Lauren is back from her trip – this page and the entries in the right hand column will give you a good idea of how much she enjoyed and benefited from the experience.

Dr Lauren E. Smith is a marine biologist who specialises in shark research; she is a keen surfer, freediver and SCUBA diver and loves nothing more than to combine these activities with her Lauren freediving in egyptpassion for sharks.

Lauren, who has made a significant contribution to the SSTP has taken a 3 month sabbatical from her current research position based in the N.E. of Scotland in the UK and will shortly be heading off to the Philippines to undertake as many shark based activities as possible.

The ‘Google Map’ found here may help give you some idea of the location of the various posts.

Lauren says:

Sharks have evolved for over 400 million years, surviving some of the earth’s greatest mass extinctions. They are superbly adapted to their environment: apex predators, intelligent with unique immune systems and yet for all this perfection they are vulnerable particularly to the actions of man.

Therefore I believe that the key way to save these animals is through education; through informed understanding, misrepresentation and fears can be replaced with appreciation, respect and compassion.

It is for these reasons that I have taken a 3 month sabbatical from my current research position , and am heading off to the Philippines for as many shark based activities as possible!

The primary reason for me choosing the Philippines is because it is home to a well established shark research laboratory, with an excellent reputation the – Thresher Shark Research and Conservation Project (TSRCP), based on Malapascua Island, off the North East tip of Cebu, where I will be working for 2 months. The TSRCP’s mission statement is as follows:

To promote and disseminate shark research, education and conservation to a broad local, regional and international public and scientific outreach”.

A statement that I fully endorse and follow when conducting my own shark research.

Please visit the TSRCP page for further information.

Pelagic Thresher Shark

thresher shark

Image courtesy of: http://www.threshersharkproject.org/TSRCP/Home.html

Malapascua Island

island

Image courtesy of: http://www.mynetbizz.com/pages/philippines/malapascua-island-cebu.jpg

During my stay in the Philippines I will also be going to visit the whale sharks that descend on the waters of Donsol, located at the Southern tip of Luzon Island for December to May each year. Here I will be getting in the water with the whale sharks and meeting with employees of Donsol EcoTour to find out more about the whale sharks, with a view to developing future research possibilities.

In the first week of June I will be flying to the Republic of Palau, 500 miles east of the Philippines for a 2-week stay. Palau is made up of over 300 volcanic and coral islands, it attracted a lot of media attention in September of last year when it effectively created the worlds first ‘shark sanctuary’ after banning all commercial shark fishing in it’s waters. Here I will be SCUBA diving and freediving and hopefully in doing so observing yet more shark’s in their natural environment.

Palau

palau

Image courtesy of: https://a082d246f9custmedia.vresp.com/library/1246310284/011424b952/palau.jpg

The Thresher Shark Research and Concervation Project (TSRCP)

From their site.

Declaration

We are the only accredited group to have conducted, and who continue to conduct scientific research on thresher sharks in the Malapascua area.  We are also the only   group to be currently working on thresher sharks in the Philippines.    We are a community based not-for-profit research organisation and we are not political.  Our opinions, if we have any, are derived exclusively from the integrity of our work, all of which is peer reviewed.

Aims

  • To investigate the behaviour of Pelagic thresher sharks in response to resident cleaner fishes on Monad Shoal, the Philippines.
  • To investigate correlations between parasite presence and injury on Pelagic thresher shark individuals to their respective cleaning interactions.
  • To improve established methods of observing the behaviour of sharks in situ.
  • To assess the population dynamics of Pelagic thresher shark visit frequency.
  • To inform conservation initiatives to manage fisheries and dive tourism in relation to their relative impacts on the abundance of Pelagic thresher sharks in the area.

Hypothesis

Individual Pelagic thresher sharks make regular visits inshore to a shallow seamount for cleaning by Cleaner and Moon wrasses where they are incidentally affected by dive tourism and vulnerable to over-exploitation by fisheries.

Objectives

  • Identify and map the presence of ectoparasites on Pelagic thresher sharks.
  • Design photographic ethograms for thresher shark and cleaner wrasse interactions to investigate behavioural patterns.
  • Examine spatial and temporal (seasonal) distributions of cleaning stations, cleaner fishes and Pelagic thresher sharks in relation to each other.
  • Identify individual sharks to assess population structure and visit frequency.
  • Develop a model for managing Monad Shoal as a protected area for Pelagic thresher sharks.

Pelagic Thresher Shark

Background and Rationale

The Pelagic thresher shark (Alopias pelagicus) is an oceanic species whose biology and behavioural ecology are largely unknown due to study limitations.  Fisheries and by-catch data indicate that it is found in warm and temperate offshore waters, that it matures late, has low fecundity and is vulnerable to over-exploitation.  International conventions have recognized some shark species to be ‘threatened’, promoting nations to implement protection policy, but species listed comprise those which have received comprehensive scientific investigation, and whose biology and behavioural ecology are well understood.  Knowledge that Pelagic thresher sharks regularly visit a seamount in the Philippines presents an unique opportunity to study this rarely observed oceanic shark.  Preliminary investigations at this site during 2005 identified significant relationships between shark presence and cleaning activity conducted by resident Cleaner and Moon wrasses (Labriodes dimidiatus and Thalassoma lunare).  Cleaning activity relating to sharks has never been investigated in the wild before, but the observable interactions seen at this site explain why these mainly oceanic sharks venture into shallow coastal waters, where they are vulnerable to fishing and disturbance from dive tourism.  Understanding their behavioural ecology will provide important information to aid initiatives to protect them.

