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Eastern Screech Owl


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Eastern Screech Owl Project Presentation for Life on the Planet Earth Class. Part of NYC Ecology Wiki

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Eastern Screech Owl

  1. 1. Eastern Screech-Owl (Megascops asio) By Liz Yaslik NYC Ecology Wiki
  2. 2. About the Owl  Small in size among other “eared” owls  Nocturnal raptor  Usually red or gray in color  Found in suburban and rural areas  Non- migratory (stays relatively close to home area)
  3. 3. Flickr Photo by Bobtravis
  4. 4. Habitat  Found in suburban and rural areas  Cavity nester but do not create the cavities themselves  Lives in many parks in New York City  Willing to use nest boxes placed in parks
  5. 5. Screech Owl in Nest Box Flickr Photo by Gilintx
  6. 6. Central Park Reintroduction  Native to Central Park for decades  Decrease in population from 1930s-1950s  New York City Urban Park Rangers worked to reintroduce the owl into the park  1998- NYCUPR released 6 owls into Central Park -the owls were not equipped with monitoring devices  2001 & 2002- NYCUPR released 32 owls into Central Park - 30 of the owls were equipped with radio transmitters
  7. 7. Central Park New York City Flickr Photo by Jimbowen0306
  8. 8. Central Park Reintroduction  Released owls were found to have 23% survival rate  Suggests that about 77% of owls died or left the area  Owl deaths due to lack of food, predation, impact with objects, or rodenticide poison  2003- None of the 7 owls released in 1998 were found  7 owls from the 2001-2 release remained in the park
  9. 9. Flickr Photo by Dobak
  10. 10. Tracking the Owls  Owls were banded and equipped with radio transmitter backpacks One month after 2001 release, 12 of 17 birds  equipped with radio backpacks had been separated from backpacks By 2003 all transmitter batteries had died  Central Park bird watchers contacted researchers  about sightings Call surveys using owl calls  Collecting owl pellets to locate 
  11. 11. Eastern Screech Owl Sightings Since 2001 Map Created By Liz Yaslik using Google Earth
  12. 12. Problems with Reintroduction  Most of the owls had slipped out of transmitter packs  Batteries of packs died  A decrease in bird watchers could lead to a decrease in bird sightings, not necessarily a decrease in owls
  13. 13. Possible Causes of Owl Decrease  Lack of males or females, slowing reproduction rates  Poor weather conditions  Increase in owl predators  Collision of owls with other structures  Habitat or cavity destruction/competitors  Fewer bird watchers
  14. 14. Red Phase Eastern Screech Owl Flickr Photo by rbs10025
  15. 15. Importance of Reintroduction  Maintain biodiversity in New York City  Necessary for park ecosystem  Create breeding pairs
  16. 16. Click to play virtual tour
  17. 17. Personal Observations  Relatively difficult to track the owls  Radio transmitters are not reliable  Most owls left Central Park area, the owls may know which areas are best
  18. 18. Recommendations  Since 77% of reintroduction population left the area, discontinue reintroduction Research why owls choose other areas  Keep track of number of males and females  Check availability of owl habitats, add more nest  boxes if necessary Track the owls’ available food sources and  reproduction rates
  19. 19. Bibliography Bibliography  Andrle, Robert F. 1987. The Atlas of Breeding Birds in New York State. Ed. Janet R. Carroll.  Ithaca: Cornell University Press.  Audubon New York. Audubon Sharon: Resident Animals, Our Resident Screech Owls.   Belthoff, James R. 1993. Home Ranges of Adult and Juvenile Eastern Screech-Owls: Size,  Seasonal Variation and Extent of Overlap. J. Raptor Res. 27: 8-15.  DeCandido, Robert. 2002. quot;The Screech-Owls of Central Park.quot; Birder's World 16, no. 6: 58.   Academic Search Complete, EBSCOhost (accessed March 1, 2009).   DeCandido, Robert. 2005. History of the Eastern Screech-Owl (Megascops asio) in New York  City 1867-2005. Urban Habitats 3.1 (2005): 1-17.  Gehlbach, F.R. 1995. Eastern screech-owl (Otus asio). In Poole, A. & F. Gill, (Eds.) The birds of  North America (No. 165). Philadelphia: Academy of Natural Sciences; Washington, DC:  American Ornithologists' Union.  Nagy, Christopher. “The Eastern Screech Owl Reintroduction Program in Central Park, New  York City: Habitat, Survival, and Reproduction” (M.S. Biology Thesis, Fordham  University, 2004), 1-46.  New York City Department of Parks and Recreation. The Daily Plant: Screech Owls Return to  Central Park.  Robbins, Chandler S., Bertel Bruun, and Herbert S. Zim. 1966. A Guide to Field Indentification:  Birds of North America. New York: Golden Press.  Sibley, David A. 2001. National Audubon Society: The Sibley Guide to Bird Life and Behavior.  Eds. Elphick, Chris, John B. Dunning Jr. New York: Alfred A. Knopf, Inc. 