David Booth is Professor of Marine Ecology at University of Technology, Sydney, and Chair of the Scientific Advisory Committee, Sydney Institute of Marine Sciences.  He has published over 60 papers and book chapters on reef fish ecology, specialising in recruitment processes and the effects of environment, including climate change factors on dispersal and behaviour of coral reef fishes.

Department of Environmental Sciences, University of Technology Sydney. PO Box 123, Broadway NSW 2007, Australia. .(JavaScript must be enabled to view this email address)

Associate Professor Graham Edgar of the University of Tasmania/ Tasmanian Aquaculture and Fisheries Institute has a variety of research interests including developing an understanding of natural variability of reef-associated species (both spatially and temporally) and the processes responsible for this variability. A key component of the current research being understaken by the Marine Biodiversity Research Group relates to the extent that assemblages within MPA’s change following protection, and the reference role that MPA’s can provide for determining the extent of human impacts on the biodiversity of the remaining coastline.

Tasmanian Aquaculture and Fisheries Institute. Private Bag 49, Taroona. Hobart TAS 7053, Australia. .(JavaScript must be enabled to view this email address)

Ron is a marine ecologist with diverse interests, ranging from effects of climate on recruitment variability of inshore fish and crustaceans and management of invasive species to use of deep-sea corals as indicators of paleo-climate and oceanography.  He got his Ph.D. in fish behavior and ecology at the University of Miami, and did post-doctoral work at Scripps Institution of Oceanography and the University of Sydney, and joined CSIRO Marine and Atmospheric Research in 1983.  He was the foundation head of the CSIRO Centre for Research on Introduced Marine Pests (CRIMP) and since 1997, he has lead a project aimed at developing genetic technologies for controlling introduced pest species (with a particular emphasis on carp).  He has had a long interest in the use of the chemical composition of otoliths (“ear stones”) in fish as possible markers of their movements and ecology, and recently broadened that interest to include analysis of the similar composition of deep-sea corals as indicators of long-term changes in ocean conditions and its implications for both understanding climate variability, the biodiversity and ecology of marine organisms and the viability of deep-sea reef communities.

Climate Adaptation Flagship, CSIRO Marine and Atmospheric Research. GPO Box 1538, Hobart TAS 7001, Australia.  .(JavaScript must be enabled to view this email address)

Dr Rod Lenanton as Senior Principal Research Scientist for the Western Australian Fisheries Department, with more than 45 years experience in the field, is one of Western Australia’s most highly regarded finfish fisheries scientists. An Adjunct Professor of Murdoch University’s Division of Science and Engineering, Western Australia, Rod has spearheaded a number of groundbreaking projects in the management and habitats of economically important species, including how coastal finfish fisheries are affected by the Leeuwin Current. His latest research includes risk assessment and prioritisation of sustainable harvest level estimation of indicator species, the development of monitoring and assessment strategies within a broader Ecosystem Based Fishery Management (EBFM) framework, and the implementation of the Integrated Fisheries Management Initiative. In 2002, he was presented an Outstanding Service Award (nominated by peers), for service to the fishing sector in WA. Along with these notable achievements, he has mentored/supervised many young scientists and made a broad contribution to the subject’s body of scientific literature.

Department of Fisheries Western Australia. PO Box 20, North Beach WA 6920, Australia.  .(JavaScript must be enabled to view this email address)

Professor Michael Kingsford is Head of the School of Marine and Tropical Biology, JCU. The focus of his research is on fishes of all stages of life history; their population dynamics, where they live and the organisms they interact with in pelagic and reef environments. His major areas of research over the last 5 years can be divided into the following programs: biological oceanography (with special reference to presettlement fishes); pelagic ecology and fisheries with a focus on fish attraction devices (FADs) and large jellyfishes; population dynamics of reef fishes; interactions between reef fish and organisms associated with reefs; the use of microchemistry to elucidate the environmental conditions experienced by fishes (especially those related to pollution) and the connectivity of populations of fishes.

