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Marine Discovery Centre
Climate Change Fishing Change
Understanding Climate Change in Victoria's Fisheries
Climate Change Hot Spot Map
The world’s climate is changing at an unprecedented rate
Climate change may affect:
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Currents
Environmental flows
Extreme weather conditions
Nutrient supply
Ocean chemistry
Ocean temperatures
Rainfall
Winds
The impacts of these changes on world fisheries may present significant risks and new
opportunities, particularly in “hot spot” areas across the globe.
The south-eastern coast of Australia, including Victoria’s coastline, is a “hot spot”
A hot spot is an area experiencing rapid change, i.e. sea surface temperature.
Victoria’s Fisheries
Victoria’s Fisheries are diverse and geographically extensive
(Warm currents moving south warm water species entering Victoria)
We have productive coastal, bay, inlet and freshwater fisheries where commercial, aquaculture
and recreational fisheries occur.
Key fisheries include species of abalone, aquarium finfish, Australian salmon, barramundi, black
bream, blue mussel, calamari, eel, flathead, King George whiting, Murray cod, rock lobster,
snapper, trout, and yabby.
Some of the habitats which support these fisheries include bays & estuaries, beaches & dunes,
kelp forests, mangroves & salt marshes, open water, rocky reefs and seagrass & mudflats.
Fisheries Victoria has examined the linkages between priority species and changing
environmental variables. Two examples are provided here with King George whiting & black
bream. Investigate some of the key processes that are likely to influence the resilience of these
stocks to climate change.
Whilst these changes present a challenge, research suggests climate change will also see
improved offshore fishing opportunities for recreational fishers in Victoria with a wide range of
species on offer.
Image: Bays &estuaries
Image: Beaches & dunes
Image: Kelp forests
Image: Mangroves & salt marshes
Image: Open water
Image: Rocky reefs
Image: Seagrass & mudflats
King George whiting
King George whiting: Importance
King George whiting is an important recreational & commercial fishery in Victoria.
King George whiting: Importance – Estimated commercial value
King George whiting: Importance – Catch data
King George whiting: Importance – Nutritional value
Seafood is well known for its nutritional value being: low in kilojoules, high in readily digestible
protein, low in saturated fat, high in good fats (such as omega 3’s and omega 6’s), low in
cholesterol, high in vitamins A B E & D and high in minerals iodine and calcium. In fact seafood
is the best natural source of Omega 3 oils which provide many health benefits particularly in the
fight against coronary disease, high blood pressure, arthritis, asthma and depression.
Grilled whiting with limoncello and oregano
by Pete Evans from his book Fish published by Murdoch Books
This is a very simple dish but with beautiful subtle flavours. It is particularly lovely with a side
dish of roasted fennel.
Ingredients (serves 4)
 250 ml (1 cup) extra
 Virgin olive oil
 Grated zest and juice of 2 lemons,
 Plus 2 lemons to serve
 1 bunch oregano
 90 ml limoncello or other lemon liqueur
 4 whole King George whiting
Method
Preheat oven to 180°C.
 Stir together the olive oil, lemon zest and juice in a saucepan and place over medium
heat until nearly boiling.
 Pour into a large flat bowl, immediately add the oregano and limoncello and leave for 30
minutes.
 Add the whiting to the marinade and leave for 10 minutes.
 Heat your barbecue grill and cook the whiting until cooked through, basting with the
marinade several times.
 Pour a little more marinade over the fish and serve with lemon quarters.
King George whiting - Life Cycle
Eggs and larvae are pelagic/floating and are transported by currents, feed on zooplankton
Larvae settle in seagrass beds in sheltered bays and inlets
Juveniles and adults move to deep seagrass patches and adjacent sand areas, feed on
benthic/bottom dwelling crustaceans
Adults reach maturity at 3 - 5 years and move to coastal spawning grounds associated with
rocky reefs
King George whiting Environment – Seagrass bed habitats
Seagrass provides a habitat for King George whiting, providing shelter and a place to forage for
food such as invertebrates.
Environment – Medium temperature and storminess
Seagrass habitat for King George whiting
Environment – High temperature and storminess
Reduced seagrass habitat for juvenile King George whiting
Environment – Very High temperature and storminess
Significant losses of seagrass habitat for juvenile King George whiting
Projections
CSIRO predicts that seagrass abundance and extent may decline in the future due to:
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sea-level rise
increased storminess
Warmer temperatures
This may reduce the ability of King George whiting to complete their life cycle.
