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Cane toads introduced to Queensland in 1935, are major environmental pests in Western Australia, having arrived here in February 2009. The Liberal National Government released a 10-year Cane Toad Strategy for Western Australia in 2009. Over the first five years of the strategy, much has been achieved and the government has invested more than $7.8 million in on –ground activities and research to help control the spread of can toads. With a range of stakeholders, including community groups, universities, the Australian Government, local shires, Indigenous groups and others, the State of Government has implemented many new can toad management programs including a field-based cane toad surveillance and response team, strengthened quarantine measures, a free-call hotline to report cane toad sightings and cane toad drop off points. Major biological survey work has provided benchmark information on important island wildlife populations that need priority protection from cane toad. Biological controls are also being researched for the survival of native wildlife species in the short and medium terms and management of cane toads in the longer term. Educating the community has prevented new populations from establishing in Perth and elsewhere. Detector dog specially trained to sniff out cane toads is a proactive measure to stem the spread of this noxious pest. This is a review and update on the original 10 year strategy to review and update the strategy to reflect progress in implementation, the current status of cane toads in WA and results of ongoing research, and to refocus its aims and objectives. Cost effective activities and an integrated approach with other initiatives across WA, such as the $81.5 million Kimberley Science and Conservation Strategy, are required. The revised Cane Toad Strategy for Western Australia 2014-2019 will ensure the available information is used to inform Wa’s continued management of cane toads.

Rhinella marina is a Neotropical toad that has been introduced widely worldwide. Its toxic effects to frog-eating predators threaten the native and domestic fauna of some regions where it has been introduced. Despite previous studies suggesting two genetically distinct cryptic species within R. marina, one east and one west of the Andes, its taxonomic status remained unresolved due to the absence of morphological complementary evidence. For the first time, data from two mitochondrial genes (ND3 and CR) and 23 morphometric landmarks are combined to evaluate the taxonomic status of this species. Our results support the hypothesis of two separate evolutionary lineages within R. marina and demonstrate that these lineages have significantly diverged in skull shape. We identified two distinct morphotypes, one eastern and one Andean western, with no overlapping morphospaces. The geographic pattern of genetic variation was consistent with a stable structured population with no evidence of recent demographic or geographic expansions. The concordance between the observed geographic patterns in morphometric and genic traits calls for the recognition of two species under R. marina name.

It is with great pleasure that I send out the Soundbites for the year of 2018. For most of us this time of the year is a mix of trying to get everything completed at work on time and planning what we are doing with our families over the up-coming festive season.

Invasive species are widespread and can have devastating effects on biota, especially insular biota. Invasive species eradications are increasingly employed to promote island recovery to preinvasion states. However, it remains unclear if additional restoration actions may be required on islands that were once heavily reliant on seabird guano for ecosystem functions. Active seabird augmentation has been suggested as necessary to exact ecosystem recovery on contemporary timescales in some cases. I use two experiments on offshore islands in Cook Strait, New Zealand, to test the hypothesis that seabird restoration will restore island ecosystem functioning following invasive rodent removal. The first is a small-scale single-island fertilization experiment that simulates seabird recovery.

