Climate Change Hotspot Research Articles

Welcome strangers: Southern range extensions for seven heterobranch sea slugs (Mollusca: Gastropoda) on the subtropical east Australian coast, a climate change hot spot

The south eastern Australian coast is a recognised climate change hot spot and, as a result, poleward shifts in distribution are expected for many taxa. Between March 2015 and January 2016, we observed seven species of sea slug south of their previously recorded range. Each species has <10 records from the eastern Australian coast, four are first observations for the state of New South Wales and two represent southernmost records for the southern hemisphere. As such, these records form an important base for detecting any further shifts in range.

Living with Earthquakes and Angry Deities at the Himalayan Borderlands

The Indian Himalayan Region, a climate change hotspot, is witnessing a massive surge in hydropower development alongside a dramatic rise in natural hazard events. This article explores indigenous people's response to this intersection of concerns around hazards and contentious development beyond more legible instances of social movements or resistance. Through an ethnographic case study located in the Eastern Himalayan state of Sikkim, the site of a 6.9 magnitude earthquake, controversial hydropower projects, and an indigenous antidam protest, I show how people's relationship with a sacred, animate landscape is not easily translatable into the clear goals of environmental politics. Antidam activists and environmentalists link growing ecological precarity in Sikkim to state-led hydropower construction, but for many lay indigenous people, these earthquakes raise deeper cultural anxieties. I demonstrate how these anxieties are grounded in a longer history of the contested relationship between marginalized peoples and hegemonic state and nonstate powers, a relationship that continues in the fraught relationship of the Himalayan margins to the Indian state. I argue that critical engagements with indigenous environmentalism must be in dialogue with diverse interpretations and registers of loss and erasure. In this I follow recent calls to decolonize the Anthropocene that demand that we move beyond a politics of urgency to examine the slow, historical processes of erasure under colonialism and imperialism. I highlight these narratives to argue for a more holistic approach to the uneven impacts of climate change on mountainous environments and their inhabitants.

Recent shallowing of the thaw depth at Crater Lake, Deception Island, Antarctica (2006–2014)

The Western Antarctic Peninsula region is one of the hot spots of climate change and one of the most ecologically sensitive regions of Antarctica, where permafrost is near its climatic limits. The research was conducted in Deception Island, an active stratovolcano in the South Shetlands archipelago off the northern tip of the Antarctic Peninsula. The climate is polar oceanic, with high precipitation and mean annual air temperatures (MAAT) close to −3°C. The soils are composed by ashes and pyroclasts with high porosity and high water content, with ice-rich permafrost at −0.8°C at the depth of zero annual amplitude, with an active layer of about 30cm. Results from thaw depth, ground temperature and snow cover monitoring at the Crater Lake CALM-S site over the period 2006 to 2014 are analyzed. Thaw depth (TD) was measured by mechanical probing once per year in the end of January or early February in a 100×100m with a 10m spacing grid. The results show a trend for decreasing thaw depth from ci. 36cm in 2006 to 23cm in 2014, while MAAT, as well as ground temperatures at the base of the active layer, remained stable. However, the duration of the snow cover at the CALM-S site, measured through the Snow Pack Factor (SF) showed an increase from 2006 to 2014, especially with longer lasting snow cover in the spring and early summer. The negative correlation between SF and the thaw depth supports the significance of the influence of the increasing snow cover in thaw depth, even with no trend in the MAAT. The lack of observed ground cooling in the base of the active layer is probably linked to the high ice/water content at the transient layer. The pyroclastic soils of Deception Island, with high porosity, are key to the shallow active layer depths, when compared to other sites in the Western Antarctic Peninsula (WAP). These findings support the lack of linearity between atmospheric warming and permafrost warming and induce an extra complexity to the understanding of the effects of climate change in the ice-free areas of the WAP, especially in scenarios with increased precipitation as snow fall.