School of Marine and Tropical Biology, James Cook University. Townsville QLD 4811, Australia. Please direct all enquiries through Ms Rose-Marie Vasiljuk (PA.) .(JavaScript must be enabled to view this email address)

Greg is Statewide Leader of Marine and Estuarine Ecology for Primary Industries Research Victoria as well as Honorary Principal Fellow in the Faculty of Science at the University of Melbourne. He completed his BSc Honours at James Cook University in 1981 and my PhD at the University of Melbourne in 1986. His research has focussed primarily on juvenile ecology and the causes of recruitment variability in marine fish, specifically the relative roles of active and passive processes in the dispersal and settlement of larval fish, habitat relationships in fish recruitment (particularly with seagrass and habitat structure relative to location). Tools such as numerical hydrodynamic modelling (in collaboration with Dr Kerry Black), otolith daily ring analysis, and artificial seagrass habitats have been used extensively in this research. Current research interests have broadened into other areas of fish ecology, including the use of otolith microchemistry to examine fish stock structure and migration patterns, the use of stable isotopes to explore the plant basis of fish food chains, and the use of acoustic tags to track movements of fish.

Faculty of science, University of Melbourne. VIC 3010, Australia. PH: 03 52580333   .(JavaScript must be enabled to view this email address)

Dr Will Figueira is a senior lecturer in Marine Animal Biology with the University of Sydney. He obtained his BSc in 1993 (University of California) and PhD in Marine Ecology in 2003 from Duke University, USA. His research focuses on fish population ecology, specifically the behavior and demographics of individual populations including post- settlement demographics of reef fishes,  the large scale connectivity patterns, and potential for range shifts due to climate change. Interest in larger scale dynamics of reef fish has evolved into the development of conceptual and analytical models of applied metapopulation theory to marine systems in general, to study the impact of variations in habitat quality and network connectivity on system dynamics and specifically source-sink structure. This work can be used for citing marine reserves and creating effective, biologically interacting reserve networks.

Centre for Research on Ecological Impacts of Coastal Cities, School of Biological Sciences Marine Ecology Laboratories, A11. University of Sydney. NSW 2006, Australia. .(JavaScript must be enabled to view this email address) 

Climate change stressors can affect life histories of temperate marine fishes in a number of direct and indirect ways. Here we review evidence for climate change stressor impacts on the following aspects:  larval transport, larval connectivity, settlement and recruitment (early post-settlement survival and overwintering), growth rates, assemblage structure and range shifts, spawning and egg production (including nursery grounds). Consequences such as changes in fisheries catches, increases in populations of invasive species and indirect effects that are affected by climate-change stressors are detailed here.

Table 1. Fisheries production, gross value - 2005-06 From ABS Year Book Australia, 2008

Ocean currents
Climate change is predicted to enhance the strength, annual duration and southward extent of Boundary Currents (East Australian Current [EAC], Leeuwin Current) and associated eddies (Ridgeway 2007). The position of the Tasman front will shift southward (Ridgeway 2007). Although the EAC is offshore, it will affect coastal temperate fishes through changes to larval dispersal which can affect settlement to adult habitat. Larval connectivity longshore will be enhanced for species advecting using EAC waters (i.e., north to south) [this also applies to floating eggs]. For instance, Lenanton and others (Lenanton et al. 1991, Lenanton et al. in press) have considered the effects of the Leeuwin Current on recruitment strength (related to fisheries catch) of a range of species. Australian Salmon (Arripis trutta) recruitment strength was directly related to Leeuwin current flow, especially in the range-edge SA stock (Lenanton et al. 1991, Lenanton et al. in press). Leeuwin current was also shown to directly affect catchability in the south-coast fishery (Lenanton et al. 1991; Caputi et al. 1996). For Australian Pilchard, (Sardinops sagax) strength of the Leeuwin Current positively related to winter egg transport eastward and abundance of 2+ recruits in the Albany WA fishery, although this was masked by mass mortalities of adults in 1995, 1998/99 (Lenanton et al. 1991; Fletcher et al. 1994; Caputi et al. 1996). However, Leeuwin current strength was only weakly (r2= 0.29) related to Whitebait (Hyperlophus vittatus) recruitment, and not related at all to Dhufish (Glaucosoma hebraicum) or Tailor (Pomatomus saltatrix) recruitment (Gauhan et al. 1996; Caputi et al. 1996; Lenanton et al. in press).

