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June 2010 
Inside this issue ...
Holiday courses!
Culture comes to the vultures
Urban biodiversity?
Dr Emily Lane wins award
Director's comment
New arrival at Emerald Animal World
Stringent measures protect King penguins
NZG staff master penguin conservation skills
Maintaining an inland marine aquarium can be challenging!
First genetic assessment of pangolins in SA
Outbreak of deadly primate disease controlled
NZG hosts wildlife medicine courses for vets
ZooClub members investigate SA's biomes
Conservation Grapevine
World governments fail to halt biodiversity loss
Lions targeted for Chinese 'medicines'

 
The National Zoo's aquarium houses endangered species such as the Knysna seahorse.
 
The NZG's Charity Ndlanzi monitors water quality.
 
Records need to be kept on a daily basis to monitor the aquatic environment.
 
Feeding the NZG's aquatic collection can pose a challenge.
 
Salts used for artificial marine water preparation.
Maintaining an inland marine aquarium can be challenging!

Charity Ndlanzi, Tracy Shaw, Abeda Dawood and Dolf van den Doel, Department of Collections & Conservation, NZG

The National Zoological Gardens of South Africa (NZG) has the largest inland marine and freshwater aquarium in the country.

The challenges involved in maintaining the NZG aquarium are mostly related to its age (established in 1974), its size (3 000 m2), and its large variety of species (215 species of fish, five species of invertebrates and 16 species of amphibians).

Within the marine section there are 75 species of fish and invertebrates which include endangered species like the Knysna seahorse (Hippocampus capensis) and ragged-tooth sharks (Carcharias taurus). These are housed in large marine tanks with a total capacity of 101 055 litres.

Artificial marine water is prepared in a 8 360 litre mixing tank at the aquarium using a special salt mix formula. The total cost of salt mix used per year is R120 000. To reduce costs, the NZG mixes its own artificial marine water and biological filters are to be installed in all tanks to reduce changes in the artificial marine water.

As the aquarium runs a closed water system, water quality needs to be monitored very closely. The water is tested on a daily basis for all parameters and the required levels are maintained through water changes. The NZG needs to have permit from the Tshwane municipality for the disposal of aquarium water due to the volumes and salinity of the water.

With the NZG being 600 km away from the Indian ocean and 1 400 km from the Atlantic ocean, collection and transportation of marine species can present a challenge. The NZG is working to overcome that via the use of appropriate transport tanks and aerial transport, when required.

Marine fish species are difficult to breed. To meet this challenge, the NZG has a network of partners for augmenting its fish collection and for swopping larger specimens for smaller animals when these grow to large for their enclosures.

The production of food for its aquatic animal collection can also be problematic as the main food staples - brine shrimp and daphnia populations - are difficult to maintain throughout the year. The NZG is addressing this by using frozen food as an additional or replacement food.

As challenging as it may be, the NZG aquarium has undergone a positive transformation to ensure that SANS (South African National Standard) Zoo and Aquarium practice and African Association of Zoos and Aquaria (PAAZAB) standards are met in the management of the NZG's collection. The critical success factor in the transformation was the NZG's partnership with other institutions such as Two Oceans Aquarium, uShaka Marine world, East London Aquarium, Port Elizabeth Aquarium, the Department of Environmental Affairs and our regional zoo association, PAAZAB.

For more information, contact Charity Ndlanzi at charity@nzg.ac.za.