of respect for the natural vegetation. Sydney homeowners invariably seem to grow plant species that “escape” from their gardens into the bush (such as Agapanthus) and “out compete” the fragile natives. They also turn a blind eye to (and neglect to tackle) destructive weeds such as Morning Glory, Lantana, Ginger Lily and Privet that thrive on the fertilizers washed out of their flower beds.
Ginger Lily, Fishbone Fern and Morning Glory will totally replace fragile native plants.
 To compound this problem they tend to think that it’s their god given right to hurl garden clippings, unwanted bricks and scrap metal into the bush, providing species of unwanted weeds from around the globe, a perfect springboard to assault our fragile native flora.

Almost everyone grows this same boring weed species called Agapanthus

 The upshot is that Sydney bushland, far from being the richly diverse “larder” that sustained indigenous peoples for millennia, or the wondrous spectacle that would have greeted Captain Cook and his crew, is fast disappearing before our very eyes.

A typical Sydney fenceline..the yellow (Senna) and blue (Morning Glory) are strangling the bushland.
  Worryingly, virtually no one living next to bushland appears to have any knowledge of what’s happening,  very few are inclined to retain or grow endemic native plants on their land, are bothered to remove weed species or express concern at the disturbing rate of land degradation (apart from isolated “Bushcare” groups).

 Indeed, almost the only interaction between residents and bushland is the increasingly popular practice of poisoning surviving Eucalyptus trees to enhance views. Some people also have a habit of moving into bushland suburbs for the natural beauty values only to then complain about the fire risks and lobby for greater “hazard reduction” zones.

 There is an incredible amount of ignorance in the community about native flora and fauna, so most residents would fail to distinguish between native plants and the introduced species that are fast replacing them. If the trend continues, our natural areas will just become one big weedy desert. As a consequence the birds, animals and insects that relay on native plants for their food source, will vanish too.

When native plants disappear, so does most biodiversity
 So what’s the solution?  Residents whose houses back onto bushland, should be encouraged to learn more about their “duty of care”, prompted to remove invasive plants species from their gardens and fined for doing the “wrong thing”. Councils and government should be much more proactive in regards to community education (as should our schools). According to the Australian Conservation Foundation,  people today recognise less than 10 plant species but more than a thousand corporate logos.

Australia these days is populated by people from around the world. Not surprisingly, most have little understanding or awareness of this nation’s natural heritage and many have an unnatural fear of this continent’s nature. I believe new citizens should have to learn not just about the nation’s history but about its natural history.

 It doesn’t help that TV “gardening”  shows totally ignore the plants that grow naturally in this country and concentrate on promoting only exotic hybrids and cultivars. Who is going to protest the loss of something that the community doesn’t even realise is going? The reality is that it would take a massive capital expenditure to substantially and professionally restore areas of degraded bushland plus a political will that just doesn’t exist ( most current rehabilitation programs are small scale and cosmetic).

Gardening "experts" will never tell you about native Beronias!

 The trouble is, once you possess the knowledge that urban bushland is in deep crisis, a walk in your local reserve will never be quite the joyful experience that it once was.

 In a society that puts such a high premium on beauty and good looks...where did it all go so horribly wrong?

Fancy a walk amongst the weeds??

 Check out this other blog post if you are interested in  "Re-wilding" your backyard

A few community members have seen the light and are caring for
remnant bushland.

Weed better talk about this issue...

 Believe me, for most of my life I thought weed was either something you smoked or kicked sand in the face of. If you’d told me years ago that I would develop a malevolent dislike for the plural of weed, I would have thought you were off your trolley, barmy, nuts, crazy, absolutely stark raving, stonking mad. But then I suppose I went “troppo”, ended up living in the suburbs of Sydney, and discovered the awful harm these pernicious things actually did.  To be fair, I was raised in the English Midlands where weeds were harmlessly insignificant and there was so little genuine nature left, that they were almost as good as it got.  I’ve since learned that around 80% of Britain’s flora is not endemic. 
 Fast forward to life in the burgeoning metropolis of Sydney, which is still blessed to have pockets of native vegetation interspersed with suburbia. Here you’ll find incredible plant biodiversity and species that have survived from the time of the Gondwana super-continent, learning to adapt and evolve to dry, hot, arid conditions and nutrient poor soils and fire. You’ll also find lots and lots of weeds. These are not weedy weeds though...they’re aggressive super-sized marauders on a testosterone fueled rampage.  And yes, like just about everything else that’s bad in this wonderful continent...the ignorant, thoughtless, careless colonialists and their progeny are to blame.

