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Black Tip Shark (Carcharhinus tilstoni) Photographs and Information


Other Known names for this shark is Blacktip whaler, blacktip reef shark,  tropical shark.

A medium-sized, long-snouted whaler shark with a bronzy to greyish dorsal coloration, the first dorsal-fin origin more or less over the pectoral-fin insertions, no interdorsal ridge, black tips, and slender, erect, serrated upper teeth.



The Australian Blacktip Shark is currently known only form the continental shelf of tropical Australia. Genetic studies and tagging indicate a single stock off northern Australia. It occurs from close inshore to a depth of about 150 m. It can be found throughout the water column, but mostly in midwater or near the surface. Sometimes C. tilstoni sharks form large aggregations

Body fusiform: interdorsal ridge absent. Snout moderately long, internarial space 1.1-1.6 in preoral length; labial furrows small and inconspicuous. Upper teeth erect to slightly oblique, slender and finely serrated (somewhat coarse basally). Lower teeth erect, more slender, finely serrated or smoothed-edge. First dorsal-fin origin usually over or just behind pectoral-fin insertions, exceptionally just in front of pectoral-fin free tips. Tooth count 32-35/29-31. Total vertebrae 174-182; precaudal 84-91

Dorsal surface bronze, fading to grey after death and in preservative. Ventral surface pale. A pale stripe extends along each flank from the pelvic fin to below the first dorsal fin. All fins (except sometimes the pelvic and anal fins) black-tipped.

Black-tip sharks are born at 60 cm and attains 200 cm. Males and females mature at about 110 cm and about 115 cm respectively.

Currently known only from the continental shelf of tropical Australia. Occurs from close inshore to a depth of about 150 m. Found throughout the water column but mainly in midwater or near the surface.

 

Did you know? A group of sharks is called a "shiver"

Did you know? A shark is the only fish that can blink with both eyes

Scientific Name -Carcharhinus tilstoni
Location -
Season Year round
Size -360cm 350Kg 150-200cm 25-50Kg
Australian Species Code -37 018901
Taste, Texture -

 

Nutritional Information
For every 100 grams raw product
for Shark fillet.

Kilojoules 420 (100 calories)
Protein 21.2 g
Cholesterol 48 mg
Sodium 90 g
Total fat (oil) 0.9 g
Saturated fat 27% of total fat
Monounsaturated fat 20% of total fat
Polyunsaturated fat 53% of total fat
Omega-3, EPA 17 mg
Omega-3, DHA 252 mg
Omega-6, AA 30 mg

 

Scientific:  Carcharhinus tilstoni
German:  Australischer Schwarzspitzenhai
English:  Australian blacktip shark
French:  Requin borde de Australia
Spanish:  Tiburón macuira de Australia

This species is very similar to, and has only recently been separated from, the common blacktip shark. These two species can currently be reliably distinguished only on enzyme systems and vertebral counts. The Australian Blacktip shark often occurs in large aggregations. It has a seasonal reproductive cycle producing, 1-6 pups in January after a 10 month period. Ageing studies show that it grows relatively quickly (about 20 cm in the first year) and attains sexual maturity in 3-4 years. The diet consist of teleost fishes, and to a lesser extent, cephalopods. Tagging and genetic have shown that there is only one stock off northern Australia. About 60% of the tag recoveries were made within 50 km of the tagging site and the farthest recaptured site was 1113 km away.

 


Angling for Blacktip Shark:

It is a prized sporting fish.


First you will need these essentials:
- A sturdy fishing rod and reel
- A size "7" hook
- A 2 foot wire leader attached to the hook
- At least 30 lb test fishing line
- Super sharp fishing knife - sharks skin it very tough
- Some bug repellent cause mosquitoes love the smell of bait

Your bait can be frozen or fresh, these blacktip sharks love mullet and small pan-fish. Slice a half inch chunk of bait and set it on the hook, get in on there good! Then throw it out yonder and set the drag, this is very important, you need to set the drag open yet snug enough to not get any backlash when bolts for it. With any luck the crabs and catfish will stay away from your bait. When a shark sees your bait it will pick it up in a hurry and run away from it school as you will find out when your reel starts singing, then it will stop and chow down on the bait, this is when you need to set the hook by giving your rod a decent yank. Then the shark will likely start fighting and you may even see him jump out of the water!

Once you got him on deck or the beach be very careful, those teeth are sharp and he is pissed. Be humane and go for an instant kill by penetrating the heart with a sharp knife slicing all the way down and then start gutting the shark immediately to keep the meat fresh. If you are going to stay a while make sure to pack him on ice or let him chill in the water on a bait hook until your ready to go. Remember try not to touch your pole until you hear that drag sing, cause a lot of marine life will be out there trying to nibble your bait and if a shark sees that he will scare it away and grab it.