Global climate change and local watershed management as potential drivers of salinity variation in a tropical coastal lagoon (Laguna de Terminos, Mexico)

The wide range of ecological goods and services provided by tropical coastal lagoons and wetlands are under considerable pressure due to the synergistic effects of local anthropogenic impact and global climate change. In transitional waters, salinity is a key driver of ecological processes mostly depending on the balance between marine and river inputs, a balance that can be significantly modified by climate change and by anthropogenic alteration of the watershed. Mesoamerica being considered as a climate change hot-spot and as an ecoregion strongly vulnerable to global change, our study aimed at analyzing the relationship between salinity, river runoff, and rainfall variability in a tropical coastal lagoon and to assess the respective influence of climate change and watershed management. The study focusing on the large and shallow coastal lagoon of Laguna de Terminos in south eastern Mexico established: (1) the variability in salinity distribution along the yearly cycle and the occurrence of a high salinity anomaly period during the wet season of 2009; (2) the relationship between lagoon waters salinity and river inputs further underlying the anomalous situation encountered in 2009; (3) a long term increase in river discharge during the past 60 years, indicating potential salinity decrease in the lagoon during that same period; (4) an absence of any change in rainfall linking the increase in runoff to watershed management rather than long term trend in climate change. Additionally, the specific context of the 2009–2010 Central-Equatorial Pacific El Nino is underlined and the potential relationship between river discharge and ENSO is discussed. Those results should be of significant practical value to decision-makers who are often keen to point the finger at global climate change when local environmental management is also and sometime most significantly responsible.

Can Continental Shelf River Plumes in the Northern and Southern Gulf of Mexico Promote Ecological Resilience in a Time of Climate Change?

Deltas and estuaries built by the Mississippi/Atchafalaya River (MAR) in the United States and the Usumacinta/Grijalva River (UGR) in Mexico account for 80 percent of all Gulf of Mexico (GoM) coastal wetlands outside of Cuba. They rank first and second in freshwater discharge to the GoM and owe their natural resilience to a modular geomorphology that spreads risk across the coast-scape while providing ecosystem connectivity through shelf plumes that connect estuaries. Both river systems generate large plumes that strongly influence fisheries production over large areas of the northern and southern GoM continental shelves. Recent watershed process simulations (DLEM, MAPSS) driven by CMIP3 General Circulation Model (GCM) output indicate that the two systems face diverging futures, with the mean annual discharge of the MAR predicted to increase 11 to 63 percent, and that of the UGR to decline as much as 80 percent in the 21st century. MAR delta subsidence rates are the highest in North America, making it particularly susceptible to channel training interventions that have curtailed a natural propensity to shift course and deliver sediment to new areas, or to refurbish zones of high wetland loss. Undoing these restrictions in a controlled way has become the focus of a multi-billion-dollar effort to restore the MAR delta internally, while releasing fine-grained sediments trapped behind dams in the Great Plains has become an external goal. The UGR is, from an internal vulnerability standpoint, most threatened by land use changes that interfere with a deltaic architecture that is naturally resilient to sea level rise. This recognition has led to successful efforts in Mexico to protect still intact coastal systems against further anthropogenic impacts, as evidenced by establishment of the Centla Wetland Biosphere Preserve and the Terminos Lagoon Protected Area. The greatest threat to the UGR system, however, is an external one that will be imposed by the severe drying predicted for the entire Mesoamerican “climate change hot-spot”, a change that will necessitate much greater international involvement to protect threatened communities and lifeways as well as rare habitats and species.

Heavy Metals in Surface Soils in the Upper Reaches of the Heihe River, Northeastern Tibetan Plateau, China.

The upper reaches of the Heihe River have been regarded as a hotspot for phytoecology, climate change, water resources and hydrology studies. Due to the cold-arid climate, high elevation, remote location and poor traffic conditions, few studies focused on heavy metal contamination of soils have been conducted or reported in this region. In the present study, an investigation was performed to provide information regarding the concentration levels, sources, spatial distributions, and environmental risks of heavy metals in this area for the first time. Fifty-six surface soil samples collected from the study area were analyzed for Cr, Mn, Ni, Cu, Zn, As, Cd and Pb concentrations, as well as TOC levels. Basic statistics, concentration comparisons, correlation coefficient analysis and multivariate analyses coupled with spatial distributions were utilized to delineate the features and the sources of different heavy metals. Risk assessments, including geoaccumulation index, enrichment factor and potential ecological risk index, were also performed. The results indicate that the concentrations of heavy metals have been increasing since the 1990s. The mean values of each metal are all above the average background values in the Qinghai Province, Tibet, China and the world, except for that of Cr. Of special note is the concentration of Cd, which is extremely elevated compared with all background values. The distinguished ore-forming conditions and well-preserved, widely distributed limestones likely contribute to the high Cd concentration. Heavy metals in surface soils in the study area are primarily inherited from parent materials. Nonetheless, anthropogenic activities may have accelerated the process of weathering. Cd presents a high background concentration level and poses a severe environmental risk throughout the whole region. Soils in Yinda, Reshui daban, Kekeli and Zamasheng in particular pose threats to the health of the local population, as well as that of livestock and wildlife.

