The Dugong, Dugong dugon, in Egyptian waters: distribution, relative abundance and threats

Abstract

This paper presents the results of an interview survey used to identify the distribution and relative abundance of Dugongs (Dugong dugon) in Egypt’s Red Sea during 2001, 2002 and 2003. The survey area ranged from Hurghada, immediately south of the Gulf of Suez, to El Shalatin, about 200 km north of the Sudan border. Respondents, such as fishermen, were asked preprepared questions to determine the number of Dugongs observed per sighting, the length class of individuals, the month of observation and the location. Important feeding habitat, defined in part by the presence of Dugong feeding trails, was identified during a concurrent seagrass survey. Dugongs occurred throughout the survey area, but apparently in very low numbers. The maximum and minimum numbers reported were 17 in 2002 and 12 each in 2001 and 2003. Some individuals may have been counted more than once per annum. There was no evidence of annual change in the number of Dugong sightings, but a statistically greater number of sightings was made in summer compared with winter. Two hypotheses are proposed to explain this variation, but they are not mutually exclusive. The first is that Dugongs undertake winter movements to warmer waters. The second is that winter sea conditions made it harder to observe Dugongs. Important feeding habitat in the Wadi El Gemal Hamata Protected Area was confirmed by the presence of Dugong feeding trails in seagrass meadows. Known and predicted threats to this species in Egypt are loss of seagrass meadows, net entrapment and boat strikes.