Flood Plain Lower Ringarooma River Ramsar site Ecological Character Description March 2012 Blank page Citation
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1.2Ramsar Listing2.2.1 Original Listing Criteria The site was originally listed in November 1982 and is currently listed against the following criteria:
At the time of its original listing, the site was the subject of a RIS, a requirement of the Ramsar listing process. Since that time, the RIS has been updated in 1988, twice in 2003 and again in 2005. The updates have provided substantial increases in site information, including the justifications for listing under the specified criteria. Criterion one: A wetland should be considered internationally important if it contains a representative, rare, or unique example of a natural or near-natural wetland type found within the appropriate biogeographic region. The Flood Plain Lower Ringarooma River Ramsar Site is rare within the bioregion (Tasmania Drainage Division, Commonwealth of Australia 2010; Bass Strait IMCRA Province, Commonwealth of Australia, 2006), as it is rare for large rivers in Tasmania to be flowing through Flood Plains and forming the mosaic of wetlands that the Ringarooma River does (Stewart Blackhall, personal communication). The site contains good condition, regionally representative examples of wetland systems within a Flood Plain, with a mosaic of permanent and seasonal marshlands and a large river estuary (Boobyalla Inlet). Boobyalla Inlet is recognised as a Tasmanian estuary with high conservation significance (Edgar et al. 1999). Wetland vegetation communities recognised as threatened under Tasmanian legislation (DPIW 2007) and the site contains various wetland types which support these communities (DPIW 2006). These include Ramsar wetland type:
A section of the marshes known as The Chimneys is thought to be a remnant of a once more extensive lake system, older than other lakes in the area (being situated well within known Pleistocene dunefields) and potentially containing palynological and palaeobotanical fossils and megafaunal remains (Blackhall et al 2000, DEWHA 2010a). Criterion two: A wetland should be considered internationally important if it supports vulnerable, endangered, or critically endangered species or threatened ecological communities. This criterion is focused on species and communities listed at the Commonwealth level, principally through the EPBC Act or through international agreements, such as JAMBA, CAMBA, ROKAMBA and CMS Convention, discussed in Section 1. The site supports six fauna species listed on the IUCN redlist or as nationally threatened under the EPBC Act, including four wetland-dependent species:
The green and gold frog has declined dramatically across its range. Population studies have shown that green and gold frog populations are positively influenced by permanent water, the extent of aquatic vegetation, extensive riparian or Flood Plain grasslands and the presence of other nearby green and gold frog populations (Heard et. al. 2004). In Tasmania, the species occurred broadly across the north and east of the island and on Bass Strait Islands, although there is a report that in the Launceston area the number of individuals has shifted from abundant to scarce and that the species range has contracted in north-west, central and south Tasmania (DEWHA 2010b). The species is dependent upon permanent, still or slow flowing freshwater for breeding. The ideal breeding habitat is the shallow part of still or slow-flowing lagoons, generally with a complex vegetation structure (DEWHA 2010b). The combined habitat requirement of permanent, still or slow-flowing waters and nearby forests and grasslands is provided by the site through the many lagoons, herblands, sedgelands, swamp forests and coastal forests. Despite their requirement for permanent water for breeding, they also require terrestrial habitat (such as grasslands and forests), feeding mainly on terrestrial invertebrates such as beetles, termites, cockroaches, moths, butterflies and various insect larvae (DEWHA 2010b). Among the threats to the green and gold frog, habitat loss through stock grazing and irrigation are considered major (DEWHA 2010b). The ungrazed areas of the site provide sanctuary from these impacts, making it a key refuge for this species. The dwarf galaxias occurs in lowland areas in the north-east and north-west of Tasmania, on Flinders Island and in southern Victoria and South Australia (TSS 2006). Due to a declining total population and fragmented distributions of the dwarf galaxias, all known populations are important (TSS 2006). The species has declined and its genetic structure within the distribution is not yet known. Consequently, all areas where the species occurs are considered critical to survival (TSS 2006). The dwarf galaxias favours a shallow, stagnant, swampy environment with abundant aquatic plants and is typically found in still waters such as swamps, drains and backwaters of creeks and streams (DEWHA 2010b). The waters inhabited by this species are often temporary, drying up partially or completely during summer, and being replenished by rainfall or floodwaters from watercourses during the wetter months (DEWHA 2010b). This makes the Flood Plain Lower Ringarooma River Ramsar Site an ideal site for the dwarf galaxias, offering a range of permanent and seasonal waterbodies, mostly still or slow-flowing and many with abundant submerged vegetation. The extent and variety of waterbodies at the site, combined with the importance placed on all existing populations, highlights the importance of the site to the support of this species. The fairy tern is a marine listed species under the EPBC Act. In Australia, there are approximately 5000 to 6000 mature birds at around 170 sites, with estimates of 100 to a few hundred pairs in Tasmania (Birdlife International 2008). Disturbance by humans, dogs and vehicles, either causing the direct destruction of eggs or desertion of nests are key threats to the species, and the site offers refuge from these. The fairy tern has been recorded nesting at the site (see criterion 4). Australian grayling are an estuary dependent species which spends most of its lifecycle in freshwater, migrating between freshwater streams and