Lake Malawi
It is also known as the Malawi Sea – not surprisingly. When you stand on the shore for the first time, you can scarcely believe that it’s a lake. From Red Zebra Lodge we traveled by boat to Cape MacLear National Park. The team spent two full days there learning more about the habits of the fish. Day trips were made to an island in the lake where you can snorkel and dive.
The water was not as clear as you might imagine. Visibility was between 6 and 15 meters. You would also expect the temperature of the water to be higher in tropical Africa. It was only 24° C at the surface, sinking to only 21° C at a depth of 40m!
The initial dives were spent just observing. At first all the aquarium keepers were so fascinated to see “their†cichlids swimming around freely, that they couldn’t even think of research. Tests could only be started after a few dives.
Water analyses were carried out to document the parameters of the lake. The most astonishing discovery for some team members was that the water hardness was so low. With a TH of only 5° GTH and a CH of 7° GCH, this water hardness is exceeded by almost any tap water!
The higher CH is due to the soda sources in the north feeding sodium bicarbonate –rich water into the lake. Since sodium does not raise the TH, whilst bicarbonate increases the CH, the result is that the CH is higher than the TH. These water properties can be recreated using the JBL product AquaDur Malawi/Tanganyika.
On land the terrarium experts investigated light measurements. Interesting results were produced using UV-meters and luxmeters. Just one leaf reduced the UV radiation practically to zero!
A luxmeter was also used underwater. Protected in a watertight casing for a video camera, one diver held the equipment next to his depth meter to show the second diver the depth. The second diver noted down the depth and lux level on a waterproof writing pad, which was later evaluated on board the boat.
Feeding trials underwater were a special experience. Different sorts of food were tested for acceptance. The team members watched in fascination as the Mbunas (periphyton-eating cichlids) snapped greedily at the JBL Granulate. Aufwuchs or periphyton refers to the algae grass which covers all rocks to a depth of a few meters. Aufwuchs consists not only of algae and blue-green algae, but also of microorganisms living in the aufwuchs. An investigation of the aufwuchs showed that it seldom consisted of green algae, but more frequently of blue-green algae (Cyanophycea)!
Tests with green feed granulate showed very different behavior: the fish tried it, but did not eat it as greedily as food containing fish protein. The explanation for this was revealed to the team on another dive. One diver observed a whole shoal of Mbunas attacking a fish carcass. So the fish like the taste of fish protein very much, but normally don’t get any. Over the course of evolution, Mbunas have adapted to eating periphyton (mouth shape, teeth) and exploited a habitat which does not offer any nutrition to the predators in the lake. But if the rare opportunity of fish protein presents itself, they don’t say no!
All photos have been taken with analogue Canon mirror reflex cameras (EOS 1V und EOS 3) in carbon underwater casings from BS-Kinetics. Films: Kodak Extra Color 100 ASA. As flash equipment Subtronic Mega was used. Lens: Canon EF 100 mm Makro USM, Canon EF 20-35 mm USM, Canon EF 28 mm 1:1,8 USM, Sigma 50 mm 1:2,8 Makro and Sigma 14 mm 1:3,5. For differing focal lengths the corresponding front-ports for the underwater casings were used.
Facts
Reisorganisator Zuid Afrika: Boleng Adventures,
Wolf Snykers, www.boleng.co.za
Reisorganisator Lake Malawi: Safaris Afrika, Walter
H. Peters, Tel.: +49-30-3137744
Reisperiode : September
2006
Reisprijs: 3600,- € van en naar Frankfurt. Deels zelfvoorziening.
Deelnemers
Heiko Blessin, gedipl. bioloog, Expeditieleider JBL, Duitsland
Dr. Ludwig Neurohr, doctor uit Rhens,
Duitsland
Cees Dijkers, eigenaar dierenspeciaalzaak uit Zaandam, Nederland
Jürgen
Weisbrod, eigenaar dierenspeciaalzaak uit Wiesloch, Duitsland
Thomas Oehrl,
eigenaar dierenspeciaalzaak uit Untermerzbach, Duitsland
Janet de Sousa, sera
Importeur uit Johannesburg, Zuid Afrika
Falk Lehmann, eigenaar dierenspeciaalzaak en duikinstructeur uit Eggenfelden, Duitsland
Hartmuth
Koschorke, terrariumspecialist en groothandelaar uit Karlsruhe,
Duitsland
Monika Tintelott, gespecialiseerde dierenwinkelassistent, uit Schauenburg, Duitsland
Klaus Tintelott, aquariumviskweker en fabrikant van aquaria uit Schauenburg, Duitsland
Michel & Sophie Comte, JBL importeur uit Martigny, Zwitserland
Johannes Mecke, eigenaar dierenspeciaalzaak uit
Berlijn, Duitsland
Rainer Nagel, terrariumspecialist uit Kiel, Duitsland
Thomas John,
Distributiemanager dierenspeciaalzaak uit Berlijn, Duitsland
Norbert
Nicolaus, eigenaar dierenspeciaalzaak uit Güsten, Duitsland
Accommodation
Aliwal Shoal :Cutty Sark Hotel,
Scottburgh, zuidelijk van Durban aan de zee.Duikcentrum bij het hotel:
Quo Vadis Dive Charters, www.raggiecave.com
Hluhluwe-Umfolozi
Reservaat: Mpila Camp in het reservaat.
Hermanus:
Windsor Hotel aan zee.
Cape Region: Simonstown, Quayside Hotel
bij de jachthaven .
Cape Town: City Lodge aan de waterkant.
Lake Malawi: Red Zebra
Lodge, Stuart Grant Fishfarm, www.lakemalawi.com
Activities
White shark tochten in Kleinbaai, Brian
Mc Farlane, www.sharkcagediving.net
Walvis spotten vanuit de Gansbaai, www.whalewatchingsa.co.za
Shark
school met Andy Cobb in Durban: www.SharkProject.com
Shark
school met Dr. Erich Ritter: www.sharksch ool.com
