The Aliens Are Here

Why do we run? There is no simple answer.

There are a myriad reasons personal to each runner.

Common reasons are an appreciation for nature, the love of being outdoors in a natural setting, finding hidden places with beautiful soul-stirring vistas, and of course, the joy of sharing these with loved ones and like minded people.

But what if by simply passing through these beautiful areas, we are potentially contributing to their transformation?

This thought led to a study looking at the potential for trail runners to transport and introduce alien invasive plant seeds into protected areas.

It’s an important question, as globally, biological invasions are not only recognised as one of the largest threats to biodiversity conservation, but they alter natural ecosystem functioning.

This ultimately impacts the potential benefits we can obtain from these ecosystems.

For many years, protected areas were imagined as untouched places exempt from the change occurring around them. However, drivers of change, like alien invasive species, do not stop at a park boundary. Biodiversity losses as a result of alien species are a reality in protected areas.

Probably one of the bestknown impacts of alien invasive plant species is their impact on river systems.

The cost of aliens

Over 13 years (2002 to 2015), R590 million was spent within SA's national parks on alien plant management.