Tuesday, 25 April 2017

 Autumn walk - Bundanoon

It's autumn now in Canberra, a good time for bush-walking as it's not too warm. So last week I went for a walk in the Morton National Park, well a tiny bit of it by the village of Bundanoon. There are various short walks through the forest there, with lookouts over the depths of the Bundanoon Creek valley.

The route I took started down the Fairy Bower Access Trail, then along the Bundanoon Creek Walking Track, down to the creek in the floor of the valley, then straight back up Tooths Lookout Walking Track. I took a few hours and walked several km, but spent a lot of time looking around, exploring and taking photographs. And I walk quickly, so this is not a guide: for details of time and length of walks in the area please refer to the Bundanoon/Morton NP website here.

The stream that forms the Fairy Bower Falls slips slowly over the cliff.

Then cascade down in two vertical drops.

Tree roots stretch down the cliff looking for soil below, somewhere.

Orange lichens grow on the south-facing walls of sandstone - the shaded aspect.

Hand-cut and placed stone steps lead down the escarpment, winding through the trees.

Autumn is mushroom season and there were several varieties of fruiting bodies. However, I do not know the species, I merely admired their colours and forms. These white ones had wonderful veils around their caps.

These white ones shone like porcelain in the deep shadow of the tree trunks they were growing on.

This sky blue gem, I have tried to identify - Entoloma virescens ?

A giant staircase led back up to the plateau, through split rocks.

And up past another split rock - one cleaved by a tree that had seeded and grown in a crack in the sandstone. Over many many years, it has opened up the crack. Just how old is the tree I wonder?

Wednesday, 19 April 2017

How to avoid predators in a rock pool

I was snorkelling at Murrays Beach (Booderee National Park, Jervis Bay, New South Wales) last weekend and it was fabulous with warm clear water and a blue sky. The rocky shore dips into the bay creating ribs of reefs where a multitude of sea-life live. The highlights on this trip were cuttlefish hiding under ledges and huge schools of small fish of various shapes and colours.

But I don't bother taking photographs when snorkelling, I like to just watch the life go by. It was only when up top-side and walking along the shore afterwards that I took a few shots of life in the rock pools.

At first, things looked quiet and as though there were no animals living in the pools, until I saw a little movement in the green seaweed. A Sea Hare Aplysia dactylomela was slowly munching its way through the algae. It was only when it crossed a relatively open patch that I noticed it. If it had stayed in the thicker fronds, I would not have seen it.

So, I sat quietly and sure enough other creatures began to move.

A small shrimp twitched. The sea hare depended on coloured skin as camouflage in the weed, the shrimp had evolved a mostly transparent body for hiding from predators. That method allows it hide on any colour of substrate.

Then several shells began to walk across the bottom, but not with molluscs inside them, hermit crabs. They have adapted to use shells for protection.

And lastly, I noticed a school of small fish. As they were swimming up near the surface they should have been the first things to detect. Their bodies too, were quiet transparent and it was their shadows on the pool bottom that attracted my predator's eye. But, their schooling and safety in numbers appears to be their main defence tactic, which is fine as long as there are others in the school slower than oneself. There are twelve in the photograph, how many were there the next day, or the day after. There were White-faced Herons about.