Despite dispersal of tropical reef fish larvae into SE Australia clearly relating to general EAC strength (peak settlement January-April coinciding with maximum EAC flow), individual EAC incursions to the coast were generally unrelated to pulses in settlement, although several direct instances were noted (Booth et al. 2007).

Gaughan (2007) claimed that the Leeuwin Current system most likely contributes a net negative impact on success of shelf teleost eggs and larvae. Larvae of shelf teleosts entrained and trapped in the warm-core (WC) eddies that form from the Leeuwin Current and then propagate offshore, would contribute little to recruitment. Given that larval teleosts predominantly feed on copepods and that these were much less abundant in WC eddies than is typical of shelf waters, the general larval feeding conditions in the WC eddy were inferior to those on the shelf. Any larvae that escaped from the eddy, that were able to orientate towards the shelf and had sustained swimming capabilities, would incur significant energetic penalties when attempting to return to the shelf. Furthermore, flow of the Leeuwin Current onto the shelf could dilute the concentrations of phytoplankton and zooplankton, negatively impacting feeding conditions for larvae that remain on the shelf.

Ocean temperature
Sea surface temperatures (SST) have been shown to have risen ~2°C off Australia’s SE coast since 1925, with interannual variation in extremes also increasing (Figure 1: Figueira and Booth 2009). Similar changes are likely to have occurred in SW Australia via the Leeuwin current (e.g., Hutchins and Pierce 1994) although increases in SST off the West Coast is thought not to be related to a strengthening of the Leeuwin Current, with declines in the frequency of strong Leeuwin Currents over time. Rather, it is suggested that the more likely mechanism is air-sea heat flux into the southern Indian Ocean (Pearce and Feng, 2007; Caputi, de Lestang, Feng & A. Pearce (2009).

Since fishes (and their food) are ectotherms, key metabolic processes such as respiration, activity level, growth and reproductive development are linked to water temperature. Scope for larval dispersal has presumably increased for warm-water species, and possibly cold-water species, since swim speeds are increased, although this is possibly countered by shorter pelagic larval durations (O’Connor et al. 2007).

Jenkins and King (2006) showed that increased water temperature would cause an increase in larval growth, therefore contributing to larval survival of King George Whiting (Sillaginodes punctata), but may also indicate enhanced physical transport and/or plankton productivity. Overall, larval growth rate of King George whiting is a very strong predictor of postlarval abundance, which in turn will influence fishery recruitment in 3–5 years’ time.

Figure 1: Average winter (July – August) sea surface temperatures at five locations along the east coast of Australia since 1870 based on the HadISST1 global SST reconstruction. Dashed line is a smoothed (10 year window) average. Location abbreviations are as follows OTIS, One Tree Island; BYRN, Byron Bay; SOIS, Solitary Islands; LHIS, Lord Howe Island; PTST, Port Stephens; SYDN, Sydney; JRVS, Jervis Bay; BATE, Batemans Bay; MERB, Merimbula. (Figueira and Booth 2009)

