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Manx Basking Shark Watch Work and Results Summary 2011
by Jackie Hall MSc, BSc (hons) BA: Voluntary Coordinator MBSW.
The format of the 2011 report will be a little different to previous years. It will be more like an update of the various work and activities and there will be a brief overview of the maps and statistics for the 2011 season. If anyone would like more detailed information you may contact us via the website or look at the news section for news from 2011
Manx Basking Shark Watch 2011 Season Graphs
The map shows all the MBSW public sighting reports for 2011. It is typical of the pattern seen since the project started in 2005. The numbers are down on every other year though.
This is the Map for May 2011. The season started very well. there was plenty of plankton at this stage of the year.
This is the Map for June 2011. We had several days in the first week of June when there were large groups of sharks off Niarbyl and Fleshwick. It was all looking right for a good season when we had a couple of bad storms and then the zooplankton numbers crashed. As there was now relatively little food for the sharks numbers declined rapidly.
This is the map of MBSW basking shark sightings for July! Not typical AT ALL. It was the worst July for shark spotting that we have had since we started the sighting scheme in 2005. i do understand, though, that it was just as bad in 2001. There was virtually no zooplankton when we did plankton trawl. One could hardly blame the basking sharks for pushing off to better feeding grounds. Large groups were seen up in Scotland. I do not know whether these were 'our' Manx sharks though.
The map shows the MBSW reports for August. Just a smattering, they didn't come back.
MBSW basking shark sightings for September 2011. Just a couple, which is what we would expect, unlike July and August!
There were even a few sightings in October and November. NOT a typical MBSW year at all!
Manx Basking Shark Watch Work Update 2011
The basking shark Cetorhinus maximus is an endangered species, listed as endangered on the IUCN red list. The global population may have only about 8000 individuals remaining. They are protected in some, but not all, parts of the world but are still at risk of being by-caught in fisheries, hunted for their fins, injured or killed by boat strikes or harassed by ill-informed wildlife tourism. They breed very slowly, giving birth to about 6 young after a pregnancy that may last 3 years.
The Isle of Man is has a lot of basking shark sightings such as this one very close into Peel breakwater in 2009. This shark called "M' is number 10 on the basking shark fin photo list. As you can see people really enjoy watching the sharks. The Manx people are very proud of ‘their’ sharks and MBSW aims to help them see them safely as these people are.
The Isle of Man is a basking shark hotspot, with relatively easy access to basking sharks. Because of this, Manx Basking Shark Watch (MBSW), a Manx Wildlife Trust Project, has been studying basking sharks since 2004. The Manx Government is very aware of its responsibilities to ensure the safety of these protected animals whilst they are in Manx water and to enable responsible wildlife tourism.
The Isle of Man has many wildlife tourism boats such as "Gemini' Bob Taylor's boat. It runs out of Port St Mary. A film crew from Belgium are working on it in this photo.
Main Aims MBSW:
1: To raise public and government awareness of basking sharks, making everyone aware that they are in local waters and of public responsibilities to them.
2: Research into basking sharks.
3: Adding value to our work by cooperating with universities and NGOs studying sharks by providing them with samples and data.
MBSW is producing cutting edge scientific information on a small budget, encouraging the wider public to appreciate these fabulous animals by enabling the media to film them and report the science to a media hungry for ‘good’ wildlife news. The picture shows a film crew from Belgium. However, the amount of scientific work being done by MBSW and its team of keen volunteers has escalated beyond all expectations since it started in 2004. We desperately need to secure funding to ensure the continuity of this work for the foreseeable future.
Below is a brief overview of the various projects MBSW is involved in.
A: The Manx Basking Shark Watch (MBSW) public sighting scheme
This started in 2005, at the request of the Marine Conservation (UK). www.manxbaskingshark.com, the MBSW website incorporates a public sighting scheme, a news section and children’s and adult’s sections about basking sharks. We make all information obtained available to scientists and to the public. It gives us a clear picture of basking shark activity off the Manx coastline. We see courtship behavior and newborn sharks. Most sightings are within 1km of land and along a 40km section of the SW of the Island. All information and data is freely available to the government, the public and the media via www.manxbaskingsharkwatch.com. Accessible reports are available online, written with the public and government in mind. It is a vital tool in mainstreaming interesting in basking sharks.
