Flood Plain Lower Ringarooma River Ramsar site Ecological Character Description March 2012 Blank page Citation
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1.3Land Use and TenureThe land tenure of the site is complex. Within the site, approximately 60 percent of the area is owned by Rushy Pastoral (Figure 3), with the remainder being Crown land reserved under the Nature Conservation Act 2002. The Crown land includes the area between the Ringarooma River and the western boundary which is reserved as part of the Cameron Regional Reserve and the coastal and estuarine zone at the northern end of the site which is reserved as part of the Boobyalla Conservation Area (Figure 3 and Table 2). The boundary of the Ramsar site is displayed with a red line in Figure 3, The land owned by Rushy Pastoral (with the property name ‘Rushy Lagoon’ on Figure 3) extends well beyond the Ramsar site boundary, covering a total of 20 758 hectares. Table 2: Land tenure and area of parcels within the Flood Plain Lower Ringarooma River Ramsar Site
*Areas in Table 2 do not add up to total site area, as there is no cadastral information (and hence no area data) for the foreshore and estuary of the site (see Figure 4). Areas rounded to whole hectares. Figure 4 displays in more detail the land tenure within the site. Crown land areas are shown with red hatch overlay, the privately-owned land has yellow diagonal lines as overlay and the boundary of the Ramsar site is shown as a thick red line. There is no cadastral information (and hence no area data) for the foreshore and estuary of the site, and these areas have no overlay in Figure 4. The site accommodates livestock grazing on the Crown leasehold land and the private land. Much of the land surrounding the site has been cleared for agriculture. The surrounding areas of the site are prone to siltation which has been primarily caused by erosion from mining areas. Within the site, one or more dams have been proposed (Dominique Couzens, personal communication) potentially impacting the input of freshwater tributaries to the wetland system. New dam developments near the wetland would require a referral under the EPBC Act and would require assessment of the potential impacts under this Act. Water extraction rights have also been allocated upriver, including some for hydroelectric purposes. Potential impacts of these on the hydrology are discussed in a later section (Section 3.2.5). 
Figure 3: Private land ownership in the Flood Plain Lower Ringarooma Ramsar Site (Supplied by NRM North). 
Figure 4: Land tenure of the Flood Plain Lower Ringarooma River Ramsar Site (Supplied by NRM North). 
Figure 5: Leasehold land within Flood Plain Lower Ringarooma River Ramsar Site. Pink hatching indicates the leasehold land. (Map courtesy of Emma McDowell of Tasmanian Parks & Wildlife Service, from The List. Quality of the image is poor due to it being sourced as a screen image of the online database, the only source of the information) Ecological Character of the Flood Plain Lower Ringarooma River Ramsar SiteThis chapter describes the components, processes and benefits and services of the site and the linkages between them. Subsequent to these descriptions, the components, processes and benefits and services that are critical to the site’s character are identified, followed by presentation of conceptual models of the site. 1.4Ecological Zones of the SiteThe site can be separated into three zones – a coastal zone, an estuary zone and a freshwater zone (Figure 6). This section of the ECD briefly describes the coastal zone, followed by the estuary and freshwater zones. 
Figure 6: The three ecological zones of the Flood Plain Lower Ringarooma Flood Plain Ramsar Site. 1.4.1The Coastal ZoneThe coastal zone covers the entire coast of the site (three to four kilometres), including the combined mouth of the Boobyalla and Ringarooma Rivers and hence part of the estuary zone described in the following section. The coastal zone contains the foredunes and sandy beach of the site, as well as the delta (Figure 7). 
