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scribbly bark moth...

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Question 2: A testable hypothesis I hypothesise that the bark of stressed smooth-barked eucalypts is more likely to host scribbly gum moth (Ogmograptis) larvae than the bark of healthy individuals. Question 3: Objective of the proposed research Scribbly gum moths are a common species in the Australian Capital Territory, New South Wales and Queensland, with various species of eucalypts called ‘scribbly gums’ due to the markings of larval trails (Cooke and Edwards, 2007). These eucalypt species are located in overlapping temperate and grassland areas (Centre for Australian National Biodiversity Research, n.d.). As abiotic environmental factors are the most important generalisable variables affecting the stress levels of plants (Maywald and Sutherst, 1989), it is possible that scribbly gum reactions to stress impact the distribution and abundance of scribbly gum moths. There are eleven subspecies of Ogmograptis, but as the differences are subtle the study would focus on the species as a whole (Horak et al., 2012). The objective is therefore to understand whether there is a link between stress levels and scribble abundance. Question 4: Conduction of the experiment The data collected would focus on trees with visible markings/scribbles, as we do not know enough about Ogmograptis to determine what variables may be at play for a tree to be completely unaffected (Cooke and Edwards, 2007). As the major factors impacting plant stress are temperature and soil moisture (Sutherst, 1999), data would be collected on annual temperature and rainfall and the individual stress of scribbly gums in response to these variables. This would be a natural experiment based on observational data as a controlled experiment with separate control and treatment groups would be highly impractical. Climate data are accessible from the Bureau of Meteorology, and the impacts of these variables can be observed on individual trees (Maiti et al., 2016). Many areas throughout the Australian Capital Territory would be suitable sites due to the high prevalence of scribbly gums such as Eucalyptus racemosa spp. rossii. Question 5: Potential results A bar graph of the abundance of Ogmograptis markings on the Y-axis and stress of eucalypts on the X-axis could demonstrate whether there is a link between the number and size of scribbles and the stress of the host (Figure 1). A positive relation would be seen if the hypothesis is accepted; as stress increases so would scribble rates. If there is a negative relation or no real correlation, the data would refute my hypothesis. The health of trees would be separated into categories, e.g. 1 for minimal stress levels and 5 for extreme stress. A similar scale could be used for abundance of Ogmograptis trails. Question 6: How this research could contribute to solving an ecological problem Very little is known about the biological functions and processes of the Ogmograptis genus, so this project could help understand its potential distribution and whether intermediate ecosystem disturbance aids in the propagation of larvae on stressed trees. Ogmograptis moths and scribbly gums may show commensalism (F. David Hockings, 2014), but as of yet this lacks scientific evidence. Larger ecological problems are currently impossible to address without this basic knowledge of species interactions, and this project could be a basis for understanding whether scribbly gums and their moths show commensalism or a form of parasitism with minimal damage to the host (Cooke and Edwards, 2007).

Question 1: Ecological interactions Is there a relation between the abundance of kangaroos versus rabbits in the Pinnacle Nature Reserve due to potential competition? Alternatively, is kangaroo abundance linked to annual climatic changes in rainfall or temperature patterns, which then affect food supply of grass? Is there a relation between the health of smooth-barked eucalypts and the abundance of scribbles left by scribbly gum moth larvae? Do birds display commensalism with trees, i.e. do they significantly aid in propagation of seedlings or add nutrients to the soil through droppings? Is sapling abundance higher in open areas where there is less competition for light and nutrients?

References: Centre for Australian National Biodiversity Research, n.d. Eucalyptus racemosa subsp. rossii [WWW Document]. EUCLID. URL https://apps.lucidcentral.org/euclid/text/entities/eucalyptus_racemosa_subsp._ros sii.htm Cooke, J., Edwards, T., 2007. 'The behaviour of scribbly gum moth larvae Ogmograptis sp. Meyrick (Lepidoptera: Bucculatricidae) in the Australian Capital Territory.' Australian Journal of Entomology 46, 269–275. https://doi.org/10.1111/j.14406055.2007.00606.x F. David Hockings, 2014. Pests, Diseases and Beneficials: Friends and Foes of Australian Gardens. CSIRO Publishing, 150 Oxford Street, Collingwood Victoria. Horak, M., Day, M.F., Barlow, C., Edwards, E.D., Su, Y.N., Cameron, S.L., 2012. 'Systematics and biology of the iconic Australian scribbly gum moths Ogmograptis Meyrick (Lepidoptera: Bucculatricidae) and their unique insect–plant interaction.' Invertebrate Systematics 26, 357–398. https://doi.org/10.1071/IS12022 Maiti, R., González Rodríguez, H., Sergeevna Ivanova, N., 2016. Heat stress tolerance of trees, in: Autoecology and Ecophysiology of Woody Shrubs and Trees. John Wiley & Sons, Ltd, pp. 266–269. https://doi.org/10.1002/9781119104452.ch22 Maywald, G.F., Sutherst, R.W., 1989. 'CLIMEX: recent developments in a computer program for comparing climates in ecology' [WWW Document]. Proceedings from the Simulation Society of Australia Inc. Eighth Biennial Conference. URL http://www.ciesin.columbia.edu/docs/001-374/001-374.html Sutherst, R.W., 1999. 'Climex: Climate Matching Made Easy.' CSIRO Publishing....