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MANX BASKING SHARK WATCH 2010:
Report by Jackie Hall: Maps by Eleanor Stone.
INTRODUCTION: This is a brief round up of what Manx Basking Shark Watch (MBSW) achieved in 2010, the public sightings scheme, the science and the media coverage.
This basking shark has a characteristic split dorsal fin. It is number 8 in the MBSW ID catalogue, part of the 'basking shark passport scheme'. The photo is a still captured from underwater polecam video footage by Graham Hall
The Manx Basking Shark Watch research team did a lot despite the fact that because of the windy weather and rough seas this was a very poor year to see basking sharks. This is not obvious from the numbers reported here until you know that, for the first time, we had an expert team of volunteer biologists, nick-named ‘The Dolphineers’ doing dedicated watches’.
Eleanor Stone, Marine Officer for the Manx Wildlife Trust, coordinated the excellent group of full-time volunteers who worked with us in the summer of 2010. They became known as 'The Dolphineers'. Some of the 2010 'Dolphineers', from left, Hannah Keogh, Kerry Froud, Clare Preeble and Niki Clear looking out from the house they rented in Peel. What a great crew! Hannah and Niki have joined us again in 2011
Sightings were difficult but the new basking shark ‘passport’ scheme established that we had at least 87 sharks visiting Manx waters in 2009/10. This passport work included DNA work from skin swabs. Previous satellite tagging work was put through rigorous analysis by the French scientists from APECS.
The ‘Britain’s Secret Seas’ team from BBC2, BBC Northwest news and French film-maker Yannick Cherrell filmed Manx sharks and the work of MBSW in 2010. This is always good news as nothing spreads the word about the need for shark conservation better than TV.
SATELLITE TAGGING: The tagging work is very expensive at £3500 per tag (including satellite time and data processing) but it gives us (and hence world governments) vital information about where they go and what they are doing.We have 3 tags to deploy during 2011. One came from Tower Insurance, one from last year’s Manx government funding from DEFA and one is the recycled tag already used twice. Tower insurance have very kindly given us £1,500 towards the data processing of these tags. We intend to deploy them on either very large sharks or very small ones. No-one has ever tagged a basking shark of less than 3m. We need to find out what the all-year round habitat selection looks like in small sharks as compared to the larger ones. We would very much like to have another shark go a very long distance as ‘Tracy’ the Tower Insurance shark did during 2007, when she crossed the Atlantic in 82 days. As she was a very big 8m long shark we are thinking that maybe it’s just the very big ones that do this. Hence trying to tag another big one or two.
You may remember that during 2009 we worked very closely with the French team of scientists from APECS (Association Pour L'Etude et la Conservation des Selaciens) Eric Stephan and Armelle Jung came to work with MBSW to put 5 of their tags on. Armelle's husband Sylvain sailed their large sailing vessel Parsival from France to do the work in the Isle of Man. Yannick Cherrel, a French wildlife film-maker came to film the work. His film was seen on French TV and is screened every day in the Oceanopilis Aquarium in Brest. The data retrieved from all the 8 MK10PAT satellite tags put on sharks in Manx waters and 2 in French waters has been processed by Eric Stephan of APECS. The excellent and very interesting results will be published shortly.
The MK10 PAT satellite tag that was put on a large male basking shark nick-named TONY was found on St Medans Beach, Dumfries and Galloway by Iona, aged 10. Her parents Sid and Caroline did an excellent job of tracking us down as our phone number had worn off. Wildlife Computers managed to download a full data-set from Tony’s 76 day journey around the Irish Sea AND to refurbish the tag so that we will be using it again in 2011. This will be the third time that this tag has been re-used. It was previously retrieved from a beach in Scotland having been found by a very good dog called Milly. One that occassion it had been on male shark so it is serving us very well.
Refurbishing a tag that has been recovered costs us just US$800 compared to £2000 to buy a new one so we are always very happy when one can be re-used. The data is being processed by Eric Stephan of the French APECS team.
Here is a photograph of Iona holding the tag. It certainly looks in very good condition. Very well done and thankyou, you deserved the £200 reward!
FILM CREWS: All film work is done under license from DEFA
The well known BBC‘OCEANS’ team came to film our Manx Basking Sharks in July. They particularly wanted to film MBSW taking DNA skin swabs from the basking shark’s dorsal fin.
