Biodiversity and Conservation

, Volume 28, Issue 5, pp 1109–1127 | Cite as

Invasive feral swine damage to globally imperiled steephead ravine habitats and influences from changes in population control effort, climate, and land use

  • Richard M. EngemanEmail author
  • Erica Laine
  • John Allen
  • Jeremy Preston
  • William Pizzolato
  • Brett Williams
  • Amanda Stevens Kreider
  • Dennis Teague
Original Paper
Part of the following topical collections:
  1. Invasive species


Steephead ravines are unusual geological features primarily occurring in Florida’s panhandle, a biodiversity hotspot. The unique habitats formed by steepheads are extremely valuable biodiversity resources within this larger area of great biodiversity. Eglin Air Force Base (EAFB) is essential for global conservation of steepheads because this vast area holds the greatest number under single ownership. Steepheads are significantly threatened by feral swine rooting damage. A decade-long investigation of EAFB’s steepheads assessed the following: (1) severity of swine damage to steepheads, (2) changing levels of swine control on swine population and damage, (3) changing climatic conditions on damage, (4) changing military land use on damage (5) bioeconomics of damage. Swine damage to 21 EAFB steepheads was assessed 5 times over 10 years. Swine populations were indexed 8 times. Damage and population estimates were related to control effort, military land use, and climate variables to assess influences on damage levels. Monetary values were applied to estimates of total damage across all steepheads. Full control staffing rapidly reduced feral swine abundance and steephead damage. Reduced control staffing and reduced access from increased military activities allowed population rebound and increased damage. Drought possibly increased susceptibility to damage because steepheads provide a steady water source despite climatic circumstance. Estimated damage values across EAFB’s steepheads (excluding other resources damaged) was 1.5–11.3 times more than annual control costs. Effective swine control greatly reduces steephead damage. Technological advances may overcome access issues from changing land use. Swine control is a cost-effective steephead conservation approach.


Animal damage management Biodiversity Bioeconomics Ecological sampling Invasive species Sus scrofa 



This research was supported by the intramural research programs of the U.S. Department of Agriculture and U.S. Department of Defense.


This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.


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Copyright information

© This is a U.S. government work and its text is not subject to copyright protection in the United States; however, its text may be subject to foreign copyright protection 2019

Authors and Affiliations

  • Richard M. Engeman
    • 1
    Email author
  • Erica Laine
    • 2
  • John Allen
    • 3
  • Jeremy Preston
    • 2
  • William Pizzolato
    • 2
  • Brett Williams
    • 2
  • Amanda Stevens Kreider
    • 2
    • 4
  • Dennis Teague
    • 2
  1. 1.National Wildlife Research CenterFort CollinsUSA
  2. 2.Eglin AFB Natural ResourcesNicevilleUSA
  3. 3.USDA/APHIS/Wildlife ServicesGainesvilleUSA
  4. 4.TijerasUSA

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