Native forest species exhibit a well-known range of ecological roles with respect to natural disturbance regimes, from pioneer phase to mature phase, and they regenerate from a range of sources, including dormant seeds, seed rain, pre-established juveniles, and resprouts from damaged adults. In contrast, the ecological roles of invasive, non-indigenous species in forest communities after natural disturbances are not well understood. Some previous studies of invasive species have emphasized their weedy nature and their ability to colonize anthropogenic disturbances. Tropical hardwood hammock forest in southern Florida experience frequent disturbance by hurricanes. Our studies of forest regneration during two years following a recent severe hurricane suggest that invasive non-indigenous forest species exhibit the same range of ecological roles as native forest regeneration during two years following a recent severe hurricane suggest that invasive non-indigenous forest species exhibit the same range of ecological roles as native forest species and compete with native species for particular kinds of regeneration opportunities. To study ecological roles of non-indegenous species in regenerating forests after Hurricane Andrew, we set up four large study areas at each of three study sites that had differing amounts of hurricane-caused canopy disturbance. There were two pairs of 30 X 60 m research plots per site, and in each pair there was one control plot and one restoration plot; restoration areas were subject to an aggressive management program, focused on reducing non-indigenous vine cover. Within these study areas we subsampled vegetation in small study plots that were regularly spaced, and conducted vegetation censuses in April (the end of the dry season) and October (the end of the rainy season) for 2 yr, beginning in April 1993. We found that the source of regeneration for forest species was dependent upon the amount of canopy disturbance, the time since disturbance, and the autecology of the constituent species. Overall, 28% of the 90 species were non-indigenous: 34% of the vines (N=32) and 24% of other life-forms (N=58). Non-indigenous vines seemed to have a special role; not only could they compete with native vines, but they could also negatively affect the regeneration of other natives from a diverse array of sources including pre-established juveniles and resprouts from damaged adults. Both native and non-indigenous vine cover in unmanipulated study areas increased following the hurricane. Non-indigenous vine species had higher cover than native vine species, and many species formed dense "blankets." Non-indigenous species in general (not just vines) did not differ significantly from native species in seed mass, nor were they restricted to the pioneer type of life history. Many non-indigneous species had invaded forests prior to hurricane disturbance and had their own banks of pre-established juveniles; others recruited from dormant seeds, and seed rain, and/or respouts from pre-established adults. Based on information on source of regeneration and impact on native species, we propose a classification scheme for functional roles of non-indigenous invasive species in forests. To investigate whether non-indigenous taxa had roles in other geographic regions similar to those they had in Florida, we reviewed literature for 50 taxa belonging to genera that have species known to be invasive in southern Florida. We found that these taxa were invsive or had cogeners that were invsive in other geographic regions (Western Australis, the Mariana Islands, Hawaii, the rMascarene Islands, and South Africa). We propose that taxa predominantly retain their invasive, functional-role type across regions. Thus, studies of ecological roles of invasive species with respect to natural disturbance regimes in one region may help us predict invasive roles in other regions.

The last two decades have seen an upsurge in research into the potential synergies between invasive species and climate change, with evidence emerging of increased invader success under climate change. All stages along the naturalization-invasion continuum are likely to be affected, from the introduction and establishment of alien species to their spread and transition to serious invaders. A key question is whether alien plants will have a relative advantage under climate change conditions. So far, evidence for differential responses of alien invasive and native species to climate change drivers (elevated CO2) and outcomes (increasing temperature, changing rainfall patterns, changes in disturbance regimes) is mixed. Although alien invasive plants appear to be more responsive to elevated CO2 than many native species, plant response to elevated CO2 and other climate change components is dependent on environmental conditions and resource availability. Similarly, correlative modelling of species-climate relationships has not revealed clear evidence that invasive plants are likely to be able to increase the extent of suitable habitat under future climates any more than their native counterparts. We suggest that the most important driver of a shift to alien-dominated vegetation under climate change will be the superior capacity of alien invasive plants to take advantage of colonisation opportunities arising from climate change, such as extreme climatic events, changes in disturbance regimes, and widespread reduction in vegetation resilience as range margin populations decline. There are substantial challenges ahead for managing invasive plants under future climates. Weed risk assessment and management approaches must incorporate consideration of future climatic conditions. Most importantly, we will need a shift in management approaches away from a focus on the control of undesirable alien plant species to building resilience of resident vegetation assemblages, in association with targeted monitoring and early eradication of alien plant species.

Disturbances are a primary facilitator of the growth and spread of invasive species. However, the effects of large-scale disturbances, such as hurricanes and tropical storms, on the broad geographic patterns of invasive species growth and spread have not been investigated. We used historical aerial imagery to determine the growth rate of invasive Phragmites australis patches in wetlands along the Atlantic and Gulf Coasts of the United States. These were relatively undisturbed wetlands where P. australis had room for unrestricted growth. Over the past several decades, invasive P. australis stands expanded in size by 6–35% per year. Based on tropical storm and hurricane activity over that same time period, we found that the frequency of hurricane-force winds explained 81% of the variation in P. australis growth over this broad geographic range. The expansion of P. australis stands was strongly and positively correlated with hurricane frequency. In light of the many climatic models that predict an increase in the frequency and intensity of hurricanes over the next century, these results suggest a strong link between climate change and species invasion and a challenging future ahead for the management of invasive species.

