Blog on Forest Health

By Liz Manning (Executive Officer, Wandoo Recovery Group).

Recently I spent two mornings helping Tracey Moore, (PhD candidate, Murdoch University) monitor her fauna traps in parts of Wandoo National Park.  Tracey is studying how changes in the overstorey canopy, predominantly wandoo (Euc. wandoo), is related to the abundance and diversity of small fauna.  Part of Tracey’s field work involves monthly trapping sessions in the Dryandra Nature Reserve and the Wandoo National Park.  This involves early morning starts!

Before the temperature rises, we check all traps to identify and release the animals. This time, we find a number of small humming frogs, a Gunther’s toadlet, a Gilbert’s Dunnart, a skink and a gecko. Tracey says that this result is in sharp contrast with the huge spread of fauna in Dryandra, where she found frogs, pygmy possums, mardos, dunnarts, dragons, skinks, geckos, bobtails, varanids, snakes and blind snakes.  We debate whether the recent bout of cool weather may account for the low diversity of fauna caught in this trap session. Or could it be something else?

The wandoo forest at sunrise is really beautiful; peaceful, yet alive with bird calls and the spring flush of flowering understorey plants. There are vivid splashes of colour from flowering understorey shrubs such as acacia, smoke bush, bottlebrush, poison bushes as well as a mass of ground cover species. Wandoo country affords such generous habitat for the great diversity of plants and animals that live within it. The leafy canopies of mature trees offer filtered shade and are full of birds and insects.  Hollows which form in large trees like wandoo and jarrah provide essential shelter, nesting and protection for many birds, bats, reptiles and mammals. Hollow logs on the ground house echidna, lizards, chuditch, numbats and young rufous treecreepers. Spring is the breeding season and many adult fauna divide their time between foraging for food and returning to their nests to feed and care for their young. I really love to see this.

While helping Tracey, I observe the wandoo trees exhibit varying states of crown health. Most trees have the classic stag head appearance, evidence that a widespread decline event occurred sometime previously (possibly around ten years ago). Scattered amongst these are healthy trees, with vigorous spreading crowns, heavy with buds.  The decline phase appears to have stabilised with trees showing signs of recovery, evidenced by the strong growth of epicormic shoots.

As we drive along the rough tracks, we come upon a huge jarrah tree, its base almost completely burnt out from a previous fire, yet the crown still very much alive. I take a photo of Tracey standing inside the enormous bole.  I also photograph a majestic wandoo near my home in Talbot Brook. I plan to nominate these trees on the National Register of Big Trees, www.nationalregisterofbigtrees.com.au