An illustrated inventory of the sea slugs of New South Wales, Australia (Gastropoda: Heterobranchia)

Although the Indo-Pacific is the global centre of diversity for the heterobranch sea slugs, their distribution remains, in many places, largely unknown. On the Australian east coast, their diversity decreases from approximately 1000 species in the northern Great Barrier Reef to fewer than 400 in Bass Strait. While occurrence records for some of the more populated sections of the coast are well known, data are patchy for more remote areas. Many species have very short lifecycles, so they can respond rapidly to changes in environmental conditions. The New South Wales coast is a recognised climate change hot-spot and southward shifts in distribution have already been documented for several species. However, thorough documentation of present distributions is an essential prerequisite for identifying further range extensions. While distribution data are available in the public realm, much is also held privately as photographic collections, diaries and logs. This paper consolidates the current occurrence data from both private and public sources as part of a broader study of sea slug distribution in south-eastern Australia and provides an inventory by region. A total of 382 species, 155 genera and 54 families is reported from the mainland coast of New South Wales.

Resistance and resilience to changing climate of Tuscany and Valpolicella wine grape growing regions in Italy

Global climate change poses new challenges for plant species, including new and complex combinations of environmental conditions to which plants should adjust and adapt. Mediterranean ecosystems are recognized biodiversity hotspots, but are also global climate change hotspots due to the concerted action of multiple environmental drivers. The Italian Peninsula presents a wide range of all these site-related elements influencing grapevine performance. From a climatic perspective, it delivers a relatively large set of mesoclimates, spanning from dryer regions, in the inner south, to more humid regions, in the northwest and northeast. Topography and soils are also quite distinct throughout the peninsula, ranging from extended flatland areas to steep mountainous regions, each with very different soil characteristics, which may influence crop selection and settlements in each region. All these elements are reflected in the different varieties grown throughout the peninsula.This study aims to provide an improved assessment of the practical adaptation options for the viticulture of Tuscany and of Valpolicella and what could be the strength and resilience to climate change of grapevine varieties in these areas. According to the models tested, Italian viticulture is able to adapt better than other countries to global warming, as the placing at various altitudes up in the high hills and mountains sets off the mechanism called resilience.

Empirical evidence for different cognitive effects in explaining the attribution of marine range shifts to climate change

AbstractThe changing geographical distribution of species, or range shift, is one of the better documented fingerprints of climate change in the marine environment. Range shifts may also lead to dramatic changes in the distribution of economic, social, and cultural opportunities. These challenge marine resource users' capacity to adapt to a changing climate and managers' ability to implement adaptation plans. In particular, a reluctance to attribute marine range shift to climate change can undermine the effectiveness of climate change communications and pose a potential barrier to successful adaptation. Attribution is a known powerful predictor of behavioural intention. Understanding the cognitive processes that underpin the formation of marine resource users' beliefs about the cause of observed marine range shift phenomena is therefore an important topic for research. An examination of the attribution by marine resource users of three types of range shifts experienced in a marine climate change hotspot in southeast Australia to various climate and non-climate drivers indicates the existence of at least three contributing cognitions. These are: (i) engrained mental representations of environmental phenomena, (ii) scientific complexity in the attribution pathway, and (iii) dissonance from the positive or negative nature of the impact. All three play a part in explaining the complex pattern of attribution of marine climate change range shifts, and should be considered when planning for engagement with stakeholders and managers around adaptation to climate change.

Rapid warming and drought negatively impact population size and reproductive dynamics of an avian predator in the arid southwest.

Avian communities of arid ecosystems may be particularly vulnerable to global climate change due to the magnitude of projected change for desert regions and the inherent challenges for species residing in resource limited ecosystems. How arid-zone birds will be affected by rapid increases in air temperature and increased drought frequency and severity is poorly understood because avian responses to climate change have primarily been studied in the relatively mesic northern temperate regions. We studied the effects of increasing air temperature and aridity on a Burrowing Owl (Athene cunicularia) population in the southwestern United States from 1998 to 2013. Over 16 years, the breeding population declined 98.1%, from 52 pairs to 1 pair, and nest success and fledgling output also declined significantly. These trends were strongly associated with the combined effects of decreased precipitation and increased air temperature. Arrival on the breeding grounds, pair formation, nest initiation, and hatch dates all showed significant delays ranging from 9.4 to 25.1 days over 9 years, which have negative effects on reproduction. Adult and juvenile body mass decreased significantly over time, with a loss of 7.9% mass in adult males and 10.9% mass in adult females over 16 years, and a loss of 20.0% mass in nestlings over 8 years. Taken together, these population and reproductive trends have serious implications for local population persistence. The southwestern United States has been identified as a climate change hotspot, with projections of warmer temperatures, less winter precipitation, and an increase in frequency and severity of extreme events including drought and heat waves. An increasingly warm and dry climate may contribute to this species' decline and may already be a driving force of their apparent decline in the desert southwest.