These blacktip sharks can be fished in the summer to early fall then they disappear. They travel in schools so if you find one, more will likely be around. Look out for dolphins or porpoise's as they scare away the sharks, if they are around go fish someplace else.


SHARK ATTACKS

International Shark Attack Files - How stats are gathered, the history of the file, how to report a shark attack and who to contact about the ISAF. Lots of information. Maps, graphs and reports based on statistics from the International Shark Attack File. Your risk of shark attack compared to your chances of getting bit by animals in NY City, hit by lightning, having an accident in your home, or being attacked by an alligator. Learn what the different types of attacks are, when and where they are most likely to occur.
http://www.flmnh.ufl.edu/fish/Sharks/ISAF/ISAF.htm


Cooking Shark:

Shark fillets are commonly sold as boneless fillets or flake in Australia. Other names such as rock salmon are used overseas. New Zealand gummy shark (Mustelus lenticulatus) is often sold as rig or lemon fish.

The blacktip shark is very good eating as they have a chicken-like taste but also have a robust yet delicate meaty flavor like a scallop. Best way to enjoy them is to grill them on a barbecue, I have a great recipe so look for that later.

Colour of Raw Fillet:

Pink

Texture/firmness:

medium/firm, some species flaky.

Fat Content:

Low

Smaller sharks have sweet and delicious flesh, and are popular for their boneless and thick flakes. They have been commonly used for the traditional fish and chips but should not be overlooked for barbecuing, poaching, braising and baking. Marinate first in oil and lemon to tenderise the flesh.

Remove the skin before cooking, particularly when barbecuing, to prevent it shrinking and tearing the flesh.

Excellent for soups, shark is most popularly used in Asian-style shark fin soup and can also be successfully combined with crab meat. The texture of shark also makes it a great ingredient for fish cakes or kebabs.

Make good use of the firm flesh and enhance the flavour by cooking slowly with strong tomato and herb sauce.

Ammonia odour in shark flesh can be reduced by soaking it in milk, vinegar and water or lemon juice. However, if ammonia odours are detected, it is advisable to reject the product.

Barbequed Shark Steaks w. Herbs - Shark steaks, garlic, lemon juice, fresh oregano, fresh parsley, fresh dill, ground black pepper.

Marinated Shark Steaks - Shark steaks, soy sauce, vinegar, lemon juice, oil, parsley, garlic, black pepper, green onions.

Peppered Shark - Shark steaks, shallots, brandy, stock, cream, freshly ground pepper.

Mako Shark with Pineapple Salsa - Mako shark fillets with a pineapple, lime, red onion, mint, cilantro salsa

Shark Salad - Carrots, broccoli, mushrooms, green peppers and Italian salad dressing over lettuce.

Microwave Cooking Times for Fish
- Fish fillets – 5 minutes per 500g on medium-high, +50 seconds more for thicker fillets, or until flesh flakes
- Whole fish - Large – 6 minutes/750g on medium
- Whole fish – Small – 3-4 minutes on medium

Easy Fish Recipes - From How To Cook Fish

       
Tomato Seafood Sauce
for Blackened Shark
Mako Shark 2 Ways Shark - Cooking Dogfish Shark Curry
       

Commercial Fishing for Blacktip Shark:

The Australian blacktip shark is one of the two (together with C. sorrah) most abundant shark species in commercial gill-net catches off northern Australia

Some shark species are heavily exploited (sometimes wastefully, for their fins only), and the fisheries are strictly managed.

The Blacktip Shark was the principal shark species taken by a Taiwanese gillnet fishery that operated from 1974-1986 off northern Australia. The species was caught for its meat, and to a lesser extent, its fins. Until 1991, it was taken by Taiwanese longliners in northern Australia and utilised in the same way. This blacktip also forms the basis of a small Australian gillnet fishery (up to 500 tonnes annually), which markets the flesh mainly in south-eastern Australia. The flesh has a relatively high mercury concentration.

With the declaration of the Australian Fishing Zone in 1979, foreign vessels were excluded from the Gulf of Carpentaria and from 40 nautical miles (74 km) to 50 nautical miles (93 km) off the Wessel Islands and Arnhem Land coast. Further restrictions were introduced in 1986 in response to declining shark catch rates. The reduction of net lengths to 2,500 m rendered the Taiwanese fleet uneconomical, and despite permitted use of baited longlines, foreign fishing operations in northern Australian waters ceased by the end of 1986. A small domestic fishery also developed over this time and is still in operation to this day. C. tilstoni is primarily targeted for its flesh, which is sold under the marketing name “flake”, and the fins. The flesh has a relatively high mercury concentration.