Monad Shoal is located within the Visayan Sea, 8.16 km due east from the southern beach on Malapascua Island, Cebu, the Philippines.  The seamount is an open water site rising 250 meters from the sea floor to 15 – 25 meter depths.  Early morning presence of Pelagic thresher sharks on the shoal drives the local dive and tourism industries, fuelling 80% of the regional economy.

Publications

Oliver S. P., Hussey N. E., Turner J. R., Beckett A. J., Oceanic Sharks Clean at Coastal Seamount.  Plos ONE 2009;  Publication pending revision.

Oliver S. P., 2006.  The Behaviour of Pelagic Thresher Sharks (Alopias pelagicus) in Relation to Cleaner Fishes (Labroides dimidiatus & Thalassoma lunare) on Monad Shoal, Malapascua Island, Cebu, The Philippines.  University of Wales MSc thesis, 2006.

Conservation

Classification

All 3 thresher shark species are now listed as VULNERABLE by the International Union for the Conservation of Nature and Natural Resources (IUCN press release 2007).

Vulnerability

Thresher sharks are among the more demanded shark species for global fisheries.  They are prized for their high quality meat which is used fresh, frozen, smoked and dried-salted.  Their fins are prized for shark-fin soup, their livers for vitamin extraction and their hides are used in the production of leather goods.  Alopias pelagicus represents 12% of Taiwan’s shark catch with an average 3,100 units (222 MT) taken per annum.  Methods employed in the hunt for thresher  shark species are dominated by commercial and recreational long-line fishing practices.  Their low fecundity  of 2 pups per litter over long gestation periods classifies them as a K-species (Liu et al. 1999).  This factor combined with their relative proclivity for habitat subjected to high intensity oceanic fisheries, raises concern over the viability of population sustainability.  In 2002, Baum et al. reported that 80% of global thresher shark populations have been lost to fishing pressure over the past 15 years.  The results of this study showed that if unified conservation efforts are not applied, thresher sharks are likely to be eradicated from many of their chosen habitats.

The Philippine Issue

Commonly fetching 150 kg of meat and 1000 kg dried fins (£1.75 and £11.75 respectively), Thresher sharks are found in fish markets across The Philippines.  Thresher sharks are known to be directly targeted for the Asian shark fin trade in Batangas Bay, Sogon, and Bohol, and are suspected to be hunted in many other regions.  In March 2008, the ‘Thresher Shark Research and Conservation Group’ assessed the extent to which thresher sharks are fished out of Philippine waters as beyond the sustainability of their population thresholds.

Management

Because thresher sharks follow transboundary migration routes (Hewitt 2001) and are phylogeographically isolated (Tonatuh 2004),  there is a real need for  regional, national and international co-operation when considering the implementation of conservation management initiatives.   While real inroads toward protecting these animals have been made at the regional level within the Philippines, to date no agreement exists to protect them beyond boundaries.

Solutions

Since revenues have been calculated  in excess of 6,000,000 (£70,250) per annum for one daily observation of a live thresher shark by an average 3 SCUBA divers visiting Malapascua Island, the ‘Thresher Shark Research and Conservation Group’ has endeavoured to promote similar ecotourism elsewhere in the Philippines.  To date, the comparative cost benefit analysis of live thresher sharks being observed by SCUBA divers versus their value dead in a fish market (8,125/£95 mean), has drawn favourable responses from conservation agencies and policy makers alike.  This is an ongoing effort and is expected to consume much of our focus in the coming years.

To find out more about the first move to legislate protection for threshers sharks in the Philippines by the TSRCP and their efforts to raise public awareness please visit:-

http://www.threshersharkproject.org/TSRCP/Conservation.html

Conclusions so far

Diver Impact

We quantified significant habitat loss to the dived area of Monad Shoal (80 – 90%) and assessed that the pulverising effects of diver trampling is responsible for most of the rubble which characterises the site (figures 1 – 4).  Additional damage has been caused by boats anchoring in spite of the clear presence of 5 marked buoys (figures 1 – 2).  Overall not less than 2 of the 5 cleaning stations we established as ‘critical thresher shark habitat’ in 2005 have been completely eradicated by diver interference.  To date, no evidence  has been found to support claims that the area is currently, or has been recently, dynamite blasted.  The natural behaviour of visiting elasmobranchs on Monad Shoal (thresher sharks, grey reefs, manta & devil rays) is perturbed by aberrant  diver interaction (figure 4 ).  Shark perturbance can be mitigated by using established site management and ‘respectful’ diver behaviour protocols.

Anatomical Cleaning Distribution

We found significance in the number of times thresher sharks are cleaned in their pelvic zones.

Behaviour

We described ‘Circle & Clean’ as a novel behavioural unit to elasmobranch ethology.

Ethograms

We advanced the analysis of shark behaviour through the development of photographic ethograms and mapped thresher shark swim paths and interactions with cleaner fish to quantify behavioural trends.

Predictability

We developed a system to predict where and when thresher sharks are most likely to frequent.

Cleaning Stations

We characterised cleaning stations, cleaner fishes and thresher sharks in relation to each other.

All text & images reproduced from the TSRCP website: http://www.threshersharkproject.org/TSRCP/Home.html

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