Paul Rose, Frank Pope and Toonie Mahto
Their presenters Paul Rose, Toonie Mahto and Frank Pope came together with a full team of underwater and topside film crew.
Frank Pope and an underwater cameraman approach a basking shark to film with a pole camera:Photo Donal Griffin.
This genetic work is being done as part of a collaboration between MBSW, Dr Lesley Noble of Aberdeen University, Dr David Sims of the MBA Plymouth and Prof Mahmood Shivji from America’s NOVA. The excellent TV program was screened in May 2011 as the first in a series of 4 programs called ‘Britain’s Secret Seas, Giants of the West. We were delighted that our Manx sharks had nearly 12 minutes of prime TV time. They did an excellent job of calling for world-wide protection of basking sharks.
A BBC cameraman interviews a grey seal in Peel Harbour: Photo Donal Griffin.
Yannick Cherrell, the French wildlife film-maker came back again this year and successfully filmed basking sharks and grey seals for a French documentary.
Yannick Cherrel filming grey seals in Manx waters.
BASKING SHARK PASSPORTS: So what are basking shark 'passports'? They are a way of establishing the identities of individual basking sharks so that we can identify an individual again and again over the days, months and years. The Manx Basking Shark Watch public sighting scheme has been operating since 2005. It provides excellent information about where most of the basking shark sightings courtship activities are but may give a very misleading idea about how many basking sharks there are. This is because one shark may be reported many times at one of its appearances at the surface or from day to day, year to year and so on. Individual shark IDs will solve this problem and allow us to estimate the true number of basking sharks visiting Manx waters. It will also allow us to see how long individual sharks stay in Manx waters, which other sharks they associate with and whether they come back year after year or only every few years.Basking sharks are an endangered, protected species. To aid responsible management the Manx government and Manx Basking Shark Watch would like a reasonable estimate of how many basking sharks are visiting Manx waters. In order to achieve this we decided to give each basking shark a “Basking Shark Passport’. For this we need to know its sex, to have a length estimate, HD still photos of the right and left dorsal fin and to obtain a genetic skin swab.
This work requires a huge team to make it work. The Happy Jack team take the fin photos and collect and label the DNA, Les Noble’s team at Aberdeen University analyses the DNA, Eleanor Stone analyses the fin photos and one of the dolphineers keeps the photo catalogue up to date.
MBSW started this program in 2009. By the end of the 2010 season we have a total of 86 whole or part sets of data on individuals. The fin photographs are the key to re-identifying individuals on many occasions without disturbing them unduly. Only 37 of the animals identified had excellent fin markings but another few years of collecting this information should see a reasonable estimate of the real numbers of sharks visiting Manx waters. Although it will be fascinating to find out how many individuals visit Manx waters over the years it will be even more interesting to see whether individuals visit year on year and whether they stay for long periods within a year. It’s all very exciting. One of these individuals was seen in 2008, 2009 and 2010. Twenty six of them were seen repeatedly within one year and 8 of them were seen in more than one year. One individual was re-identified 5 times.
Graham Hall on Happy Jack, the MBSW research boat. Note the scrubby pad on a pole. The black smear on the pad is basking shark slime that he has just obtained by gently rubbling the pad against the shark's dorsal fin. This skin slime contains cells with DNA in them. This is analysed by genetic experts. The genetic 'fingerprint' will re-identify the shark at any time for the whole of the rest of its life.
WILDLIFE MARINE VOLUNTEERS: 'THE DOLPHINEERS'.
Over the last 10 years more
and more marine work is being done under the umbrella of the Manx Wildlife
Trust (MWT). To our delight Eleanor Stone was appointed Marine Officer a few
years ago. She has made a huge difference to all matters marine but it soon
became obvious that even more skilled, enthusiastic workers could be easily occupied!
For the 2010 summer season Eleanor recruited a group of wonderful volunteers
who soon became known as ‘The Dolphineers’.
They are mainly graduates or final year students looking for experience in Marine Conservation issues. The 2010 Dolphineers were Niki Clear, Hannah Keogh, Kerry Froud, Clare Preeble, Donal Griffin and Angharad Davies.
