GVI Kenya

Category: Cetacean research, Dolphins, Kenya Wildlife Service, Kisite Mpunguti MPA, bottlenose dolphins | Date: Oct 14 2009 | By: gvikenya

Kisite-Mpunguti Marine Protected Area (KMMPA) lies south of Wasini Island (south-coast of Kenya) and covers an area of 39 square kilometres. The KMMPA includes the National Park surrounding Kisite Island and the Marine Reserve surrounding the Mpunguti islands. The KMMPA and the marine wildlife it contains are an important tourist attraction and, as a result, an important resource for Shimoni and surrounding communities. The islands within the KMMPA are surrounded by coral reefs attracting divers and snorkelers to the area. Almost every day dolphin-watching companies operating from Shimoni travel through Wasini Channel to the KMMPA. These tourist dhows most frequently encounter Indo-Pacific bottlenose dolphins (Tursiops aduncus), and less frequently, Indo-Pacific humpback dolphins (Sousa chinensis).

Global Vision International (GVI) Kenya’s main working partner is the Kenya Wildlife Service (KWS). The research conducted by GVI is shaped to satisfy the objectives of KWS, so as to assist them towards better management of the area.  All data collected thus far is made available to KWS to aid in management plans of the study area. The Marine Programme is supporting KWS to collate data by conducting vessel surveys, which was focus on assessing the bottlenose dolphin abundance on the area, during the initial phase.

After three years of cetacean research in Kisite-Mpunguti MPA, GVI has estimated the absolute abundance of bottlenose dolphins around 122 individuals, being the second biggest population of Indo-Pacific bottlenose dolphins (Tursiops aduncus) in East Africa. The largest population of the species inhabits in Kizimkazi (south-coast of Zanzibar), and holds between 139 and 179 individuals (estimation made by University of Stockholm in 1999-2002).  

Photo-id and mark-recapture methods were the methodology used on both studies to get the estimation. Photo-ID refers to the identification of individuals by distinctive features (shape, outline, natural markings and scarring) of their dorsal fins, flanks and flukes. Some scars will be retained through life, whereas others will be added and may fade through life. The depth and severity of the wound will determine the length of time this may be used for identification. These features allow known individuals to be re-sighted. The re-sighting rate can be plotted on a discovery curve, the plateau of which suggests population size. Photo-ID can also be used to determine residency and demographic data such as inter-birth intervals, patterns of ranging and mortality.

Mark-recapture methods are used to calculate population size from the proportion of known individuals re-sighted over the study period. Mark-recapture models estimate only the size of marked individuals in the population. Therefore, the total population size has been corrected by the correction factor.

Kenya Wildlife Service applied a code of conduct in 2007 for the tour operators to follow when manoeuvring around the cetacean species; unfortunately it is not being fully adhered to as it has only recently been implemented. The levels of interaction between cetaceans and the tour operators are not being monitored or regulated in any way. The impact these activities may be having is unknown. In particular, it’s not known whether current levels of dolphin tourism are sustainable for the area. The first estimation of Indo-Pacific bottlenose dolphins in KMMPA will allow GVI and KWS to measure the levels of tourism impacts, analysing the population dynamics of this species.

Tags: absolute abundance, coral reefs, correction factor, demographic data, depth, divers, dorsal fin, identification, Indo-Pacific bottlenose dolphins, inter-birth intervals, Kenya, Kenya Wildlife Service, kisite island, marine programme, marine reserve, mark-recapture, mpunguti island, national park, photo-ID, severity, shimoni, snorkellers, south coast, surveys, University of Stockholm, wasini channel, wasini island

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Category: Cetacean research, Dolphins, Kisite Mpunguti MPA | Date: Sep 07 2008 | By: gvikenya

Working on a Sunday isn’t always a bad thing… with tourism still recovering, we are taking every opportunity to join the tour boats and collect research data, so I set off at 8 this morning for a day of dolphin surveys. Towards the end of 2007 we expanded our dolphin research to incorporate the tourist boats that take visitors to the Kisite Marine Park. Whilst our core research enables us to assess population size and social associations, studying the interactions of the tour boats with the dolphins is equally important in enabling Kenya Wildlife Service to manage tourism responsibly and ensure that impacts on the dolphin population are regulated.

With their kind co-operation, we boarded the Dolphin Dhow tour, to record data on the location, duration and dolphin individuals encountered. It was a beautiful sunny and relatively calm day… no one was complaining about giving up their Sunday. As we approached Kisite Island, we joined a couple of other tourist dhows that had come across 11 Indo-Pacific bottlenose dolphins, including a mother-calf pair and a sub-adult, travelling in a tight formation towards the Kisite reef.

After the launch of the dolphin-watching code of conduct a year ago, and with five tourist boats in total, it was pleasing to see them all drive responsibly, following the group from behind at a distance of about 30m, so as not to disturb their behaviour. This is particularly important when there are young dolphins present. After 15 minutes two more tourist boats joined us with another four adult bottlenose dolphins bow-riding to join the group. The behaviour then changed, with peduncle and tail dives, and more scattered distribution suggesting that they had started foraging at the edge of Kisite reef. It was a fantastic opportunity for tourists and our research team to observe these wild animals with the sub-adult giving us a couple of playful leaps and tail slaps on the water’s surface to keep us all the more enthralled, and a soundtrack of rhythmic gentle blows as they exhaled at the surface.

As the dolphin group reformed and set off travelling again, Dolphin Dhow moored up their boat on the edge of the reef to give us the opportunity to cool off and enjoy the underwater world. After two and a half years working here, today was one of the best snorkeling trips, with exceptionally good visibility and a diversity of colourful reef fish that I hadn’t witnessed before, of all shapes and sizes… including some of the biggest I’ve seen.

Then it got better… we were unexpectedly joined by four of the dolphins, swimming around and beneath us. One of the most valuable regulations in the code of conduct was to prohibit explicit swimming with dolphins. The common anthropomorphic view is that dolphins are ‘friendly and enjoy human company’, and we all too easily forget that we are in the company of wild animals. Pursuing wild dolphins to get close enough to drop people in amongst them has to impact on their natural behaviour and it is believed to cause stress or interfere with their feeding or socialising. It really is comparable to driving off-road in a terrestrial park to get close to lions - something that few responsible tourists would tolerate these days.

However when the dolphins choose to come to you, it is at least a voluntary response to your presence, and an exceptionally rewarding experience. For 5 minutes we had clear views of these beautiful, and surprisingly large, wild animals, swimming with easy grace and precision. And the sound of their echolocation clicks reverberating through the water and seemingly through your body as they approached head-on was astonishing. It is an innate desire to observe and understand behaviour in animals that keeps me endlessly enthralled by the natural world and makes every day in the field a new experience. So to be in the water looking down on the sub-adult as it rolled on to its back for two adults to rub along its belly, was an unparalleled privilege.

After a wonderful swahili lunch on board the boat, bobbing on the Indian Ocean, it was very difficult to feel sorry for myself for having missed out on the Humpback whales a few days ago… today was another one of those “I love my job” days! With special thanks to Dolphin Dhow for making it so.

Tags: code of conduct, dolphin research, dolphin-watching, Indo-Pacific bottlenose dolphins

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