GVI Kenya

I was sitting outside the cottage discussing the different types of hornbills found in Kenya, as a Trumpeter Hornbill had just flown over head, when Sergi (the marine officer of expedition 094) pulled me aside to talk about my independent project. I was secretly chuffed that I got given the one I did, as there was a choice of three. The title of my project was “Data Analysis of Indo-Pacific Humpback Dolphins (Sousa chinesis) collected by GVI Kenya Marine Team from 2006-2009.”
 

These animals are very shy animals and are not as well known as the bottlenose dolphins. Maybe because they are shy or perhaps because of their habitat distribution, there is very little data available. So this was a great opportunity to be able to provide some information. The GVI Marine Team has been collecting data on them since 2006. Whilst out on the boat on a survey day, if we have a spotting we follow them around, taking photos and also monitor their behaviour. Using a GPS (Global Positioning System) we are able to plot the route taken by the dolphins that day.  This allows us to see the areas where the humpbacks dolphins feed, rest, socialise, breed etc. As well as being able to gain data on group sizes and composition.

 So I went forth and did some research on our friends the humpbacks and also plotted the information on our study area (see picture) which is the Kisite-Mpunguti Marine Park and Reserve and the surrounding area.
 Humpback dolphins occur in small groups (3-7) and are distributed throughout Indian and Western Pacific oceans as well as the coast of south east Africa. Inhabiting tropical and subtropical waters (15oC – 20oC), they prefer coasts with mangroves, rocky reefs, estuaries and lagoons. Typically found in waters less than 20m depth, they only venture a few miles from the shore line (as shown on the map), and occasionally they swim up rivers. The distinctive hump on their dorsal fin gives rise to their name; and they are medium sized 2.5m – 2.8m.
 

boat trWasini channel and the surrounding waters are prone to quite a lot of boat traffic and fishing. Humpbacks tend to avoid boats, although marks caused by propellers have been observed. This is a concern not only because of the damaged caused to the dolphin but also because of the resultant change in their behaviour, e.g. leaving the area. Another concern is that being situated on the coast; the communities living here depend upon fishing as a resource. Recent efforts have been made to educate some of the local community as to the importance and implications of over-fishing and pollutants.

It is my aim to develop a catalogue of the humpback dolphins, as this will allow us to determine population numbers and residency rates in this region. This is a technique called mark-recapture, and it uses the dorsal fins to identify each individual, mostly from the notches made by other dolphin or boats, but also by the shape, colour and size of the fins. Plus, on the cheeky side I will get to name some of them!

Sarah Watson was a conservation intern on 094 Expedition, and is currently doing her work placement with GVI, as staff member on the Marine and Terrestrial Programmes

Hello everyone!

I guess to start with we should mention that today is Wednesday… Weetabix day! Yeah!
Small things that help remind us what day it is as time flies when your having fun! So, after our weetabix and powdered milk we were ready for a full day out in the bay.

We had originally set our course for the South East Section of the Kisite-Mpunguti MPA where we had plans to do some research and turtle snorkelling on transect 9. To get there Shafi took us out into Funzi Bay, beyond Nyuli Reef where the water starts to get very deep, 200m and in some parts deeper.

 Spotted dolphin

This is the perfect place to see Spinner dolphins we all thought. After exiting the channel and the shallower reefs without seeing any bottlenose dolphins, hopes were high for the Spinners. There were a couple of close calls that led to nothing and then randomly, Shafii found a strange red thing floating in the water. As we approached it, we found out that it was a survival suit that must have been thrown overboard off a Chinese cargo ship a few months ago. Things like that you don’t usually expect to see while surveying dolphins, let alone the one pant leg that looks mysteriously ripped off!

After concluding that it must have been caused by an engine propeller, we were off again… and soon after this, the real magic happened…

We continued towards our South East direction when we first spotted them (no pun intended!) At about 100m from the port side at 20 degrees was the first of 3 sightings of dolphins today. Although you never get tired of seeing them, this may not have seemed significant, however…

Today was a very special day for the crew onboard Bardan, for GVI and for dolphin research in Kenya as we had the privilege of seeing the first documented sighting of the Pantropical Spotted Dolphin in GVI history and possibly in Kenya also. A great experience to be apart of, we tracked them for about an hour and noticed that a mother had a new born calf. Always a great sign of a healthy population.

