Dangerous misperceptions with consequences: survival of Eastern cottontails on restored grasslands surrounded by agriculture

Nawrocki, Julia A

Permalink

https://hdl.handle.net/2142/97407 Copy

Description

Title

Dangerous misperceptions with consequences: survival of Eastern cottontails on restored grasslands surrounded by agriculture

Author(s)

Nawrocki, Julia A

Issue Date

2017-04-27

Director of Research (if dissertation) or Advisor (if thesis)

Schooley, Robert L.

Committee Member(s)

• Ward, Michael P.
• Heske, Edward J.

Department of Study

Natural Res & Env Sci

Discipline

Natural Res & Env Sciences

Degree Granting Institution

University of Illinois at Urbana-Champaign

Degree Name

M.S.

Degree Level

Thesis

Keyword(s)

• Eastern cottontail
• Restoration
• Restored grasslands
• Agroecosystem
• Perceived risk
• Survival
• Giving-up density

Abstract

Habitat loss and degradation is a main threat to biodiversity, and the expansion of intensive agricultural practices has negatively affected wildlife populations worldwide. To counteract these effects, large-scale restoration programs have been developed. In the Midwestern United States, where tallgrass prairies have been reduced by >99%, the Conservation Reserve Program has created patches of grassland habitat within a larger matrix dominated by agricultural fields that are temporally dynamic due to planting and harvesting of crops. The effects of the surrounding landscape on restoration success of wildlife species is largely unknown. My main objective was to examine how landscape processes interact with real and perceived predation risk to affect survival of a key herbivore and important prey species, the eastern cottontail (Sylvilagus floridanus), in restored grassland habitats and the surrounding agricultural matrix. From June 2014 through June 2016, I radio-collared 95 cottontails and tracked their movements until the transmitter failed or mortality occurred. I then constructed known-fate models in program MARK to identify factors that affected survival rates. I also conducted giving-up density (GUD) experiments in grasslands and adjacent agricultural fields to determine if there were differences in perceived predation risk. As expected, survival of cottontails was higher when they used restored grasslands relative to when they used surrounding habitats. Contrary to my prediction, however, cottontails did not accurately perceive predation risk as they perceived agricultural fields to be safer than grasslands. This mismatch could be due to their emphasis on protecting themselves from avian predation rather than mammalian predation. However, mammals were the main predators in this system, predominately coyotes (Canis latrans). My study demonstrates how adjacency of restoration sites to other landscape elements can produce unintended consequences and highlights the complexities of achieving restoration in a highly altered landscape.

Graduation Semester

2017-05

Type of Resource

text

Permalink

http://hdl.handle.net/2142/97407

Copyright and License Information

Copyright 2017 Julia Nawrocki

Owning Collections