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The Story of a Swordfish Andrew Sammut. It is intended that this presentation…. gives an overview of the life of…. A SWORDFISH….. from when it is born.

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Presentation on theme: "The Story of a Swordfish Andrew Sammut. It is intended that this presentation…. gives an overview of the life of…. A SWORDFISH….. from when it is born."— Presentation transcript:

1 The Story of a Swordfish Andrew Sammut

2 It is intended that this presentation…. gives an overview of the life of…. A SWORDFISH….. from when it is born till it reaches adulthood and….later on finds itself on…. ……. Andrews plate for lunch

3 Dad meets mum- Spawning Best spawning grounds are found in the Mediterranean Sea Adults spawn in all months except January and February Adults spawn in all months except January and February Spawning is most intensive from end of June to August Mum swordfish lays 2 to 5 million eggs

4 The Swordfish is Born … Eggs are fertilized externally and float at the sea surface due to the presence of a droplet of oil They hatch after 2.5 days Babies (fry) up to 5 kg have been recorded from October to December Large numbers of babies are found from November to March

5 Characteristics of Swordfish Fry Swordfish fry - recently hatched fish larvae - are different from adults Swordfish fry - recently hatched fish larvae - are different from adults Upper & lower jaws are equally prolonged Upper & lower jaws are equally prolonged Bodies are long, thin and snakelike Bodies are long, thin and snakelike They are covered with rough, spiny scales and plates They are covered with rough, spiny scales and plates Tails are rounded Tails are rounded Have just one long dorsal and anal fin Have just one long dorsal and anal fin

6 Growth Rate Swordfish grow extremely fast during their first year of life and may reach 90cm by one year of age Swordfish grow extremely fast during their first year of life and may reach 90cm by one year of age After two years of age, females tend to grow faster and to a larger size than males After two years of age, females tend to grow faster and to a larger size than males Females are heavier than males at the same length Females are heavier than males at the same length Maximum size: 4.5m in length and 540 kg in weight Maximum size: 4.5m in length and 540 kg in weight Reaches reproductive maturity at about 5 to 6 years of age, when about 2m in length Reaches reproductive maturity at about 5 to 6 years of age, when about 2m in length

7 The Adult Swordfish Maximum life span of 9 years

8 Characteristics of an Adult Swordfish (Xiphias gladius) Known as Piscispat or Pixxi spad in Maltese Known as Piscispat or Pixxi spad in Maltese Lose all teeth and scales by adulthood Lose all teeth and scales by adulthood

9 The Sharp Bill The swordfish is named after its sharp bill which resembles a sword The swordfish is named after its sharp bill which resembles a sword Sharp bill is used to injure prey Sharp bill is used to injure prey Defensive against natural predators Defensive against natural predators

10 Cold blooded Cold blooded Have special organs near eyes and brain which improves heating Have special organs near eyes and brain which improves heating This helps in their vision and catch their prey easily This helps in their vision and catch their prey easily

11 Not Schooling Fish Swim alone or…… ….. in loose aggregation having a swordfish 10 meters apart from the other

12 Very powerful and vigorous when harpooned or hooked Very powerful and vigorous when harpooned or hooked Known to have run their bill like a sword through planking of small boats Known to have run their bill like a sword through planking of small boats

13 Known for their powerful jumping on surface called breaching

14 Enjoys swimming at surface of water airing their dorsal fin

15 The Favorite Food for the Swordfish Pelagic fish such as flying fish, barracuda and small tuna Pelagic fish such as flying fish, barracuda and small tuna Fish in Benthic zone Fish in Benthic zone The squid The squid

16 Pelagic fish on which the swordfish feeds

17 The Pelagic Zone Open ocean zone Open ocean zone Part of water located in open water Part of water located in open water Part of water not near coast Part of water not near coast Different zones characterized by their depth Different zones characterized by their depth

18 Swordfish feeds on fish found in the Benthic Zone Ecological region at lowest part of the water Ecological region at lowest part of the water