B: Boat work on ‘HAPPY JACK’ the MBSW Research Boat (started 2009)
The MBSW boat Happy Jack has been in operation since 2008. Bought specifically for the shark work, it is owned by Jackie and Graham Hall and leased to MBSW. The boat is used for survey work, satellite tagging, wildlife filming, the hormone mimic study and the Basking Shark Passport Project. We could not work without it. When leasing very expensive boats during 2006-2007 they were frequently not available when the sharks were present and often proved unsuitable for the work. The boat team usually consists of 2 marine biologists, one camera person/biologist and one engineer. As well as Jackie and Graham Hall, the permanent boat crew, we use a team of up to 5 graduate and undergraduate volunteers every summer. They do shore-based effort based watches as well as rotating to the boat to gain experience.
This MBSW research boat Happy Jack. Graham Hall is stood at the front with the pole camera. He will determine the sex of the shark by looking underneath the sharks belly with this. We never get in the water for our work. This minimises disturbance to the shark.
Satellite Tagging Work:
MBSW has tagged 18 basking sharks with MK10m PAT satellite tags since 2007. We have two papers published about this tagging work Gore et al (2008) and Stephan et al (2010)/Stephan et al (2011). In Gore et al (2008) a basking shark tagged in Manx waters traveled across the Atlantic, proving that they do this (see map below). This long-distance migration of mature individuals goes some way to explaining the small genetic diversity seen in the global population.
Stephan et al (2011) and the paper presented at the European Elasmobranch conference in 2010 describe the MBSW/ APECS tagging collaboration from 2008/9. We found that most of the sharks tagged in Manx waters spent most of their time in the Irish Sea and the Northern Celtic Sea. Unfortunately their deep-water over-wintering grounds seem to overlap with areas of the Celtic Sea known for basking shark by-catch in the deepwater trawling industry. If you look at the map to the left the blue dots are our tag pop-up locations and the yellow and white dots are known basking shark by-catch.
We need to tag more basking sharks. We plan to tag with SPOT tags as well as MK10 PAT tags in future years. Graham Hall of MBSW is currently developing a method and equipment to enable us to attach these drying tags to the sharks’ fins. SPOT tags will give us fine-scale positioning of the basking sharks in real time. These tags will be much better for detailing basking shark movements in Manx waters and they stay on for up to 3 years, unlike the 230-day maximum of the MK10 PAT tags. As the location of the sharks will be known in ‘real time’ this will enable the public to closely identify with individual sharks when this information is mapped on our news site for the public. This is always a good thing when trying to improve the press image of sharks in general and basking sharks in particular. All this information is useful for the Manx and British Governments to make informed management decisions about these endangered protected animals that they are responsible for so this is not just ‘blue-sky’ research.
These three maps from Stephan et al (2011) show the horizontal tracks of 3 of the 18 basking sharks we have tagged with MK10 PAT satellite tags since 2007. All 3 of these animals were tagged in 2009. They all followed a similar track, traveling slowly southwards first and doubling back up to over-winter in an area where basking sharks are known to have been accidentally caught in fishing nets, an event that damages the fishermens’ nets and kills the shark.
This map shows the tag pop-off areas for 6 of our tags. The overall data proves that this is an important over-wintering zone for the Manx sharks. The blue dots show the sites and dates of 7 accidental by-catch of basking sharks reported by one fisherman.
‘Happy Jack’ Basking Shark Boat Survey: MBSW surveyed nearly 3000nm of sea off the Isle of Man in 2011 and 2010, recording basking sharks and cetaceans. This survey work has confirmed that the MBSW Public Sighting scheme is remarkably good at spotting and recording inshore basking sharks, we rarely find one less than 1km from shore that has not been recorded by a coastal or other boat watcher. However, the boat finds the offshore sharks (up to 6nm offshore) that the coastal watchers do not often see. This boat-based work needs to continue in order to assess the true distribution of basking sharks seen in Manx waters. The picture shows the boat training of the summer volunteers for the 2011 season.
Basking Shark Passport Project: MBSW started this initiative in 2009. Each basking shark ‘passport’ has a DNA fingerprint, a HD dorsal fin set of right and left sides of the fin, a size estimate and a gender.
We collected 11 more full basking shark IDs in 2011, making our number of basking sharks with full IDs up to 56. We have had many re-identifications within and between years. This will eventually give us a much better picture of the shark population visiting the Island. The picture shows Graham Hall with a swab of basking shark skin slime he has just obtained for DNA analysis. The technique for getting a full passport was presented at the 2011 European Elasmobranch meeting in Berlin.