This species is well documented in the Eastern Tropical Pacific but is not studied anywhere else. It is a medium to large dolphin that in some respects looks similar to the bottlenose but with the key distinguishing feature of spots and mottling along its body and its extremely falcate dorsal fin.

 Group of spotted dolphins

After we left them, I felt really privileged as it was one of those treats that make you really glad to be here. A real sense of pride and accomplishment that you have contributed to the cause that is aimed at protecting these very animals and their habitat.

Thanks to everyone for making it possible!

By: Tristen Murchie

Today we chugged our way along the coast of the Shimoni peninsula all hoping for an exciting day to finish off the marine research week. Not long after leaving the Western end of the Wasini Channel our hopes were fulfilled when Shafii sighted Indo-Pacific humpback dolphins just off the coast. First contact was with a mother and calf but shortly afterwards we spied another group about a hundred metres away and so headed off to check them out… and were rewarded with a group of twelve to fourteen humpback dolphins literally frolicking in the shallow waters.  

Humpback dolphins are meant to be ’shy’ but this group were anything but as they spy-hopped, breached, swam around the boat and generally showed off, posing for the paparazzi on the boat.  Most excitingly, there were four mother and calf pairings – baby humpbacks are particularly cute with their little humps and tiny dorsal fins and they gave our two photo-identification photographers plenty of opportunities while the rest of us ooh-ed and aah-ed at the display. It can’t be a bad day when you are sat on a boat in the sunshine watching a group of dolphins at a time of day when you would normally have been arriving at the office to start work! We had a spectacular snorkel in the warm waters off Kisite Island then spied a turtle swimming on the surface as we headed back to base.  

As I mentioned before, the Kusi winds and rain make life difficult for dolphin research on the open seas. Yesterday our efforts on the water went unrewarded again… although I stick with my little mantra that “no data is still valuable data”!

Today however the team aboard ‘Lampard’ started with a promising early sighting, a group of four bottlenose dolphins sighted around the eastern end of Wasini Island. But the rough seas made for tough conditions under which to follow the small travelling group, let alone try to take the photos from which we would be able to try and identify the individuals.

So the search continued, rounding the end of Wasini Island in to Mpunguti marine reserve, cruising between the two Mpunguti islands and on in to Kisite marine park. The destination was Kisite Island where we hoping that the sheltered side would allow us at least to look for turtles in the water along one of our snorkel transects.  However before we ready to jump overboard, another group of four bottlenose dolphins approached the boat as the wind and waves subsided… leaving us with good conditions and a perfect opportunity to get back to what we had been trying earlier, photo-identification.

Besty with her distinctive dorsal fin notches 

Both Andy and Jamie were armed with cameras in a photo-ID duel. It was the two adult dolphins that were our key target, as they would hopefully be individuals catalogued over the past 3 and a half years that we could recognise. And in fact they both were, Nene (or individual 083) and Besty (individual 017 – the 17th individual we formally identified, from 2006). Besty was accompanied by her calf and the fourth individual was a sub-adult. With the local dolphins having been elusive for much of the last few months, it was pleasing to enjoy these four showing off in the calm waters around Kisite Island. The calf in particular seemed to be in playful mood, posing for the camera with ’spyhops’ – holding the head vertically out of the water.

 Nene with Besty’s calf spyhopping

No turtles on the transect, but the day was far from disappointing and seeing Besty again is like meeting up with an old friend.

Low tide amongst the mangroves revealed hundreds of tiny male and female fiddler crabs scuttling between little holes in the sand. The aim of our day though was to attempt to clean up some of the mountains of rubbish that travel the Indian Ocean currents from as far as south east Asia, to wash up on the East African coastline, trapped amongst the mangroves here on the southern shore of Wasini Island having floated through the Kisite Marine Park. Seeing all the cool little creatures that make the mangroves their home was an added bonus!

