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Conservation and Management Topics. Southwestern Willow Flycatcher ( Empidonax traillii extimus ): Conservation of a federally endangered bird. Subtly distinguished from other subspecies by lighter plumage and different wing and tail length ratios
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Conservation and Management Topics Southwestern Willow Flycatcher (Empidonax traillii extimus): Conservation of a federally endangered bird • Subtly distinguished from other subspecies by lighter plumage and different wing and tail length ratios • Breeding distribution distinct from other subspecies • 900-1000 pairs remain • Habitat degradation (loss of riparian areas) and fragmentation are primary causes of decline • Discussion Points: • Is it valuable to protect a subspecies? What information might inform your opinion? • How do we balance conflicting demands for water in the southwest? http://sbsc.wr.usgs.gov/cprs/research/projects/swwf/
Conservation and Management Topics Yellow-billed Magpie: How to study and monitor a species under threat • Species is entirely endemic to California • 2004-2005 high rate of death due to West Nile Virus • Comparatively little is known about population size and dynamics, making conservation status difficult to define • 2005 Yellow-billed Magpie Working Group highlighted dearth of information on basic population ecology of Yellow-billed Magpies (population size, population structure, rates of disease transmission and cause-specific mortality). Birds of North America • Discussion Points • If you were assigned the task of monitoring population health of the Yellow-billed Magpie, what would you study? Which questions should be prioritized?
Conservation and Management Topics Northern Pintail • Pintail populations declined through last part of 20th century • Decline largely attributed to loss of habitat in Canadian prairies due to agricultural conversion
Conservation and Management Topics Migratory connectivity of Bar-tailed Godwits • 2007 and 2008, satellite transmitters were attached to Bar-tailed Godwits in New Zealand and Australia • Birds were followed to their breeding grounds in western Alaska and Siberia • Study highlights the ability of birds to move across international boundaries, making conservation efforts challenging
Conservation and Management Topics The Notorious BHCO: Villain or Scapegoat? • Obligate nest parasite • Rapid range expansion over last 200 years, as a result of agricultural development and forest fragmentation • Lethal Cowbird control is a commonly used restoration and mitigation tool • While cowbirds have been documented to seriously impact at-risk species (e.g. Bell’s Vireo, Black-capped Vireo), substantial population-wide impacts of BHCO on other species has yet to be documented. • Discussion Topics • If you were a land manager, under what circumstances would you consider controlling cowbirds? • How would you fit cowbird trapping into a broader management plan? Source: Cowbirds and conservation http://www.audubon.org/bird/research/
Conservation and Management Topics California Gulls in South San Francisco Bay • South bay serves as nesting ground for many species, some endangered (American Avocets, Black-necked Stilts, Snowy Plover, California Least Terns, Calif. Clapper Rails) • California Gull breeding populations have increased 33x in 25 years. • California Gulls are significant nest predators; proposed salt pond restoration may increase CAGU pressure on other species by shifting breeding locations • Discussion Points • If you were to study this system, what questions would you ask? What type of study would you conduct? • Should California Gulls be controlled? Source: Ackerman et al. 2006 USGS
Conservation and Management Topics Barred Owl and Northern Spotted Owl: Native species in conflict
Conservation and Management Topics Barred Owl and Northern Spotted Owl: Native species in conflict • Northern Spotted Owl populations are declining due to forest fragmentation • Barred Owl distribution has spread across North America throughout 20th century, arriving in CA in 1981. • Barred Owl has been documented competitively excluding Spotted Owls • Barred/ Spotted hybrids have been documented Photos: Scott Jennings
Conservation and Management Topics Decline and Recovery of the Brown Pelican • Severe population declines through the mid-20th century largely attributed to DDT poisoning and DDT-induced eggshell thinning • Federally listed as endangered in 1970; CA listing in 1971 • DDT was banned by the EPA in 1972 • Brown Pelican populations began to recover • February 2009 CDFG commission voted to de-list the Brown Pelican • Significant threats still exist such as oil spills, entanglement with fishing equipment and disturbance to nesting grounds
Conservation and Management Topics Decline and Recovery of the Peregrine Falcon • Listed as endangered in 1970 (US); 1971 (CA) • Declines largely attributed to DDT-induced eggshell thinning • Extensive captive breeding and release program • By 1998 7000 Peregrines had been released; 700 established • Annual cost of recovery in 1990s= $5.4 million • In August 2009, CDFG commission voted to de-list the Peregrine
Conservation and Management Topics Saving a Species on the Brink: California Condor • Historic distribution extended across North America. Today, limited to California and Arizona • Population declines have been documented throughout the 20th century, likely multi-causal: • decreased food availability • Powerline strikes • Lead poisoning and poaching • other poisoning (often accidental) • In 1985-87, the last 9 wild California Condors were captured and put into a captive breeding program (totaling 27 condors). • By 1997, $20 million had been spent on CACO recovery efforts • By 2007, 298 CACO alive (144 in the wild), population still maintained by captive breeding • Ultimate goal of 450 Condors in three populations (one in California and Baja, one in Arizona, one in captivity. “So gentle a ghoul.” - William Dawson Sources: California Condor Conservation, Birds of North America