What is Biodiversity?
Biological diversity, or biodiversity, is the variety of all species on earth. It is the different plants, animals and micro-organisms, their genes, and the terrestrial, marine and freshwater ecosystems of which they are a part1.
For the last 200 years, Australia has witnessed the largest documented decline of biodiversity of any continent in the world1. The repercussions of this decline are not yet fully understood, however, it is feasible that the loss of key species such as bees could have a dramatic affect on our way of life. The goods and services we have come to rely on are inevitably derived from the wide variety of organisms on our planet. It is in our own best interests to preserve biodiversity.
North Sydney's Biodiversity
North Sydney Council is a small, highly urbanised local government area. Only 5% of the original vegetation observed before European settlement remains. It occurs in narrow fragmented reserves that are vulnerable to urban pressures. Council's Bushland Plan of Management addresses these issues and aims to build ecological resilience.
In 2007, Council engaged ecologists to survey avian biodiversity and to prioritise the habitat areas critical to the survival of less common native birds in our bushland reserves. Then in 2010, ecologists undertook a more comprehensive Natural Area Survey of all North Sydney's remnant bushland. Several threatened plant and animal species, and three endangered ecological communities were identified. This survey provided a benchmark of North Sydney's natural assets and a measure of their intrinsic value for rehabilitation and recovery.
1 (Aust Govt Dept of Sustainability, Environment, Water, Population and Communities)
Natural Area Survey Highlights
North Sydney's bushland reserves support 12 distinct native vegetation communities, three of which (Coastal Saltmarsh, Swamp Oak Forest on Coastal Floodplains, and the Sydney Turpentine-Ironbark Forest) are listed as endangered ecological communities in NSW.
One type of Turpentine-Ironbark Forest, called Red Gum Foreshore Forest is rare and unusual, and is listed as "critically endangered" under Commonwealth legislation.
Two biodiversity hotspots (threatened) were identified:
- The Wollstonecraft reserves at Berry Island, Bandangi, Gore Cove and Smoothey Park have the most native vegetation communities, with 10 out of the 12 communities found there.
- Tunks Park was identified as the most important reserve for small native birds.
Other findings were:
- 347 plant species were recorded, two of which are nationally threatened - the Sunshine Wattle (Acacia terminalis subspecies terminalis) and the Magenta Lilly Pilly (Syzgium paniculatum)
- 39 plant species are listed as significant at the Sydney Metropolitan Catchment Management Authority (SMCMA) regional level
- 190 native terrestrial vertebrate species were recorded in North Sydney, including 4 frog species, 20 reptile species, 148 bird species and 18 mammal species
- 114 of these species still occur consistently in the area
- 3 threatened animal species occur regularly in North Sydney - Powerful Owl (Nixon strenua), Grey headed Flying-fox (Pteropus poliocephalus) and the Eastern Bent-wing Bat (Miniopterus schreibersii)
- 15 species are listed as migratory species under Commonwealth legislation and international migratory species agreements
- 15 species are significant at a regional level
- 61 species are significant at a local level