After ten years of civil war on Sri Lanka, the members of the JBL research team were the first to be allowed into the north of Sri Lanka, occupied by the rebel Tamils. The destination was the untouched rainforests, rivers and streams. There are no natural lakes on Sri Lanka, instead huge reservoirs which have developed into a natural paradise. In cooperation with the well-known Sri Lankan ichthyologists, Professor Kotagama and Professor Silva, who also accompanied the expedition, we continued on foot, by jeep, raft, inflatable dinghy and on the back of elephants to the natural habitats of the fish and terrarium animals.
Unfortunately Sri Lanka is not spared the effects of climate change. After months of drought the rainy season started early. The streams and rivers became raging torrents, with a milky-brown liquid instead of clear water. Each river crossing became an adventure and everyone was worried about expensive equipment such as cameras or electronic measuring instruments. Together with local fishermen, roughly half of the native fish species were found. Precise water analysis of the locations and measurements of the speed of the water current give new insights into the successful breeding of fish species. Laws protecting native species limit or even ban the export of endemic fish and terrarium animals from Sri Lanka. Export is only allowed if the animals are bred. From the zoogeographical point of view, it is interesting to note that adjacent rivers do not have the same species of fish. All major river systems are separated by parallel mountain ranges, effectively preventing any mixing of fish species.
In addition to aquaristic reasearch, research related to the terrarium was also on the timetable: measurements of air temperature, humidity and the composition of the ground were carried out. Terrarium specialists Rainer Nagel from Kiel and Jürgen Weisbrod from Wiesloch were able to observe monitor lizards, mountain horned dragons, radiated tortoises and skinks.
1998 was a truly black year for the Maledives: the natural phenomenon known as El Nino caused above-average high water temperatures of over 30°C. This caused the death of algae (zooanthellen) living above all on rock coral, which usually led to the death of the coral. Known as coral bleaching, this process has become sadly notorious world wide. After staying in the rainforest in Sri Lanka, the JBL research team travelled to the Maledives to gather their own impression of the damage and effects on the ecosystem of the coral reef.
The result was shocking: all hard corals to a depth of about 10 m are practically 99% dead! The world-famous wealth of fish of the Maldives appears not to have suffered, however. Astonishingly all reef inhabitants are still to be found on the reef flat. This of course lead to the supposition that they obtain their food from the deeper sections of the reef which are not damaged. It is only to be hoped that these reef zones can withstand the increased demand for food in the long term without suffering damage! Huge shoals of fish are still to be found in the blocks of coral and under the overhangs. In the open water grey reef shark and black-tipped reef shark could be observed. Even if these elegant swimmers are not exactly popular aquarium fish, they are always fascinating to observe.
During the underwater feeding trials, the JBL team got a new member. A Napoleon wrasse, over 1 m long, joined the group and watched with interest to see if the various reef inhabitants ate the aquarium food products on offer. When a large moray eel stuck its head in the JBL MariPerls can, his patience came to an end. He snapped a whole can into his huge mouth and chewed on it until it until it was in shreds. It seemed to have tasted good, as he now swam from diver to diver, begging for cans. JBL is considering developing a special Napoleon wrasse food in bite-proof cans..... Light measurements with laboratory luxmeters to a depth of 25 meters yielded very interesting results. Below 25 m, however, the water pressure was so strong that the luxmeter casing (in an Ewa marine underwater camera case) gave up the ghost. Teamwork was called for when it was time to zone a fringe reef. A line was unwound 30 m deep from the shore to the end of the reef, with knots every 10 m. Each team member was responsible for a 10m section, on which all sessile organisms were identified and counted. The detailed results are to be published in specialist magazines shortly.