 It all started with the first British settlers wanting to plant reminders of “home” at every given opportunity and it continues to this day with the horticultural industry still bringing in new profit-making varieties from overseas. Every single one is a potential weed.

Weed management  actually costs the Australian economy around $4 billion annually,  weeds represent, the second greatest threat to biodiversity after land clearing and almost half of Australia's 220 declared noxious weeds were introduced deliberately, one third of these as garden ornamentals.  

  People still prefer to plant “exotics” rather than their own native species and chances are these will invade the bushland and outgrow, overwhelm and displace the flora that was there originally, especially when boosted by the steroid effect of high nutrients provided by garden fertilizers and urban run-off.  If you love nature, it is pretty hard to witness the demise of high diversity bushland as it gets swamped, smothered and eventually killed off by a suite of foreign invaders. These are some of the most prominent rogue species on Sydney’s Northern Beaches. If they exist in your garden, please get rid!

Asparagus Fern.  This menace is from South Africa and like many other weeds..its seeds are spread by birds that eat the red berries.  You can offer see this as a feature plant in suburban gardens, especially in hanging baskets.

Lantana. This native of Central and South America was brought to Australia in around 1840 as a garden ornamental. It has now invaded around 4 million hectares and graziers spend over 17 million dollars per annum trying to control it.  (NB in heavily denuded areas it is often the last refuge for small birds so caution is advised before hurried removal). Lantana has been cultivated for well over 300 years and has hundreds of hybrids. It has been nominated as among the top hundred world’s worst invaders. It is thought that the original un-hybridised version no longer exists in nature.
Cotoneaster. This is another weed from China which is highly invasive.  It is a common garden plant which escapes into the bush and also acts as a food source for feral bird species.
Senna/Cassia  This is another nasty piece of work from South America which was imported here as a garden plant..It is very invasive and thrives in all conditions.
Morning Glory This is another ostensibly “pretty” garden plant but once it gets into the bush it can be a nightmare to remove. A native of China, it was used for medicinal purposes due to the laxative properties of its seeds.
Ochna is a native of South Africa with bright yellow flowers. It is also known as the Mickey Mouse Bush due to the plant’s red sepals and black seed which has a passing resemblance to the Disney character. Another rampant invader of our bushland.

Privet. As a child in Birmingham UK, we had massive privet hedges in our garden which were sculpted and lovingly preened. Little did I know that in later years I would be frantically cutting these plants down. In Australia, their black fruits are greedily consumed by birds which collaborate in spreading this pest deep into fragile bushland where it grows rampantly. There are small-leaf and broad-leaf varieties native to Eastern Asia and European privet which is native to Southern Europe and Northern Africa.
Pittosporum Undulatum (Sweet Pittosporum). This is a weird one as it is actually a native plant that has gone feral and is now out-competing other species and shading them out. It has done especially well in soils that have been modified by humans and takes advantage of high nutrient levels.

For help identifying weeds of the Sydney region click here  weed I.D.

Friday, 10 October 2014

Welcome Home "Diggers"

 Great news for conservationists (and conversationalists)! Two “lost” species are returning to our suburbs. The Long-nosed Bandicoot, a once common resident (but not seen in Manly Vale for 45 years) is amazingly, making a comeback. And the Brush-turkey..a rare visitor to Sydney in the last 20 years or so, is now strutting up and down my street (and many others) with “gay abandon”.

 Bandicoots, it seems, have benefited from targeted fox baiting and their numbers are bouncing back, as the population of this introduced predator is curtailed.  Brush (or Scrub) Turkeys, which were virtually wiped out by hunting and loss of habitat (apparently their tough and stringy meat provided many a family feed during the Great Depression) are also reclaiming their territory.

