The Story The Story of a of a

SwordfishSwordfish

Andrew Andrew SammutSammut

““It is intended that this It is intended that this presentation…. gives an presentation…. gives an overview of the life of…. overview of the life of…. AA SWORDFISHSWORDFISH….. from ….. from

when it is born till it when it is born till it reaches adulthood reaches adulthood

and….later on finds itself and….later on finds itself on….on….

…………. Andrew’s . Andrew’s plate for lunch”plate for lunch”

Dad meets mum- SpawningDad meets mum- Spawning

Best spawning grounds are found Best spawning grounds are found in the Mediterranean Seain the Mediterranean Sea

Adults spawn in all months except Adults spawn in all months except January and FebruaryJanuary and February

Spawning is most intensive from Spawning is most intensive from end of June to Augustend of June to August

Mum swordfish lays 2 to 5 million Mum swordfish lays 2 to 5 million eggseggs

The Swordfish is BornThe Swordfish is Born……

Eggs are fertilized Eggs are fertilized externally and float at externally and float at the sea surface due to the sea surface due to

the presence of a droplet the presence of a droplet of oil of oil

They hatch after 2.5 days They hatch after 2.5 days

Babies (fry) up to 5 kg Babies (fry) up to 5 kg have been recorded from have been recorded from

October to DecemberOctober to December

Large numbers of babies Large numbers of babies are found from are found from

November to MarchNovember to March

Characteristics of Swordfish FryCharacteristics of Swordfish Fry

Swordfish fry - recently hatched fish Swordfish fry - recently hatched fish larvae - are different from adultslarvae - are different from adults

Upper & lower jaws are equally Upper & lower jaws are equally prolongedprolonged

Bodies are long, thin and snakelike Bodies are long, thin and snakelike They are covered with rough, spiny They are covered with rough, spiny

scales and plates scales and plates Tails are rounded Tails are rounded Have just one long dorsal and anal finHave just one long dorsal and anal fin

Growth RateGrowth Rate Swordfish grow extremely fast during their first Swordfish grow extremely fast during their first

year of life and may reach 90cm by one year of age year of life and may reach 90cm by one year of age

After two years of age, females tend to grow faster After two years of age, females tend to grow faster and to a larger size than malesand to a larger size than males

Females are heavier than males at the same lengthFemales 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 Reaches reproductive maturity at about 5 to 6 years of age, when about 2m in lengthyears of age, when about 2m in length

The Adult SwordfishThe Adult SwordfishMaximum life span of 9 years Maximum life span of 9 years

Characteristics of an Adult Swordfish Characteristics of an Adult Swordfish (Xiphias gladius)(Xiphias gladius)

Known asKnown as Piscispat or Pixxi spad in Piscispat or Pixxi spad in MalteseMaltese

Lose all teeth and scales by adulthoodLose all teeth and scales by adulthood

The Sharp BillThe Sharp Bill

The swordfish is The swordfish is named after its named after its sharp bill which sharp bill which resembles a swordresembles a sword

Sharp bill is used to Sharp bill is used to injure prey injure prey

Defensive against Defensive against natural predatorsnatural predators

Cold bloodedCold blooded

Have special Have special organs near eyes organs near eyes and brain which and brain which improves heatingimproves heating

This helps in their This helps in their vision and catch vision and catch their prey easilytheir prey easily

Not Schooling FishNot Schooling Fish

Swim alone or……Swim alone or……

…….. in loose aggregation having a .. in loose aggregation having a swordfish 10 meters apart from the swordfish 10 meters apart from the otherother

Very powerful and vigorous when harpooned Very powerful and vigorous when harpooned or hookedor hooked

Known to have run their bill like a sword Known to have run their bill like a sword through planking of small boatsthrough planking of small boats

Known for their powerful Known for their powerful jumping on surface called jumping on surface called

breachingbreaching

Enjoys swimming at surface of Enjoys swimming at surface of water airing their dorsal finwater airing their dorsal fin

TheThe Favorite Food for the Favorite Food for the SwordfishSwordfish

Pelagic fish such as flying fish, Pelagic fish such as flying fish, barracuda and small tunabarracuda and small tuna

Fish in Benthic zoneFish in Benthic zone

The squidThe squid

Pelagic fish on which the Pelagic fish on which the swordfish feedsswordfish feeds

