Science Centres: Aquatic Biodiversity and Biosecurity

 

NIWA scientists Aslan Wright-Stow (left) and Mike Scarsbrook (right) in Lost World (Mangapu Cave).(Photo taken by a cave guide from Waitomo Adventures)

In the dark and frigid waters of New Zealand’s caves there lives a diverse range of aquatic invertebrate species that can be classified either as troglobites – animals specially adapted to cave environments – or troglophiles – animals from surface habitats that have an affinity for cave systems.

Recent research by NIWA scientists in cave systems around Waitomo has led to a greater understanding of the distribution of these two distinct groups within the caves, and is helping to assess the potential effects of tourism and recreation use on cave biodiversity.

After a summer spent crawling through caves with evocative names such as Knee Wrecker Passage, the Organ Grinder and Cleft of the Orcs, we have shown that troglophiles, for example, mayflies or koura, are generally restricted to main streamway passages, whereas troglobites, for example, blind amphipods, tend to occur in smaller side passages. These results have implications for tourism and recreation use, because main streamway passages, the areas most frequented by humans, do not appear to have different invertebrate biodiversity from those of surface streams. In contrast, small side passages, where there is less human traffic, tend to have a more distinctive and hence potentially more sensitive fauna.

Our conclusion – that human foot traffic may not be affecting New Zealand cave systems as much as we once thought.