conservation of migratory birds -- 1970s amateur birders noticed decline in migratory songbirds, not...
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Conservation of Migratory Birds
-- 1970s amateur birders noticed decline in migratory songbirds, not as many seen in favorite birding spots over many years
-- small woodlots, urban areas in particular showed this
-- e.g., Rock Creek Park, Washington D.C., birders with notes since 1940s indicated about one third less by 1970s butpark size did not change to account for this decline
-- quantifiable data later included Breeding Bird Survey started in 1965with 1500 transects on roads throughout the U.S. and Canada
-- period from 1966 – 1987 verified dramatic declines in many species,75% of forest-dwelling and long-distance migrants especiallyhad declined
http://www.mbr-pwrc.usgs.gov/bbs/bbs.html
Radar studies in Gulf of Mexico also showedserious declines in migratory songbirds
Work by Sidny Gauthreauxusing images in 1960scompared to those takenin 1980s
Migratory waves had declined by 50%
Causes for declines:
-- forest fragmentation, declines steepest in long-distancemigrants that live in forests
-- have shorter breeding season, fewer eggs compared toshort-distance migrants
-- also predators, nest parasites involved in declines,e.g., raccoons, jays, crows, cowbirds
-- tropical deforestation also destroys winter habitat whenbirds are more densely concentrated in flocks
-- source/sink areas now used in conservation
Extinct (EX) - No individuals remaining. Extinct in the Wild (EW) - Known only to survive in captivity, or as a naturalized
population outside its historic range. Critically Endangered (CR) - Extremely high risk of extinction in the wild. Endangered (EN) - High risk of extinction in the wild. Vulnerable (VU) - High risk of endangerment in the wild. Near Threatened (NT) - Likely to become endangered in the near future. Least Concern (LC) - Lowest risk. Does not qualify for a more at risk category.
Widespread and abundant taxa are included in this category. Data Deficient (DD) - Not enough data to make an assessment of its risk of
extinction. Not Evaluated (NE) - Has not yet been evaluated against the criteria.[6]
IUCN Red Data Books started in 1963
-- thousands of plant and animal species evaluated everyfive years and categorized:
Endangered Species Act 1973
-- two categories for species as endangered or threatened
-- listed species receive immediate protection
-- also have Species of Concern, but these have no statusfor protection
-- Act also protects hybridization, recognizing it as part ofthe speciation process
California Gnatcatcher
ESA Case Examples
Dusky Seaside Sparrow
California Gnatcatcher
ESA Case Examples
Dusky Seaside Sparrow
Whooping Crane
Solutions:
-- protect habitat, especially sources or larger forests
-- Partners in Flight, cooperation between 12+ Federalagencies to locate and protect most importantsites
-- also international cooperation needed, training, andeducation
-- monitoring of populations to track changes, managespecies and habitats
San Pedro River valley, Arizona -- BLM protected 40 mile section in 1989 -- growing populations of songbirds
Western HemisphereShorebird Reserve Network (WHSRN)
Started by private groupsin 1985
Locates and protectsimportant stopover areas
Periodic synchronouscounts to monitorpopulations
Ivory-billed Woodpecker
11 Feb. 2004: first sighting in Big Woods, AR21 May 2005: sighting in FL panhandleNo definitive proof of bird in either area
http://www.birds.cornell.edu/ivory/video_2011/
Congaree National Park, SC
Largest contiguous old growthlowland forest in U.S.
Surveyed for four years byCornell, but no ivory bills