Future climate of the Carpathians: climate change hot-spots and implications for ecosystems

The Carpathians are the largest European mountain range and harbour exceptional biodiversity. However, recent and anticipated changes in climate along with rapid social and economic development suggest that the region’s values may not be sustained. We strived to identify the main regional climate change hot-spots and evaluate the distribution of climatically exposed land-use types and ecosystems. The analysis was based on 10 climate models driven by the emission scenario A1B. To identify the hot-spots, we adopted a methodology based on change trajectories in a multidimensional climate space. Three hot-spots were in the Western Carpathians (Czech Republic, Slovakia, and Hungary), two were in Ukraine, and three were in the Romanian and Serbian Carpathians. Regions with the highest aggregate climate exposure (i.e. above 70 % of the regional range) were mostly covered by broadleaved forests (39 %), agricultural land (30 %), and pastures and woodlands (15 %). These regions also contained 15 % of protected areas and 36 % of the total human population in the Carpathians. While growing season length was the main factor affecting hot-spot magnitude in the north-west, precipitation-related variables were the main factors in the east and south. Analysis of inter-climate model variability indicated that the level of confidence in hot-spot position and magnitude differed among hot-spots. In addition to identifying a large-scale regional pattern of climate change, we showed that there are sub-regions with remarkably high climate exposure. The hot-spot distribution in lower elevations suggests that Carpathian ecosystems in water-limited environment may be particularly exposed to climate change.

Climate change and economic growth: An intertemporal general equilibrium analysis for Egypt

This study advances the state of the art in country-level computable general equilibrium analysis for climate change impact and adaptation analysis by incorporating forward-looking expectations. The analytic framework is used to explore the long-run growth prospects for Egypt in a changing climate. Based on a review of existing estimates of climate change impacts on agricultural productivity, labour productivity and the potential losses due to sea-level rise for the country, the model is used to simulate the effects of climate change on aggregate consumption, investment and income up to 2050. Available cost estimates for adaptation investments are employed to explore adaptation strategies.The simulation analysis suggests that in the absence of policy-led adaptation investments, real GDP towards the middle of the century will be 6.5% lower than in a hypothetical baseline without climate change. A combination of adaptation measures, that include coastal protection investments for vulnerable sections along the low-lying Nile delta, support for changes in crop management practices and investments to raise irrigation efficiency, could reduce the GDP loss in 2050 to around 2.6%.Further work along these lines for developing countries in climate change hotspot regions deserves a high priority on the research agenda in economic modelling.

Productivity changes in the Mediterranean Sea for the twenty-first century in response to changes in the regional atmospheric forcing

The Mediterranean Sea is considered as a hotspot for climate change because of its location in the temperate region and because it is a semi-enclosed basin surrounded by highly populated and developed countries. Some expected changes include an increase in air temperature and changes in the periodicity and spatial distribution of rainfall. Alongside, demographic and politics changes will alter freshwater quantity and quality. All these changes will have an impact on the ecological status of marine ecosystems in the basin. We use a 3D hydrodynamic-biogeochemical coupled model of the entire Mediterranean Sea to explore potential changes in primary productivity (mean values and spatial distribution) under two emission scenarios (rcp4.5 and rcp8.5).To isolate the effects of changes in atmospheric conditions alone, in this ensemble of simulations rivers conditions (water flow and nutrient concentrations) are kept unchanged and equal to its climatological values for the last 10 years. Despite the significant warming trend, the mean integrated primary production rate in the entire basin remains almost unchanged. However characteristic spatial differences are consistently found in the different simulations. The western basin becomes more oligotrophic associated to a surface density decrease (increase stratification) because of the influence of the Atlantic waters which prevents surface salinity to increase. In the eastern basin, on the contrary, all model runs simulates an increase in surface production linked to a density increase (less stratification) because of the increasing evaporation rate. The simulations presented here demonstrate the basic response patterns of the Mediterranean Sea ecosystem to changing climatological conditions. Although unlikely, they could be considered as a ‘baseline’ of expected consequences of climatic changes on marine conditions in the Mediterranean.