Processors of Black Tip Shark  |  Exporters of Black Tip Shark  |  Importers of Black Tip Shark  |
Wholesale Suppliers of Black Tip Shark  |  Agents for Black Tip Shark

Processors of Shark  |  Exporters of Shark  |  Importers of Shark  |
Wholesale Suppliers of Shark  |  Seafood Agents for Shark

See Also: Shark, Baby  |  Shark, Black Tip  |  Shark, Blue  |  Shark Fins  |  Shark, Ghost   |  Shark, Gummy  |  Shark Liver Oil  |  Shark, Mako  |  Shark, Moro  |  Shark, Porbeagle  |  Shark, Reef  |  Shark, Rig  |  Shark, School
 


Following from Department of Agriculture, Fisheries & Forestry - Australian Government
http://www.daff.gov.au

Northern Shark Fishery
The main fishing methods are gillnetting and longlining, and most activity and catch occurs in waters off the Northern Territory. Historically, the main commercial species have been blacktip sharks—Australian blacktip (Carcharhinus tilstoni), common blacktip (C. limbatus) and spot-tail shark (C. sorrah)—and grey mackerel (Scomberomorus semifasciatus). The Australian and common blacktip are difficult to differentiate in the field and so have been treated as a species complex, with the assumption that the majority are the Australian blacktip. Other tropical shark species, including hammerheads and tiger shark (Galeocerdo cuvier), are also caught. Over time, the species targeted have varied in the different jurisdictions with changes in gear and targeting practices. Sharks are also taken as bycatch and byproduct in other fisheries in the region.

Northern Territory Offshore Net and Line Fishery
Most of the fishing in the waters off the Northern Territory occurs inshore (<12 nm from the coast), targeting blacktip sharks and grey mackerel. The status of the fishery is reviewed in Buckworth & Beatty (2008). Pelagic gillnets (limited to 2000 m net length) are the main fishing gear, but longlines can be used. From the 1980s to early 1990s, fishing effort was variable but generally declining. From 1994 to 1997, effort increased but then declined again until 1999. Effort then increased to the historical peak in 2003 (1800 vessel days). In 2005, measures were introduced to contain effort, which declined to 899 vessel days in 2006 and 729 vessel days in 2007. There are currently 17 licences in the fishery, with 11 active in 2007.

The catch has been variable, generally mirroring effort changes. The highest catch was reported in 2003, at 1687 t, comprising 899 t of shark (of which 501 t was blacktip shark) and 766 t of grey mackerel. Total landings have decreased since 2003, to a total catch of 1193 t in 2007; this included 925 t of shark (of which 493 t was blacktip sharks) and 240 t of grey mackerel. The total catch was valued at $3.39 million, and the catch of ‘other sharks’ ($1.51 million) was more valuable than the catch of blacktip ($0.76 million). The total catch per unit effort (CPUE) has been variable and was declining in the late 1990s, raising concerns that the stocks had not recovered from the heavy exploitation by the foreign fleet. However, the CPUE has been increasing in recent years. Grey mackerel catches have increased steadily throughout the past two decades, and currently have the highest landings and value of any single species in the fishery.

The fishery is currently an approved WTO under the EPBC Act until 28 November 2010.

Queensland Gulf of Carpentaria Inshore Fin Fish Fishery
The Queensland Joint Authority manages sharks in the Gulf of Carpentaria waters off Queensland as part of the Gulf of Carpentaria Inshore Fin Fish Fishery. The status of the fishery is reviewed in Roelofs (2009). The fishery has two sectors: an offshore sector (7–25 nm) targeting tropical sharks and grey mackerel, and an inshore sector (0–7 nm) targeting barramundi and also catching sharks. The main gear used is gillnets, with the offshore sector limited to a maximum of 1200 m net length. In 2007, there were five licences (four active) in the offshore sector and 87 (80 active) in the inshore sector.

The total shark catch from both sectors increased rapidly between 1993 (172 t) and 1995, when it peaked at 450 t. Catch then declined until 1997. Since 1997, catch has been variable but increasing until 2003 (474 t). In 2007, the total shark catch from this fishery dropped to 147 t, of which 45 t was reported as blacktip sharks. Effort directed at sharks has declined by 70% since 2004.

The annual gross value of production (GVP) for the entire fishery has averaged $11 million since 2003. Barramundi and grey mackerel make the greatest contribution to GVP, and the contribution from sharks has declined since 2003 (Roelofs 2009).