Adaptation
Fisheries Victoria is examining key seagrass regions in Port Phillip Bay to determine how
important they are for juvenile King George whiting. From this work we aim to provide natural
resource managers with advice on conserving important seagrass habitats to enhance King
George whiting stock resilience to climate change.
Black bream
Black bream: Importance
Black bream is an important recreational & commercial fishery in Victoria.
Black bream: Importance – Estimated commercial value
Black bream: Importance – Catch data
Black bream: Importance – Nutritional value
Seafood is well known for its nutritional value being: low in kilojoules, high in readily digestible
protein, low in saturated fat, high in good fats (such as omega 3’s and omega 6’s), low in
cholesterol, high in vitamins A B E & D and high in minerals iodine and calcium. In fact seafood
is the best natural source of Omega 3 oils which provide many health benefits particularly in the
fight against coronary disease, high blood pressure, arthritis, asthma and depression.
Seafood parcels
by Alex Giannuzzi (MDC Education Officer) from an old family recipe book
This is a quick & tasty dish my Mum used to make when I was younger. My boys love it with a
side serve of vegies.
Ingredients (serves 4)
 1 carrot, peeled
 1 Celery stick
 1 green shallot
 4 (about 480g) thin black bream fillets
 12 scallops
 Ground black pepper
 20g (1 tbs) butter
 150mls thin cream
 1 lemon, juiced
 2 tsp wholegrain mustard
Method
Preheat oven to 180°C.
 Cut carrot, celery and green shallot into very thin 5cm-long sticks. Divide vegetable
sticks into 4 equal portions.
 Place black bream fillets on a board and place a vegetable portion on the end of each.
Top with 3 scallops. Gently roll up fillets and place seam-side down on a baking tray
lined with non-stick baking paper. Sprinkle with pepper.
 Bake in pre- heated oven for 15-20 minutes or until fish just flakes when tested with a
fork.
 Meanwhile, melt butter in a saucepan. Add cream, lemon juice and mustard and stir until
simmering. Simmer for 1 minute.
 To serve, place the fish parcels onto plates and spoon over the cream sauce.
Black bream - Life Cycle
Adults spawn in 15 - 28 Cwaters from spring to early summer
Eggs float in the water column and hatch after 2 days
Larvae remain in water column for ~ 1 month
Juveniles and adults found throughout estuaries, feed on benthic/bottom dwelling
invertebrates
Adults reach maturity at 1 - 4 years and move upstream in sheltered estuaries to spawn
Environment – Environmental flows & salt wedge formation
Environment – Moderate rainfall
Freshwater inflows create a salt wedge in the estuary, which is what black bream need to spawn
successfully. (Freshwater is less dense than salty water)
Moderate flows lead to salt wedge formation in the estuary
Environment – Very low rainfall
Extended periods of drought
Environment – Very high rainfall
High fresh water flows flush estuary and saltwedge is lost
Projections
CSIRO predicts that Victoria may receive less rainfall in the future and heavy rainfall events may
be more intense. Water flow in the estuary resulting from these events may reduce the ability of
black bream to complete their life cycle.
Adaptation
Fisheries Victoria is examining key black bream estuarine fisheries to determine suitable flow
regimes. From this work we aim to provide catchment managers with advice on environmental
flow requirements to enhance black bream resilience to climate change.
New Opportunities
Mahi Mahi (Coryphaena hippurus) & Cobia (Rachycentron canadum)
Changing offshore currents on the east coast of Victoria may result in new offshore species
entering our fisheries. The major current in this region (the East Australian Current) has
strengthened by 20 per cent over the last 50 years and is likely to continue to strengthen by
another 20 per cent by 2100. This is likely to result in more warm water sub-tropical species
being encountered by Victorian anglers. In recent time Victorian anglers have reported catches
of Cobia and Mahi Mahi in Victoria’s coastal waters. These are two highly valued recreational
species normally encountered in the warmer waters of Queensland and New South Wales.
Acknowledgment
New Opportunities
Illustrations: Paul Lennon for Fisheries Victoria
Projections: © CSIRO (2007) based on mid-range emission scenario (A1B)
http://climatechangeinaustralia.com.au/technical_report.php
Life cycles: © South-Eastern Australia Program: Adaptation of fish and aquaculture sectors and
fisheries management to climate change in South-Eastern Australia (2010)
‘Hot spot’ map: adapted from Hobday, A. J. and G. T. Pecl (in review). Identification of global
marine hotspots: sentinels for change and vanguards for adaptation. Proceedings of the
National Academy of Sciences.