The NZG houses a successful breeding group of Knysna seahorses, the most endangered seahorse in the world.
The National Zoological Gardens of South Africa (NZG) is privileged to house a number of Knysna seahorses, the most endangered seahorse in the world.
This enigmatic species is known from only three localities in the southern Cape - the Knysna, Swartvlei and Keurbooms estuaries. If these estuaries are not correctly managed and conserved, South Africa's only seahorse species may face extinction.
Successful breeding group
The NZG has contributed to the conservation of this endangered species by housing a successful breeding group. A number of enrichment projects have been introduced at the NZG's aquarium to help these magnificent, yet delicate, sea creatures feel at home.
The main objective for seahorse enrichment is to stimulate and encourage more activity in the tanks in an effort to mimic their natural habitat, to determine if the seahorses show any preference for a specific colour and to determine if they recognise the presence of other seahorses in the tank.
Artificial seaweed, mirrors, transparent plastic pipes and food were chosen as enrichment items. Three tanks were selected and used to compare behaviours. The three tanks are categorised according to the different sizes and ages of the seahorses.
Different materials stimulated activity in the tanks and the results showed that the seahorses prefer orange compared to the other colours used. The results also showed that seahorses are aware of the presence of "other seahorses" (their reflections in the mirror) in the tank.
The Knysna seahorse is a small, delicate creature with a mottled greenish brown colour, sometimes with scattered dark spots. Its neck arches in a smooth curve and its muscular tail is used to grasp a mate during courtship, or as an anchor to the substrate.
The seahorses showed a decided preference for orange objects. Here they inspect one of the transparent plastic pipes placed in their tank.
"Mirror mirror on the wall". A mirror placed in the tank indicated that seahorses are aware of other individuals in their tank.
Enrichment has proved to be an effective tool for encouraging different behaviour in our ex situ Knysna seahorse group and has revealed some amazing secrets of the ocean embodied by these fascinating creatures.
By Thobeka Ndlanzi, Aquarist, NZG
The National Zoological Gardens of
South Africa is a proud facility of
the National Research Foundation