the estuary to breed (DEWHA 2010b). The species is found in rivers with water ranging from clear to muddy and with substrates ranging from gravel to mud-bottomed. The species is described as occurring widely within Tasmania (DEWHA 2010b) and the importance of the site to the species is not known. The significant estuary and the large upstream river system makes this ideal habitat for the species, which is threatened at the national level. Criterion three: A wetland should be considered internationally important if it supports populations of plant and/or animal species important for maintaining the biological diversity of a particular biogeographic region. This criterion includes consideration of the site’s regional biodiversity, including biodiversity ‘hotspot’ status and regional endemism. The site has been described as important due to its diverse invertebrate fauna (RIS 2005). The series of shallow freshwater lagoons at the site are an important feeding and nesting place for many species of waterbirds. Approximately three kilometres of beaches are included in the site, from which a number of shorebirds have been recorded, including the hooded plover (Thinornis rubricollis), red-capped plover (Charadrius ruficapillus), greenshank (Tringa nebularia), red-necked stint (Calidris ruficollis), ruddy turnstone (Arenaria interpres), curlew sandpiper (Calidris ferruginea), black-fronted dotterel (Elseyornis melanops) and fairy tern (Sterna nereis) (Sally Bryant, personal communication). Approximately forty species of wetland dependent plants have been recorded at the site (see list below and Appendix 2). This criterion also includes species listed at the regional (in this case State) level. The site supports rare, poorly reserved and scientifically valuable species. It provides wetland habitat for two regionally threatened bird species and four regionally threatened flora species considered to be at risk in Tasmania. These are:
2.2.2 Assessment of remaining criteria An assessment of the remaining Ramsar listing criteria was undertaken to determine whether the site meets any criteria beyond the original listing. The results are as follows: Criterion four: A wetland should be considered internationally important if it supports plant and/or animal species at a critical stage in their life cycles, or provides refuge during adverse conditions. A number of migratory birds have also been recorded from the site, including eleven migratory birds listed in CAMBA, JAMBA, ROKAMBA and/or the CMS. These species include:
curlew sandpiper (Calidris ferruginea)
Quantitative data were not found for these species, however the provision of support for these species during migration constitutes support during a critical stage of their life cycle. The site also provides support for nesting shorebirds at a critical stage of their life cycle: breeding. Five beach nesting shorebirds have been recorded breeding within the site, including the little tern (which has migratory listing as noted above), and the fairy tern (IUCN red listed, as noted above) (Eric Woehler, Birds Tasmania, unpublished data). The site is known to ornithologists for its nesting by little terns and fairy terns, and its relatively low disturbance levels make breeding success per pair far more likely than elsewhere in Tasmania (Eric Woehler, Birds Tasmania, personal communication). Tasmanian mudfish (Galaxias cleaveri), Tasmanian whitebait (Lovettia sealli) and Australian grayling (Prototroctes maraena) have been recorded in the Ringarooma River. Mudfish habitat is swampy areas near the coast and the species is found mostly in still waters, heavily vegetated mud bottomed swamps and estuarine marshes. These habitats are under continual threat from drainage and reclamation (Read 1999). The juveniles of the species form part of the whitebait runs on their return from the sea in spring and they take up residence in the lower part of coastal streams, including the Ringarooma River (Read 1999). Tasmanian whitebait migrate into freshwater to breed. The larvae are then washed down into the sea. Read (1999) notes that this species was once the basis of an important commercial fishery, however since the 1940s populations have declined to the point where the fishery was closed from 1973 to 1990. The fishery has since been opened on a restricted basis. Australian grayling lives in coastal streams and rivers and needs to migrate to and from the sea. It spawns in autumn and when the larvae hatch they are swept down to the sea. Larval life is marine and juveniles return to rivers from the sea during spring, spending the rest of their life in rivers (Read 1999). The migration between fresh and marine waters highlights the importance of the estuarine habitat provided by the site and constitutes support for these species during a critical stage of their life cycle. This criterion is therefore met by the site and should be added to the listing criteria.
There are no data available to support the site meeting this criterion. Criterion six: A wetland should be considered internationally important if it regularly supports one percent of the individuals in a population of one species or subspecies of waterbird. There are no data available to support the site meeting this criterion. Criterion seven: A wetland should be considered internationally important if it supports a significant proportion of indigenous fish subspecies, species or families, life-history stages, species interactions and/or populations that are representative of wetland benefits and/or components and thereby contributes to global biological diversity. There are insufficient data to assess against this criterion. Criterion eight: A wetland should be considered internationally important if it is an important source of food for fishes, spawning ground, nursery and/or migration path on which fish stocks, either within the wetland or elsewhere, depend. There are no data available to support the site meeting this criterion. Criterion nine: A wetland should be considered internationally important if it regularly supports one percent of the individuals in a population of one species or subspecies of wetland-dependent non-avian animal species There are no data available to support the site meeting this criterion. |