4.0 CONCLUSIONS AND RECOMMENDATIONS 4.1 Vegetation Perhaps the most significant finding of this study is the fact that Engaeus spp will occupy quite degraded habitats, provided Manferns are also present in the same area. It was not possible to determine from this study whether this is linked to the fact that Engaeus spp. utilise Manferns as a food source is preferred by (Doran & Richards, 1996), or whether it is because Manferns grow in the type of habitat as that which Engaeus spp. However, given the threat a disjunct population distribution poses to the continuing survival of E. yabbimunna, consideration should be given to the establishment of continuous areas of native vegetation along Shorewell Creek. Although some revegetation work has already been undertaken by the Burnie City Council at Sites B6 and B7, there is clearly a need for further plantings along Shorewell Creek. 4.2 Water Quality The quality of the water in Shorewell Creek is of some concern. Although it may be argued that the water in burrows of E. yabbimunna is derived mainly from groundwater, streamwater was observed to flood burrows following periods of high rainfall. Also, because E. yabbimunna may utilise macroinvertebrates as part of their diet, any changes in the macroinvertebrate community structure of the stream as a result of declining water quality may have adverse impacts on the species. Hogg & Norris (1991) have shown that increased turbidity in a stream will result in the loss of both the number and types of macroinvertebrate species and for this reason steps should be taken to control water turbidity in Shorewell Creek. This may involve fencing to exclude stock from stream banks. Revegetating the riparian zone may also assist this problem and at the same time will help to decrease water temperatures in the stream (Lake & Marchant, 1990). The effect of dams on streams has been documented by Lake and Marchant (1990) and include a decrease in the diversity of macroinvertebrates at downstream sites as well as increased stream sedimentation. Therefore, to protect aquatic habitats, no further dam construction should be permitted on Shorewell Creek. The threats to aquatic ecosystems from stormwater runoff include debris, animal droppings, detergents and other pollutants, oil and rubber from roadways (White, 1997), as well as warm water and sediment from roads and other surfaces. Communities are generally unaware of the fate of urban stormwater and for this reason an education campaign suggesting ways in which its impacts could be minimised should be undertaken. This might be as simple as encouraging people not to wash their cars on the street or to bury their pet's droppings. The probabilty that water is leaching from the old refuse site is a cause for concern. Although crayfish burrows have been located immediately downstream from this site, the water quality here is undoubtedly poor and in the interests of the stream ecosystem, local authorities should feel some obligation to alleviate its effects. Consideration could be given to the establishment of a wetlands area to filter tip runoff. The duck pond adjacent to Site B6 needs close considereation Apart from having an adverse effect on water quality, ducks take macroinvertebrates as part of their diet, and their continuing presence close to a site which Doran & Richards (1996) have classified as "major location" of E. yabbimunna must be questioned. 4.3 Community Education It became obvious during our research that few people in the Burnie area are aware of the existence, let alone the threatened status of E. yabbimunna. It would therefore be worthwhile as an extension to this work, for our group to undertake a community awareness campaign publicising the species and the threats to its existence. This might take the form of talks to community groups such as senior citizens and garden clubs, as well as local schools. The production of a brochure might also be used to spread the message to the wider community. The support of community groups such as Landcare to assist in rubbish and weed removal from the creek and surrounding area could also be canvassed. In conclusion, it can be seen from this study that Shorewell Creek is quite a degraded waterway. Nevertheless, it supports a number of populations of the endangered "Burnie Burrowing Crayfish". It is becoming increasingly recognised that, ethically, all species have the right to exist (State of the Environment Advisory Council, 1996) and for this reason the Burnie community has a responsibility towards preserving the habitat of E. yabbimunna. Lake and Marchant (1990) write that the first step towards rehabilitating a waterway should be a survey of the stream and its catchment. This study by Marist Regional College students can therefore be considered to be the first step in the rehabilitation of Shorewell Creek.