 Of course these great examples of wildlife resilience has stimulated a cacophony of criticism. Some churlish people baulk at the small v shaped holes that bandicoots make in lawns when looking for grubs...whilst the fact that Brush-turkeys build large nesting mounds doesn’t win them many fans (especially with the “English style” manicured garden brigade). The irony is , these “protected species”, vilified by some for their habitual digging, are benefiting us all by doing just that !

 A recent Murdoch University study has found that native digging animals (also including Bilbies,Potaroos etc) play a key role in promoting eco-system health. Their activities increase soil nutrition, seed dispersal and water infiltration.  Some foraging animals are also credited with reducing bush-fire risks by taking leaf litter underground. The diggings of feral species such as rabbits, in contrast, promote the spread of weeds and have a negative effect on the soil.

 Imagine how our landscape might have looked if we hadn’t systematically eradicated most of our native wildlife! (Australia has the world’s worst record for mammal extinction in the last 200 years). So please, embrace these lovely “diggers” give them some space, keep your pets away and make the wildlife feel at home!

Long -nosed Bandicoot (Perameles nasuta)

 A  nocturnal marsupial with large pointed ears and a long muzzle.  It is greyish brown in colour with a creamy white forefeet and under-body.
Habitat: Rainforests, woodlands, heathland, grasslands.
Distribution: from Vic to Qld borders.
Size: 310-425mm
Lifespan: around 2.5 years
Diet: Omniverous. Primarily beetles, ants, larvae, fungi, roots, shoots.
Breeds: July to March
Gestation: only 12.5 days (shortest of any mammal)
Litter: 1 to 5.  In a good year, females may produce up to 4 litters.
Predators: dogs, cats, foxes (and cars)
 An “isolated” population of around 200 can be found at Manly’s North Head and is listed as “endangered”.

Sadly, many Bandicoots fall prey to domestic cats (photo James Taylor)

Australia Brush-turkey (Alectura lathami)

One of three Australian “Mound Builders”- the other two being the mallee fowl and the orange-footed scrubfowl. It has deep black plumage, bare red head and neck, a broad flat fan tail. Males have a redder head and neck and a distinguishing yellow “wattle”. A chick looks similar to a quail and has brown feathers.
Habitat:  Rainforest and eucalypt forest
Distribution:  Australia’s east coast from NSW to Queensland
Size: 60-70cm body length.
Lifespan: 10 years
Diet: Leaf litter, invertebrates and fruits
Breeding:  Occurs from August to January. The male brush-turkey builds a large mound of organic matter up to 6 metres wide and 1.5 metres high. The females are attracted to a well built and maintained mound and one or more birds will lay eggs inside it. The decomposition of the vegetation inside the mound produces heat The male checks the temperature by inserting his bill and then adds or removes material to maintain a 32to 33 C degree temperature. After around 50 days the young brush-turkeys hatch and have to fend for themselves.
Female brush-turkeys lay between 20 and 30 eggs a year. (one mound may contain up to 150 eggs over a season)
Predators: Goannas, snakes, birds of prey, foxes, domestic cats and dogs. To protect themselves, brush-turkeys form roosting groups in trees.

And here's a view of a Bandicoot visiting my own Manly Vale backyard (after many years of endeavouring to create the right habitat for them!)  

Thursday, 8 May 2014

There's a Mermaid hiding in our creek!

 Each successive modern generation is growing up in world that has less biodiversity and beauty than the one before. As a consequence the sense of loss at what is disappearing becomes diminished. Nowadays polluted creeks and lack of biodiversity have become the norm, a far cry from when the traditional Aboriginal owners were custodians of this land.

 It’s amazing to think that in suburban Sydney just a mere seventy years ago...platypus still occupied some of our creeks and streams. That was before most of the waterways were piped or sullied by storm-water drains and leaking sewage infrastructure. If we could suddenly turn back time to how the area used to be, then more people would realise the ugly truth of what our “civilisation” has done.

Just some of the junk removed from Manly Creek one Clean Up Australia Day
 Of course many of these creeks are now hidden away and choked by invasive weeds and discarded rubbish.  Incredibly though, some ancient denizens still cling to life in their murky waters, much like they have done for a large chunk of eternity.

