Summary of Climate Change Research  PRBO's four decades of research on bird populations and ecosystems provide us with a unique look at the effects of climate change on birds and their ecosystems.   New Publication by PRBO Biologists in The Auk: Climate Models and Ornithology Listen to NPR podcast  on climate change signals on the Farallones.
Click on an ecosystem below to view a summary of PRBO's research
Terrestrial Ecosystems	Wetland Ecosystems	Marine Ecosystems

Terrestrial Ecology Climate Research at PRBO Linking weather to bird populations Rainfall amount and timing and temperature changes influence bird populations.   A Rainfall Example:  Song Sparrows in Coastal Scrub: The graph below shows how more rain means more young song sparrows survive to leave the nest.  This is from our studies of Song Sparrows in coastal scrub at our Palomarin Field Station, central CA.  Publication: Chase et.al. 2005.    A Temperature Example: Songbird Migration Timing Shift Warmer temperature can alter the timing of bird migration. Our bird banding station at the Palomarin Field Station (Marin County), shows that songbird arrival dates are changing, some birds arrive earlier in spring, while some birds are arriving later. Wilson's Warblers are arriving earlier as temperature warms.   This change in timing could impact a species’ ability to succesfully reproduce and find food. With the onset of climate change, adapting to variable rainfall and temperature changes could pose a threat to many bird species.  PRBO biologists aim to understand these relationships, predict future changes, and inform land and resource management in order to conserve ecosystem integrity.   Global Climate and Altered Migration Timing Our studies have also shown relationships between global climate cycles, such as Northern and Southern Oscillation Indices and Pacific Decadal Oscillation, and phenology.  PRBO biologists and partners have found that the arrival timing of 10 bird species were associated with both temperature and a large-scale climate oscillation index (El Niño Southern Oscillation, ENSO; North Atlantic Oscillation, NAO; and/or Pacific Decadal Oscillation, PDO). An additional study of fall phenology involving multiple sites in California found widespread evidence of earlier fall phenology – likely from earlier breeding – consistent with research detecting both earlier western North American spring and advanced spring migration on the Pacific coast (MacMynowski et al. in review).  Current Research: Predicting impacts of climate change in the Central Valley PRBO biogists studying terrestrial ecosystems are examining long term climate patterns and projecting the effects of climate change on bird populations in the Central Valley of California. Biologists are creating statistical models that show current distributions of birds in California and predicting how distributions might change in the future under different climate change scenarios. Click [here] to view an annotated bibliography of PRBO related terrestrial ecosytem studies.   Some of PRBO's Terrestrial Ecologists [top]

Wetlands Ecology Climate Research at PRBO

SF Bay Wetlands
Our overall goal is to guide conservation planning for SF Bay wetland habitats in the context of rapidly changing climate conditions.

Wetlands provide vital habitat for wildlife and important ecosystem services such as flood control, water filtration, and carbon sequestration.

Climate change impacts SF Bay wetlands by:
rising sea level, resulting in marshes and mudflats being submerged
shifting salinity, resulting from increased salt water entering estuaries


Sea level rise and corresponding salinity shifts will alter and reduce wetlands in SF Bay. Which causes us to ask the question: "Will there be enough wetland habitat and the right kind of wetland habitat for birds and people?"

To answer this question, PRBO is:

• modelling and mapping wetland plant and bird species under various sea level rise scenarios,
• identifying habitats and species most in need of protection, and
• communicating these needs to management agencies to inform land acquisition and habitat restoration plans.

Coastal Strand Beaches and Dunes
Our overall goal is to inform the conservation and management of CA coastal beaches and dunes given the threat of sea level rise.

Climate change impacts beach and dune ecosystems by:
rising sea level, resulting in changes in beach erosion and accumulation of sand
increased storm intensity and frequency, resulting in erosion of coastal beaches

Changes in erosion and sediment accumulation may result in management activities such as beach armoring to protect urban areas.  How will these changes affect shorebird and waterbird populations using these ecosystems?