Disturbances that remove primary producers and alter substrate chemistry commonly influence ecosystem carbon dynamics. Because coastal wetlands are especially effective in sequestering carbon, quantifying how disturbances may alter their ability to perform this climate-regulating function is important for assessing their carbon storage potential. Here, we quantified soil respiration, litter decomposition, and soil organic carbon (SOC), as a proxy for carbon storage, in areas disturbed by invasive feral hogs Sus scrofa and in adjacent, undisturbed areas within 3 southeastern US salt marshes. Contrary to our hypothesis that hog overturning of soils would stimulate soil respiration, this metric was lower and both surface and subsurface litter decomposition rates were similar in disturbed relative to undisturbed areas across all sites. SOC was lower in disturbed versus undisturbed areas at 2 sites as hypothesized, but higher at 1 site. Surveys and analyses reveal that lower and less variable infauna, plant, and benthic algae densities likely suppressed soil respiration in hog-disturbed versus undisturbed areas, while the offsetting effects of lower invertebrate densities and higher soil temperature likely caused decomposition to be consistent within and outside of disturbed areas. . These findings suggest that hog removal of plants and disruption of soils can cause tracts of marsh to transition from carbon sinks to sources where these disturbances are intense enough to prohibit rapid plant recovery and promote the gradual respiration of carbon stocks from denuded soils.

Outbreaks of the corallivorous crown-of-thorns seastar Acanthaster planci (COTS) represent one of the greatest disturbances to coral reef ecosystems in the Indo-Pacific, affecting not only coral reefs but also the coastal communities which rely on their resources. While injection approaches are increasingly used in an attempt to control COTS densities, most of them display severe drawbacks including logistical challenges, high residual environmental impacts or low cost-effectiveness. We tested a new alternative control method based upon acidic injections of cheap, 100% natural products. We investigated the lethal doses, intraand inter-specific disease transmission and immune responses of COTS when injected with fresh lime juice (extracted from local Citrus arantifolia) and white spirit vinegar. High COTS mortality was achieved with small volumes: 10–20 ml per seastar induced death in 89%/ 97% of injected specimens after an average 34.3 h/29.8 h for lime juice and vinegar respectively. Highest efficiency was reached for both solutions with double shots of (2 × 10 ml) in two different areas on the body: 100% mortality occurred within 12–24 h, which is similar or faster compared with other current injection methods. Multiple immune measures suggested that death was very likely caused by pH stress from the acidic solutions rather than a bacterial infection. Contagion to either conspecifics or a variety of other reef species was not observed, even at COTS densities 15 times higher than the highest naturally reported. 10 to 20 l lime juice/vinegar could kill up to a thousand COTS at a cost of less than 0.05 USD per specimen; no permits or special handling procedures are required. We conclude that injections of lime juice and vinegar offer great advantages when compared to current best practises and constitute a cheap and natural option for all reefs affected by COTS

On 11 November 2014, a remarkable event occurred. President Barack Obama of the United States and President Xi Jinping of China announced a bilateral agreement to reduce the emission of greenhouse gases (GHGs) that cause global warming by their respective nations. On 12 December 2015, a year and a month later, representatives of 195 countries attending the 21st Conference of the Parties of the United Nations Framework Convention on Climate Change meeting in Paris, France, announced the Paris Climate Agreement. The goal of the Paris Climate Agreement is to limit the future emission of GHGs such that the rise in global mean surface temperature will be no more than 1.5 °C (target) or 2.0 °C (upper limit) above the pre-industrial level. The Paris Climate Agreement utilizes an approach for reducing the emissions of GHGs that is distinctly different than earlier efforts. The approach for Paris consists of a series of Intended Nationally Determined Contributions (INDCs), submitted by the world’s nations, reflecting either a firm commitment (unconditional INDCs) or a plan contingent on financial and/or technological support (conditional INDCs). The Obama–Xi announcement was instrumental in the framing of the Paris Climate Agreement. The INDCs submitted by the USA and China were built closely upon the November 2014 bilateral announcement. China and the USA rank number one and two, respectively, in terms of national emission of GHGs. Practically speaking, unified global action to combat global warming required these two nations to get on the same page.