Page 27 - Landscape SA 96

ENVIRONMENTAL FEATURE

investigate environmentally-friendly and were sent out through Rand Water’s a substantial and direct impact on
humane methods to sustainably manage internal communication systems. indigenous floral and faunal populations
the dassie population, and to prevent an and on an ecosystem’s biodiversity. As
escalation in a potential human-wildlife Dassie numbers and habits were also the country’s urban population numbers
conflict situation. studied by placing camera traps in escalate at an alarming rate, the pressures
strategically selected areas. A student from on natural environments and resources
A literature search and discussions with UNISA was on site once a week for a year increase. Awareness campaigns that
knowledgeable experts concluded that a to observe and record dassie movements address the importance of environmental
sustainable and humane option would be and behaviour. conservation can be invaluable tools in
to limit access to the dassies’ favourable preventing the destruction of ecosystems
resources such as shelter and food. In The dassies’ response to the team’s and biodiversity.
doing so, it was hypothesised that the deterrence strategies was varied. The
dassie population would reach a natural olfactory deterrents and blocking of pipes The natural environment is made up of a
and more manageable equilibrium. and other office infrastructure were the complex web of interconnected systems.
most successful approaches. The number By removing one component of this web,
Various non-lethal strategies were of dassies immediately surrounding the the entire system becomes disrupted
implemented in stages to allow for an building dropped by 67% in areas that and will not function efficiently. All living
assessment of which strategies would had been blocked off with fencing, while organisms, humans included, rely on these
contribute the most to reduce the dassie placing deterrents in the corridors reduced systems for food, clean air and water. It is
impact. Access to office infrastructure, such dassie activity significantly. important to recognise the importance
as car parks and pipes, was blocked with of nature and a balanced sustainable
fencing (Phase 1). Olfactory deterrents However, adding irritants to plants did landscape, while understanding the needs
were placed in areas identified as ‘high- not deter the dassies at all. Everything in of humans too.
use’ by dassies – these deterrents included the plant plots was eaten, regardless of
bowls of cotton wool balls soaked in whether it was coated with chilli or pepper Rand Water is committed to ensuring the
peppermint oil and eucalyptus oil, and powder or not. The presence of dogs on conservation of the natural environment
moth balls (Phase 2). Olfactory deterrents site also had no long-lasting effect. While through sustainable development
were replaced and refilled daily where they caused an initial scare among the initiatives such as the managing of the
required. Predatory simulations were set- dassies, they realised that the tethered dassie population at its Rietvlei site. Dassies
up, where trained dogs and their handlers canine offered no threat to them and they provide an important source of food to
patrolled the site over a number of weeks began watching the movement of the dog predators such as raptors, snakes, jackals
(Phase 3). Irritant deterrents (Phase and his handler from the safety of their and Verreaux's eagles. Removing them
4), which included capsicum powder, rocks. completely from the environment could
szechuan pepper and chilli powder, were have dire consequences for the efficient
applied to plants in demarcated plots. Responses from the staff surveys showed functioning of associated ecosystems.
that while damage to infrastructure
It was especially important to engage with and smelly middens were considered a For more information on the dassie
the staff on site to better understand their problem, the majority of respondents population management initiative at Rand
ideas and thoughts on dassies and their felt positively towards the dassies and Water, please contact Samanta Stelli at
behaviour. This process was undertaken preferred humane methods of control sstelli@randwater.co.za or 011 724 9371.
prior to any interventions and during the such as prevention of access to habitats Rand Water would like to thank the EMS staff
intervention phase. Online surveys were to manage populations, rather than on site for assisting with research aspects, as
run, face-to-face information sessions eradicating or removing them. well as the UNISA team for undertaking the
were held and staff were encouraged to research with diligence. LSA
chat about their experiences. Posters were Human-wildlife conflict, especially in
put up on site and information snippets urban and peri-urban areas, can have

The dassie population on site, their Dassie excrement around the head office building has caused damage and gives off
movements, habits and behaviour, very unpleasant odours
were studied by placing camera traps
in strategic areas

Landscape SA • Issue 96 2020 25