Lesson

Oysters in Australia

Australian fact. The Aussie English fact for today. We’re going to talk all about oysters and I’m going to be a little ‘shellfish’ and talk all by myself for five minutes, okay, about what I want to talk about. I’m being ‘shellfish’. Get it? Alright.

So, facts about oysters and the oyster farming industry in Australia.

So, oysters are a type of mollusk, as we said at the start there, guys, and it is a fancy way of saying a snail, right? A snail. Except these mollusks are from a group known as ‘bivalves’, which means ‘two shells’. So, any time you find things like… I don’t know. What are they? Clams and scallops, I guess. It’s hard for me to think of different kinds of mollusks. Those are all bivalves where you’ve got two sides to their shell.

So, oysters can range in size from a few centimetres to a foot across, so 30 centimetres across, and they can live for many decades, sometimes up to 40 years, right? That’s older than me. Mind-blowing.

Oysters live in marine and brackish water habitats, so the ocean, estuariesrock pools, that sort of stuff, salty water, but not in freshwater streams, rivers, and lakes, etc.

There are three species commonly eaten in Australia. So, oysters are a common food here in Australia. The Sydney Rock Oyster, the Pacific Oyster, and the Flat Oyster. The Pacific Oyster is commonly eaten worldwide, however, the Sydney Rock Oyster is an endemic Australian species, it’s only found here in Australia, and has an annual production of 70 million oysters. That’s like three oysters for every person in Australia, and that rakes in about $35 million every year. Pretty pennies. That’s a lot of money.

So, oyster farming is one of, if not the, oldest and most valuable aquaculture industries in Australia, and it has been contributing to the economy for over 140 years.

Besides being part of the food industry, though, oysters are also a big part of the jewellery industry, or more specifically, the pearling industry. The pearling industry has also been around for over 100 years since the late 1800s when pearlers is first established themselves in Broome, which is on the north western coast of Western Australia in the Kimberley region.

So, by the year 1910, Broome was the largest pearling centre in the world benefiting from newly introduced diving suits as well as its fertile waters and the booming international pearl button market of the time.

The pearls extracted from Western Australian oysters are some of the largest and most lustrous found in the world, and in recent years a single Australian pearl fetched a price of $1.5 million dollars when it was sold. That’s ridiculous. That’s like a house or two. Jesus!

Aside from the pearls, the shells of oysters known as ‘Mother of Pearl’ as well as their meat is also highly valued and traded around the world.

It’s nice to hear how humans can exploit oysters and make money by feeding them to people or beautifying the rich with their shells and pearls, but what about the environment? What do oysters do for the environment?

So, oyster shells provide important habitat and substrate for other marinedwelling organisms as their shells are uneven and when they grow they tend to grow together on rocks, and they provide numerous nooks and crannies for other animals such as worms and snails, sea squirtssponges, small crabs, and fishes, all to hide amongst these shells and they can more easily evade predators thanks to these friendly oyster neighbours.

Oysters are also filter feeders, that is that they feed by filtering the water of things including microscopic planktonsuspended particles in the water, and even bacteria. And they can filter four to five litres per hour, which on a daily basis is the equivalent of 50 x 2-litre Coke bottles. Wow! That’s a lot. 100 litres a day! As a result, they keep water’s incredibly pristine clean, and other organisms like seagrasses and seaweeds and coral can, thus, more easily absorb light and grow healthily, you know, to keep these sorts of environments really, really healthy.

The last cool fact about oysters is that they can change their gender, they can change their sex. All oysters start out as males and they spawn, that is, they release sperm into the water in their early life. However, at around two to three years of age, they’ve grown to a big enough size and they have developed sufficient energy stores that they can now produce eggs and release eggs when they spawn, you know, as females, because, obviously, it requires a lot more energy to create one egg than it does to create one sperm.

So, let me know, guys, have you ever eaten an oyster? And are you the proud owner of some real pearls?

Fun fact about me, I do not own any pearls, unfortunately, and I have never eaten an oyster. I’ve seen them many times, but to be honest they kind of freaked me out, and I am yet to ever eat one.


