Cetacean sightings around the Republic of the Maldives, April 1998

In April 1998, as part of a project to collect biopsy samples of putative pygmy blue whales (Balaenoptera musculus brevicauda) in the waters around the Republic of the Maldives, Indian Ocean, incidental sightings of cetaceans encountered were recorded. Using modified line-transect methods and handheld binoculars, a total of 267 sightings of 16 species of whales and dolphins were recorded during 20 at-sea days in the northeastern part of the atoll. Significant results include the following: (1) cetaceans were abundant and species diversity was high, including nearly every pantropical species of pelagic cetacean; (2) the spinner dolphin (Stenella longirostris) was by far the most common species encountered (56 sightings) and also had the largest mean school size ( = 50.3 individuals); (3) blue whales were rare; only four individuals were sighted; (4) a large concentration of Bryde’s whales (28 sightings in two days) was apparently feeding in nearshore waters; (5) this paper reports the first records for the Maldives of Cuvier’s beaked whale (Ziphius cavirostris), Blainville’s beaked whale (Mesoplodon densirostris) and the dwarf sperm whale (Kogia sima): the latter was particularly common (17 sightings); (6) the spotted dolphin (Stenella attenuata) was rare and almost always associated with yellowfin tuna (Thunnus albacares), spinner dolphin, or seabirds, as has been reported in the eastern Pacific and western Indian oceans

The Impacts of the 2004 Indian Ocean tsunami within the Maldive Islands

A post-tsunami field survey was carried out in seven islands within the Central Maldives Island Chain, approximately 6 weeks after the 2004 Indian Ocean Tsunami. The area studied had damage ranging from extreme to light, dependent upon proximity to the atoll barrier reef. We examined the island in order to document damage to structures as well as changes in the geomorphology and geology of the islands. We found that record of pervasive erosion that stripped corals and sands from the littoral zone and beach. The coral blocks were left in the vicinity of the back beach. The sand was washed over the islands (particularly on the islands closest to the barrier reef) and left a sand sheet, which generally did not bury the grass on the island, but did fill harbors...The drainback from the tsumani flooding and currents associated with the tsunami passage deeply eroded beaches on the lagoon side of islands. There was a net transport of sand from the islands, offshore into deep waters of the lagoon during the tsunami. There was heavy damage to vegetation adjacent to the beach, due to undermining and stripping of the vegetation and due to salt-water damage to vegetation. Tsunami inundation reached 1-3 m on these islands and the islanders reported that the wave came first from the east and then from the west and met near the center of the island. The water was reported to have retreated first, resulting in turbulent waters prior to the tsunami flooding. While a strong erosional event occurred in the Maldives Islands, it would be difficult to differentiate the traces of the tsunami from a storm deposits and it is likely that the traces of the tsunami will be entirely removed by normal coastal processes in a few years time, leaving little geologic evidence of this major tsunami event