Table 1. Case study descriptions: system characteristics, external drivers, and observed climate change impacts.

Case
Study
Key System Characteristics Main Climate Stressors/Drivers Main Nonclimate Stressors/Drivers Observed Climate Change Impacts
Marine species range expansion Marine species’ range boundaries are often determined in part by habitat characteristics, both physical, e.g., temperature, substrate, and biological, e.g., competition, predation Increasing sea surface temperatures (SSTs) via strengthening of the East Australian Current (EAC), aiding larval transport and bringing tropical water further south leading to changes in productivity Habitat destruction from growth of coastal population and poorly planned coastal development, destructive fishing practices, shipping accidents, and boat anchorages Strengthening of the EAC (20% since 1960), causing changes in physical, chemical, and biological properties of temperate waters (Malcolm et al. 2011). Southward EAC extension has caused silicate concentrations to decline off eastern Tasmania (Thompson et al. 2009)
 
Changes in one or more of these range boundary determinants may cause a species range edge to shift Nonclimate-related changes in oceanographic conditions
Climate change is likely to lead to changes in one or more of these determinants for some marine species Fishing-mediated changes in competitor and predator assemblages Over 2.0°C increase in SST (east coast Tasmania 1944-2005) and declines in precipitation via a long-term drying trend have led to increasing salinity and therefore changes in productivity (declines of 8% per year in chlorophyll a concentrations, 1944-2005; Thompson et al. 2009)
The evidence is mounting that such range shifts are occurring as a result, either directly or indirectly, of climate change
 
Southern rock lobster (Jasus edwardsii) industry One of Tasmania’s most valuable resources, with the industry worth over A$65 m 2011-12 (but below the 2005-06 peak) Temperature increases have contributed to a decline in larval lobster settlement in eastern Tasmania over the last 15 years Increasing numbers of urchins (Centrostephanus rodgersii) invading from warmer New South Wales (NSW) waters assisted by EAC extension Change/decline in stock abundance particularly in northern parts of Tasmania (mainly last 5 years)
Dependent on rocky reef/macroalgal (kelp) habitat along the coastline Southward extension of the warm EAC (350km since 1960s) Kelp beds (rock lobster habitat) contracting due to urchin grazing Relative geographic redistribution of fishing effort (declined by 50% in northern waters and doubled in cooler southern waters, 1970-2009; Pecl et al. 2009)
Declining state-wide stock abundance (mainly last 5 years) Increasing octopus (Octopus tetricus) sightings, a likely predator of rock lobster (www.redmap.org.au) Interaction between increasing fishing pressure on high value red lobsters (Green et al. 2010), opportunities for rock lobster translocation, and climate driven temperature increases.
Product value differentiation (higher value red lobster caught in north – lower value paler lobster caught in colder southern waters) Increasing sightings of NSW rock lobster species (Sagmariasus verreauxi; www.redmap.org.au) Urchin barrens now cover 50% of some northeast Tasmania rocky reefs since arriving in the late 1970s
Reducing fisher participation since Individual Transferable Quota (ITQ) introduction (efficiency gains); around 312 licenses but 200 commercial fishers Changing fishery demographic (fewer young fishers entering because of alternative higher-earning opportunities elsewhere) Increasing octopus catch and octopus predation of lobster in pots
Increasing investor ITQ ownership Changing quota ownership characteristics are increasing variable fishing cost for lease quota fishers Reduced Total Allowable Commercial Catch (TACC; 1523 tonnes in 2008/09 to 1193 tonnes for 2012/13). Actual catch declined from 2200 to 1500 tonnes, between 1985 and 2008 (Linnane et al. 2010)
Aging fisher demographic Increasing fishing costs due to greater search time and farther travel
 
Oyster aquaculture The value of the Australian oyster industry is estimated around A$120 m in 2011. Warming SSTs; air temperature; zonal wind change; extreme rainfall events; sea-level rise limiting use of/access to land bases Land use in catchments affecting runoff and water quality Increased flood frequency in northern NSW is causing acidification of estuarine waters and resulting in higher estuary closure rates, i.e., farmers are unable to sell their stock more often (Dove and Sammut 2007)
Distributed aquaculture sector spread across bays and estuaries of NSW, South Australia, and Tasmania Disease outbreaks, which may be linked to climate drivers, such as herpes viruses and vibrios in Pacific oysters (Crassostrea gigas; POs), and the complex and fatal pathological conditions known as QX and winter mortality in Sydney rock oysters (Saccostrea glomerata; SROs).
POs and SROs are main species Likely to be most substantial in estuarine regions where rainfall changes can exacerbate pre-existing stressors associated with upstream management and development Increasing water temperature in northern NSW has been linked to increased risk and outbreaks of QX; aquaculture here has not recovered from QX outbreaks in the 1970s (Nell 2007)
Numerous disease threats to both species Issues relating to social license affect the legitimacy of the sector and thus the levels of political support
Numerous land use and surface runoff risks in estuarine systems Likely to be caused by complex synergistic interactions between multiple climatic and other drivers rather than a single cause
Mostly small, family-run businesses Energy costs of transport and cooling, related to distance to markets
Access to water based on leasehold; arrangements vary slightly between states
 
Great Barrier Reef marine tourism Reef tourism contributed around A$5.1 billion to the Australian economy in 2006 Reef based tourism is vulnerable to climate change impacts: sea level rise, increased water and air temperatures, increased storm/cyclone frequency and severity, ocean acidification, increased windspeed, changed rainfall and runoff, cloud cover affecting visibility, and changes in El Niño Southern Oscillation (Coghlan and Prideaux 2009, Wilson and Turton 2010). Substantial falls in visitor numbers are expected if environmental conditions, e.g., water quality, are degraded (De’ath and Fabricius 2008) with significant implications for regional annual income (Huybers and Bennett 2000). Sea and air temperatures are increasing; there is observed sea level rise, ocean acidification and more intense storms and more frequent rainfall (Poloczanska et al. 2012)
Diversity of small-medium businesses (retail, accommodation, and tour based)
Resilient to change (Fenton et al. 2007)
Spatially differentiated operations across inner and outer coral reefs and islands Global economic activity and other factors influencing businesses’ profitability Coral bleaching events on nearshore reefs have increased in frequency and severity since 1990 (Thompson and Dolman 2010)
Marine tourism activities and operations are diverse, encompassing live-aboard vessels, cruise ship operators, catamaran and kayaking tours, fishing, and diving. Existence of alternative reef destinations and competition with and economic viability of other iconic tourist attractions, such as North Queensland’s Wet Tropics
Reef bleaching influences the number of visitors (Oxford Economics 2009). Long lived corals are calcifying 15% less than prior to 1990 (Hoegh-Guldberg et al. 2007, De’ath et al. 2009).
Contributes to a growing hospitality industry of resort-style accommodations and restaurant services. Recreational and tourism services are strongly related to coral reef biodiversity, coral cover, and water clarity (Wielgus et al. 2004). Rapid coastal population growth (Great Barrier Reef Marine Park Authority 2009).