Category Archives: bottlenose dolphins

A visit to Watamu Marine Association

Last week the marine team were fortunate enough to go on a mini road trip and visit the Watamu Marine Association early on Friday morning. Watamu is a small village on the Kenyan coast which has pristine beaches and reef protected lagoons.

The Watamu Marine Association (WMA) was formed in 2007 with the vision of protecting Watamu as a natural asset and encouraging economic prosperity by promoting quality tourism primarily to benefit the local community.  It is a non-profit and voluntary organisation and its members include the local community, environmental sectors as well as tourism sectors.

Recently the International Fund for Animal Welfare (IFAW) started funding a dolphin conservation programme in Watamu, enabling the WMA to focus its attention on the welfare of the dolphins in the area. This programme will focus on community education and enforcing responsible dolphin watching protocols locally. Research will also be an important element of the project, the number of dolphins and the population distribution in the marine park and reserve will be studied.

The main purpose of our visit was to share information, skills and learn from each other and it was a great success… As GVI has been studying dolphins in Kenya since 2006 WMA can learn a lot from the challenges and initiative successes we have had in our dolphin research. In return, they have been working on a waste management programme and making crafts from recycled materials, such ideas are a great addition to the waste management improvements we have been implementing in Shimoni and are setting up in Mkwiro too.

Through collaboration, hopefully a national conservation plan for resident and migratory cetaceans in Kenya can be developed in the future. All of us thoroughly enjoyed the trip and spending some time with the fantastic team at WMA. They are in an exiting stage of the process and it will be interesting to see where they take it!

To find out more about Watamu and the marine association and some of their projects or to get involved visit their website or check them out on facebook.

Calving Season for Indo-Pacific Bottlenose Dolphin.

We had a remarkably successful first week of surveying for the 2011 expedition, with sightings total of 42 bottlenose dolphins within and around the Kisite Mpunguti Marine Protected Area KMMPA. They were seen in varying group sizes, the minimum being 2 and the maximum 16. What was most noticeable about these groups, however, was the composition. All of them had calves or juveniles present in the group, where many of our sightings lack juveniles or calves.  Interestingly, the calves all seemed to be fairly small in size, suggesting they were recent additions.

Indo-Pacific Bottlenose Calves

Indo-Pacific Bottlenose Calves

 Furthermore the number of sightings of calves seen in this first week of the expedition has been seemingly disproportionate to previous data, seeing a rise from around 7% in the first week of last expedition (October 1st-7th 2010) to the current figure of 22% of the groups being made up of calves.  In addition, we can compare this to the data collected at the same time last year where calves formed 13% of groups, there appears to be a significant increase in calves around this time of year.

The south coast of Kenya experiences a change in weather conditions from January to March, a season called ‘Kaskazi’ when the waters become much more turbulent. It is possible that groups with calves are coming in closer to land to seek shelter, or it may be that the turbulence has increased the nutrient content in the area making food more abundant. Whatever the reason, we will continue to monitor the composition of Bottlenose dolphin groups and analyse our sightings data in more detail to see if we can extract more patterns regarding peak calving seasons and calving intervals.

A Whale(shark) of a Time

So the morning was a little overcast, as we are moving into the “Short Rains” that’s not too surprising, and with the sea a little choppy we changed our plans for the day and instead of going out deep looking for spinner dolphins we decided to head to the more sheltered snorkel transect.

 

As we headed out to Kisite Marine Park and spotted a group of bottlenose dolphins near and around a tourist dhow. At the sighting we starting photographing for “Mark Recapture” so we were snap snapping away when suddenly Shafii our illustrious boat captain saw that the tourist dhow had something with them. “Something BIG” were his precise words, and we all started to get excited. Myself and Edita already at the front could see a large grey shadow like blur beneath the surface, and Shafii had spoken to the dhows driver who had confirmed our hopes. It was a Whale Shark!

