From Madagascar we flew to Mauritius in just under two hours. Our JBL importer Goolam had organized everything and, clearly pleased to meet us, he picked us up at the airport.
The next morning we went out to the sea in two boats for some diving. We wanted to see whether the islands looked different under water, even though they are situated in the same ocean and in the same region. We had two days with three dives each to get a picture of the situation. The water was much cooler than at Nosy Be/Madagascar: Instead of 28 °C only 25-26 °C. The coral growth was sparser and the abundance of fish was lower too.
The two wrecks Elmily and Waterlilly, which sank in 1981 and 1982, were especially interesting. The stone corals growing on the wrecks enabled us to clearly measure their growth rate. A maximum diameter of 40 cm meant the table corals at Madagascar were growing just over one centimetre per year! In an aquarium the growth rates of the Acropora species are much higher. However, the wreck lies at a depth of 25 m and therefore does not provide these corals with good living conditions due to the reduced light irradiation. The soft corals we likewise found, do not possess endosymbiontic algae which are dependent on light, and they were up to one meter high and absolutely fantastic. The water values we measured differed only in the magnesium content (1220 mg/l) from those of Madagascar. The pH (8.2), KH (8 ° dKH), calcium (460 mg/l), density (1.025) were identical.
The fifth part was a report on our nocturnal search for frogs: JBL Expedition Indian Ocean: part 5 - nocturnal search for frogs
The seventh part is about the Seychelles: JBL Indian Ocean Expedition: part 7 – the Seychelles