Overview A research investigation was conducted at Marist Regional College concerning Shorewell Creek, a small stream which flows through the City of Burnie in North Western Tasmania. This waterway is known to support populations of the threatened Burnie Burrowing Crayfish (Engaeus yabbimunna), a species which was unknown until 1994 when a small colony was discovered in the Burnie City Park.  Most of the original vegetation has been removed from the catchment of Shorewell Creek with much of the area now given over to urban and agricultural land use purposes. This has severely restricted the habitat available to the Burnie Burrowing Crayfish in the Burnie area.  The project involved monitoring streamwater and mapping vegetation and burrow distributions in order to assess the quality of the remaining habitat and then to use this information to suggest various ways to ensure the survival and recovery of the Burnie Burrowing Crayfish on Shorewell Creek.  1.0 INTRODUCTION  Engaeus is a genus of freshwater crayfish found only in south-eastern Australia (Horwitz, 1990). Most members of Engaeus are characterised by their ability to contruct burrows. The animals spend most of their time in these burrows and are therefore rarely seen. Parents, together with several seasons offspring, may be found living in the same burrow (Horwitz & Richardson, 1986).  Three types of burrows have been recognised by Horwitz & Richardson (1986). Type 1 burrows are found in or directly connected to open water, Type 2 burrows are connected to the water table and Type 3 burrows are independent of the water table. Type 2 burrows may become flooded during periods of high rainfall during which time the adult crayfish may live on the surface, while the offspring disperse.  Thirty four species of Engaeus have now been recognised, of which 12 are found only in Tasmania (Horwitz, 1994).  Engaeus yabbimunna was unknown until 1992, when a population was located at Burnie on the North West Coast of Tasmania (Doran & Richards, 1996). For this reason E. yabbimunna was given the name "Burnie Burrowing Crayfish". E. yabbimunna is distinguished from similar species by slight morphological differences including the presence of only one row of tubercules ("bumps") on the chelae ("claws"), an upturned spine on the rostrum and the pattern of pores on the sternum (Horwitz, 1994).  Doran and Richards (1996) note that E. yabbimunna live in burrows which always reach the water table. This corresponds to Horwitz & Richardson's (1986) Type 2 burrows. The species is thought to feed on rotting vegetation and perhaps aquatic macroinvertebrates (Doran & Richards, 1996). At the time of its discovery in 1994, it was considered to have an extremely restricted distribution and was initially known from only three creeks in the Burnie area ((Doran & Richards, 1996). However, further work has revealed a wider distribution, with the species having been recently identified from several catchments west of Burnie (J. Nelson, A.M.M. Richardson, pers. comm.). Nevertheless, E. yabbimunna is considered to be a rare species whose survival is threatened by many pressures, including habitat removal and disturbance as well as decreased water quality (Doran & Richards, 1996).  Marist Regional College's Burnie Burrowing Crayfish Project consisted of a group of  Year 10 students who monitored water quality and mapped vegetation and the distribution of crayfish burrows along a creek flowing through the City of Burnie. The aim of the project was to assess the habitat available to E. yabbimunna in the area with a view to developing a recovery plan for the species.  1.1 The Study AREA The study area was located in the riparian zone of Shorewell Creek, a small stream rising on the southern outskirts of Burnie (see Fig. 1). This stream was chosen because the small catchment size (approximately 5 km2 ) and absence of major tributaries allowed a concentrated mapping program to be undertaken. The total length of the stream is around 5 km with the source located at series of seepages in an area of rolling topography overlying basalt bedrock. De Gryse & Hepper (1994) report that the original vegetation in the area consisted mainly of Eucalyptus spp. Acacia melanoxylon (Blackwood) and Melaleuca spp. (Tea Tree) with Dicksonia antarctic (Manfern) and other ferns in the understory. Today most of this original vegetation has been cleared for agricultural and urban land use purposes.  Click to Enlarge Fig, 1: Study Area, - Shorewell Creek, Burnie, Tasmania.  The headwaters of the stream have been dammed forming an on-farm water storage. The surrounding land is used for grazing cattle with stock having access to the stream banks. Approximately 0.4 km from this water storage the stream is piped underground for 200 m through the City of Burnie's Works Depot where it emerges adjacent to the works depot for an energy distribution company. From here the water flows through a public recreation reserve for 1 km before passing through farmland where, once again, stock have unrestricted access to the banks. After this the stream flows through a steep sided valley for about 0.5 km with urban land use on either side before entering a pipeline through a disused tip site. Having emerged from the disused tip the water flows through a highly modified section of stream which includes private gardens, a large duckpond and a plant nursery. At the northern end of the Burnie Park, the water flows over a small waterfall after which it runs through an artifical channel before discharging into Bass Strait.