Spawning is well known to be temperature-related in marine fishes including phenology (timing) of spawning events and hatching, egg production and hatch success (e.g., Ciannelli et al. 2007). Jenkins et al. (2000) showed that King George Whiting spawn in late autumn/winter. It is possible that increased SST could lead to contraction of spawning period and southward movement of the spawning area for this and other species. SST rise is expected to reduce growth rate, and spawning success of pink snapper (Pagrus auratus) at the northern extent of its distribution (oceanic waters off Shark Bay, WA), and may enhance spawning success at the southern extent of its distribution (WA south coast). Ultimately SST is expected to change distribution of stock and the magnitude of catches in both the northern and southern extent of pink snapper distribution in WA (Wakefield unpub. PhD thesis). Maximum size is lower at both the higher and lower extent of it’s distribution in WA. Further, the south coast population is not being subjected to the same degree of warming as the lower west coast (see Pearce & Feng, 2007). Indeed during the spring and summer of 2005, very low water temperatures effectively totally suppressed spawning. The preferred spawning/nursery habitats in temperate WA are protected nearshore embayment. So if elevated water temperatures do make these less suitable, the lack of alternative habitats further south could also be an important limiting factor.
Early post-recruitment survival will also be affected by SST rise. For a suite of tropical reef species that disperse down the SE Australian coast, an overwintering survival threshold of around 17.5°C has been demonstrated. This threshold was exceeded in 2001 and 2006 (warmest winters in 150 years: Figueira and Booth 2009; see Figure 2) leading to significantly greater numbers of several tropical species making it through the first winter at southern latitudes.

Figure 2:  Summary of relationship between the number of winter survivors of each species (a-h, one species per panel) at each location (normalized to the maximum number observed at that location) and the average winter (July – August) temperature at that location. Species are as listed for each plot and points are coded by location as given in (d). Dashed curves are best fit from significant (P

< 0.05) sigmoidal model fits as described in Figueira and Booth 2009a.

Figure 3: Comparison of surface (10 m) summer (January - March) mean temperatures at the Maria Island oceanographic station (black line) and historical variability in juvenile growth rates, pooled, for three shallow water fish species in south-east Australia (red line) (from Thresher et al. 2007).

Growth of fishes is generally temperature-dependent but typically shows a thermal maximum (Biro et al. 2008; Munday et al. 2008) which is shifted for tropical vs. temperate species. Therefore effects of temperature on growth performance cannot be generalised. As above, larval growth of King George whiting was positively related to SST (Jenkins and King 2006) which in turn was likely to be related to Leeuwin-current strength. Increased SST corresponded to higher recruitment, most likely related to higher larval growth/survival and/or increased transport, but local wind forcing in Bass Strait may also have contributed (Lenanton pers. comm.). Otolith (earstone) analyses showed faster growth of long-lived fish species in deeper waters (

<250m , e.g., orange roughy (Hoplostethus atlanticus), but slower growth for shallower species such as jackass morwong (Nemadactylus macropterus, Cheilodactylidae) and banded morwong (Cheilodactylus spectabilis, Cheilodactylidae: Thresher et al. 2007, Figure 3). In aquarium experiments in Sydney, elevated water temperatures had positive effects on escape response, feeding and growth of tropical vagrant reef fish (Abudefduf vaigiensis) but no effects on a confamilial local damselfish (Parma microlepis) probably because the latter was at its optimal temperatures regime (16 - 21°C) (Figueira et al. 2009).

Consequences of the above and other life-history responses to SST rise are predicted to include changes in local assemblage and range shifts of individual species (sensu Perry et al. 2005 for North Sea demersal species). As might be expected, a suite of warm-water species with dispersive larvae have been noticed in southern parts of Australia. For instance, 45 species, representing 27 families (about 30% of the inshore families in the region), exhibited major distributional shifts that are thought to be climate related, presumably due to SST rises in SE Australia (Last et al. 2009; see Table 2). In contrast, at a location with some of the best long-term SST records in Australia, the Maria Island reserve in Tasmania, Stuart-Smith et al. (2009) showed no significant changes in local fish assemblages over the last decade, indicating resilience to climate change. But they conclude “we suggest that our study encompassed a relatively stable period following more abrupt change, and that community responses to ocean warming may follow nonlinear, step-like trajectories.” Not usually considered are possible vertical range shifts of fishes in response to SST changes, which may affect thermal stratification of coastal oceans (e.g., Kingsford 2003, Annesse and Kingsford 2005)

Table 2: Numbers of families and species of fishes in each of the different classification categories based on the 37 families and 61 species with observed distributional and/or abundance changes in Tasmania (from Last et al. 2009).

