Archive | January, 2013

Life Under the Port Noarlunga Jetty

21 Jan

Dear reader

This week has been hot with temperatures hovering around the mid 30s- perfect weather for a dip in the ocean. Although our urban beaches are perfect for swimming it is the more rugged coastline further south that always attracts my attention. As a keen snorkeler and underwater photographer the cliffs, headlands and rocky reefs, interspersed with fine, sandy beaches, create a tempting environment for anyone interested in marine life.

Port Noarlnga jetty showing growth of mussels and beach

Port Noarlnga jetty showing growth of mussels and beach

Consequently, last Saturday morning found me donning my summer wet suit and sliding into the water under the Port Noarlunga jetty; a favourite dive location only a 45 minute drive south of Adelaide’s CBD. Like many of South Australia’s jetties; this one is the legacy of bygone days when wooden ketches collected grain from coastal farming communities. The old wooden structure juts out from a sheltered beach and is sandwiched between low limestone cliffs and an estuary. Two hundred metres out to sea it intersects a reef that runs parallel to the shore. Although the reef is a marine sanctuary there is limited fishing allowed along the first three quarters of the jetty. Most divers go to the end of the jetty and drop straight onto the reef. However, on this occasion I had decided to swim under the jetty and look at the way the environment and marine life changes with depth and proximity to the reef.

starfish on jetty pile amongst coraline algae and green algae red

Starfish on jetty pile amongst coraline algae and green algae

 The first few metres were quite a surprise. I had expected bare sand and little life. Instead I found quite a community of organisms in the shallow warm water. Small schools of mullet and yellowfin-whiting and some bream were patrolling the sandy bottom searching for small crustaceans and worms. A few large razorfish, a fan shaped mollusc that buries its pointed end in the sand, protruded amongst the small outcrops of rock and sparse seagrass patches while several sand crabs scuttled for cover in the weed as I swam over them.

Razorfish amongst seagrass

Razorfish amongst seagrass

In the shallow zone, the jetty piles are constantly exposed to air and sun as the tides and winds vary. Only a few grey snail shells and worm tubes clung to them finding moisture and protection in the cracks in the wood. As the water became deeper a coating of small black mussels shaded the grey wood of the piles and a mixed growth of algae, sea squirts, sponges and other encrusting organisms started to appear. In the open water schools of baitfish would occasionally appear in tightly choreographed formations; a group strategy evolved for minimising successful attacks by predators. Closer to the surface, I caught sight of the occasional garfish and even a small group of squid chasing after a fisherman’s lure.

Squid in open water following lure

Squid in open water near the jetty attracted by angling lures

As I approached the end of the jetty, the character of the environment changed dramatically. The growth of invertebrates covering the wooden supports had thickened and a veritable garden of different organisms of every texture and colour imaginable competed for space and food. Small patterned fish and shrimps darted amongst these marine jungles and an occasional starfish also moved slowly though them in search of prey. The baitfish had been replaced by a mixed school of sea sweep and old wives.

School of sea sweep with a few striped old wives

School of sea sweep with a few striped old wives in the background

When I reached the end of the jetty I used the aluminium dive ladder to climb out and sat for a while on the wooden walkway and watched a few divers exploring the reef. A quick glance at my dive watch indicated that I had been in the water for well over an hour. The time had passed quickly and I had been more than pleasantly surprised by the marine life under the jetty….worth another visit.

Cheers

Baz

Baz

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Brachina’s Yellow Footed Rock Wallabies

14 Jan

Dear Reader

Today I would like to take you on a brief trip through time n one of my state’s most spectacular environments.

Hundreds of millions of years ago sediments were deposited on an ancient seabed. Over the following millennia, the sediments were compressed to form layers of rocks. In turn, the rocks were uplifted and folded creating a formidable mountain range. Eventually, the relentless action of wind, heat and water wore down the mountains and carved deep gorges through them. The result of this timeless process is the Flinders Ranges, one of the world’s oldest geological formations. Rising from the semi desert landscape some 400 Kms NE of Adelaide; they are a pleasant day’s drive through the rolling hills and open plains of the mid north’s wine and wheat districts.

Flinders Ranges emerging from arid plains as seen from the Leigh Creek Road

I have visited the Flinders many times and the rugged beauty and abundance of wildlife throughout the area never fails to impress me. However, on my most recent excursion I had a specific location and target in mind. Brachina Gorge crosses the ranges from east to west cutting through the layers of rock and revealing a unique insight into our planet’s ancient history. The 30 kms of rutted dirt track is crossed by several creeks and the geological history is traced by a series of interpretive signs. But Brachina’s rock formations are more than a glimpse into the past; they are home to one of Australia’s most beautiful marsupials-the yellow footed rock wallaby.

Layers of sedimentary rock in Brachina Gorge

Small populations of yellow footed rock wallabies (Petrogale Xanthopus) are found in rugged areas of northern South Australia. Like all wallabies they use their long tails for balance rather than locomotion. Their fur is thick especially on the feet where it provides cushioning and grip in the precipitous terrain they prefer. Yellow footed rock wallabies grow to around 60 cms in height and weigh7-13 Kgs They feed on vegetation such as grasses and forbes and sometimes graze on trees and shrubs during hard times. They are mainly active during the late afternoon and early morning.