Queensland considers the target species in this fishery to be ‘fully exploited’ (Roelofs 2009). Some concern has been expressed about the sustainability of the shark species and grey mackerel at the current catch levels, due to a paucity of species-specific information (Roelofs 2009). The fishery is currently an approved WTO under the EPBC Act until 20 August 2010.

Western Australia Joint Authority Northern Shark Fishery
For reporting and assessment purposes, the Western Australia Joint Authority Northern Shark Fishery (WAJANSF) is combined with the adjacent Western Australia North Coast Shark Fishery (WANCSF), which is managed by the Western Australian Government. Western Australia assesses the status of these fisheries in McAuley (2008b). The WAJANSF operates from longitude 123°45’E to the border with the Northern Territory, and the WANCSF operates from longitude 114°06’E to 123°45’E. Since 2005, demersal gillnets and longlines have been permitted within both fisheries, with longlines being the main gear used. There are nine licences in the WANCSF and five in the WAJANSF; however, only two licences were active in both fisheries in 2007.

There was a rapid increase in effort in these fisheries between 1999–2000 (<100 000 hook days, standardised to include gillnet effort) and 2004–05 (1.2 million hook days). The total catch had a corresponding increase from around 100 t (1999–2000) to 1294 t (2004–05). Fishing practices also changed, with a shift from primarily gillnetting in the north-eastern region of the fishery to increased demersal longline effort in the south-western region (McAuley & Baudains 2007b). The changes reflected an increased targeting of sandbar sharks (Carcharhinus plumbeus) and other large species, including tiger shark, hammerhead shark, pigeye shark (C. amboinensis) and lemon shark (Negaprion acutidens). The changed practices also resulted in a reduction in the catch of blacktip sharks.

Sandbar sharks were recognised as the target species for the fishery in 1997–98, and catch in the northern fisheries peaked at 762 t in 2004–05. This species was also taken in significant amounts in southern shark fisheries in Western Australia. The stock assessment for sandbar sharks, which considers all take of the species across Western Australian fisheries, suggested that cumulative levels of fishing mortality were increasingly unsustainable between 2000–01 and 2003–04 (McAuley et al. 2007). A 58% decline in breeding stock abundance has also been inferred from fisheryindependent survey data from the north-coast region (McAuley & Baudains 2007b).

As mentioned above, Western Australia has recently introduced new management measures to address risks to the sustainability of a number of shark species. New management arrangements that were put in place in 2005 in the WANCSF to prevent targeting of sandbar sharks included closure of about 60% of the fishery to protect breeding stock and limits on the permitted number of fishing days (200 gillnet and 100 longline fishing days). At the same time, new management arrangements were agreed with industry for the WAJANSF, including a limit of 400 gillnet days and 200 longline days. These new measures resulted in an 89% drop in total effort between 2004–05 and 2005–06, down to 141 923 hook days (152 days out of the permitted 900 days). There was a corresponding 85% decrease in total reported catch, from 1294 t (2004–05) to 189 t (2005–06). Longlines accounted for 84% of the 2005–06 catch. The fisheries are now intended to target blacktips; the 2005–06 catch was dominated by blacktip sharks (76 t), pigeye sharks (43 t), hammerhead sharks (27 t) and tiger sharks (12 t), with negligible catch of sandbar sharks (<1 t). The estimated value was $490 000 for 2005–06.

Confidentiality requirements associated with the small number of operators in the fisheries prevent the publication of 2006–07 catch and effort figures. McAuley (2008b) reports that the total fishing effort in 2006–07 was significantly lower than pre-2005–06 levels and that the 2006–07 catches of all species were significantly lower than pre-2005–06 levels. It is expected that the catches will remain at these low levels or be further reduced in the future.

In 2008, the WAJANSF’s WTO approval under the EPBC Act was revoked because a formal management plan had not been finalised. The WANCSF’s approval expired in early 2009 and has not been renewed. Therefore, product from these fisheries cannot be exported.

Other catches, including illegal fishing
Sharks are caught as bycatch and byproduct in other state and territory fisheries and the Northern Prawn Fishery (NPF). In Western Australia, the 2006–07 catch by other statemanaged fisheries was less than in previous years (31 t in 2005–06), due to a ban on retention in non-shark fisheries (McAuley & Baudains 2007b; McAuley 2008b). The Northern Territory estimates that other fisheries landed 39 t in 2007, with retention banned in some fisheries or limited by byproduct limits in others (Buckworth & Beatty 2008). The retention of any shark product has been banned in the NPF since 2001.

