Download Part 2 The Fish - Sapphire Coast

MEETING OF THE WATERS
A journey on the marine side of Australia’s Coastal Wilderness
Part 2 –
The Fish
The Fish (and Sea Squirts)
Over 100 species of fish intermingle in the waters of the region, with a rich and varied mix of
temperate and tropical species. Morwong, Luderick, Drummer, Bream, Flounder, Kingfish,
Tailor and Ling are but a few. The coast also provides safe haven for the Eastern Blue
Groper, the marine emblem of New South Wales.
Eastern Blue Groper
Drummer
Yellowtail Kingfish
Morwong
Luderick
Black Bream
Flounder
Tailor
Rock Ling
Large pelagic fish species that migrate into our waters include the charismatic Sailfish and
Marlin, Tuna and Salmon. Flying Fish can also be spotted in deeper water, and signal the
arrival of warmer currents.
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Sailfish
Bluefin Tuna
Marlin
Eastern Australian Salmon
Yellow winged flying fish
A star visitor is the Southern Blue Fin Tuna, weighing up to 200 kilograms. These iconic and
endangered fish - fast disappearing from other marine zones - pass through our waters in late
June and early July during their long southward bound migration. They travel from their
breeding grounds in the Indian Ocean, near Indonesia, right down the east coast of Australia
and into south Australian waters, often in the company of cousins such as the Yellow Fin and
Big Eyed Tuna. They are mostly found some 50 km offshore, exciting both commercial and
recreational fishers.
A fish of particular curiosity is the Snapper. It’s widespread throughout southern Australia, but it
appears that we have a unique pygmy sub-species in our waters. Regular adult snapper grow
to 17 kilograms, but this local pygmy stops at 7 kilos, and is short and stumpy. And although a
schooling species, each fish has its own individual appearance.
Snapper
Emperor Angelfish
White Ear Damselfish
The region is also the most southern point for wayward tropical fish species such as the Damsel
Fish and Angelfish, who journey here from the faraway Great Barrier Reef.
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Sharks
Shark populations have been decimated throughout the global oceans, with most species
endangered or on the brink of extinction. Although shark encounters are rare in our waters a
number of species have been reported, most commonly the Bull Shark. Smaller species such
as the Draftboard Sharks are commonly seen.
White Tip Reef Shark
Bull Shark
Draftboard Shark
Swell Shark
There have been confirmed sightings of the critically endangered and heavily protected Grey
Nurse Shark as well as the king of all sharks, the Great White. The risk to swimmers and
divers is minimal, as sharks generally prefer deep, offshore waters. Sightings are rare, and
attacks in this region are unknown.
Great White Shark
Grey Nurse Shark
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Sharks are an ancient form of fish, with cartilage instead of bones. The region is host to fossils
of these distant ancestors, dating back to the late Devonian period about 355 million years ago.
Fossils occur in rocks in the Eden area and north of Tathra in Mimosa Rocks National Park.
This is described in the accompanying series A journey through the earth history of Australia’s
Coastal Wilderness in Part 8 Ancient volcanoes and Armoured fish.
Sharks are part of the class of vertebrates called the Chondrichthyes (from the Greek meaning
cartilage fish). Sharks are in a subclass that includes rays and skates. There is a wide variety of
rays in the region such as the large Black Stingray, Bull and Eagle rays.
Black Stingray
Bull Ray
Eagle Ray
Many protected species, officially designated by the NSW Government, find sanctuary in our
waters, including the Great White, and Wobbegong sharks. Eastern Blue Devilfish, Weedy
Sea Dragon and Black Rock Cod.
Eastern Blue Devilfish
Weedy Sea Dragon
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Black Rock Cod
Whale sharks
A leviathan of the deep that visits our coast is the Whale Shark. This gentle plankton-eater is a
relative of the shark (the subclass Elasmobranchii – the sharks, rays and skates) and is in the
carpet shark group (with their distinctive ornate skin patterns) that includes the Wobbegong
shark.
The NSW portion of Australia’s Coastal Wilderness is at the southern boundary of its migratory
path, and they have been encountered as far south as Eden. The most recent sighting was in
February 2012, when excited locals gathered on Tathra Wharf to watch a young adult swim by.
Their random visits here seem to coincide with warmer spikes in the local sea temperature and
a related surge in plankton, the whale shark’s principal food.
Whale Shark
Ocean Sunfish
The Ocean Sunfish is also an occasional visitor. This is the largest bony fish in the world with
an adult average weight of one tonne.
Ocean sunfish
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Big Belly Seahorse
Green Moray Eel
Feeding frenzies
Feeding frenzies are inspired by the formation of baitfish balls and involve many oceanic
creatures. It’s a chain reaction set in motion by the presence of krill, which are predated upon
by large schools - or ‘balls’ – of pilchards and mackerel. The fish in turn are targeted by birds
from above and predators from below. Birds such as gannets pierce the water like arrows.
Seals, dolphins, whales, sharks and predatory fish pursue their quarry through the water
column, often breaking the surface. It’s a feeding frenzy unlike any other, and visually
spectacular - the sea a churning cauldron.
Baitfish ball and feeding shark
Sea Squirts
Cunjevoi (or ‘cunjies’ or sea squirts as they are often known) are commonly found on the rocky
shores and as debris on beaches. They were a food source for Indigenous people. Today they
are used as bait.
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Cunjevoi
These are not fish, nor are they plants. They are in fact related to us (Chordata) as animals with
a primitive backbone and are classified as a Tunicate. They are found around the edge of the
low-tide mark forming mats over the rocks. These mats are sometimes covered in green or
brown algae and have a tough brown exterior or 'tunic'.
This is a seriously weird group of animals. They are living fossils dating back to the earlyCambrian Period, some 500 million years ago - older than the oldest rocks in the south coast
region. They belong to the class Ascidiacea that is worldwide with over 2000 species. Their
closest local relative is the Sea Tulip, also locally found.
Sea Tulip
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