The 2010 Dolphineers relaxing after a hard days work. From left, Donal Griffin, Tom Felce of the Manx Whale and Dolpin Watch, Eleanor Stone, Marine Officer for the Manx Wildlife Trust, Clare Preeble, Niki Clear, Chris, who works in the pub, Angharad Davies and Alex, he was doing a dissertation on crabs.
They
rapidly became an essential part of the marine scene. They had many roles. One
of the main ones was doing effort based watches all round the Manx coastline,
looking for basking sharks, porpoises, dolphins, whales, birds and anything
else interesting.
Niki Clear and Hannah Keogh doing an effort based watch overlooking the Calf.
The Manx Basking Shark Watch research boat Happy Jack found
them indispensable as part of the crew. They came on board and took HD still
photos of the dorsal fins, took notes and learnt a lot about how to study
sharks and boathandling.
Hannah Keogh, Jackie Hall and Niki Clear on the Manx Basking Shark Watch research boat Happy Jack. They are holding 8 basking shark DNA samples to go to Dr Lesley Noble at Aberdeen University and Professor Mahmood Shivji in America.
They also helped with the MWT’s tide-pooling sessions
and Marine Weekend marine wildlife touch-tanks. As many as 100 members of the
public turn up to the tidepooling and more than 5000 to the touch-tanks so their help was invaluable. Eleanor
got some of them involved in the grey seal identification project and they
worked with the bird warden on the Calf’s Bird Observatory for a while.
Niki Clear holding a baby razorbill on the Calf .
They got involved in many other aspects of marine work. They
also took analysed photographs and input masses of data and attended marine incidents in the field.
Donal Griffin taking notes about a stranded harbour porpoise while Eleanor Stone and Laura Hanley of the Manx government's Department of Environment Food and Agriculture (DEFA) hold their breath! The animals was dissected for blubber thickness, stomach content and level of parasitism. This is done to try to establish the cause of death and state of health and nutrition of the porpoise at the time of its death. Picture taken 26/08/2010.
This was all excellent
experience for them and a great help to the work of the MWT. Two of them, Niki
Clear and Hannah Froud have come back in 2011 so they must have enjoyed it. Thankyou
dolphineers!
CONFERENCES: Jackie and Graham Hall and Eleanor Stone attended the European Elasmobranch Conference. It was held in Galway, Ireland, in November. The volunteer Dolphineers, having worked so hard for the project this year, also attended. Eleanor deservedly won the ‘Best Poster’ prize for her excellent poster presentation about the basking shark fin ID carried out in 2009/10.
The European Elasmobranch Association Meeting was held in Galway, Ireland in 2010. From left Eleanor Sone, Graham Hall, Jackie Hall, Kerry Froud, Hannah Keogh, Clare Preeble, Donal Griffin, Niki Clear and Tom Felce. The only Dolphineer missing is Angharad Davies.
PUBLIC SIGHTING SCHEME 2010:
- 410 reports of 1 or more sharks were received. Thankyou and well done.
- The first sighting of the year was, as expected, in the middle of the month on May 14th. We had 100 sightings in May. This was undoubtedly due to a few warm, settled days in May. May was good in 2009 as well, probably for the same reason. This may show that they are normally here in reasonable numbers in May but more normally feeding lower in the water where we cannot see them. The relatively calm seas brought them to the surface in numbers earlier than might be expected.
- As usual June (129 reports) and July (110) reports were the best months but unsettled, windy weather made for a relatively difficult season for shark watchers.
- The total count was that 947 individual sharks were spotted and reported so approximately half the number of sightings compared to 2009 despite a team of dedicated spotters being at work for the first time. Remember that this is very misleading as the same sharks are seen again and again. The MBSW fin ID work DESCRIBED EARLIER is helping us to assess exactly how many sharks actually visit Manx waters and the numbers MAY turn out to be very small, maybe less than 100 individuals.
- We had 7 reports of newborn sharks of less than 2m.
- We had 13 reports of sharks leaping clear of the water (breaching). 1 in May, 5 in June, 5 in July and none in August. This is MUCH less than usual and this is not surprising as breaching is often associated with other kinds of courtship behaviour and the MBSW research boat recorded NO courtship behaviour in 2010. The only possible courtship group turned out to be just feeding in a dense plankton patch just north of Peel, no intense close interactions of the kind typical of courtship being seen amongst them.