19 Enjoys eating Squid

20 Enemies of the Swordfish Very few natural predators in adulthood but highly vulnerable when young Very few natural predators in adulthood but highly vulnerable when young Short fin mako shark is one of few sea creatures which are big and fast enough to kill a swordfish Short fin mako shark is one of few sea creatures which are big and fast enough to kill a swordfish Other enemies are sperm and killer whale Other enemies are sperm and killer whale

21 Short fin mako shark

22 Sperm Whale

23 Killer Whale

24 But the greatest threat to swordfish is HUMANS!!!!!

25 Fisheries Caught in gill nets with harpoon & on longlines (see slide further on re: local visit to Fort San Lucjan) Caught in gill nets with harpoon & on longlines (see slide further on re: local visit to Fort San Lucjan) By Catch By Catch

26 Long liners Consists of a main line, usually several miles long, which is supported in the water column by floats and from which baited hooks are suspended

27 In addition, swordfish are often an incidental catch in the tuna fishery known as by catch This is used on all This is used on all non-target fish whether retained and sold or discarded (Hall, 1996) non-target fish whether retained and sold or discarded (Hall, 1996)

28 Fishing nets

29

30 The Swordfish is caught !!!

31 Swordfish ready to be cut….

32 The swordfish is cleaned

33 Swordfish is being sliced

34 The swordfish is cut into pieces

35 Swordfish & Mercury Intake While swordfish sold on commercial markets is closely monitored to make sure that methyl mercury levels remain below the 1.0 ppm action level, most experts urge those concerned about chemical contaminants to take certain precautions While swordfish sold on commercial markets is closely monitored to make sure that methyl mercury levels remain below the 1.0 ppm action level, most experts urge those concerned about chemical contaminants to take certain precautions

36 Practical tips to avoid mercury consumption Avoid eating excessive amounts of any single type of fish Avoid eating excessive amounts of any single type of fish Avoid eating the internal organs of the fishthey typically contain higher contaminant concentrations than the flesh Avoid eating the internal organs of the fishthey typically contain higher contaminant concentrations than the flesh High-risk individuals pregnant women, women of childbearing age, and children under age 15 should limit their consumption of swordfish High-risk individuals pregnant women, women of childbearing age, and children under age 15 should limit their consumption of swordfish Use cooking methods like baking or broiling to allow fats and juices to drain away Use cooking methods like baking or broiling to allow fats and juices to drain away

37 The Swordfish in Andrews plate

38

39 Andrews Visit to San Lucjan

40 Fort San Lucjan - Malta Centre for fisheries

41 Andrew and Mark (scientific officer at San Lucjan)

42 A swordfish in a frame !

43 A comparison in size between Tuna Fish (above) and Swordfish (below)

44 The Flying Fish - the favorite food of the Swordfish

45 Stuffed Fish including a Swordfish

46 Preparing the long line

47 A turtle caught by By Catch

48 Additional Information Ernest Hemmingway ( ), one of Americas best writers and winner of Nobel Prize for Literature (1954) spent long years in Cuba. Ernest Hemmingway ( ), one of Americas best writers and winner of Nobel Prize for Literature (1954) spent long years in Cuba. One of his pleasures of life was fishing for swordfish. One of his pleasures of life was fishing for swordfish. This is reflected in his novel, The Old Man and the Sea, which was published in This is reflected in his novel, The Old Man and the Sea, which was published in Later the novel was adopted for a famous film, in which actor Spencer Tracey stared. Later the novel was adopted for a famous film, in which actor Spencer Tracey stared.

49 The Swordfish Catch Ernest Hemming in Cuba with his friend Mike Lerner and their swordfish catch (from Hemmingway in Cuba by H. Hemmingway and C. Brennan, Ruggedland, 2005) Ernest Hemming in Cuba with his friend Mike Lerner and their swordfish catch (from Hemmingway in Cuba by H. Hemmingway and C. Brennan, Ruggedland, 2005)

50 World Record Swordfish 382 kg 382 kg Caught in 1936 Caught in 1936 In Chile In Chile

51 Swordfish Painting colored by Andrew

52 Acknowledgements Mr Mark Gatt - Scientific Officer – San Lucjan My parents and sister, Kristina


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