Invasion of Lantana Camara L

Key Threatening Process Nomination Form - For adding a threatening process under the Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act) Nominated threatening process – summary of eligibility 6. Name of threatening process The invasion, establishment and spread of Lantana camara impacts negatively on native biodiversity including many EPBC listed species and communities. 7. Criteria under which the threatening process is eligible for listing Identify which criteria the threatening process meets (one or more). Please note that the information you provide in this nomination form should support your claim. For further details on the criteria, please refer to Part A of the Threatened Species Scientific Committee guidelines attached to this form. Criterion A - Evidence that the threatening process could cause a native species or ecological community to become eligible for listing in any category, other than conservation dependant. Criterion B - Evidence that the threatening process could cause a listed threatened species or ecological community to become eligible for listing in another category representing a higher degree of endangerment. Criterion C - Evidence that the threatening process adversely affects two or more listed threatened species (other than conservation dependant species) or two or more listed threatened ecological communities. Section 1 - Name and Description Conservation Theme 1. The conservation theme for the Lantana camara threatens a range of species and habitat types. assessment period commencing However, it is particularly prevalent along creek and river 1 October 2008 (for which systems where a year round supply of water can ensure the nominations close 31 March 2008) growth rates and germination success of this invasive species is ‘rivers, wetlands and are optimised. groundwater dependent species and ecosystems of inland Generally, riparian zones, swamps and floodplains in eastern NSW Australia’. and Queensland have been identified as being at risk from L. camara, including Swamp Tea-tree (Melaleuca irbyana) Forest of How does this nomination relate to South east Queensland (CE under the EPBC Act), Swamp Oak the conservation theme? Floodplain Forest of the NSW North Coast, Sydney Basin and South East Corner bioregions and Swamp Sclerophyll Forest on coastal floodplains of the NSW North Coast, Sydney Basin and South East Corner bioregions (Both E under the NSW TSC Act). Name 2. Name of nominated threatening The invasion, establishment and spread of Lantana camara process. The name should impacts negatively on native biodiversity including many EPBC accurately reflect the scope of the listed species and communities. process based on the description and evidence provided in this form. Description . Description of the threatening 3 Lantana (Lantana camara L. sens. lat., family Verbenaceae) is a process that distinguishes it from profusely branching, scrambling aromatic shrub 2–4 (up to 8) m any other threatening process, by tall and wide, with square-sectioned, often prickly cane-like reference to: Version 6 1 (i) its biological and non-biological stems (Swarbrick et al. 1995). L. camara is an 'aggregate components; species', or 'species complex', of which there are some 650 (ii) the processes by which those hybrid varieties in over 60 countries world-wide (Howard, 1969; components interact (if known). Parsons & Cuthbertson, 2001). This diverse range of varieties stem from several natural variants of L. camara across its presumed native range in the tropical Americas. In Australia at least 29 wild, cultivated and hybridised varieties have been identified. There are three major processes via which Lantana threatens biodiversity and ecosystem function in Australia. These are competition for habitat and resources; smothering; and prevention of recruitment thereby preventing the natural succession and recovery of native ecosystems. Sclerophyll woodlands, sclerophyll forests, rainforests and dry rainforests are all susceptible to Lantana establishment (Driscoll and Quinland 1985; Lamb 1988; Fensham et al 1994; Gentle and Duggin 1997a). Lantana will readily invade undisturbed sites and communities with open canopies. Lantana can also block succession following a disturbance, by out-competing native colonisers and thereby preventing natural recovery and decreasing biodiversity. Fensham et al. (1994) document declines in plant species richness with increasing levels of Lantana infestation in dry rainforest. Accumulation of heavy fuel loads along boundaries between savanna woodland and dry rainforest is also documented, encouraging fire and leading to significant canopy loss and edge erosion in the latter. Typically, Lantana then dominates the area of lost dry rainforest, rendering it prone to further