Science Centres: Aquatic Biodiversity and Biosecurity

Isla Fitridge retrieving a settlement plate.

A settlement plate.

Isla Fitridge, a key member of NIWA’s Marine Biosecurity team, recently spent 3 weeks in Maryland, USA, working alongside staff in the Marine Invasions Laboratory at the Smithsonian Environmental Research Center (SERC).

Scientists there have been using passive surveillance techniques to monitor aquatic invasive species patterns at 21 sites in continental USA and Alaska and 2 sites in Australia for more than 3 years. Their data are being used to determine the geographic range of the country’s national fouling communities and provide synthesis, analysis, and interpretation of invasion-related patterns in the USA.

Aquatic invasive species are a global problem, and international collaborative research can speed the development of tools to prevent invasions and mitigate impacts when invasions occur. NIWA and SERC have common science objectives and concerns in the field of marine biosecurity. The use of common techniques in each country will enhance our ability to answer key questions related to invasion biology by increasing sample sizes and allowing comparisons among regions.

Alien species are a major threat to the ecological integrity of New Zealand’s coastlines. Over the past 100 years, foreign species have become established here at a rate of about one every 9 months. The chances of controlling or eradicating an outbreak of an exotic species are greatest if it is detected early, yet surveillance techniques for detecting and identifying marine pests while they are still in low numbers are rudimentary. Of the many non-indigenous species known to have established in New Zealand, 69% are fouling organisms that settle on surfaces such as rock walls, pilings, and ship hulls. ‘Passive surveillance’ techniques involving the deployment of specially designed settlement surfaces in areas considered to be high-risk points of entry can enhance our ability to detect organisms soon after they arrive in the country.

While at SERC, Isla participated in an intensive field and laboratory programme to retrieve and analyse almost 300 settlement plates deployed at docks and marinas in Chesapeake Bay. She investigated patterns of invasion by marine invertebrates, and explored the characteristics of habitats and species that influence the success of biological invasions. She received training in the appropriate techniques to estimate biomass, measure patterns of coverage, and identify marine organisms that are known pests in other parts of the world. In addition to the training received at SERC, Isla also attended and successfully completed a workshop on Marine Bioinvasions led by world expert Dr James T. Carlton at the Oregon Institute of Marine Biology.

Isla’s visit to the USA was funded by a NIWA Technical Training Award with a generous contribution of time and expertise from the Marine Invasions team at SERC.

Barb Hayden and Graeme Inglis [b.hayden@niwa.co.nz]