Indirect effects of climate-change associated SST rise on temperate fishes have been significant, especially via changes in habitat. For example, Ling et al. (2009) found increased SST down the eastern seaboard was linked to range expansion of the (Centrostephanus rodgersii), a habitat-forming urchin that creates barren grounds that are preferred habitat for numerous temperate reef fishes such as Parma microlepis (Kingsford pers. comm.). Expanded urchin barrens are thus likely to facilitate community-level shifts amongst fishes, and these may already be occurring through direct SST rises. Glasby and Gibson (2007) demonstrated that the invasive brown alga Caulerpa taxifolia responded to warmer waters through dramatically higher growth rates and spreading capacity. Given avoidance by certain taxa (e.g., pipefishes: Syngnathidae York et al. 2005) for C. taxifolia, and its encroachment into and displacement of preferred seagrass beds, potential indirect effects of SST on this invasive habitat are likely to affect seagrass fish populations in estuaries. On the other hand, some cold-water invasives may be retracting southward. Lockett (2007) recorded diminished distribution of the invasive goby Tridentiger trigonocephalus in Sydney Harbour compared to cooler-water Port Phillip Bay. Laboratory experiments confirmed that water temperature was negatively related to reproductive development in this species. Seagrass, a significant fish nursery habitat (McNeill et al. 2006) can be vulnerable to higher temperatures (e.g., dieback: Seddon et al. 2000), while southern kelps are retracting southwards along SE coasts. Clearly major changes in key fish habitat are linked to SST rises (Millar pers.comm.).

Hobday et al. (2007) investigated climate impacts (particularly SST rises) on south-east demersal fisheries. The relatively long biological time-series already in existence and documented range changes suggest this is an area where clear impact will occur. The southeast area is also the region where climate models indicate rapid warming (Tasman Sea warming), and considerable social disruption would occur if key fisheries were affected.

El Niño-Southern Oscillation
ENSO-linked zonal westerly winds have been trending down (Jenkins 2005) which may be related to climate change while at the same time catches of King George Whiting (Sillaginodes punctata) have been increasing; zonal westerlies seem to be more related to variability in catches rather than the mean (which may depend more on SST or seagrass cover in nursery habitat). The ENSO abundance/catchability relationship is positive hence increasing El Niños under climate change would have a negative effect on catch (but not necessarily on abundance if catchability is an issue). Jenkins et al. (1997) showed that strong westerly winds and low barometric pressure associated with the passage of weather systems lead to positive sea level anomalies in Port Phillip Bay, and the passive transport of larvae into the bay.  Wind variability is also linked locally to fish catches (e.g., Tasmanian trumpeter: Thresher 2002), and interannual changes in the strength of zonal westerly winds are strongly linked to fishery catches in southeastern Tasmania

Sea-level rise
Sea-level rise is likely to have strong indirect effects on temperate fish production. Key estuarine habitats (mangroves, seagrass, saltmarsh) are all responding to climate-change induced sea-level rise. Mangrove stands are increasing in area at the expense of saltmarsh in SE Australia and key saltmarsh habitats are shrinking (Saintilan and Williams 2005). Saltmarsh is a nursery for crab zoea (larvae) production so in turn acts as a key food source for estuarine fishes (Mazumder et al. 2006). Sea-level rise due to climate change may impact coastal habitats important as breeding or nursery areas. Commercial species that use coastal habitats include pink snapper (Pagurus auratus), southern sea garfish (Hyporhamphus melanochir), Australian herring (Arripis georgianus), whiting and mullet (Fletcher and Head 2006).

