marine climate change impacts & adaptation report … · marine climate change impacts &...
TRANSCRIPT
The Centre for Australian Weather and Climate Research A partnership between CSIRO and the Bureau of Meteorology
Marine Climate Change Impacts & Adaptation Report Card: Seabirds
Dr Lynda E. Chambers1
B. Congdon2, N. Dunlop3, P. Dann4, C. Devney2
www.cawcr.gov.au
1 Centre for Australian Climate and Weather Research 2 James Cook University 3 Conservation Council (WA) 4 Phillip Island Nature Park
N Valez
The Centre for Australian Weather and Climate Research A partnership between CSIRO and the Bureau of Meteorology
Marine Climate Change and Adaptation Report Card for Australia
Assessment of state of knowledge of known and expected impacts of climate variability and change on Australian seabirds; Knowledge gaps; Adaptation options
Published November 2009
Sections:
Marine Climate
Temperature, Sea Level, EAC, Leeuwin
Current, ENSO, Ocean Acidification
Impacts on Marine Biodiversity
Tidal Wetlands, Seagrass,
Macroalgae, Phytoplankton
Zooplankton, Coral Reefs
Tropical Fish, Temperate Fish
Pelagic Fish, Marine Reptiles
Seabirds
The Centre for Australian Weather and Climate Research A partnership between CSIRO and the Bureau of Meteorology
Seabirds
• Consume significant amounts of marine resources
• Important role in marine ecosystems • Nutrient transfer from pelagic and offshore regions to islands, reef and coasts • Seed dispersal
• Movement of organic matter through soil layers (esp. burrow nesters)
• Upper trophic level predators
• Demography and reproduction often related to changes in trophic and oceanographic conditions
Photo: LE Chambers
The Centre for Australian Weather and Climate Research A partnership between CSIRO and the Bureau of Meteorology
Seabirds in the Australian Region
• ~110 species (including external territories) from 12 families
• 69% breed in region
• Many environmental and anthropogenic threats, including climate change
The Centre for Australian Weather and Climate Research A partnership between CSIRO and the Bureau of Meteorology
Climate and Seabirds
• Variation and changes in marine environment affect seabirds, influencing • Prey density • Seabird abundance • Distribution • Productivity • Behaviour
• Particularly true in regions of upwelling & boundary currents • Any change in availability of prey items has flow on effects to seabird abundance,
distribution, migration patterns and community structure at higher trophic levels
The Centre for Australian Weather and Climate Research A partnership between CSIRO and the Bureau of Meteorology
Impacts: Sea Surface Temperature
Observed: • Southward expansion of tropical seabirds (WA); • Later breeding in ENSO years (WA) & in cooler years (Little Penguins, Vic) • Reduced breeding participation and success in ENSO years (WA) and warm SST
years (GBR) • Increased survival of first year L. Penguins (Vic) in warmer years & decreased adult
survival
Expect: southward expansion or shifts, altered reproductive success & timing, foraging areas & possibly prey species
SSTs & laying date in Little Penguins
The Centre for Australian Weather and Climate Research A partnership between CSIRO and the Bureau of Meteorology
Increased land temperatures can increase heat stress and mortality, leading to reduced
breeding success (esp. surface dwelling birds)
Many seabirds (e.g. LP) unable to withstand prolonged exposure to surface air temperatures > 35 ºC, which lead to dangerously high body temperatures and heat stress
Impacts: Air Temperature
The Centre for Australian Weather and Climate Research A partnership between CSIRO and the Bureau of Meteorology
Alterations in currents, mixed layer depth & ocean stratification have potential to impact seabird
distributions, migration and foraging through impacts on supply of nutrients and light and, therefore,
prey species and subsurface predators that force and maintain prey at the surface
• Negative relationship between number breeding Sooty Terns (GBR) and precursor changes in
depth of 20 ºC thermocline
• Foraging and breeding success in Little Penguins linked to ocean stratification (prey more
dispersed in poorly stratified waters)
Impacts: Ocean currents, mixed layer depth, ocean stratification
The Centre for Australian Weather and Climate Research A partnership between CSIRO and the Bureau of Meteorology
• Strong winds and cyclones reduce breeding success, foraging and nesting habitats in northern Australia
• Cyclones can cause catastrophic damage of breeding colonies and deaths of individuals • Indirect effects include: wave inundation, erosion, storm tides and intensified currents
• Cyclonic activity can affect timing of breeding (e.g. Sooty Tern – GBR)
A composite weather satellite image from MTSAT-1R, 19 March 2006, 4.15pm (eastern standard time), showing Tropical Cyclone Larry over the Queensland coast, near Cairns and Innisfail. Image processed by the Bureau of Meteorology.