The Pelagic ZoneThe Pelagic Zone

Open ocean zoneOpen ocean zone Part of water located Part of water located

in open waterin open water Part of water not Part of water not

near coastnear coast Different zones Different zones

characterized by characterized by their depththeir depth

Swordfish feeds on fish found in Swordfish feeds on fish found in the Benthic Zonethe Benthic Zone

Ecological region at Ecological region at lowest part of the lowest part of the waterwater

Enjoys eating SquidEnjoys eating Squid

Enemies of the SwordfishEnemies of the Swordfish

Very few natural predators in adulthood Very few natural predators in adulthood but highly vulnerable when youngbut highly vulnerable when young

Short fin mako shark is one of few sea Short fin mako shark is one of few sea creatures which are big and fast enough creatures which are big and fast enough to kill a swordfishto kill a swordfish

Other enemies are sperm and killer whaleOther enemies are sperm and killer whale

Short fin mako sharkShort fin mako shark

Sperm WhaleSperm Whale

Killer WhaleKiller Whale

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

FisheriesFisheries

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

By CatchBy Catch

Long linersLong liners Consists of a Consists of a

main line, main line, usually usually several miles several miles long, which long, which is supported is supported in the water in the water column by column by floats and floats and from which from which baited hooks baited hooks are are suspendedsuspended

In addition, swordfish are often In addition, swordfish are often an incidental catch in the tuna an incidental catch in the tuna

fishery known as by catchfishery known as by catch

This is used on allThis is used on all

non-target fish whether non-target fish whether retained and sold or retained and sold or discarded (Hall, 1996) discarded (Hall, 1996)

Fishing netsFishing nets

TheThe Swordfish is caught !!!Swordfish is caught !!!

Swordfish ready to be cut….Swordfish ready to be cut….

The swordfish is cleanedThe swordfish is cleaned

Swordfish is being slicedSwordfish is being sliced

The swordfish is cut into The swordfish is cut into piecespieces

Swordfish & Mercury IntakeSwordfish & Mercury Intake

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

Practical tips to avoid Practical tips to avoid mercury consumptionmercury consumption

Avoid eating excessive amounts of any single type Avoid eating excessive amounts of any single type of fishof fish

Avoid eating the internal organs of the fish—they Avoid eating the internal organs of the fish—they

typically contain higher contaminant concentrations typically contain higher contaminant concentrations than the fleshthan the flesh

High-risk individuals — pregnant women, women of High-risk individuals — pregnant women, women of

childbearing age, and children under age 15 — childbearing age, and children under age 15 — should limit their consumption of swordfishshould limit their consumption of swordfish

Use cooking methods like baking or broiling to Use cooking methods like baking or broiling to allow fats and juices to drain awayallow fats and juices to drain away

The Swordfish in Andrew’s plateThe Swordfish in Andrew’s plate

Andrew’s Visit to San LucjanAndrew’s Visit to San Lucjan

Fort San Lucjan - Malta Centre Fort San Lucjan - Malta Centre for fisheriesfor fisheries

Andrew and Mark (scientific Andrew and Mark (scientific officer at San Lucjan)officer at San Lucjan)

A swordfish in a frameA swordfish in a frame!!

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

The Flying Fish - the favorite The Flying Fish - the favorite food of the Swordfishfood of the Swordfish

Stuffed Fish including a SwordfishStuffed Fish including a Swordfish

Preparing the long linePreparing the long line

A turtle caught by By CatchA turtle caught by By Catch

Additional InformationAdditional Information

Ernest Hemmingway (1899-1961), one of Ernest Hemmingway (1899-1961), one of America’s best writers and winner of Nobel America’s best writers and winner of Nobel Prize for Literature (1954) spent long years Prize for Literature (1954) spent long years in Cuba. in Cuba.

One of his pleasures of life was fishing for One of his pleasures of life was fishing for swordfish.swordfish.

This is reflected in his novel, This is reflected in his novel, The Old Man The Old Man and the Seaand the Sea, which was published in 1952., which was published in 1952.

Later the novel was adopted for a famous Later the novel was adopted for a famous film, in which actor Spencer Tracey stared.film, in which actor Spencer Tracey stared.

The Swordfish CatchThe Swordfish Catch

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

World Record SwordfishWorld Record Swordfish

382 kg382 kg Caught in 1936Caught in 1936 In ChileIn Chile

Swordfish Painting colored by AndrewSwordfish Painting colored by Andrew

AcknowledgementsAcknowledgements

Mr Mark Gatt - Scientific Officer – San LucjanMr Mark Gatt - Scientific Officer – San Lucjan

My parents and sister, KristinaMy parents and sister, Kristina