Australia allows access by traditional Indonesian fishers to a limited area of the AFZ off north-western Western Australia. The size and composition of shark catches taken by these traditional fishers are unknown.

Illegal fishing activity by Indonesian vessels increased in northern Australian waters until 2004–05. Sharks were a primary target for these vessels, particularly for fins, based on the catch found on apprehended vessels. The Australian Government responded with a major increase in the level of surveillance and policing, as well as collaborative programs in Indonesia, which resulted in a substantial decrease in the level of illegal fishing. Coastwatch reported an 80% reduction in sightings from 2006 to 2007. In 2007–08, 156 Indonesian vessels were apprehended in northern Australian waters (compared with 216 in 2006–07 and 367 in 2005–06). There were also nine legislative forfeitures, in which vessels had catch and gear confiscated (compared with five in 2006–07 and 178 in 2004–05). The volume and species composition of the catches are not well understood, and the reduction in apprehensions has limited research that was focused on quantifying catches. The impact of illegal fishing on the shark stocks is currently unknown.

Status of the stocks
All joint authorities are limited-entry fisheries, and each has regulations controlling the gear permitted. In Western Australia and the Northern Territory, the number of fishing days is also constrained. The Northern Australian Fisheries Committee (NAFC)—which includes representatives from the Australian, Queensland, Northern Territory and Western Australian Governments—aims to facilitate complementary management and research across the jurisdictions for shared stocks. Support from the NAFC and recent Fisheries Research and Development Corporation projects have improved species identification of the catches and increased observer coverage in these fisheries.

The NAFC established a crossjurisdictional assessment group to examine the status of shared shark stocks. This group has met twice. At the second meeting, in May 2008, it updated the blacktip shark stock assessment, initially developed in the 1990s. The earlier assessment estimated that the sustainable yield for blacktip sharks should be at least 2000 t per year from the Northern Territory, Queensland and Western Australia fisheries combined. The 2008 assessment indicated that the fishery catch levels are below the estimated sustainable yield and that the current level of effort is sustainable. The estimates are uncertain due to a range of factors, including the accuracy of the data from the Taiwanese fishery, the unknown illegal fishing catch and species identification issues. However, the CPUE trend from the Northern Territory, where the majority of blacktip shark is caught, has been increasing in recent years, and current catch levels are substantially less than those taken by the foreign fleet historically.

Recent genetic studies (Ovenden et al. 2009) show little genetic differentiation across the north between the spot-tail and Australian blacktip shark, suggesting that it may be appropriate to manage these as single stocks across the region. However, the results for common blacktip shark suggest that there may be genetic subdivision within Australian waters. Therefore, if the Australian and common blacktip are managed as a complex, it may be appropriate to recognise separate stocks between Western Australian and Northern Territory/Queensland waters.

Genetic studies also detected an apparent change in the relative proportion of the common and Australian blacktip sharks in the catch. In the 1980s, the Australian blacktip was the major component of the catch, with the common blacktip caught in much lower numbers (Australian: common, 300:1) (Stevens & Davenport 1991). Recent studies have indicated a ratio closer to 1:1 (Ovenden et al. 2009). Biological information also suggests that the common blacktip is less productive than the Australian blacktip. It is unclear whether the change is real or due to sampling methods. Further genetic research is currently in progress to investigate the current species composition, but this issue is a key uncertainty in the assessment.

Whereas the Australian blacktip is restricted to Australia, the spot-tail and common blacktip also occur in Indonesian waters. Studies for the spot-tail shark suggest that the Australian populations are separate from populations in waters off central Indonesia. However, other shark species—the blue shark (Prionace glauca) and scalloped hammerhead (Sphyrna lewini)—showed no evidence of subdivision between Australia and Indonesia and so may require cooperative management. The high level of shark fishing in Indonesian waters and the lack of a full understanding of the connectivity between populations in Australian and eastern Indonesian waters suggest that the northern shark populations should be monitored closely.

In 2004, the Australian Government released its National Plan of Action for the Conservation and Management of Sharks. Recent research and improvements in data collection and monitoring from northern shark fisheries align with priorities identified by the national plan. Implementation of the national plan will be reviewed in 2009. The crossjurisdictional assessment group developed a collaborative research plan in 2008 to support a more robust assessment of these shark species. The research plan recommends the development of direct estimates of fishing mortality to monitor stock status. This recommendation was supported by the NAFC, and research is currently under way in the Northern Territory to develop this approach. It would address the limitations of the use of CPUE, which is influenced by factors other than stock abundance, such as changes in targeting practices over time. The plan also includes the development of a harvest strategy framework.

 


 

 


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