Coastal wetlands of Victoria, south‐eastern Australia: providing the inventory and condition information needed for their effective management and conservation

Abstract

The effective management and conservation of coastal wetlands requires an appropriate typology to underpin classification and mapping, adequate inventory information, and a robust assessment of ecological condition and threats. Extensive and floristically diverse coastal wetlands occur along much of the coast of Victoria (south‐eastern Australia), but there are serious deficiencies in all these information requirements. Previously unanalysed data from the Victorian Biodiversity Atlas were used to revise the typology currently applied to coastal saltmarsh in Victoria. To supplement the single unit currently used for State‐endorsed mapping and inventory (EVC 9 Coastal Saltmarsh Aggregate), seven new Ecological Vegetation Classes are proposed to better reflect the floristic and structural diversity of coastal saltmarsh in south‐eastern Australia. Coastal saltmarsh is currently allocated the lowest conservation status (‘least concern’) across much of Victoria, and it is recommended that this be upgraded variously to the higher categories of ‘endangered’, ‘vulnerable’, or ‘rare’. A State‐wide inventory using the new typology, prepared using recently flown, high‐resolution aerial photographs and extensive ground‐truthing (212 person‐days), indicated that there were 19 212 ha of coastal saltmarsh of all types, 5177 ha of mangroves, and 3227 ha of EVC 10 Estuarine Wetland (a wetland type dominated by Juncus kraussii) in Victoria. On‐ground assessments undertaken across 30 geographic sectors of the coast indicated that coastal wetlands were confronted by a wide range of anthropogenic threats, which in many cases were quite different from those outlined in prior reviews of Australian wetland systems. Weed invasions were especially problematic, not so much of the exotic and highly publicized Spartina in the lower levels of tidal wetlands but from a wide range of exotic taxa in more elevated saltmarshes (e.g. tall wheat grass Lophopyrum ponticum). Copyright © 2014 John Wiley & Sons, Ltd.

Tidal marsh erosion and accretion trends following invasive species removal, Tamar Estuary, Tasmania

“…Negative consequences subsequently became recognised, such as replacement of native vegetation, and destruction of important migratory shorebird and waterfowl habitat Strong and Ayres, 2013;Boon et al, 2014). In China, three introduced Spartina species are estimated to have caused annual economic losses of US 2000 million dollars, and are now declared as notorious invasive species (Sun et al, 2015).…”

“…In China, three introduced Spartina species are estimated to have caused annual economic losses of US 2000 million dollars, and are now declared as notorious invasive species (Sun et al, 2015). In Australia, S. anglica became considered to be an invasive species (Laegdsgaard, 2006;Boon et al, 2014), threatening the ecological integrity of estuarine wetlands of international importance (Wells, 1995;Doody, 2008). Furthermore, sediment buildup and dense vegetation impacted coastal access, brought threats to coastal infrastructure and aquaculture Doody, 2008), and resulted in estuarine morphological transformation .…”

Saltmarsh conservation through inventory, biogeographic analysis and predictions of change: Case of Tasmania, south‐eastern Australia

“…Saltmarsh clusters were further aggregated at coarser scales, as complexes, at 1 : 25,000–1 : 100,000. Each complex was made up of several clusters, and was variously defined by catchment, rainfall, geomorphology and similar land‐use, equivalent to the sectors defined by Boon et al (). Sixty‐one complexes were identified and formed the spatial units for biogeographic analysis.…”

“…Mcowen et al, ). There is also a lack of high‐resolution inventories of saltmarsh covering large regions of Australia (Kelleway et al, ; Rogers et al, ), with the exception being Victoria (Boon et al, ). Inventories are necessary to facilitate legislative protection (Prahalad, Whitehead, Latinovic, & Kirkpatrick, ; Rogers et al, ), and enable biogeographic assessments to inform conservation (e.g.…”

“…Inventories are necessary to facilitate legislative protection (Prahalad, Whitehead, Latinovic, & Kirkpatrick, ; Rogers et al, ), and enable biogeographic assessments to inform conservation (e.g. Boon et al, ; Isacch et al, ).…”