Benthic Oxygen Uptake in the Arctic Ocean Margins - A Case Study at the Deep-Sea Observatory HAUSGARTEN (Fram Strait).

The past decades have seen remarkable changes in the Arctic, a hotspot for climate change. Nevertheless, impacts of such changes on the biogeochemical cycles and Arctic marine ecosystems are still largely unknown. During cruises to the deep-sea observatory HAUSGARTEN in July 2007 and 2008, we investigated the biogeochemical recycling of organic matter in Arctic margin sediments by performing shipboard measurements of oxygen profiles, bacterial activities and biogenic sediment compounds (pigment, protein, organic carbon, and phospholipid contents). Additional in situ oxygen profiles were performed at two sites. This study aims at characterizing benthic mineralization activity along local bathymetric and latitudinal transects. The spatial coverage of this study is unique since it focuses on the transition from shelf to Deep Ocean, and from close to the ice edge to more open waters. Biogeochemical recycling across the continental margin showed a classical bathymetric pattern with overall low fluxes except for the deepest station located in the Molloy Hole (5500 m), a seafloor depression acting as an organic matter depot center. A gradient in benthic mineralization rates arises along the latitudinal transect with clearly higher values at the southern stations (average diffusive oxygen uptake of 0.49 ± 0.18 mmol O2 m-2 d-1) compared to the northern sites (0.22 ± 0.09 mmol O2 m-2 d-1). The benthic mineralization activity at the HAUSGARTEN observatory thus increases southward and appears to reflect the amount of organic matter reaching the seafloor rather than its lability. Although organic matter content and potential bacterial activity clearly follow this gradient, sediment pigments and phospholipids exhibit no increase with latitude whereas satellite images of surface ocean chlorophyll a indicate local seasonal patterns of primary production. Our results suggest that predicted increases in primary production in the Arctic Ocean could induce a larger export of more refractory organic matter due to the longer production season and the extension of the ice-free zone.

Water supply sustainability and adaptation strategies under anthropogenic and climatic changes of a meso-scale Mediterranean catchment

Assessing water supply sustainability is crucial to meet stakeholders' needs, notably in the Mediterranean. This region has been identified as a climate change hot spot, and as a region where water demand is continuously increasing due to population growth and the expansion of irrigated areas. The Hérault River catchment (2500km2, France) is a typical example and a negative trend in discharge has been observed since the 1960s. In this context, local stakeholders need to evaluate possible future changes in water allocation capacity in the catchment, using climate change, dam management and water use scenarios. A modelling framework that was already calibrated and validated on this catchment over the last 50years was used to assess whether water resources could meet water demands at the 2030 horizon for the domestic, agricultural and environmental sectors. Water supply sustainability was evaluated at the sub-basin scale according to priority allocations using a water supply capacity index, frequency of unsatisfactory years as well as the reliability, resilience and sustainability metrics. Water use projections were based on the evolution of population, per-unit water demand, irrigated areas, water supply network efficiency, as well as on the evaluation of a biological flow. Climate projections were based on an increase in temperature up to 2°C and a decrease in daily precipitation by 20%. Adaptation strategies considered reducing per-unit water demand for the domestic sector and the importation of water volume for the agricultural sector. The dissociated effects of water use and climatic constraints on water supply sustainability were evaluated. Results showed that the downstream portions would be the more impacted as they are the most exploited ones. In the domestic sector, sustainability indicators would be more degraded by climate change scenarios than water use constraints. In the agricultural sector the negative impact of water use scenarios would be stronger. The environmental sector would be hardly satisfied especially in summer with low resilience levels. The adaptation strategies considered in this study would not be sufficient to cope with both anthropogenic and climate changes. Other strategies were discussed based on known examples in the Mediterranean context.

Observed climate change hotspots

AbstractWe quantify climate change hotspots from observations, taking into account the differences in precipitation and temperature statistics (mean, variability, and extremes) between 1981–2010 and 1951–1980. Areas in the Amazon, the Sahel, tropical West Africa, Indonesia, and central eastern Asia emerge as primary observed hotspots. The main contributing factors are the global increase in mean temperatures, the intensification of extreme hot‐season occurrence in low‐latitude regions and the decrease of precipitation over central Africa. Temperature and precipitation variability have been substantially stable over the past decades, with only a few areas showing significant changes against the background climate variability. The regions identified from the observations are remarkably similar to those defined from projections of global climate models under a “business‐as‐usual” scenario, indicating that climate change hotspots are robust and persistent over time. These results provide a useful background to develop global policy decisions on adaptation and mitigation priorities over near‐time horizons.

