Lectures and Green Developments

After a weekend packed with activities, everyone enjoyed the opportunity to sleep in thanks to the free morning. Our day started off in the afternoon with several lectures from Dr. Dean Anderson and Dr. Will Allen at Landcare Research in Lincoln.  Dr. Anderson’s lecture focused on mammal pests in New Zealand and the many issues surrounding the management and control of the invasive species that threaten native biodiversity.

The unique fauna of New Zealand evolved in the absence of mammals for 65 million years and as a result, the arrival of people and subsequent introduction of small predatory mammals have severely impacted the native flora and fauna.  Habitat loss and introduced species have led to the extinction of 40% of native land birds and the listing of over 600 taxa as under threat of extinction.

The mammalian pests in New Zealand create a “conservation paradox” in which animals need to be killed in order to actually accomplish conservation.  For many endemic species of birds, introduced predators like brush tail possums, stoats and hedgehogs pose a serious threat to eggs and fledglings.  Studies have shown that increased exotic species population control measures are correlated with increased native vegetation growth and increased native species reproduction.  Because eradicating invasive species is so expensive, continued assessment to evaluate program efficiency and ongoing research to develop more effective methods and policies are vital to the overall mission of protecting the biological heritage of New Zealand.

As a fun fact, we also learned that our fearless leader is related to several native species thanks to his ancestor, Ferdinand von Hochstetter, whose geological survey work in New Zealand led to a few species with his namesake.  The flightless Takahe (Porphyrio hochstetteri), carnivorous Amber snail (Powelliphanta hochstetteri) and Hochstetter’s frog (Leiopelma hochstetteri) all share a common root with Dr. Hostetler!

Our next lecture from Dr. Will Allen was on managing program performance. We learned about the importance of managing for specific outcomes, particularly for initiatives geared toward improving sustainability and biodiversity. 

The class split into small groups to create examples of using logic models to achieve specific outcomes.

After the lectures, we took a quick afternoon tea break at coffee culture before our last stop of the day, which was a nearby green development community in Lincoln.  A local subdivision designed with sustainability in mind featured permeable pavement and swales to a retention pond surrounded by native vegetation like hebe, New Zealand flax, lacebark, and toitoi.  This system of drainage allows rainfall to percolate without harming the environment by keeping heavy metals and other particulates out of the groundwater. 

The protected Liffey Stream was also surrounded by native vegetation and provided homes for several species of birds.  We also learned the importance of eco-sourcing, where replanted native vegetation is sourced from nearby locations in order to maintain natural plant distributions and genetic diversity.  At this location, we learned that the undisturbed New Zealand flax was an indicator that the plants were likely sourced from the North Island since insects were not using it as a food source.

Our day ended with a quick drive through the neighboring Ngai Tahu development, which is a Maori development company.  This part of the development also had rain gardens, which are another method of collecting and filtering rainfall, complete with native Kowhai trees and New Zealand flax.  Both communities shared the green development aspects of native vegetation in shared spaces with efforts to improve water quality, more energy efficient homes with insulation and heat pumps (instead of pollution emitting wood stoves), and informative signage.

-Mimi