Invertebrate of the Month - limpet

Sceale Bay (SA) -
Grant Hobson

Andrew Bolt of the Herald Sun kindly brought to our attention a number of facts about coral bleaching and how it was all a left wing green conspiracy. He forgot to mention that the Queensland Productivity Commission had said that it the reef was under serious threat, especially the inshore reefs and particularly from sedimentation and nutrient enrichment from increased run-off..

Clay pots found in the Black Sea from the Forth Century BC have been full of fish - catfish to be specific.

The are two types - True and False. They are both molluscs like occy's, but they are gastropods ('ol stomach foot). The true molluscs have a gill at the front, and the false limpets have a lung. Follow the link for more info.

Different fish seem to have different levels of ability to either receive pain and to process it into an awareness. The cartilaginous fish such as sharks don't have the receptors (called nociceptors) that would allow pain information to be transferred to the brain. Sharks have been found with multiple ray stings and apparently oblivious to it. Other fish, such as trout clearly have the necessary anatomy.

The next question was do the fish have the brain capacity to process the signal and understand it as pain. It turns out that a little part in the cerebellum processes the signal that we understand as pain is missing from fish. It means that fish do actually receive a signal but not process it into a signal that we perceive as pain. But this does not mean that fish should be treated with less care. There can still be impacts on fish from stressful situations.

Sceale Bay of 1500 km WNW of Melbourne. It is about an hour from Ceduna, in SA. The land is harsh and dry and the ocean conditions are straight from a surfing magazine. Some have said that the town is a location where lunacy is its own reward.

The story started with a proposal for a large aquactuture operation in an area where the locals considered it quite inappropriate. The problems were not just aesthetics, but escapes, huge biomass in a small area, dispersal of nutrients released by that biomass, and the legacy of the pilchard kills of the mid 1990's.

While all this was going on, the locals were aware of an Australian sea lion colony that the rest of the world had not discovered. It was an amazing collection of sea lions, and it turns out that it is the 5th largest breeding colony in the world.

So what was proposed was to put a large fish delicatessen within 3 km of a large sealion colony. Evidence shows that the sealions would camp outside and attack, with some obvious impacts.

The story has a happy ending. The aquaculture proposal was moved away for Sceale Bay and a an AFL footballer got involved in the naming of the Island.

"Gravity"

"Pedro don't go"

"Shelter"

Mark Pengilly

Those Bloody Mckennas