The open beach, exposed by the receding water, was so covered in small gastropods (and occasionally hermit crabs in shells they had commandeered from the gastropods) that we could not set foot on it for fear of crushing a delicate little home, and had to content ourselves with watching a group of yellow-billed storks through the trees. The male fiddler crabs put on a bit of a show for us and performed a strange sort of Mexican wave display with their one large claw; whether this was to try and attract the ladies or warn off others we weren’t quite sure.

All along the tide line seaweed intermingled with broken pieces of plastic, glass bottles, plastic bags and bottles, toothbrushes and flip flops. A five by ten meter path along the beach yielded five bin liners of rubbish and a bucket of glass, which was all we could carry back with us. It would take an army to clean all the debris that collects here from other parts of the world, and even then you’d be left with the feeling that just as much would be deposited after the next high tide. Walking back to base under the strain of our rubbish bags did, however, leave us with a small sense of achievement and as they say ‘every little bit helps’!  

Keziah gives us the news from yesterday’s marine research:

I woke up 6am in Shimoni, waiting to find out when the boat would come to pick me up at the jetty. With the rainy season, start times of marine surveys become a wee bit unpredictable – with one eye on the rain clouds you just have to wait for the opportunity! However, the sun was shining, there was no sign of rain and a phone call later I was jogging through Shimoni village to the boat.

We headed out towards Funzi Bay, across Nyuli Reef and to Upper Mpunguti Island when we had our first sighting of dolphins, something that has also become less predictable with the season. At first we thought there were eleven Indo-Pacific bottlenose dolphins, but soon realised this was an underestimation. Ten on the port side, ten on the starboard side, we didn’t know quite where to look, excitedly swapping sides with a chorus of gasps and squeals from our team, and splashes and blows from the dolphins.

Several individuals were identified immediately, including one of my favourite pairs; Besty and her calf. I had the pleasure to be on the boat when we spotted Besty and her newborn calf for the first time, adorably small with the foetal folds still showing! Others including Twende and the yet to be named individual ‘063’ were also identified.

The group were at first travelling fast in a southerly direction, then their pace slowed, with a couple of individuals approaching the boat to bow ride. This enabled us to get good shots of the dorsal fins, which will be used for photo-identification in our mark-recapture study. Unfortunately we also noticed an adult and juvenile that appeared skinny compared to the rest, with their ribs visible. We hope this wasn’t a sign of illness in the population or lack of food in the area… After taking enough photos we left them to continue south to the open sea.

The dolphins had done us a service, leading us to the start of the snorkel transect our survey leader had selected for the day, by Kisite Island… and it turned out to be the perfect day to pick this transect! As we climbed out of the water to board the boat post-survey, everyone’s face was an absolute picture: 3 hawksbill turtles, 5 green turtles and 1 moray eel! Ruth and I even had the pleasure of watching one of the green turtles swim slowly to the surface, stop for a few seconds and then continue to raise its head out the water, beak open for a gasp of air. This was closely followed by us both surfacing and giggling hysterically with joy having witnessed a behaviour in full that we had only seen before from above the surface as a turtle’s head appear and disappear in a second!

With the weather being on our side, we decided to return towards Funzi Bay again, but the sea was just a little too rough, so we diverted in to Wasini channel. Within 5 minutes of turning the boat around there was a shout from Katalin at the front, “DOLPHIN”, followed quickly by “HUMPBACK DOLPHIN!”. We had to wait 10 minutes for the individual to reappear, a very large Indo-Pacific humpback dolphin that seemed curiously darker than usual. We put this down to the glare of the sun, and waited for what we thought was a lone individual to resurface.  Then two individuals surfaced riding a wave, both smaller than the first. Several more minutes of waiting and we were shocked to see not only the three individuals from before, but another two adults and calf!

We continued to watch them for 20 minutes as they were feeding, coming up for several breaths before peduncle dives took them under for several minutes.  After surfacing for the third time, in unison, they formed a compact group, changed direction and headed south, crossing the channel towards Wasini Island. We were able to compare the colouration of the first individual and yes, he was distinctly darker, not something we had seen before. The mother of the calf had a deep scar around her neck, possibly from a fishing line. Only 2 weeks ago an individual was spotted with a huge chunk out the back of his dorsal fin, the shape suggestive of a boat propeller injury. Both these wounds emphasize the humpback dolphin’s vulnerability to fishing activities, boat traffic and marine debris around coast lines. But fortunately also an ability to recover from significant injury.