Ocean acidification
No direct effects are yet noted for temperate marine fishes although pH effects on calcification of shells of prey (e.g., molluscs for sparids) may have an impact. There is also evidence that pH can affect chemical cueing (Munday et al. 2009) and thus larval behaviour during dispersal may be negatively affected at drops of as little as 0.3 pH points. Where cueing for orientation and settlement is impaired, recruitment may be reduced and overall realized connectivity patterns altered.

Estuarine freshwater inputs
Many fish species rely on freshwater inputs to estuaries, either directly (e.g., Gillanders and Kingsford 2002) or indirectly through stimulation of food source (e.g., prawn abundances respond to freshwater flushes:  e.g., Ruello 1973). Episodic freshwater flow events been shown to affect estuarine fish catches in eastern Australia (Gillson et al. 2007), with recent drought conditions correlated to reduced catches.

The black bream (Acanthopagrus butcheri) catch in Gippsland Lakes has declined markedly over the last decade, and this coincides with a “drought” over the same period, linked to climate change (Nicholson et al. 2005). Successful bream spawning requires intermediate salinities but these conditions have retreated out of the Lakes and up the feeder rivers. This means that the potential spawning area has decreased markedly. The results have significant implications in terms of climate change that is predicted to lead to warmer, drier conditions in south-eastern Australia, potentially increasing stratification and subsequent hypoxic zones and related egg mortality.

Sea surface salinity
A strong positive relationship between surface salinity and recruitment index of West Coast dhufish and tailor has been established (Lenanton et al. in press, Ayvazian et al. in prep.). The increased salinity arose through a combination of upwelled high-salinity water and the evaporation of warmer Leeuwin Current surface water. However, salinity probably represents a surrogate for other physical and/or biological factors that influence larval survival.

Key changes to the physical environment expected to occur for temperate marine fishes by 2030 will be slightly elevated SST, increased incidence of drought and reduced freshwater input to estuaries. Some possible consequences to key fish taxa are given in Table 3.

2030
Ecological consequences most likely to be observed by 2030 are:

Southward extent of tropical species/range shifts
A combination of climate change impacts lead to establishment of new fish species at southern latitudes e.g., WA coastal fishes may establish/increase abundance in SA waters. For some estuarine species, key spawning locations move upstream, the result of a combination of lower freshwater inputs/higher salinity and increased estuarine temperatures. Greater southward larval advection and increased growth rates occur due to warming SST, and alteration to upwelling and onshore winds. Changes to boundary current strength (East Australian Current and Leeuwin Current) and warming SST are likely to enhance settlement and early survival of warm-water species, with the opposite for southern species,.

Effects on larval dispersal and settlement
The East Australian Current future scenarios indicate a strengthening of flow (combination of southern extension, duration and volume), which will enhance southern advection of tropical and warm temperate pelagic larvae, possibly at the expense of more-southern, temperate species.

Impacts on species reliant on estuarine freshwater inputs and habitats
Rainfall in SE Australia is generally expected to reduce over the next 20 years with implication for fish populations in coastal regions. For example, the projected reduction in spring rainfall in Victoria would negatively impact on fish species that depend on freshwater input for spawning or egg survival such as black bream (Acanthopagrus butcheri: Nicholson et al. 2008). Reduction of seagrass habitat, which forms key nursery area for juveniles of certain species, is also expected.

2100
Key climate-changes effects by 2100 would be significant given projected SST rises of over 2°C and sea level inundations. These would include:

Range shifts and local extinctions
Establishment of previously-tropical species in southern waters (e.g., Figuiera and Booth 2009) while some southern species become locally extinct in Australian waters or globally extinct. The future behaviour of the boundary currents will play a large role in range shifts of coastal fish species.

Losses of key estuarine and coastal fish habitats
Large-scale loss of saltmarsh and seagrass beds, key estuarine fish habitats, coupled with loss of connectivity as the habitats become disjointed, will affect coastal fish species. However mangroves, also a key estuarine fish habitat, may expand further south due to warming temperatures and sea level rise, and replace salt marsh areas in certain regions. Increased estuarine salinity may lead to the possible local extinction of species such as black bream (Acanthopagrus butcheri) on east coast.