Yellow footed rock wallaby with joey in pouch

I entered the gorge from the Leigh Creek road on the western aspect of the ranges; and slipped my SUV into high range as there had been a little rain and the track was a little tricky. The flat terrain, where the creek flows out of the hills, quickly gave way to steep sloping rock walls and bush covered hillsides that characterise the Flinders’ gorges. After a few kilometres I stopped by a shallow pool of semi permanent water where a variety of grasses and low bushes were growing along the water’s edge. A jumble of rocks had fallen from the cliff face above creating some small caves and easy access to the shallow pools of water, the perfect environment for these agile little marsupials.

Classic yellow footed rock wallaby environment

For the best part of an hour I sat amongst the vegetation, camera in hand watching and listening. The light was beginning to fade a little and I my optimism was dwindling with it. Eventually I caught sight of a slight movement high above the rock-fall as a wallaby hopped from one boulder to the other-a long shot even with the 24X lens. I shifted my position to get a better angle and to my delight and embarrassment noticed a yellow foot feeding by the creek not 5 metres from where I was crouched. It must have been there for some time and seemed oblivious or indifferent to my presence.

Yellow footed rock wallaby feeding

For the next ten minutes I watched and waited as the wallaby nibbled on the grasses and bushes surrounding the creek. I squeezed off quite a few shots and was about to call it a day when a second animal hopped onto a flattish boulder and stared pointedly at me. As I moved slightly it froze and gave me ample opportunity to capture a few more images. Sadly, I was reminded why these exquisite little animals came so close to extinction. Early settlers hunted them for their pelts and found them easy prey as their first reaction to a threat is to freeze and ironically, rely on camouflage provided by their subtly shaded fur.

Yellow footed rock wallabies showing camouflage in afternoon light

By the time I had finished photographing the wallabies, the sun was low in the sky and driving along bush tracks at night is not the safest of activities as kangaroos, emus, cattle and sheep seem to be drawn to headlights. I packed up and headed on to Wilpena an hour’s drive to the west. A sophisticated tourist development in a natural amphitheatre of towering cliffs, it would provide the perfect base to hunt for yellow footed rock wallabies in some other locations.

The track through Brachina Gorge with Wilpena in background

Cheers

Baz

Solandra Wetland’s Musk Lorikeets

4 Jan

Dear Reader

Last week, on a warm summer afternoon, I decided to walk down to the pond at the bottom of the street to photograph a pair of nesting Australian grebes. The pond is part of a chain of wetlands that feeds off the nearby creek and filters stormwater for use on local parks and gardens around Tea Tree Gully. It provides a welcome oasis for many species during the dry summer months and supports a small semi-permanent population of water birds.

Local pond

On the edge of the pond there are a few medium sized eucalyptus trees that flower this time of year. They have broad canopies adorned with either cream or coral blossoms and are a favourite destination of the local rainbow lorikeet tribe. As I passed the trees I could hear the raucous screech of feeding birds but the tone seemed a little different to the cacophony of sound that frequently greets me.  A quick glance confirmed that most of these parrots were musk lorikeets with just a smattering of rainbows amongst them.

Rainbow Lorikeet amongst white gum blossoms

Musk lorikeeets ( Glossopsitta concinna) are medium sized lorikeets between 20-30cms from head to tail. They use their brush tipped tongues to feed on pollen and nectar but will also eat some seeds, fruits and insects. They often travel in flocks and are usually found in dry woodlands where they nest in hollow branches. They are slightly smaller than rainbows and less common in this area.

Musk Lorikeet feeding on coral gum blossoms

I decided that the grebes could wait. And, while I have quite a good collection of rainbow pictures I rarely see more than a few Muskies and the chance to photograph them while feeding does not come along too often. They were endearing little animals to watch as they performed an extraordinary range of acrobatic movements. Sometimes they hung upside down to get their beaks into a bunch of blossoms; at other times they used it as a prehensile tool to climb along spindly branches. Despite their preoccupation with feeding they were still a little nervous and as I moved cautiously around the trees they scattered into the denser parts of the foliage making photography somewhat difficult.

Pair of Musk Lorikeets

I tried sitting quietly in some of the surrounding bushes closer to the pond and using the telephoto on full zoom. An equally unsuccessful manoeuvre, as the birds seemed to rarely feed on the outer blossoms as doing so would probably increase their exposure to local predators like harriers and falcons. Finally I adopted a more professional and scientific approach to the problem; walk slowly, keep shooting and hope for the best.

Musk Lorikeet pair bonding near nest hole

Dozens of frames later, with the light diminishing and more than a few bird droppings adorning my jacket, I left my flock of musk lorikeets to their meal and walked down to the pond for a quick look at the pair of grebes. One was repairing the nest and the other half hidden in the reeds at the edge. Australian Grebe building nest

Another post for another day

Cheers

Baz

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