 

A Whale Shark photographed underwater

A Whale Shark photographed underwater

 

As we got closer we realised just how big it was approximately 6-7 metres. And it was right there just off the bow to the boat. The whale shark is up to 46 feet (14 m), weighing up to 15 tons. The average size is 25 feet (7.6 m) long. It is the largest fish in the world and although the largest fish in the ocean they are not predatorial towards humans. This enormous shark is a filter feeder and sieves enormous amounts of plankton to eat through its gills as it swims. It has a huge mouth which can be up to 4 feet (1.4 m) wide. Its mouth is at the very front of its head not on the underside of the head like in most sharks.   

 So this individual whale shark wasn’t a giant for its kind, but it was certainly big enough for us! With our underwater camera we were able to lean over the side and get a little footage of the shark as he decided to leave. The shark wasn’t with us for long but it was long enough for a good photograph before heading off out into deeper water but although brief, as the first sighting of a whale shark for GVI since 2007 it was a heck of a sighting!

A marine mammal extravaganza

We were up early on Tuesday morning the plan being to first head into deeper water before cutting back across to Kisite Marine Park and to Transect 9. No sooner had we left the channel when a small group of bottlenose dolphins were spotted. We made our way over and managed to Mark Recapture them. This is the methodology we use and it means we photograph the dorsal fin of all the dolphins in the group and compare them to other fins  we have taken previously to see which dolphins are socialising with each other and there travelling patterns. We were really lucky today as we not only managed to get all of the dolphins on camera but we also got to see some tiny newborns and photograph them as well.

 

Photographed socialising Bottlenose Dolphins

Photographed socialising Bottlenose Dolphins

After observing their behaviour for nearly an hour we resumed our route into deeper water. Suddenly Shafii our captain saw what we had all been hoping for, a large spiralling jump in the distance. Spinner Dolphins! We headed in their direction as quickly as Bardan (our boat) would take us and before we knew it we were surrounded by a group of long snouted spinner dolphins some 70+ individuals strong. With cameras at the ready we began taking as many photos as we could of their impressive and unique spiralling jumps, as well as their dorsal fins for more photo identification. The large group were very sociable and stayed close to the boat jumping and bow riding for well over an hour before we had to end the sighting and head over to Kisite to do our snorkel transect.

A group of over seventy Spinner dolphins travelling south

A group of over seventy Spinner dolphins travelling south

When we reached transect 9 we all jumped in eager for a cooling dip in the crystal clear ocean and set off on the transect. Within 5 minutes we spotted a green turtle and 2 minutes afterwards we saw Transect 9 resident ‘Squirt’ a large hawksbill turtle who lives on the reef their. By the time we arrived back at base we had recorded an impressive 8 sightings of turtles 3 individual bottlenose dolphin sightings and of course the large and very memorable and rarely seen group of spinner dolphins. All in all an incredible dayon the boat and I have another 4 weeks to look forward to.

Humpnose Bottlebacks?

This is a follow up of the October blog about Indo-Pacific humpback dolphins (Sousa chinensis) and Indo-pacific bottlenose dolphins (Tursiops truncatus). A month after our last sighting of around 6 bottlenose and 2 humpback dolphins mating, we spotted a group of the same composition. After analysing photos of the two sightings it appears that these are in fact the same individuals.

 

Humpback and Bottlenose dolphins associating in Wasini Channel

Humpback and Bottlenose dolphins associating in Wasini Channel

Proximity between these species is not uncommon, but interactions between the two are rare in the waters around the Wasini Channel. With this group seemingly being stable, the chances of hybrid dolphins are a possibility. One thing is clear, these are actual “interactions” with the humpbacks amongst the group, as opposed to humpback dolphins feeding with or following the bottlenose. Studies in South Africa have also shown similar findings (Karczmarsky et. al 1997).

Potential for hybrids after this particular interaction!

Potential for hybrids after this particular interaction!

 

This latest sighting was in the Wasini Channel and the dolphins were travelling east. The sighting ended very close to the location of the October sighting. We will be checking our sighting photos closely for more evidence of interactions between these two species of dolphins as well as hoping for more chances to study them.

