Date of Award
2019
Publisher
North Dakota State University
Document Type
Thesis
Degree Awarded
Master of Science (MS)
Program
Environmental and Conservation Science
Department
Biological Sciences
College
Graduate and Interdisciplinary Studies
Faculty Advisor
Klug, Page E.
Description
Across North America, blackbirds (Icteridae) depredate high-energy crops, such as sunflower (Helianthus annuus), placing an economic burden on producers. Chemically-defended crops, in the form of human-applied repellents, may induce birds to forage elsewhere if a learned aversion can be established. However, repellent deployment must be feasible for producers at the scale of commercial agriculture. Thus, my main objective was to evaluate the efficacy of anthraquinone-based repellents applied to ripening sunflower for reducing blackbird damage. I conducted concentration response (no-choice) and preference tests (two-choice) to evaluate repellent efficacy on captive blackbirds using application strategies practical for agricultural producers. I evaluated field application strategies to assess the potential for broad-scale application using new drop-nozzle technology. Additionally, I describe behavior of captive blackbirds as they interact with ripening sunflower to further inform repellent application. Our results support the conclusion that application of anthraquinone-based repellents is not currently a feasible option for ripening sunflower.
Recommended Citation
Kaiser, Brandon Amberg, "Chemical Repellents for Reducing Blackbird Damage on Mature Sunflowers: The Importance of Plant Structure and Avian Behavior in Field Applications" (2019). Environmental and Conservation Sciences. 67.
https://digitalcommons.ndsu.edu/env-conservation-sci/67
Author ORCID Identifier
0000-0003-3407-5273
Handle Identifier
https://hdl.handle.net/10365/29793