In earlier posts we showed the massive impact that Fireblight Beetles have on the regrowth of some Wattle species following the 2009 fires. This included a massive dieback of Wattles which was most visible in spring followed by a recovery in Summer when the Beetles stopped being active. Well the cycle of dieback has started again and currently the Beetle Larvae are actively chomping away on the new Wattle growth. See this video below for vision of the Larvae in action and let this site know if you can find any activity in a forest near you. This video was taken in the Won Wron State Forest.
In the Spring time last year this site posted an article on the damage to Wattles that Fireblight Beetle can cause, where thick regrowth of Black Wattle had been completely defoliated by these beetles and their larvae.
Over Summer the Fireblight Beetles have gone to ground and the Wattles have staged a dramatic comeback, with virtually all the wattles that looked dead and gone re-sprouting with fresh new growth along with new seeds germinating. Surely there will be another dramatic change later in the year in the cooler months when the Beetles become active and the Black Wattles will cop another attack. The whole process of the Wattles losing their foliage in spring would benefit other native plants that are fighting for space and light.
Recently a fairly dramatic change to the understorey has been occurring in some areas affected by the 2009 Bushfires. In some localities where the fires triggered mass germination of either Black Wattle (Acacia mearnsii) or Silver Wattle (Acacia dealbata) widespread defoliation and dieback of these species has become very apparent.
The cause of this dieback is an insect known as the Fireblight Beetle (Peltoschema orphana ). The Beetles lay eggs on the underside of the leaves and the small grub like larvae also feed on the foliage. The species (although native to Australia) has been identified as a significant pest when people have tried to establish Wattle plantations and the thick regrowth after fires of the wattles has mimicked these conditions.
The dieback has resulted in a rapid opening up of the understorey and more light and less competition will enable other species to grow. Look out for weeds taking advantage of this new open space, but hopefully the event can provide an opportunity for other native understorey species to flourish, while retaining enough Black and Silver Wattle trees to continue to provide important habitat for animals such as sugar gliders and various bird species.
The Beetle is thought to avoid summer heat by hibernating in spring. It emerges in Autumn to start eating new foliage and lay its eggs. The hatched larvae then form into new beetles and the cycle continues.
The Eastern Grey Kangaroo is one species that has recovered quickly after the fires. With their ability to move quickly they had more chance of escaping the fire front and are also able to recolonise areas quickly. The open canopy after the fire provided the opportunity for fresh green grasses and herbs to grow which is the Kangaroos preferred diet.
Do you have some bushland on your property and are curious to know what wildlife might be around? As part of this Bushfire Recovery Project we are using remote cameras to get an idea of what animals have survived or recolonised the burnt areas. At this stage (after about a month of filming) we have recorded species such as Eastern Grey Kangaroos, Swamp Wallabies and Wombats as well as Foxes (unfortunately widespread) and Rabbits. We are very keen to move our cameras around and hopefully get some evidence of some smaller marsupials thriving such as Bandicoots and Bush Rats, or even get some snaps of a Strzelecki Koala. Get in contact with us at email@example.com if you are interested in borrowing a camera to use in your patch of bush.
A great way for anyone to monitor change in vegetation is to set up photo points. They are an easy way to identify changes that happen over time. They are especially useful for monitoring re-vegetation sites, weed invasions and after fires.The main thing you need is a camera and some basic equipment to set things up. Think carefully about what you want to photograph and what changes you might be looking for. It is a good idea to have a reference point in the photo such as a distinctive tree, post or sign. When you have decided on your sites it is a good idea to put a marker post such as a star-picket in the spot where you take the photo from. If there is room you can also put another post 5m to act as a sighting post so you know where to aim the camera each time. A GPS can be used to get the site co-ordinates in case you post gets moved.
When taking the shot take a note of how far the camera is zoomed in or out so you can repeat that setting next time. It is a good idea to try to photograph a view that is as close to normal as possible. If you use a wide-angle lens object at the edges will be distorted in size. Using a tripod helps to keep the camera at a consistent height. A great way of making sure you shots are consistent is to have a copy of previous photos of that site with you to help you frame the shot. It is best to take the follow-up photos at regular intervals depending on what your aim is it may be you want to take them once a month, once every six months or even just once a year. Below are some examples of photopoints taken at Tarra Bulga National Park.