 

Johnny Zabari, November 2010

(Description of selected behaviours of humpback dolphins Sousa chinensis, some info obtained from Karczmarski et al. Aquatic Mammals,1997, 23.3, 127-133)

Dolphin mating near Wasini!

Recent sightings of Indo-Pacific Humpback dolphins (Sousa chinensis) have been few from both our research vessel and land watches. They are most commonly spotted between Wasini Island  and the surrounding coastal waters in Southern Kenya. These dolphins tend to avoid boats and are usually difficult to approach.

Indo Pacific Bottlenose Dolphin

Indo Pacific Bottlenose Dolphin

This all added to our surprise when we had a Humpback dolphin travelling towards us when we were in our boat (Squirrel). As it dived below our boat, even more surprisingly a bottlenose dolphin (Tursiops aduncus) surfaced in its place. We then had a bizarre encounter (for me) where we had two humpback dolphins and at least 5 bottlenose dolphins mating.. There were two pairs constantly mating while others were interchanging and also appeared to be mating. This included  what appeared to be moments where Humpback and Bottlenose species were mating. The frenzy of fins and foam around the dolphins made it difficult to count exact numbers. Unfortunately, we did not get any conclusive photo or video evidence of cross species mating.

Dolphins mating

Dolphins mating

The dolphins stayed alongside the boat, mating and travelling very slowly south-easterly. We left the dolphins to it and they continued to travel south, indifferent to our presence. This was an exceptional sighting also because our marine officer ( with over 15 years experience of dolphin research) believes there is a possibility that these could be hybrids, partly due to the ‘strange appearance of the dolphins’ (the bottlenose dolphin’s dorsal fin looked triangular, like a humpback dolphin).The dolphins also appeared to be smaller than a normal bottlenose.

Bottlenose and humpback dolphins are known to associate with one another, and we have witnessed them in close proximity before. However, this encounter appears to be something more unusual.

Some information taken from ‘Whales, dolphins and porpoises’ by Mark Carwardine, DK Publishing 2002.

Jonathan Zabari, October 2010.

Marine Surveys Reveal The Treasures Of The Sea

Excitement was high as we headed out with some new marine volunteers this week. With their training completed and a greater understanding of the work and marine mammals we were searching for, we hit the sea. Being my second week on the marine research programme, I was feeling more confident and at ease with the research methods and eager to get back onto the water.

Moorish idols

Moorish idols

We took a route up towards Funzi Bay to begin our search for dolphins. We were lucky enough to find a group of sixteen Indo-Pacific Bottlenose Dolphins (Tursiops aduncus) socialising. As we were away from the main tourist area, we were able to observe the dolphins undisturbed for 45 minutes. This allowed us to see some unusual behaviour and get lots of photographs that could be used later in photo identification of which individuals were present. When taking photos, we focus on the dolphins’ dorsal fin as this has unique and distinguishable marks and nicks that can be used to identify individuals and subsequently to analyse residency rates, social structure and associations between specific dolphins. This mid-morning sighting was just as remarkable for the more experienced members of the marine team as it was for the newbies, and we were all slightly entertained observing dolphin mating rituals, involving 3 dolphins!

One of the bottlenose dolphins performing a 'tail dive'

One of the bottlenose dolphins performing a 'tail dive'

Because of such high tides this week, we have been unable to return to Transect 9 to see if the six turtles we observed last week were still around; hopefully by the end of the week we will be able to, but until then we are happy snorkelling in the Kisite Marine Park with the stunning corals, sea stars and Moorish Idol fish. It’s always amazing to see the colourful angelfish and butterfly fish as they are indicator species whose presence indicates the health of the coral ecosystem and high biodiversity levels.

 With the expedition coming to an end, we will all be leaving with a better understanding of the importance of our oceans and the species that are dependent on them; it is critical this knowledge is spread and it has been so rewarding to know that we are all part of research and management initiatives that will help preserve and conserve the marine resource here for the future.

Twende is a Mother!