fires. Alcova (1987) established a large decline (at least 70%) in inferred recruitment (being the number of native tree and shrub saplings present) in Lantana-infested areas of eucalypt woodland compared to Lantana-free areas. The generally suppressive effect of Lantana on a wide range of native species is attested by several studies (Gentle and Duggin 1998, Day et al. 2003) and a multitude of field observations. Swarbrick et al. (1995), citing observations by Driscoll and Quinlan (1985) that “eucalypt seedlings generally fail to establish under Lantana”, infers inhibition of germination through lack of light. Webb et al. (1972) reports Lantana blocking the succession of rainforest species for some 15 years in an artificially created (1957) gap in intact rainforest, and Stock (2004) affirms that the site was still Lantana-dominated in 2004. Lantana is also allelopathic, i.e. able to inhibit or suppress by chemical means the germination and/or growth of at least some competing plant species. Overseas glasshouse studies (Swarbrick et al. 1995; Day et al. 2003) and a substantive Australian field trial (Gentle and Duggin 1997b), provide support for this. It is suggested that Lantana may also change soil microhabitat through shading, self-mulching, and altered water and nutrient balances. Lamb (1988, cited in Swarbrick et al. 1995) identified an increase in soil nitrate in eucalypt woodland and a decline in other nutrients following Lantana invasion, to the benefit of the Lantana and other weeds, and to the detriment of some native species. Gentle and Duggin (1998) point to Lantana’s ability to out-compete for and sequester surface-soil nutrients, such as are made available by disturbance episodes, and verified experimentally Lantana’s ability to out-compete and suppress an analogous native coloniser of mesic forests (Choricarpia leptopetala, Myrtaceae). Lantana dominance is also likely to adversely affect the richness of some soil faunal assemblages. Cummings (2004) reports a reduced presence in Lantana-dominated vegetation of several functional groups of ant species, compared to adjacent ‘natural’ Version 6 2 (rainforest and sclerophyll) communities, and concludes this probably relates both to initial disturbance events and to the structure of Lantana-dominated vegetation that followed. Overseas research (Fernandes et al. 2001) points to a progressive loss of diversity among mycorrhizal arbuscular fungi in rainforest systems of Madagascar, correlated with a loss of vascular plant diversity and non-autochthonous secondary successions including Lantana camara-dominated associations. Lantana is not established as a causal mechanism but the ability of Lantana to arrest vegetation succession for decades (e.g. Lamb 1994, apropos subtropical rainforest), and to inhibit growth of at least some microorganisms (Parsons and Cuthbertson 2001), suggests it may also inhibit mycorrhizal recolonisation. Interactions between Lantana invasion and the presence of disturbance factors such as feral animals, human mediated disturbance, edge effects or extreme weather events causing canopy openings are also significant. For example, Fensham et al (1994) postulated a probable role in dry rainforest for feral pigs causing initial canopy openings that allow Lantana establishment. Pigs then avoid dense Lantana thickets, causing further openings in intact forest. The resulting Lantana thickets then, in this case, promote intense fire. Without the added impact of Lantana invasion, the initial disturbance events are unlikely to be significant enough to constitute a major threat to biodiversity in the region. The important factor that distinguishes Lantana’s impacts from other threatening processes is the magnitude of its current and potential impacts. Within this current distribution range, research indicates Lantana threatens 139 native plant species; 24 native animal species; and ten ecological communities currently listed under the EPBC Act. Analysis of the data associated with these species shows that 61 Vulnerable plant species and two Vulnerable animal species are likely to become listed as Endangered; 50 Endangered plant species and six Endangered animal species are likely to become listed as Critically Endangered; and one Critically Endangered plant species and one Critically Endangered animal species are likely to become extinct without Lantana control (DECC 2007; see http://www.environment.nsw.gov.au/pestsweeds/LantanaThreat ToBiodiversity.htm and further supporting evidence provided in section two). An additional 176 species (plants and animals) have also been identified that could become eligible for listing under the EPBC Act due to lantana. This includes 121 species that are already listed under NSW or Qld

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