Major impacts on Fisheries
Coastal shifts in centres of distribution of key fish species and retreat of southern species is expected down SE and SW coasts with major negative impacts on NSW and mixed impacts on WA fisheries.

Table 3:  Predicted effects of expected climate-chance stressors on temperate fishes, by habitat/origin/behavioural types.

• North-south range shifts of temperate and tropical fish species due to warming sea surface temperature effects on species’ tolerances and ocean current changes linked to larval dispersal potential are occurring and will accelerate.

• These is some conflicting evidence of fish assemblage resilience in the face of climate-change, with a long-term study at Maria Island, Tasmania indicating little change over a decade. However, other reports suggesting numerous warmer-water species appearing recently off Tasmania.

• Range retractions of key commercial species like Black bream (Acanthopagrus butcheri), and other southern species are likely.

• Not all range changes will be in a latitudinal direction. For instance, species such as pilchards (Sardinops sagax) are showing East/West range shifts along the South Australian coast, and depth distributions may also shift.

• Complex interactions are and will occur between ENSO, winds, sea surface temperature, currents, and fish range shifts

• Sublethal effects of climate change will include effects of sea surface temperature on growth. The optimum latitude for growth will change but warmer waters are often inversely correlated with ocean productivity, hence fish food resources, so implications on fisheries productivity are unclear

• Strong interactive effects with changing habitat types, such as kelps, seagrasses, mangroves will be difficult to predict but likely to be at least as important as direct climate-change effects on temperate fishes.

• A strong potential exists for enhancement of warm-tolerant invasive taxa (e.g,, urchins) into southern coastal waters, with flow-on effects on fish assemblages

(a) Amount of Evidence
Sea Surface Temperature: MEDIUM evidence

There is good evidence of SST warming and some solid key evidence of effects on overwintering of tropical species and enhanced growth rates of some taxa but less conclusive with respect to assemblage shifts. Given the strong links fish physiology/production with temperature, we would expect SST links to fish biology to be strong.

Ocean currents (East Australian Current, Leeuwin Current): MEDIUM evidence

There are apparent effects on the advection of species further south and limited evidence of shifts in key fisheries zones along southern coast (e.g. pilchards).

ENSO/Zonal westerlies: MEDIUM evidence

Sea level rise: MEDIUM evidence

There is good evidence that sea-level rise has caused limited coastal zone inundation and good evidence for expansion of mangrove habitats and loss of saltmarsh as a result of sea-level rise.
Ocean Acidification: There is NO direct evidence as yet

Estuarine freshwater inputs: LOW-MEDIUM evidence
There is medium evidence that ENSO/climate change have led to drought conditions and lower freshwater input to estuaries; and low-medium evidence that reduced freshwater input to estuaries affects (negatively) fish production (spawning, catch rates, but no evidence for effects on diadromous fish passage).

Extreme weather frequency: There is NO direct evidence as yet

(b) Degree of Consensus
There is GOOD consensus that sea surface temperature warming are affecting ranges, growth of temperate marine fishes and LOW consensus that ocean current changes (East Australian Current and Leeuwin Current strengthening) have occurred with consequent tropical fish larval dispersal and juvenile persistence southward; POOR consensus on other stressor effects such as sea-level rise (lack of data).

Multiple Stressors
Climate change impacts and also adaptive responses will depend on interactions with other key stressors. Overfishing for example has affected some taxa in southern Australia, through direct effects on overall abundance, size-selective removals (especially important for sex-changing species) and general habitat degradation (especially with trawling). In coastal areas, a range of human disturbance activities (e.g., riverbank disturbance increasing sedimentation and acid sulphate soils, estuary dredging effects on fish nurseries) can exacerbate any negative climate-change effects on fishes. On the other hand, establishment of a series of Marine Protected Areas around Australia over particularly the last decade has reduced the rate of change of human disturbances (particularly fishing, but indirectly activities such as land clearing, pollution in estuaries/catchments etc.)