Vocabulary:

ST – Something

SO – Someone

SW – Somewhere

A benefit – an advantage or profit gained from something.
A button – a small disc or knob sewn on to a garment, either to fasten it by being pushed through a slit made for the purpose or for decoration.
A clam – a marine bivalve mollusk with shells of equal size.
A decade – 10 years
A filter feeder – an animal (such as a clam or baleen whale) that obtains its food by filtering organic matter or minute organisms from a current of water that passes through some part of its system.
A foot – ~30cm – The foot is a unit of length in the imperial and US customary systems of measurement.
A gender – the state of being male or female (typically used with reference to social and cultural differences rather than biological ones).
A habitat – the natural home or environment of an animal, plant, or other organism.
A mollusk – an invertebrate of a large phylum which includes snails, slugs, mussels, and octopuses. They have a soft unsegmented body and live in aquatic or damp habitats, and most kinds have an external calcareous shell.
A predator – an animal that naturally preys on others.
A rock pool – a pool of water among rocks, typically along a shoreline.
A scallop – an edible bivalve mollusk with a ribbed fan-shaped shell. Scallops swim by rapidly opening and closing the shell valves.
A sea squirt – a marine tunicate which has a bag-like body with orifices through which water flows into and out of a central pharynx.
A sex – either of the two main categories (male and female) into which humans and most other living things are divided on the basis of their reproductive functions.
A shell – the hard protective outer case of a mollusk or crustacean.
A snail – a mollusk with a single spiral shell into which the whole body can be withdrawn.
A sperm – the male reproductive cell in animals and plants; a spermatozoon.
A sponge – a primitive sedentary aquatic invertebrate with a soft porous body that is typically supported by a framework of fibres or calcareous or glassy spicules. Sponges draw in a current of water to extract nutrients and oxygen.
A stream – a small river
A substrate – the surface or material on or from which an organism lives, grows, or obtains its nourishment.
A worm – any of a number of creeping or burrowing invertebrate animals with long, slender soft bodies and no limbs.
Absorb ST – take in or soak up (energy or a liquid or other substance) by chemical or physical action.
An egg – the female reproductive cell in animals and plants; an ovum.
An estuary – the tidal mouth of a large river, where the tide meets the stream.
Annual – on a yearly basis; occurring once every year
Aquaculture industry – the industry that involves the farming of organisms that live in water, e.g. fish, crabs, seaweed, etc.
Around the world – all over the planet
Beautify ST – make ST beautiful
Boom – experience a period of great prosperity or rapid economic growth.
Brackish – (of water) slightly salty, as in river estuaries.
Contribute to ST – give (something, especially money) in order to help achieve or provide something.
Endemic – (of a plant or animal) native or restricted to a certain place.
Energy stores – the quantities or supplies of energy kept by an animal for use as needed
Evade ST – escape or avoid (someone or something), especially by guile or trickery.
Exploit ST – make full use of and derive benefit from (a resource).
Fancy – elaborate in structure or decoration.
Fertile waters – waters that produce or capable of produce abundant vegetation or crops.
Fetch a price of… – receive or demand a price of…
Filter ST – pass ST through a device to remove unwanted material.
For over 140 years – for more than 140 years
Freak SO out – have a wildly irrational reaction to ST
Lustrous – having lustre; shining
Marine-dwelling – living in marine environments
Mind-blowing – incredible; impressive; shocking
Nooks and crannies – small out of the way places
Plankton – the small and microscopic organisms drifting or floating in the sea or fresh water, consisting chiefly of diatoms, protozoans, small crustaceans, and the eggs and larval stages of larger animals. Many animals are adapted to feed on plankton, especially by filtering the water.
Pretty pennies – from ‘to cost a pretty penny’, meaning to be expensive
Pristine – clean and fresh as if new; spotless.
Produce ST – create ST
Rake it in – make a lot of money.
Range in size – vary in size
Require ST – need for a particular purpose.
Ridiculous – deserving or inviting derision or mockery; absurd.
Seagrasses – a grass that grows in marine environments
Seaweeds – large algae growing in the sea or on rocks below the high-water mark.
Spawn – (of a fish, frog, mollusk, crustacean, etc.) release or deposit eggs.
Sufficient – enough; adequate.
Suspended particles – small particles that are floating in a gas or liquid
The equivalent of… – the equal of…; the same as…
Uneven – not level or smooth