- Largest group was 14 individuals who were off Contrary Head all morning on 26th of August. We often see these larger gatherings towards the end of the season.
- Average group size was 2.3 individuals.
All MBSW sightings 2010: Each dot represents a sighting report, not an individual. There were 410 reports of basking sharks in 2010. Although it is not apparent from this map, when you compare it to maps from previous years the sightings are more concentrated further north, towards Peel. This was a little frustrating for the MBSW research team as the research boat Happy Jack is based in Port St Mary in the south of the Island.
MBSW basking shark sightings for May 2010: There were 100 shark reports in May. They follow much the same distribution pattern as you might expect, with a spread from Port St Mary to Off Peel.
MBSW basking shark sightings for June 2010: There were 110 basking shark reports for June. There are surprisingly few reports from south of Niarbyl compared to other years. This was very frustrating for the MBSW research team aboad Happy Jack as the boat is based in the south of the Island, in Port St Mary. This meant a long search every day before we found any sharks. This was a real phenomenon, not because no-one was looking. Happy Jack did surveys around the south including around the Calf and the Dolphineers did cliff-based effort based watches in the south so it wasn't because no-one was looking!
MBSW basking shark sightings for July 2010: There were 126 shark reports in July. Again, they are mostly around Peel with a few in the south, far fewer than we would normally expect for July compared to previous years.
MBSW basking shark sightings for August 2010: There were 58 shark reports for August. This is much as we would expect compared to previous years.
MBSW basking shark sightings for September 2010: There were 16 shark reports in September. Some years there have been only 1. The last shark report was on September 28th.
When you look at this graph it is important to remember what a poor year for shark sightings this was compared to other years. As is normally the case June and July were good but so was May. The May sightings were at the very end of the month as usual.
It is only when you look at this map, comparing all the years 2005-2010 that you realise what a poor shark-sighting year 2010 was. 2010 is all the orange bars. In many ways one should ignore 2005 as this was the first year of the public sightings scheme and not many people reported their sightings because they didn't know about Manx Basking Shark Watch. Each report is a sighting. A sighting may be one shark or a large group. As you can see in the graph below.
Looking at the graph above gives you some idea of how many sharks are in sighting report. As mentioned earlier the largest group was 14 individuals who were off Contrary Head all morning on 26th of August. We often see these larger gatherings towards the end of the season. The average group size over the whole 2010 season was 2.3 individuals.
The orange bars on this graph shows the number of individual basking sharks reported in 2010. It is important to remember that this does not represent a true analysis of how many sharks visited Manx waters in 2010 as many of these reports will be repeats reports of the same shark being seen again and again. This is why we started the Basking Shark Passport scheme, so we can better estimate how many sharks visit Manx waters every year and how often those individuals come back and how long they stay. It is still well worth people reporting EVERY shark sighting they see, however. This is because different people see different aspects of behaviour and some people get great photographs. This brings great benefits to the overall picture of how a year was.
As you can see people are getting to be much less keen to even try to give size estimates. This is a shame. I think it has happened because the MBSW research boat HAPPY JACK is making more accurate estimates against the length of the 6m long boat and the public are realising that they were over-estimating shark lengths. They are very difficult to assess but we still really appreciate them so please keep them coming!
MANY THANKS TO OUR SPONSORS:
MBSW is run primarily by volunteers but it still needs money for boat running costs and for scientific equipment such as satellite tags and cameras. We rely on sponsorship from a wide range of places and persons. On behalf of the basking sharks we would like to thank all our generous sponsors. 2010 saw some very generous sponsorship from Sea World Busch Gardens, The Manx Lottery Trust, the Manx Government (Department of Agriculture, Forestry and Fisheries and the Department of Tourism and Leisure), Tower Insurance Douglas, Dennis Drummond, The Good Gifts Catalogue Charity (via Prof David Sims) and Jill Ivens.
As volunteers under the auspices of a charity we are always very good at making a little money go a long way but because of the economic downturn we have been extra careful to make full use of every penny and we didn’t do a lot of things that would have been possible, in case we got no further funding in 2011.
SUMMARY All in all it was an amazing year. Please keep the reports coming in so that we can continue the good work. Many, many thanks to all of you who contribute to Manx Basking Shark Watch. We could not do it without you!
Written by Jackie Hall: Coordinator MBSW
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