Graduate Thesis Or Dissertation

 

Effects of jet aircraft overflights and other potential disturbances on behavioral responses and productivity of nesting peregrine falcons Public Deposited

Downloadable Content

Download PDF
https://ir.library.oregonstate.edu/concern/graduate_thesis_or_dissertations/k643b548r

Descriptions

Attribute NameValues
Creator
Abstract
  • In order to examine the potential impact of military jet overflights and other disturbances on productivity of peregrine falcons (Falco peregrinus), we observed behavioral reactions of peregrines to disturbances at nests along the Tanana River, Alaska during the 1995-1997 breeding seasons. Military jets conducted low-altitude flights over a sample of nests under observation in each year (experimental nests), while other nests were not intentionally overflown (reference nests). Other disturbances occurred at random. Animal noise monitors (ANMs), which collect and store data on noise disturbance levels, were deployed at each observed nest. A total of 878 above-threshold (≥ 85 dB) overflights were recorded by the ANMs during the course of the study. A total of 401 close (defined as ≤ 1000 m slant distance from the nest) overflights by subsonic F-16, F-15, A-10, Harrier, Jaguar, or Tornado jet aircraft were recorded during observations. Close overflights by military jets accounted for 63% of all observed potential disturbances at experimental nests; they accounted for 2.6% of all observed potential disturbances at reference nests. Other potential disturbances at reference nests included civilian fixed-wing aircraft (41%), boats (33%), avian predators (17%), helicopters (5%), and mammalian predators (1%). Peregrine falcons responded differently to animate and inanimate sources of disturbance, and responded most intensely and most frequently to other raptors, particularly conspecifics. Flight reactions were common, but not in response to inanimate sources. Among inanimate potential disturbances, falcons responded most intensely to boats (6% of reactions involved flight), and least intensely to helicopters (3%) and fixed-wing aircraft (2%). Intensity of reactions to military jets was indistinguishable from that to either boats or other aircraft. Intense behavioral responses (including flight reactions) to military jet overflights were rarely observed in this study, even at slant distances <500 m, and no intense behavioral responses were observed at slant distances >550 m. Peregrine falcon productivity (number of fledglings produced per nesting attempt) in the study area was within the normal range for Interior Alaska and the Tanana River. Dose of jet aircraft disturbance was not correlated with productivity. Productivity was, however, negatively correlated with reactivity of both individual falcons and mated pairs. Those falcons that responded more intensely to overflights tended to have lower productivity. The sensitivity of breeding peregrine falcons to low-altitude jet overflights is a better indicator of subsequent productivity than actual dose of overflights. This is likely a reflection of lower parental quality/investment among breeding pairs with high reactivity (i.e., younger, less experienced parents are less likely to be productive).
Resource Type
Date Available
Date Copyright
Date Issued
Degree Level
Degree Name
Degree Field
Degree Grantor
Commencement Year
Advisor
Committee Member
Non-Academic Affiliation
Subject
Rights Statement
Peer Reviewed
Language
Digitization Specifications
  • File scanned at 300 ppi (Monochrome, 8-bit Grayscale) using ScandAll PRO 1.8.1 on a Fi-6670 in PDF format. CVista PdfCompressor 4.0 was used for pdf compression and textual OCR.
Replaces
Additional Information
  • description.provenance : Submitted by John Valentino (valentjo@onid.orst.edu) on 2012-09-17T21:23:16Z No. of bitstreams: 1 NordmeyerDanaL1999.pdf: 5066462 bytes, checksum: 0345c390245a57924195b1b4e6b811cf (MD5)
  • description.provenance : Approved for entry into archive by Patricia Black(patricia.black@oregonstate.edu) on 2012-09-18T19:58:35Z (GMT) No. of bitstreams: 1 NordmeyerDanaL1999.pdf: 5066462 bytes, checksum: 0345c390245a57924195b1b4e6b811cf (MD5)
  • description.provenance : Made available in DSpace on 2012-09-18T19:58:35Z (GMT). No. of bitstreams: 1 NordmeyerDanaL1999.pdf: 5066462 bytes, checksum: 0345c390245a57924195b1b4e6b811cf (MD5) Previous issue date: 1999-04-08
  • description.provenance : Approved for entry into archive by Patricia Black(patricia.black@oregonstate.edu) on 2012-09-18T19:56:05Z (GMT) No. of bitstreams: 1 NordmeyerDanaL1999.pdf: 5066462 bytes, checksum: 0345c390245a57924195b1b4e6b811cf (MD5)

Relationships

Parents:

This work has no parents.

In Collection:

Items