At first sight there doesn't seem to be much connection between satellites, sophisticated technology and river dolphins swimming around in some of the most rural and inaccessible parts of Pakistan. But technology was crucial to the success of WWF-P's recent survey of Indus River dolphins and their habitat. WWF - P's Geographic Information Systems Laboratory provided support to the dolphin survey team at all stages of the expedition.

A Geographic Information System is a powerful computer facility for storage, analysis and presentation of environmental data. Its strength is its ability to combine descriptive information such as number of dolphins or presence of juveniles with spatial information such as geographic location or distance from the river banks. This allows people to better understand the relationships between different types of data. The power of spatial information is aptly described by the Chinese proverb "A picture paints a thousand words".

How the Geographic Information System was used in the dolphin survey:

Planning

Satellite pictures acquired for the survey show the Indus River at low water levels in Nov/Dec last year. These pictures were initially used to help plan the survey, by showing the number and location of side channels and measuring the length of each section of the river. Because the satellite pictures revealed an extensive network of side channels, the team decided it was necessary to have a support boat to survey them.

Navigating

Maps were produced for each river section, combining the satellite picture, location of villages and a latitude and longitude grid. An example of these maps can be seen on the facing page. These maps were a valuable navigation tool for the survey team. Global positioning system (GPS) receivers were used to pinpoint the boat's exact location, which could then be traced on the maps, allowing the team to determine how far they were from the next town or side channel.

Recording

GPS receivers were also used to record the exact place where each dolphin was seen. Each sighting and the observations made at that location have been entered into a database. This valuable data will allow researchers to carry out a detailed analysis of the distribution of dolphins along the river.

Analysing

An example of the way survey data can be used is in the calculations of the density of dolphins in each stretch of the river (spatial analysis). For instance, the number of dolphins seen between Chashma and Taunsa barrages is 84. A GPS receiver on board the survey boat recorded the exact distance traveled as 270 kms, so it is easy to calculate that there are 0.3 dolphins/km in this section of the river. Below Taunsa to Guddu barrage the density is much higher, at 0.75 dolphins/km.

Another example of the way the Geographic Information System can be used is the help it can give to researchers looking for an answer to one of their most interesting questions: Where do the dolphins spend most of their time? Do they prefer the deep, fast-flowing channels, or protected water near sandbars or islands? By combining the researcher's won observations with GPS locations and satellite pictures of the river, they will be able to find an answer.

Presenting

Results of the dolphin survey are summarized in the map in the previous article Tale of a thousand dolphins. This shows the distribution of dolphins along the Indus River, and the distance traveled between barrages. This ability to present key information clearly and concisely is an important component of the Geographic Information System's contribution to WWF - P's conservation effort.