Figure 7: Coastal Zone of the Flood Plain Lower Ringarooma River Ramsar Site (May 2007, L.N. Lloyd). The coast of north-east Tasmania is largely formed of, or underlain by, extensive folded and metamorphosed sandstones and slates deposited during the Ordovician and Silurian periods (DTAE 2007). Granite rocks of Devonian age are prominant in the catchment. This is the source of the tin which has been mined in weathered deposits. Since the middle Tertiary (approximately 36 million years ago) and especially during the last two million years, the geomorphology of the site has been dominated by alternating glacial and interglacial phases, with glacial phases characterised by colder, drier conditions and lower sea levels than the interglacials. During glacial periods, Bass Strait was a broad sandy plain and it is thought that sands blown from Bass Strait during glacial phases provided source material for the extensive sandy shores and coastal dune complexes along the north-east coast of Tasmania (DTAE 2007). The site contains good examples of parallel dunes (dunes located behind the foredunes) and also large transgressive dune fields, which migrate across the landscape reworking sediments and inundating pre-existing landform features (DTAE 2007). Other bedforms within transgressive dune fields can include parabolic dunes, blowouts, lagoons, swales and deflation basins that demonstrate a range of process-response feedbacks in the system. The range in bedform adds diversity to the geomorphic components of the dune field (DTAE 2007). The transgressive dune fields at the site are listed on the Tasmanian Geodiversity Database as part of the Northeast Tasmania Pleistocene Aeolian Systems and include Bowlers Lagoon. The estuary of the site contains a flood tide delta (see section 3.1.2), which is expected to be dominated by sediment of marine origin, or at least reworked by marine processes (Bradbury, personal communication). The Ramsar wetland types (Figure 10) that occur within the coastal zone are: sandy shores (wetland type E); delta (wetland type F); and intertidal mud and sand flats (wetland type G). A number of beach nesting shorebirds have been recorded breeding on the beaches of the site, comprising the little tern, hooded plover, fairy tern, pied oystercatcher and red-capped plover (Eric Woehler, Birds Tasmania, unpublished data). Within the site, part of the beach is a known site for nesting by little terns and fairy terns. Although the total numbers of nesting terns within the site are small, the relatively low disturbance of the site makes breeding success far more likely at the site than elsewhere in Tasmania with more nests but greater disturbance; that is, one pair of small terns nesting at the site is more likely to succeed in breeding than other small colonies around the state (Eric Woehler, Birds Tasmania, personal communication). Although information on these species is limited, some general information on habitat and diet for each species is provided in Table 3, below. The information provided in Table 3 has been collated from Birdlife International (2009), DEWHA (2010b), Birds Australia (2010) and Pizzey (1980). Table 3: Nesting shorebird species of the Ringarooma coastal zone, with their common habitat and diet (Pizzey 1980; Birdlife International 2009; Birds Australia 2010; DEWHA 2010b).
1.4.2The Estuary ZoneThe estuary zone is wave dominated, with a flood tide delta (Jason Bradbury, personal communication). Physical features present at Ringarooma Estuary that are considered typical of flood tide deltas include a shorefront barrier, a flood/ebb delta, an area of salt marsh, tidal sand banks and the channel. There also appears to be the beginning of a central basin (coastal lagoon) behind the shorefront barrier (Figure 7). These estuaries often have abundant intertidal habitats including salt marshes, salt flats, and melaleucas (Heap et al. 2004). The high-energy channels in river dominated estuaries allow increased flushing of sediment, water and nutrients into the sea (Figure 8). 
Figure 8: Estuary Zone of the Flood Plain Lower Ringarooma River Ramsar Site (May 2007, L.N. Lloyd). Wave dominated estuaries are considered ‘mature’ in terms of evolution and tend to be morphologically stable (assuming stable sea levels). They often have a narrow entrance which can restrict marine flushing, although this is counter-balanced by high river flows that expel marine water and flush material from the delta. The short residence time for deposited material results in little processing or trapping of associated nutrients and contaminants (Coastal Zone Australia Ltd 2005). Typical of flood tide deltas, the Ringarooma estuary has a direct connection between river and sea, via a channel flanked by a low-lying vegetated Flood Plain. The channel is kept open by the relatively high river velocities and a dune barrier partially constricts the estuary entrance, preventing it from expanding into a large, open estuary. The ‘mature’ nature of flood tide deltas means that they have been mostly filled by sediments. In the case of the Ringarooma estuary, this ‘maturation’ has probably been created prematurely through an increased rate of sediment yield from the catchment as a result of tin mining (discussed in Section 2.1). The Ramsar wetland types that occur within the estuary zone (Figure 10, Table 4) include estuarine waters (permanent water of estuaries and estuarine systems of deltas wetland type F); intertidal mud, sand or salt flats (wetland type G); intertidal marshes (includes salt marshes, salt meadows, saltings, raised salt marshes[tidal brackish and freshwater marshes] wetland type H); and coastal brackish/saline lagoons (brackish