To answer this question, PRBO is:

• modelling and mapping wave transformation data and sea level rise to predict the impact to beaches and dunes,
• identifying habitats and species most in need of protection, and
• communicating these needs to management agencies to inform management and habitat restoration plans.

For more information on these wetland projects, contact Diana Stralberg at dstralberg at prbo dot org.

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Marine Ecology Climate Research at PRBO

Seabirds, marine mammals, fish, and even tiny invertebrates can teach us about how climate change affects our oceans and the animals living in it.

Understanding how climate change affects the ocean ecosystem is no easy task.  The ocean is diverse and complex.  Birds, marine mammals, and their prey are affected by ocean conditions influenced by climate, such as upwelling, sea surface temperature and El Niño/La Niña events.

Below is a summary of how climate affects the predators and prey of the Marine Ecosystem.  Topics covered include how climate impacts:

• Prey
• Reproduction and Survival
• Distribution and Abundance
• Sex ratios in a population
  

Climate Impacts Prey:

Marine predators feed on krill, fish, or squid. Upwelling and sea surface temperature influence the availability, amount, and location of prey. When birds and marine mammals can't find enough prey, their ability to survive and reproduce is affected.

What we have learned:

Climate Impacts Reproduction and Survival: 
Seabirds and marine mammal reproduction and survival is affected by climate change through changes in: 

• timing of breeding,
• reproductive success,
• survival, and
• distribution/abundance. 

Timing of Breeding:
Seabirds do best when their breeding is aligned with plenty of food in the ocean.  As outlined above, good upwelling and low sea surface temperature are needed to have plenty of prey (krill and fish and squid) in the ocean.

What we have learned:  Listen to NPR story on climate impacts to Cassin's Auklets

• Studies off central California have shown that seabirds can sometimes modify their timing of breeding:
  Publications:  Abraham & Sydeman 2004, Roth et al. 2005, Wolf et al. 2008, Roth et al. in prep 
• But not always, and when they can’t, they may not reproduce, may reproduce less, or have diminished nestling growth. 
• Cassin’s Auklet Nest Failure, 2005 and 2006
  Failure to reproduce was documented at the Farallon National Wildlife Refuge in 2005 and 2006 for the entire colony of Cassin’s Auklets, a krill-eating seabird.  This was due to decreased krill abundance in the ocean causing late timing of nesting and reduced breeding success.  At the same time, Common Murres, which feed on fish, weren’t as profoundly affected. Publications: Jahncke et al. 2008

Productivity
Productivity is a measure of the ability of a population of animals to successfully reproduce.  High productivity is needed to sustain populations.  Productivity is linked to food, timing of nesting and nestling growth and development, which can all be impacted by a changing climate, as outlined above.

What we have learned:

• Warm-water years (associated with reduced upwelling) generally result in reduced seabird productivity.
  
  This was shown in research conducted in the Gulf of the Farallones National Marine Sanctuary. Publications: Ainley et al. 1995, Abraham & Sydeman 2004, Jahncke et al. 2008, Roth et al. in prep 
• Larger oceanic processes such as the Pacific Decadal Oscillation (PDO) have been shown to influence seabird productivity. Our studies found that when the PDO was in a negative phase high breeding success occurred for murres on Southeast Farallon Island and low breeding success was seen during positive phases. Roth et al. in prep
• Nest Abandonment
  On the Farallon Islands, PRBO researchers observed unprecedented breeding failure of Cassin’s Auklets. In 2005 and 2006, changing climate patterns delayed spring  upwelling, which normally brings nutrients to the food web and supplies food (e.g. krill) to Cassin’s Auklets. Without the upwelling, the auklets didn’t have enough food to raise their young, and thus abandoned their nests. 

Some of PRBO's Marine Ecologists 

 [back to marine topics]