All in all it was quite an epic day for our research team and for me one of complete brilliance!

It doesn’t happen as often as I’d like with so much else going on but yesterday I joined the marine research team, 6.30am departure aboard our research vessel ‘Lampard’, on calm waters with the rising sun to warm us…

I take the tiller, captaining the boat east out of the Wasini channel, the rest of the team assume positions for dedicated watch. Passing the coastal forest of Shimoni I spot a colobus in the canopy and an African Fish Eagle… but today is the marine research programme, and it’s dolphins and turtles that we search for.

Rounding the south-east corner of Shimoni peninsula we enter Funzi bay, hoping to spot Indo-Pacific humpback dolphins that favour these near-shore habitats. No sign of them today. We pass a green turtle, but sadly a recently dead one floating at the water’s surface. No obvious cause of death, but this time of the year, during the kaskazi winds (the NE monsoon winds), seems to bring a peak of turtle mortalities each year.  Much of Funzi bay is shallow and doesn’t leave us much room to manouvre so we turn the boat around and head south, towards the continental shelf and open water. A flock of terns dives persistently at the water’s surface but the fish shoal they target has gone unoticed by any dolphin.

A more distant splash and a suspected dolphin sigthing, something dark and rounded surfacing. Half-way there before it becomes evident it’s another dead turtle bobbing at the surface. A huge one this time, a hawksbill, it’s been dead for longer and given the size it reached, somehow a sadder loss as we circle around it and continue our route south.

Sergi, our marine research officer takes over from me at the stern as I join the rotation of observers up front, each with our 45 degree field of view to patrol. Tom calls out a potential dolphin far ahead, an apparent leap and splash, Sergi steers us toward the point on the horizon and we keep scanning the surface. We rotate positions, both Tom and I looking forward, he sees something again, but is disappointed when there’s no following dorsal fins or repeat splashes.

Still we head further south, further from the shore and are rewarded 15 minutes later by 4 dorsal fins breaking the water’s surface ahead. They approach the boat to ride the bow and a further 3 dorsal fins join them. We expect them to be Indian Ocean bottlenose dolphins out here, but the small triangular fins, the smaller torpedo-like bodies and the long narrow beaks all point to something different. Three tone body colouration as they surface confirms we have found a small group of spinner dolphins.

Sergi hands me the camera, I try to get photos of the dorsal fins of each one as they sruface to breathe. It’s not as easy as it seems it should be. Unpredicatable quite where and when they will surface as they dart across the bow just below the surface, the angle has to be right, the sun behind, sharp focus… and you have to be quick. Sergi uses the time to talk the team of observers through the dolphins’ behaviour. Close to the surface, regular slow shallow surfacing, no obvious directional travel; they were probably resting. We leave the small group and within minutes an apparent lone individual further away leaps from the water, an acrobatic spin that gives them their name. Then 10 dorsal fins surface to our right. We barely get through counting them when at least 20 fins appear on the right. Our group of 7 was actually part of a larger group, in the end we estimate 40 to 50 individuals.

Spinner dolphins are thought to be seasonal visitors to this part of the Kenyan coast, possibly crossing the channel from Pemba, following the food with the kaskazi. In previous years we have recorded them between mid-February to mid-March, in large active groups (up to and over 200) off the shelf, south of the MPA. This kaskazi we had one sighting in December, and then last week. We do not think that this season represents any ‘break from the routine’ but more likely that our new research vessel gives us a higher, clearer viewing platform, and survey routes take us further from shore so we simply see more. The real exctitement is that we are now understanding more about these seasonal visitors; their ’season’ is longer than we first thoguht, and they are using habitats east of the MPA for resting suggesting they may be here for more than just quick foraging forays. Ironically, the fact that they are consistenly recorded outside of the marine protected area is not of too great concern. They are free from disturbance by the dolphin-watching tourist boats and in the absence of commercial fishing activities are not threatened here by high levels of accidental deaths from by-catch that plague some of their open-ocean counter-parts through industries such as tuna fisheries which are yet to be quite as ‘dolphin-friendly’ as we might be lead to believe.

I’ll keep you posted throughout our ’spinner season’…