Intra-population trends in the maturation and reproduction of a temperate marine herbivore Girella elevata across latitudinal clines.

Latitudinal variation in the reproductive characteristics of a temperate marine herbivore, rock blackfish Girella elevata, was examined from three regions of the south-eastern Australian coast. Biological sampling covered 780 km of coastline, including the majority of the species distribution. The sampling range incorporated three distinct oceanographic regions of the East Australian Current, a poleward-flowing western boundary current of the Southern Pacific Gyre and climate-change hotspot. Girella elevata are a highly fecund, group synchronous (multiple batch)-spawner. Mean fork length (LF ) and age at maturity were greater for females than males within all regions, with both male and female G. elevata of the southern region maturing at a greater size and age than those from the central region. Estimates of batch fecundity (FB ) were greatest in the northern and southern regions, relative to the central region where growth rates were greatest. Significant positive relationships were observed between FB and LF , and FB and total fish mass. Gonado-somatic indices indicated latitudinal synchrony in spawning seasonality between G. elevata at higher latitudes, spawning in the late austral spring and summer. A late or prolonged spawning period is evident for G. elevata from the northern region. Juvenile recruitment to intertidal rock pools within the central and southern regions was synchronous with the spawning season, however, no juveniles were found within the northern region. The implications of latitudinal variation in reproductive characteristics are discussed in the context of climate and oceanographic conditions of south-east Australia.

Projected changes in heat wave characteristics in the eastern Mediterranean and the Middle East

According to observed twentieth century temperature trends and twenty-first century climate model projections, the region that encompasses the eastern Mediterranean and the Middle East (EMME) is identified as a climate change hot spot. We extend previous studies by a comprehensive climatology of heat waves in the EMME based on regional climate model simulations for the recent past and the end of the twenty-first century. A percentile-based definition of heat waves is used to account for local climatic conditions. Spatial patterns of several heat wave properties are assessed and associated with atmospheric circulation regimes over specific locations. To cover a range of possible future climates, we use three SRES emission scenarios. According to our results, all indices that characterize heat wave severity will strongly increase compared with the control period of 1961–1990. The northern part of the EMME could be exposed to increased heat wave amplitudes by 6–10 °C, and the southern part may experience 2–3 months more combined hot days and tropical nights. Heat wave peak temperatures will be higher due to the overall mean warming as well as stronger summer anticyclonic conditions. The projected changes will affect human health and the environment in multiple ways and call for impact studies to support the development of adaptation strategies.

Range extensions for heterobranch sea slugs (formerly opisthobranch) belonging to the families Diaphanidae, Plakobranchidae and Facelinidae on the eastern coast of Australia – CORRIGENDUM

Southern range extensions of the tropical Australian heterobranch sea slug fauna may be symptomatic of climate change, particularly in south-eastern Australia, a recognized climate change hot-spot. In the Solitary Islands Marine Park, northern New South Wales, the presence of biogeographic mixing means that the southern coastal distribution limit of several tropical marine species and the northern limit of some temperate species overlap. During a year-long series of monthly surveys of sea slug communities on intertidal rocky shores, we observed four species beyond their previously recorded range – Colpodaspis thompsoni, Elysia pusilla, Phidiana bourailli and Herviella claror. The southern migration of species is an anticipated response to warming seas and we note an apparent extension of the southern limit for these taxa.

Range extensions for heterobranch sea slugs (formerly opisthobranch) belonging to the families Diaphanidae, Plakobranchidae and Facelinidae on the eastern coast of Australia

Southern range extensions of the tropical Australian heterobranch sea slug fauna may be symptomatic of climate change, particularly in south-eastern Australia, a recognized climate change hot-spot. In the Solitary Islands Marine Park, northern New South Wales, the presence of biogeographic mixing means that the southern coastal distribution limit of several tropical marine species and the northern limit of some temperate species overlap. During a year-long series of monthly surveys of sea slug communities on intertidal rocky shores, we observed four species beyond their previously recorded range –Colpodaspis thompsoni, Elysia pusilla, Phidiana bourailliandHerviella claror. The southern migration of species is an anticipated response to warming seas and we note an apparent extension of the southern limit for these taxa.