City of Sydney Council has recently created two ‘habitat trees’ in Sydney Park. Both trees are Eucalypts & are located close to the lower pond. They are surrounded by other tall trees & so would make attractive homes for wildlife.
A significant difference from the ‘habitat tree’ created by Marrickville Council in McNeilly Park is that the branches have not been ring-barked – at least it had not been done when I saw these trees. It appears that Sydney Council has created more holes in each tree than the one in McNeilly Park.
Like Marrickville Council, the City of Sydney Council is also using these trees as a demonstration for professionals on to how to create nesting hollows for birds & animals.
I really like this movement to retain trees that would have been removed previously. The idea is to mimic dead trees found in the bush.
The more I read about dead trees the more I realize how important these old dead trees are to the ecology of the environment. Standing dead trees in the bush are called snags & stag trees.
Only old trees have hollows & these trees often need to be 100-150 years old before they start creating hollows. Eucalypts start creating hollows after dropping branches & we know that once branch-dropping starts, the tree is removed for the safety of the human population.
“Australia-wide, 15% of all land birds use hollows. These 114 species include parrots, owls cockatoos & lorikeets, ducks, treecreepers, owls, owlet-nightjar, kingfishers, pardolotes, martins & woodswallows.” ~ Sourced from Wildlife Notes, Department of Conservation & Management April 2005.
“One of the least known characteristics of Australian animals is their high utilisation of tree hollows. For example, the proportion of Australian animals that use tree hollows is three times greater than in North America & twice as great as in South Africa.
About 350 Australian animals use hollows for either roosting or nesting. This includes:
- half of our small bats,
- nearly 90% of our parrots,
- all of our gliders,
- all but one of our owls
- all of our tree-creepers.
Nearly 20% of our birds use hollows in some way. For 60% of these, hollows are essential.” http://www.ozbox.net.au/anim&holl.htm
Of the 22 species of bats that have been recorded to utilise tree hollows in NSW, 10 of these are listed as threatened. (Gibbons & Lindenmayer 1997).
Repurposing trees that would have been removed so that they become useful for wildlife is a great idea. Tree hollows in urban environments are very rare. I look at trees all the time, but only know of three trees on public land in Marrickville LGA that have natural hollows. I applaud this move to help wildlife & improve on biodiversity by both Councils. It will be interesting to see what wildlife do take up residence in these hollows.