Dr Leslie Noble’s department of genetics at the University of Aberdeen processes the skin slime samples. Unpublished results suggest that we have a genetically distinct population in the Irish and Celtic Sea, noticeably different at the familial level from the Irish population, which is also being tested. Our genetic work, in combination with our satellite tagging work, is starting to explain the apparent anomaly between world-wide low diversity of basking sharks and the fact that we seem to have a local ‘school’ of Irish Sea basking sharks that appear to be more closely related to each other than to the Irish population sampled on the West coast of Ireland. Most of the sharks we have tagged in Manx waters stay in the Irish and Celtic Sea. This tallies with the apparent family-level genetics we are finding in our Manx DNA samples.
The DNA runs seen here were part of Emily Hardman's honours thesis (Hardman et al 2011). It shows that swab samples 20 and 22 are from the same shark.
This may seen counter-intuitive as we know from genetics papers from Noble et al (2006) and Hoelzel et al (1992) that there is, low genetic diversity amongst basking sharks worldwide. This is explained by occasional long-distance migration of large individual sharks. The first basking shark to be show to do this was an 8m long female shark we called “Tracy’. We tagged her in Manx waters in 2007 and she crossed the Atlantic (Gore et al 2008). These findings from MBSW and its associates have huge implications for local and worldwide management issues. The British government needs to ensure that the local basking sharks are protected but the global population is so linked that it is vital that all basking sharks are protected adequately, especially as there may be only about 8000 individual basking sharks left globally.
Basking Shark Dorsal Fin Catalogue:
This was started in 2007. The first dorsal fin image is of a shark nick-named ‘M’.
It has a badly injured dorsal that has healed well. It was seen in 2005 and 2009. It is the individual in the first picture in this presentation. MBSW currently has over 100 animals registered, some with only one side of the dorsal fin, most with right and left sides. This works both with and independently of the basking shark ‘passport’ project. Not all fins are so easy to re-identify. The one below is much harder than 'M's.
All fin photographs are shared with other research groups via the Shark Trust UK. The Shark Trust are presently collating this data, some of which goes back to the 1980s. Some very interesting matches are being discovered. This fin ID project will enable amuch fuller assessment of the British basking shark population’s size and movement patterns. This work is essential otherwise we have no idea how many sharks we have and whether they are surviving long-term. It also gives each basking shark an individual identity in the minds of the public, an invaluable thing when you are trying to get people passionate about sharks. The local media can get quite excited about re-sightings of known sharks.
A double blind scientific study produced by MBSW and the Genetics Department at Aberdeen University (Hardman et al 2011) proved that our HD dorsal fin photos work very well to identify individual basking sharks. This work was collaboration between Manx Basking Shark Watch and the team of Dr Leslie Noble at the department of genetics at Aberdeen University. It showed that the genetic fingerprints from basking shark skin swabs confirmed the identity of individual sharks that had already been established from the fin photos taken by the Happy Jack team and analyzed by Eleanor Stone. These results will be presented at the European Elasmobranch Association conference in Berlin in November 2011. The dorsal fin at right is much less damaged than ‘M’s but still very easy to identify again.
Basking Sharks as Samplers of Marine Pollution by Hormone Mimics. In 2011 MBSW started working with Dr Ed Routledge's research group from Brunel University. His team is interested in pollutants known as hormone mimics. These substances, also known as endocrine disrupting chemicals (EDCs), are produced during the breakdown of plastics. They are everywhere in our environment and may also affect humans so this research has broad implications for food-chain pollution, not just for the sharks. MBSW is collecting plankton samples and basking shark skin slime to test whether these pollutants are affecting basking sharks. We also deployed 10 environmental modules known as POCIS. These will sample EDCs present in seawater. We have no results yet but this study may prove to be an informative and way to assess and long-term monitor this insidious kind of marine and global pollution.
The 7m long dead basking shark in the picture was washed up just north of Niarbyl this year. Samples obtained from it can be used for DNA testing and for this EDCs work.
Courtship and Breeding Study:
We see newborn basking sharks, many young sharks and putative courtship behaviour in Manx waters. MBSW is studying this with minimal disturbance, by using photography, film and a remote-controlled boat (our Shark-cam) with underwater camera array. This was designed by Graham Hall, technical and boat officer for MBSW.
The photograph of the 1.5m long newborn shark (left) was taken by kayaker Shane Stigant off Peel.
The trio of courting sharks seen above were photographed by Dermott Shimmin.
We are fairly confident that mating and birth occur here but we need to prove it to enable government to take steps to safeguard them during these activities. The sharks become even less responsive to boat traffic than usual when courting and are therefore at extreme risk of boat strikes.