Copyright Commonwealth of Australia and Japan Meteorological Agency, 2006
Impacts: Winds, storms and cyclones
The Centre for Australian Weather and Climate Research A partnership between CSIRO and the Bureau of Meteorology
• Non-cyclonic storms and strong winds influence breeding success by reducing foraging success, increasing juvenile mortality and flooding nests (e.g. Roseate Terns)
• Storms associated with mass mortality of seabirds along Victorian coast
• Strong westerly winds (Jan-Mar) & later breeding in LP (Vic)
Impacts: Winds, storms and cyclones
Angela Wylie
The Centre for Australian Weather and Climate Research A partnership between CSIRO and the Bureau of Meteorology
Precipitation, floods and terrestrial runoff
• Few direct effects on survival or breeding success • Occasional heavy rain may flood burrows • Indirect (potential effects) include: impact on prey availability, quality of breeding habitat, fire risk • Anchovy productivity (important prey of LP) associated with streamflow in coastal areas
Sea level rise • No known quantitative links between observed SLR & changes in the distribution & abundance
of seabirds – future impact will vary with breeding habitat (Torres Strait, GBR)
Ocean Acidification • No known direct or indirect effects
The Centre for Australian Weather and Climate Research A partnership between CSIRO and the Bureau of Meteorology
Other extreme events (including fire)
• Prolonged periods of hot dry conditions increase risk of fire, including power-pole fires
• Synchronised breeding in seabirds increase vulnerability, esp. burrow nesting species
• Little Penguin maladapted fire response
The Centre for Australian Weather and Climate Research A partnership between CSIRO and the Bureau of Meteorology
Future changes
• Many uncertainties • Rising SST projected to decrease prey availability to many seabirds at current breeding
sites • Background rises in SSTs may foster persistence of tropical seabirds at more southern
latitudes • Potential for seabirds to shift breeding locations as result of inundation and/or degradation
of breeding sites is unclear & highly dependent on resilience of coral reef ecosystems and other breeding locations to CC
• Any increase in fire risk potential to severely impact some colony nesting seabirds • Increased surface temperatures likely to increase heat stress related mortality
The Centre for Australian Weather and Climate Research A partnership between CSIRO and the Bureau of Meteorology
Knowledge gaps
• Understanding drivers of change in seabird populations, including relative role of natural variability and CC
• Understanding factors determining resilience and adaptive capacity of marine ecosystems. E.g. How do seabirds respond to climatic changes: gradual vs trigger vs thresholds
• Knowledge of existing non-climatic threats and how these will interact with CC
• Which species and systems are more vulnerable? When can we make generalisations?
• Information on seabird movement and diet
• What is manageable, what are we managing for, and minimum amount of information needed for managers to differentiate particular actions
• Economic and social impacts of climate-related changes to seabirds? • Limits to current modelling of CC impacts on marine systems
The Centre for Australian Weather and Climate Research A partnership between CSIRO and the Bureau of Meteorology
Adaptation Responses
Many aspects of climate’s impacts on seabirds little known, vary by location and species, suggesting regional or colony by colony assessments of resilience or adaptive capacity may be required.
However, general principles:
• Reduce existing (non-climate) threats to increase resilience and chance of autonomous adaptation, e.g.
• Marine protected areas • Exclusionary fences limiting tourist access to colonies
• Feral/pest animal control
• Buffering potential negative effects of CC through habitat management
The Centre for Australian Weather and Climate Research A partnership between CSIRO and the Bureau of Meteorology
Adaptation Responses
• Monitoring and research – to improve adaptation responses
• Ex situ conservation or translocation
• Other species and site specific options
• Nest shading
• Signage at colonies
• Powerlines underground • Decoys to encourage new colonies
The Centre for Australian Weather and Climate Research A partnership between CSIRO and the Bureau of Meteorology
Conclusions
• Changes in oceanographic and climatic processes are impacting on Australian seabirds, across many foraging guilds
• Changes in distribution, success & timing of breeding, chick growth and survival of adult & immature birds
• Some uncertainty in future impacts • Southward expansion limited by available habitat & distribution of prey species
• SLR likely to reduce existing breeding habitat
The Centre for Australian Weather and Climate Research A partnership between CSIRO and the Bureau of Meteorology
• For many seabirds & regions we have limited information on prey distributions, foraging & movement patterns & ability of species to alter prey species or life-cycle timing
• Further research & monitoring of key species required
• Determine which species and systems more vulnerable to CC • Where generalisations about impacts & adaptation can be made • Which species are most effective indicators of climate impacts on higher trophic predators
Conclusions
The Centre for Australian Weather and Climate Research A partnership between CSIRO and the Bureau of Meteorology
Dr Lynda Chambers
Email: [email protected] Web: www.cawcr.gov.au
Thank you www.cawcr.gov.au