The GVI Marine team is happy to announce that TWENDE dolphin is a mom!

 

The mother - Twende ("let's go" in Kiswahili)

The mother - Twende ("let's go" in Kiswahili)

Twende is the number 004 of our catalogue and she is regularly seen by the research team socializing and feeding in the Kisite-Mpunguti Marine Park. She has never been seen next to a calf since the research  started in 2006 so we believed Twende was a male dolphin.

 

004 Twende_catalogue photo

004 Twende_catalogue photo

Pictures taken last week, on the 27th January 2010, show Twende next to a new calf! The two never separated during our 30 minute sighting, and have shown a lot of interaction such as rubbing and breast feeding.

Twende and her baby blog

Twende and her baby

 

For all of you ex GVI staff (this one is for you Sergi!) or volunteers that remember seeing Twende, current or future GVI volunteers, and all other dolphin lovers, we wanted to share this baby smile with you! Enjoy the pictures!

 

GVI Marine Team *

The Elusive Humpback

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.”
 HBD sightings

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.

 HBD spyhopping

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

A Blue Day

Yesterday we had an incredible blue day out in Marine. The days start quite early, by 6:00am we are all taking our breakfast, while the sun is still half asleep. At 7:00am we are already in the boat, searching for some animals in the blue pristine waters of the Kisite-Mpunguti Marine Protected Area.
Just as we went off, we saw this beautiful African Fish Eagle, just staring at the water, resting in a tree by the water. This big eagle is commonly found in this area and nests in high trees, especially acacias, figs or euphorbias and feeds mainly on fish, but also water birds and carrion.

a-fish-eagle-blog.JPG

The magestic African fish eagle (Haliaetus vocifer) 
After surveying the beautiful Funzi bay, we changed course and headed to Nyuli Reef and the Marine Reserve. In the shallow waters of Nyuli, we had another interesting sighting; two big green turtles were mating just about 30m from our research vessel. We turned off the engine and witnessed the courtship and mating behavior, while we recorded the coordinates on our GPS. Hopefully all went well for this pair and soon enough the female can lay her eggs in the sandy beaches of Funzi Island. Green turtles can lay more than 100 eggs, which take about 60 days to incubate and hatch. In Funzi, the Local Turtle Conservation Group, helped by KESCOM (Kenya Sea Turtle Committee), and GVI Conservation interns, patrol de beaches and provide environmental education to local people to help to conserve and protect this endangered species.

mating-blog.JPG 

 The mating turtles

turlte-head-blog.JPG

A turtle surfaces and is caught on camera
We continued our survey and headed to Kisite Marine Park, when we found a group of dolphins socializing and traveling. Excitement on the boat, while we grab our marine mammal sighting form, GPS and camera for photo-id. Some of the animals in the group are well known to the research team, such as chiizi, as well as two mothers and their calves. The water was so calm that we were lucky enough to see the calf breastfeeding under the water, just next to the boat. Wooohh! The mother and calf association in dolphins is very strong and the baby dolphins can breastfeed for more than two years. The mother’s mammary slits are located in either side of the genital slit.

mother-37-patsy-and-calf-blog.JPG 

 A mother (catalogue number 37 or “Patsy”) and her calf

patsy-and-baby-surfacing-blog.JPG

“Patsy” and her calf
 

The day went on and we decided to snorkel transect 9. As if it couldn’t get an better, we had two turtle sightings while snorkeling; one juvenile hawksbill turtle and one adult green turtle. This green turtle seems to be resident at this spot, since we have seen her over and over on transect 9. It is very easy to identify her, as she is missing the back right flipper. It might have been caught in a net or hit by a propeller while younger, but managed to survive and heal its wounds. Alongside with the turtle we witnessed the amazing reef fish variety of the Marine Park.

turtle-blog.JPG 

 The turtle spotted on transect 9
 

Hopefully, all the data GVI is collecting will continue to contribute for this ecosystem to maintain its unique characteristics and help to conserve its biodiversity for the years to come!