Tag Archives: focal-group scan sampling

Behavioural Surveys Begin!

Numerous studies have been carried out throughout the world to access the impact that boat activity has on the behavior of bottlenose dolphins.  These include locations such as Clearwater (Florida), Hilton Head Island (South Carolina), Shark Bay (Australia) and off the south coast of Zanzibar.  The studies have come to show that various boating activities do have an impact on dolphin behavior such as causing changes in activity, movement and dive patterns.  They have also proven that the abundance of dolphins present in a pre-selected site has been negatively affected with such activity.

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Boats in Kisite 2009-08-27 ds01-028 

GVI have recently introduced a new survey to the marine programme in which we will investigate the effect of boat interactions with Indo-Pacific bottlenose dolphins within the Kisite-Mpunguti Marine Park, Kenya.  The methodology adopted by GVI is the same as that used in Zanzibar, in which they investigated the behavioural changes of Indo-Pacific bottlenose dolphins in response to boat-based tourism.  In order to do this GVI devised a data sheet to capture two sets of information.  The first relating to the number of tourist dhows present, the distance they are from the group of dolphins and whether they violate the guidelines and secondly to record the behavior of the dolphin group; activity, spread within party, movement, dive type, party speed and direction.

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Feeding 2008-10-16 394

The behavior and associated data of the dolphins is sampled every fifteen minutes using focal-group scan sampling.  To do this all individuals within the group are continuously scanned for the first five minutes (ensuring at least three scans), and the dominant behavior is determined and recorded.  The dominant behavior is that which more than half of the group are engaged in at the sample time.  The remaining ten minutes of a sample period, referred to as the lag-phase, is used only to record the number of tourist dhows within a distance of less than 50m from the dolphin group and to indicate whether they are violating the guidelines.  This process is repeated every fifteen minutes for as long as possible. 
The behavioural studies are part of the Socio-economic impact of the dolphin-watching industry in Kisite-Mpunguti Marine Protected Area project. The objectives of this project are to collect information about the socio-economic impact of tourism operation on the area and to analyze the sustainability of increased levels of human-dolphin interaction.