The picture shows a large basking shark that has a serious but healed fin injury. The 1m long Shark-cam is behind it. Sharks seem undisturbed by its presence as it transmits underwater video back to the main research boat Happy Jack.
Basking Shark Education of the General Public:
As well as having its own news on the website www.manxbaskingsharkwatch.com, MBSW works very closely with the media to ensure that the wider public are aware of the presence of basking sharks in British seas and globally. We would like these iconic gentle giants of the sea to be marine ambassadors for the British Seas and for all sharks. To this end MBSW enables film crews to make wildlife movies. Many films have been made about our sharks, including BBC ‘Britain’s Secret Seas,’ BBC ‘Coast’ and two ZDF productions, ‘People of the Sea’ and ‘Reisenhai, Gentle Giants of the Sea’, a 50-minute documentary focusing on the basking sharks and our work. This was made to be over-voiced and has therefore been translated into many languages and has been seen globally. We make sure that the sharks are on the BBC news every season as well as regulary featuring on the BBC and local news websites. Articles have been written for Diver and Diver magazine.
This 10 year old girl, Iona, found one of our MK10 PAT satellite tags on a Scottish Beach in 2010. To her parents amazement she knew what it was immediately. We must be getting the message across! We have re-used this expensive tag 3 times now.
Manx Basking Shark Watch, The Manx Government and The Manx Wildlife Trust.
The Manx Government has been immensely supportive of the work of MBSW. The department of Environment Fisheries and Agriculture licenses our scientific work. In return all MBSW research is available to them so that informed wildlife management decisions can be made. Participatory planning and communication between MBSW, the Government, the Wildlife Trusts, Universities and NGOs has been excellent and cooperative. This has resulted in excellent research, tighter penalties for infringement of the tough basking shark protection laws in Manx waters and clear guidelines being issued for all water users and wildlife tourists during the basking shark season. The basking shark steering group includes Dr Fiona Gell, senior marine Biodiversity Officer from DEFA.
Both DEFA and the Manx Government Department responsible for tourism have provided a significant proportion of MBSW’s funding, despite the financial climate. It has also part-funded Eleanor Stone, Marine Officer for the Manx Wildlife Trust. She works with MBSW, doing our fin photo analysis as well as managing our summer volunteers and producing a network of coastal information posters and boards. These enable the public to better understand and enjoy the basking sharks and other marine wildlife seen from the Manx coastal path. Please help us to continue this successful project by considering sponsoring our permanent boat crew.
References:
Gore et al 2008: Gore Mauvis A. David Rowat, Jackie Hall, Fiona R. Gell and Rupert F. Ormond Transatlantic migration and deep mid-ocean diving by basking shark. Biol. Lett. doi:10.1098/rsbl.2008.0147 Published online
Hardman et al, 2011 BSc hons University of Plymouth: ‘Concordance of genetic and fin photo identification in the basking shark, Cetorhinus maximus, in the North East Atlantic’.
Hoelzel et al 1992: Hoelzel, A. Rus, Mahmood S. Shivji, Jennifer Magnussen and Malcolm P. Francis Low worldwide genetic diversity in the basking shark (Cetorhinus maximus) Biol. Lett. doi:10.1098/rsbl.2006.0513 Published online
Noble et al 2006: L.R. Noble, C.S. Jones, J. Sarginson, J.D. Metcalfe, D.W. Sims, M.G. Pawson Conservation Genetics of Basking Sharks Final report for Defra
Stephan et al 2011 Available at http://www.manxbaskingsharkwatch.com/uploads/Final_report_-_Sur_les_traces_du_requin_pelerin_-_Feb_2011.pdf
Stephan et al (2010) E. Stéphan, H. Gadenne, A. Jung, A. Lefranc, J. Hall, G. Hall, S. Bessudo, G. Soler, F.Royer, B. Calmettes (2010) Galway EEA 2010, Satellite Tracking of Basking Sharks in the North East Atlantic.
The Basking Shark Steering Group oversees Manx Basking Shark Watch:
Dr Fiona Gell: Senior Marine Biodiversity Officer DEFA,
Dr Richard Hartnoll, Chairman Marine Committee Manx Wildlife Trust,
Eleanor Stone, Marine Officer Manx Wildlife Trust,
Graham Hall, Voluntary Technical and Boat officer for MBSW,
Jackie Hall, Voluntary Coordinator MBSW.
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