Ecological island
An ecological island is a term used in New Zealand, and increasingly in Australia, to refer to an area of land (not necessarily an actual island) isolated by natural or artificial means from the surrounding land,[1] where a natural micro-habitat exists amidst a larger differing ecosystem. In New Zealand the term is used to refer to one of several types of nationally protected areas.
In artificial ecological islands (also known as mainland islands):
- all non-native species (at least predatorspecies) have been eradicated,
- native species are reintroduced and nurtured, and
- the natural or artificial border is maintained to prevent reintroduction of non-native species.
The ultimate goal is to recreate an ecological microcosm of the country as a whole as it was before human arrival. There is usually provision for controlled public access, and scientific study and research.
The definition does not include land within a fence erected to:
- protect farm animals from wild predators
- protect a specific species from specific predators
- exclude farm animals only
- exclude native animals (although some native animals, weka for example, may need to be excluded during a species' recovery phase).
Background
The concept of mainland islands was pioneered in
With human colonisation came many accidental or deliberate introductions of mammals and birds. These wrought havoc with native species and many became extinct, many others were reduced in range and number, with some teetering on extinction. Traditionally pacific rats (Rattus exulans), Norway rats (Rattus norveigucus), ship rats (Rattus rattus) cats, ferrets, stoats, and weasels were all considered to be the main culprits in the decline of native species of New Zealand birds, reptiles and insects. More recent information adds hedgehogs and mice to the list. These species have been introduced for a variety of reasons and some inadvertently. The effect remains the same: they have all contributed to the decline of native animals. Possums and deer did the same for the forest.
However, New Zealand also includes many offshore islands, some of which contained species rare or extinct on the mainland because introduced pests could not reach them.
Offshore islands
Increasingly over the last hundred years, New Zealand's
Fenced enclosures
Following the example of what had been achieved on offshore islands, groups of New Zealanders decided to create artificial ecological islands on the mainland so that the public could have easier access and learn what New Zealand looked and sounded like before human colonisation.[3] There are excellent projects where alien species numbers are kept down by various methods other than a pest-exclusion fence or the coastline, but these are not generally described as ecological islands.
Projects that do meet the criteria, or are aiming to, include:
- New Zealand
- 1999 Zealandia
- 2004 Tawharanui Open Sanctuary[4]
- 2005 Bushy Park[5]
- 2006 Maungatautari Restoration Project[6]
- 2007 Orokonui Ecosanctuary
- 2009 Glenfern Sanctuary Charitable Trust[7]
- 2011 Shakespear Regional Park
- 2016 Brook Waimārama Sanctuary
- Moehau Environment Group[8]
- Australia
References
- ISSN 1540-9309.
- ^ "Ecological restoration of offshore islands". www.doc.govt.nz. Retrieved 2021-01-29.
- ^ Innes, John; Lee, William G.; Burns, Bruce; Campbell-Hunt, Colin; Watts, Corinne; Phipps, Hilary; Stephens, Theo (2012-01-01). "Role of predator-proof fences in restoring New Zealand's biodiversity: a response to Scofield et al. (2011)". New Zealand Journal of Ecology. 36 (2): 232–238.
- ^ "Tawharanui Open Sanctuary Society". Tawharanui Open Sanctuary Society. Retrieved 2021-01-29.
- ^ "Bushy Park Tarapuruhi – Bushy Park Tarapuruhi Forest Sanctuary & Historic Homestead". Retrieved 2021-01-29.
- ^ "Sanctuary Mountain Maungatautari". MOCA. Retrieved 2021-01-29.
- ^ "Glenfern Sanctuary | About Us". Glenfern2019. Retrieved 2021-01-29.
- ^ "Vandals hit conservation fence on Coromandel". NZ Herald. Retrieved 2021-01-29.
- ^ University, La Trobe. "Nangak Tamboree Wildlife Sanctuary". www.latrobe.edu.au. Retrieved 2021-01-29.