Recovery of the Common Murre (Uria aalge) in Central California

Gerard J. McChesney*, Harry R. Carter, Michael W. Parker, Richard T. Golightly, Phillip J. Capitolo, Lisa E. Eigner, Sandra J. Rhoades, and Stephen W. Kress ACKNOWLEDGMENTS

 Apex Houston Trustee Council  Command Trustee Council  Luckenbach Trustee Council  California Department of Fish and Game  NOAA - Gulf of the Farallones National Marine Sanctuary  Point Reyes National Seashore  California Coastal National Monument  U.S. Geological Survey - WERC Common Murre

 Marine, diving birds: feed on small fish, krill, squid;

 Colonial;

 Population in CA has changed dramatically since 19th century.

South Farallon Islands First Decline: 1848-1959

Common Murre population size, South Farallon Islands, 1850-1959. Data from Ainley & Lewis (1974), Carter et al. (2001). 1960-1982: Partial Recovery

. In 1969, the South Farallon Islands were protected in the Farallon National Wildlife Refuge. . Murre colony on Farallones increased to 103,000 breeding birds by 1982. . Central California population estimated 200,000 breeding birds in 1979-1982.

1983-1995: Second decline

Common Murres caught in a gill net. Oiled Common Murre on a California beach. DEVIL’S SLIDE ROCK

. Between 1982-1986, a colony of nearly 3,000 murres was extirpated. 1996-2010: Path to recovery

 In 1996, murre colony restoration began with settlement funds from the Apex Houston oil spill.

 Set gill net fishery in central California discontinued – murre mortality reduced.

 Productive ocean and foraging conditions.

 Murre population responded with increases. COMMON MURRE RESTORATION DEVIL’S SLIDE ROCK

600 Territorial sites 500 Breeding sites 117 400 86

300

51 200 84 394 361 88 45 43 23 100 190 9 10 16 164 113 123 110 5 9 13 100 6 70 0 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007

“Social attraction” restoration plot. Murre Population Trends: 1979-2006 Central California Common Murre Population

Current Population Colony Estimate (No. Breeding Birds) Point Reyes 60,000 Point Resistance 7,500 Millers Point Rocks 100 Double Point Rocks 15,000 Bird Island 50 Devil’s Slide Rk & Mainland 850 North Farallon Islands 100,000 South Farallon Islands 200,000 Castle-Hurricane 5,500 TOTAL 374,000 Threats to Continued Recovery

. Human disturbance . Disturbance or predation from pelicans, ravens . Oil spills . Climate change

. Oil spill settlement funds are now used for efforts to reduce human disturbance.

Summary

. Common Murres have undergone dramatic population changes since the mid-19th century, mainly due to human- caused factors.

. Numbers recently have recovered to highest levels since the early 20th century.

. Threats such as future oil spills, human disturbance, avian disturbance and predation, and climate change could hinder continued recovery.