 On Manly Creek, in the Northern part of Sydney, there is a place called Mermaid Pool (named after the young girls who used to bathe there in the Great Depression).  But a local native fish expert, Andrew Lo, insists that the real Mermaids are the fish themselves...and it’s hard to argue with his logic.

 Andrew was the guy who discovered that an amazing fish, which breathes through its skin and climbs up sheer rock faces, lives within the Manly Dam catchment area (in the upper sections of Manly creek-line).  This Climbing Galaxias population is the most northerly in Australia. It’s a living Gondwanan relic, but its clean-stream habitat is very vulnerable.   Members of the community once celebrated its birthday with a special 60 millionth birthday cake, a symbolic gesture during a protest blockade against development of its habitat. This area has since become a housing estate and one of the Galaxias’ creeks and bushland surrounds was ultimately bulldozed and concreted to make way for “progress”. Read  more about the Climbing Galaxias on the Australian Museum website.

 Back down the creek towards Manly’s surfing beaches you can still spot a number of other “Mermaids” which still migrate to spawn up this waterway just as they’ve always done...and they somehow still do it, despite the golf course dams, the pollution incidents, the choking exotic weeds, the irregular water flows, the algal blooms, the feral fish predators and the general lack of knowledge of their existence and consequently, any regard for their well-being..

 These are some of the native fish in question:-

 Jolly tail. The common galaxias spawns downstream in rivers and streams amongst vegetation on the banks of the estuary regions during a spring tide mainly in autumn. The eggs remain on the bank (out of the water) until the next spring tide when they hatch into larvae which are swept out to the ocean. For the next 5–6 months the larvae live in the sea and develop into juvenile fish, often referred to as whitebait.

The Striped Gudgeon is best recognised in the wild by the five to seven dark stripes on the sides of the body, and a dark stripe running posteriorly from the eye.
Andrew finds a tiny juvenile Striped Gudgeon during a survey

 Cox’s Gudgeon. Juveniles are able to climb waterfalls by rotating their pectoral fins so that the inside surfaces of the fins are pressed against the wall creating suction. 

Juvenile Cox's Gudgeon climbing a sheer rockface
Empire Gudgeon. Females are brown to golden and whitish below. In the breeding season males become bright orange-rea on the head and belly. The dorsal and anal fins become bright red-orange basally and with a dark sub-marginal stripe and lighter margins.

Australian Bass are an iconic, highly predatory native fish.Longevity is a survival strategy to ensure that most adults participate in at least one exceptional spawning and recruitment event, which are often linked to unusually wet 'La NiƱa' years and may only occur every one or two decades.

This Australian Bass was caught and released
The Bullrout should be handled with extreme care. The dorsal, anal and pelvic spines all have venom glands. A puncture wound from one of these spines can be excruciatingly painful.

The Flathead Gudgeon is primarily found on muddy bottoms, often amongst vegetation. The species occurs in freshwaters, but is also recorded from estuarine and protected areas in coastal bays. (There is also a Dwarf Flathead Gudgeon).

Firetail Gudgeon. This is a small native Australian fish that occurs in freshwater coastal streams. The body is generally grey to bronze with black scale margins. During the breeding season males can be almost black, with intense red-orange fins.

Firetail and Cox's Gudgeon

 Longfinned eel. Female eels can have millions of eggs in the ovaries. Developing leptocephali take about one year to return to the streams of eastern Australia. Glass eels arrive in New South Wales in early Summer. Those that make the additional journey south to Victoria arrive from January to late May. Young eels (called elvers) then swim upstream and spend a number of years maturing in freshwater.

Shortfinned eel. When they reach maturity, they stop feeding and migrate downstream to the sea, then anything up to three or four thousand kilometres to a spawning ground in deep water somewhere in the Coral Sea off New Caledonia.

Native fish migrate from the sea via Manly Lagoon up Manly Creek to breed.
In 2001 there was a herbicide spill near here from a local golf course which killed many thousands of fish. Manly Lagoon is rated as one of the most polluted waterways in Australia