Archive for the ‘Research’ Category
Yesterday we went out tagging with Rachel Graham from WCS. We are going to put out accoustic tags in Kenya with Rachel in November. We met Rachel at the conference in Perth 3 years ago and it was great to meet up again after so long. Also on the boat was Rafael who is a representative from CONANP, Mexico’s national marine regulatory body. Rachel put out 2 accoustic tags, Rafael put out some streamer tags as well as taking biopsies and Volker took some amazing underwater footage of the sharks. I took pictures from the boat and had some fantastic swims with the sharks we saw. We also saw dolphins, 2 sets of mating turtles and hundreds of cow-nose rays which Volker managed to film which wasn’t easy because they were very shy and moving at an incredible speed. We will show you some of his video work when we get home next month. In the meantime here are some of my pictures. Here is Rachel about to take some photos of a tagged shark.
This is Rachel’s husband Dan swimming alongside the shark. Â It was incredible to see how the sharks feed mouths agape. The water was very clear on the surface but surprisingly murky (and cold!) once you got in. This is the jetty with all the whale shark tourism boats. There are a total of 140 licensed whale shark watching boats here on Holbox island and people come here almost exclusively to swim with whale sharks.
Rachel has made some temporary tatoos - here is a picture of Volker and me with our whale shark tatoos on
Tomorrow we will finish off working on our presentations for the conference which starts on Tuesday. We will continue to keep you all updated on our work here on Holbox island. Until then, all the best from Mexico!
Greetings after a long time!  Volker and I are finally here on Holbox Island 4 hours north of Cancun, Mexico. It was a lot of work but we managed to raise the funds to get here and as you can imagine it was a monster trip all the way from Diani Beach, Kenya. The conference starts next week and we are looking forward to it hugely. We will get a chance to present our work and show how much we have done since the last conference 3 years ago. It is exciting because we really have done an enormous amount! We also get a chance to meet up with all our whale shark friends and learn about what they have been doing in their parts of the world. It will be a fascinating global showcase of whale sharks research and conservation efforts. I promise to upload some photos to keep you all posted on this the 2nd International Whale Shark Conference in history. Thanks and do keep reading our blog! Greetings! News from our scientist Brent in San Diego - another of this year’s tags has popped up. Tag 80172 appeared a few days ago just south of the Kenya-Somalia border and has drifted steadily NE along the coastline. It is now near Ras Komboni, Somalia (a reported Al Quaida training area so Brent advises not to go chasing this particular tag just now). The tag appeared offshore jus a little north of Lamu and near Pate island. This tag was scheduled to come off in November (9 months after tagging on 22 February off Diani beach. We don’t know yet why it has popped off. It could have been taken off or the dart tip came off or the line was bitten through - the shark was at relatively the same depth for a while and sometimes this can trigger the early default release as well. We might get some clues when the data is all in and can be analysed properly. In any event, we will have 2 months worth of data on where this shark has been which is great news! Very positive Will keep you posted with any other developments. Have a nice day Sad news re the acoustic tagging expedition - we went out yesterday from 10am to just before 3pm and did not see a single shark! We had 6 hardy expedition members with us including staunch supporters from Nairobi and a journalist all the way from Kigali in Rwanda. Peter Zanetti was our pilot teamed up with David Kimtai our KWS spotter and Volker was all set to tag. It was very windy and overcast so the sea was quite rough and it was hard to see anything with the sun. It had poured with rain during the night as well and even though I had dreamt about seeing lots of sharks it was not meant to be. We sat out there on the churning sea for hours watching the plane go up and down but we only saw dolphins and turtles (not bad but not great when you are looking for whale sharks). Here is Volker giving a briefing and behind him you can see Gwili from the Colobus Trust who also joined us. Gwili’s mum has actually adopted and named the first 2 sharks that we tag with acoustic tags so although it was completely by chance it was very fitting that Gwili was on the boat with us for the start of the expedition.
This is a picture of the actual tags with some visual references for you thrown in for you to judge size easily.
They are amazingly small - the silver dart goes into the whale shark’s skin. You can also see that they are numbered and coded.
And here is a mournful sight - Volker’s spear gun with tag attached and fins close by - all set for him to jump in when the radio call comes in.
Sadly the fins did not touch water yesterday and the tags won’t be put out now until November at the earliest. I am really disappointed as I wanted to report on this when we presented our work to date at the 2nd International Whale Shark Conference to be held in Mexico in July. We have never tried tagging at this time of year but were of the opinion that unless we try we will never know more about our whale shark population. I was totally convinced that we would see whale sharks! Thank you to all the people who came down to support us, and hopefully we will have more success next time. We are glad that we tried because otherwise we wouldn’t have learnt what we did. Every little bit of research that we do really counts and helps us build a clearer picture of whale sharks in Kenya. It will now be a double celebration when we finally do put these tags out because we were so disappointed this time. Every donation we receive will also help us carry on with our work so please help us continue what we have started.
Check out these pictures of the last tagging expedition taken by Agnes on a disposable (!!) camera - I think they are great!!
Look at the beautiful patterns on this shark. What a marvellous creation!
That is a remora (sucker fish) next to the shark below.
A big thank you to Agnes for sending me her pictures. And, nice surprise, here is Brent tagging elephant seals - check out the East African Whale Shark Trust T shirt!!
 I still have some spaces left for the acoustic tagging expedition coming up this weekend so contact me if you are interested! Have a nice day folks!