to saline lagoons with at least one relatively narrow connection to the sea; wetland type J). Saltmarsh has been noted as being present in the estuary section of the site (RIS 2005; personal observations) but without assessment its extent, composition or condition is not known. Similarly, species of fish in the region that inhabit coastal streams or migrate between freshwater and the sea have been identified, but no data have been found on their distribution or abundance. Macroinvertebrate data were also unable to be found for the estuary at the time of listing, although some information in Edgar et al. (1999) suggests the estuary supports an average number of macroinvertebrate species for this estuary-type within Tasmania. Bird surveys were undertaken in the southern section of the Ramsar site as part of the Musselroe wind farm studies (Organ et al. 2003) and in November 2000 DPIW personnel recorded shorebirds at the mouth of the Ringarooma River and Boobyalla Rivers, including hooded plover, red-capped plover, greenshank, red-necked stint, ruddy turnstone, curlew sandpiper, black-fronted dotterel and fairy tern (Sally Bryant, DPIW, personal communication). These records contribute useful information on the site; however, systematic surveying of the estuary area would contribute important data for the understanding of the estuary avifauna. Similar to other components contributing to the ecological character of the estuary, there is little information available on the water quality of the estuary. Given the location of Ringarooma Bay, any impacts on water quality in the estuary would originate from the freshwater input rather than the marine. Despite this reported contamination, the estuary supports an invertebrate fauna of average diversity, significant fish populations, and a diverse bird fauna including the species listed above. 1.4.3The Freshwater ZoneThe freshwater wetlands of the site are formed on a Flood Plain that widens downstream of a shallow and constricted valley (Jerie and Household 2001). In the wider and flatter area of the lowland Flood Plain, water from high flow events can leave the channel and spread out, filling in depressions in the landscape. As the water leaves the channel during high flows it quickly loses velocity and deposits the heavier sediment along the channel edge, forming natural levees. These natural levees impede the water from subsequently returning to the channel, leaving it to form a mosaic of seasonally-inundated and permanent water bodies (Figure 9).  
Figure 9: Freshwater Zone of the Flood Plain Lower Ringarooma River Ramsar Site (Mosaic of Photos, May 2007, L.N. Lloyd). The freshwater wetland complex is surface water dominated. Local groundwater appears to be controlled by river flows and overflows, with the surface water generally recharging the local groundwater. The site’s hydrology is therefore dependent on the Ringarooma River and several small tributaries to the site. The wetlands are generally shallow and clear, providing optimal conditions for submerged and emergent macrophyte vegetation. The extent and period of inundation varies substantially across the site’s wetlands with corresponding variations in abundances and distributions of plant species. The water quality data from the Ringarooma River suggests that the wetlands’ water is of high quality for aquatic ecosystems, with low nutrients, low salinities and pH readings approximating neutral (that is, pH of 7). The wetland complex contains a shallow mosaic of temporary and permanent wetlands with low nutrients, clear-water, circum-neutral pH and low salinities. The vegetation is largely emergent and submerged leaf macrophytes within the areas of standing water, grading through sedgeland and heathland to treed swamp forests. The diversity of fauna at the site is dependent on the diversity of habitat afforded by the geomorphic, wetland and vegetation mosaic. The Ramsar wetland types that occur within the freshwater zone include: seasonal waterways (wetland type N); permanent freshwater marshes, pools and ponds (below 8 hectares), with emergent vegetation (wetland type Tp); seasonal freshwater marshes and pools, including seasonally flooded meadows and sedge marshes (wetland type Ts); shrub-dominated wetlands (wetland type W); and freshwater, tree-dominated wetlands (freshwater swamp forest) (wetland type Xf). Within this system, the geomorphology of the site is a primary driver of the other components of ecological character. The landforms have a profound influence on the distribution of flows and the expression of groundwater influences. Further, the landforms – through the control of spatial and temporal extent of inundation – also have a profound influence on the distribution of vegetation communities and their dependent fauna and allied flora. Currently, water quality data is limited to the Ringarooma River at Gladstone, which indicates that the water entering the wetland system from the River is high quality. However, water also enters the Ringarooma River and wetlands from tributaries downstream of Gladstone and the impacts of land uses (including the re-opened Scotia mine and increasingly intensive dairying) on the water quality needs assessing. Water quality needs to be maintained, particularly for fish and macroinvertebrate species that live in the water column, but also for the aesthetics of the site and the water fowl that rely on the system as breeding and feeding habitat. 
Figure 10: Ramsar wetland types of the site (at time of Listing; Source NRM North). Table 4: Ramsar wetland types identified for the site at time of listing and their areas (in hectares).
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