Here is a picture of the tag from this year that came off after only a few weeks. This was the 3rd shark we tagged this year. We tagged it on 21 February and it came off on 3 March. As you can see if you look really carefully, you can see that about half the dart tip is sticking out.
I think we were having trouble with the pressure charge on the speargun about then which might explain why it didn’t penetrate deeply.   Brent had made notes in his log stating that he wasn’t sure that it was a good penetration, just from seeing how much of the tether was exposed when looking at it underwater.   In any event, it did stay on for about 2 weeks so we will get some data on movements and diving and of course a real plus on the recovery as we can use it again. Here are the GPS positions that helped us find it.
Fantastic news from France!! Our 2 tags have arrived in San Diego and they are now safely in Brent’s hands. They will be sent off for analysis and then stand by for ground breaking data and history making news! I am so relieved that they are safely with Brent. You always worry that such a precious cargo might get lost somewhere along the way…but Brent has just emailed to say he has them and we are delighted! Here is a close up of tag 66003, our famous year old tag.  Look how battered it is - almost like someone has tried to scrape off some bits…for now it is a mystery. We will learn a lot about this tag in the coming days but we will never know everything about its journey… Volker and I are in France and we send you bisou a tous!!
Here is the story in pictures of our tags trip to Europe. I carried these tags in my hand luggage like they were gold dust! Here they are in my hand luggage with my book and keys. Can you see how scratched and worn they are? The one that is really badly scratched is the one that has been on a whale shark for a year. It is well worn! You can clearly see the antenna, the high pressure foam bulb float which contains the pressure and temperature guages and then the main tube with all electrics including the battery and software then finally the light sensor which is the clear bit at the bottom which gives us info on ambient light levels. This allows us to determine dive depth, day, time etc.
This is a picture of the tags on my kikoy. A kikoy is a Kenyan type sarong. Check out www.kikoy.com for more info. I don’t go anywhere without mine.
Here is Volker holding the tags. I didn’t let them out of my sight and as soon as we landed I took them to the post office to send off to Brent. I won’t be able to relax until they reach San Diego safely!
I will keep you posted on their journey.
My name is Simon and I have been volunteering with the East African Whale Shark Trust for over a year now. This is the story about how we found the 2 tags. A few weeks after the the great Expedition 2008, I recieved the call from Nimu that two tags hadfallen off! I rushed to see Nimu and she gave me details as how to locate the tags in two locations on the North coast of Mombasa. We looked at the Google maps Brent had sent us with the GPS locations and Volker showed us how to use the GPS. I called David French who was then a volunteer with the Trust. The following day we took off to North coast to go find the tags. According to the coordinates we were given one tag was somewhere at Nature trail (bamburi quarry transformed into animal santuary). It was the adventure and we were happy to look forward to it! On arriving at the spot we were shocked to find out the coordinates were pointing at the tree! Somehow we were confused. We went on to look for the next on which was about 12 kms away. The funny thing was the GPS we were using directed us to the road which was access to the beach, but the same thing happened as with the first one. Frankly we were discouraged but we didn’t gave up.We put up posters everywhere in the villages where coordinates were close to. Then We headed back home. Two days later we had some more coordinates which the tags had transmited.The first tag showed that someone was walking with it! On arrival to the direction where the GPS was pointing it was at the beach but we didn’t have the access to it. So the only way was to  get permission from one of the homesteads next to the beach but it was not easy to explain to the  old man we met. David rushed with the GPSwhich was pointing that the tag was 30m away fro where were but the old man was furious with him for going through his compound. In fact he rushed and picked a machete to attack him! I cooled him down which was not easy. Finally he agreed to take us where the GPS was pointing at. On our way there we met two fishermen who agreed also to help us. On arrival at the spot we started to look for it and after 45min David found it Wow! We rewarded the two fishermen and the old man - they were happy especially the old man who apologised to David. Then we headed back to the first one. I started talking to the beach boys where the tag had transmitted first. David had rushed to Mombasa briefly. Luckily one of the beach boys told me that they had collected it and one of them had gone with it home hoping it was a torch but it was not working. I went with them but they kept on asking me what was the reward! I told them once Iconfirmed it was the one I will give them each 1000/- or USD 10. A few minutes later they brought it to me I couldn’t believe it was the one! I called Nimu and David! Once we believed the coordinates they were right. It was the adventure I will never forget.    Here is a picture of me with the tags we found! Â
Remember I told you about the whale shark that was sighted off Mafia island in Tanzania on February 16? Matt Potenski, the researcher in Mafia, has sent me these pictures of our whale shark and its tag!! He told me that it was seen near the surface at 1125hrs. It was a male of about 5.5 metres
What you can see is one of our yellow fabric tags albeit with a lot of algae growth but you can just about make out K001 in the middle. Matt takes neoprene gloves with him to clean the tags and he told me he uses his XL Cressi freediving fins plus a lot of puff to clean the tag off so that he can read it! He had to get back on his boat 4 times and be taken to catch up with this shark 4 separate times in order to clean the tag! He told me “I simply dive down and grab the tag - swimming fast enough to prevent any tension on the tag string and vigorously wipe the algae away”. What a star! He also sent us a picture of the shark which will be sent off for photo ID.
Look at all the little fish around it. Isn’t it beautiful? We were so excited to hear from Matt and are so grateful to him for sending us the photos. I had to post this on the blog even though we are about to board a plane in a few hours. I wanted to share these photos with you. Please let me know what you think! |
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Nimu Njonjo and Volker Bassen report daily on efforts to save the worlds largest fish. Join our marine research, tagging and following whalesharks in Diani Beach, Kenya.
