CORRESPONDENCE Bombing for Biodiversity in the United States: Response to Zentelis & Lindenmayer 2015 Jocelyn L. Aycrigg 1, R. Travis Belote 2, Matthew S. Dietz 3, Gregory H. Aplet 4, & Richard A. Fischer 5 1 Department of Fish and Wildlife Sciences, University of Idaho, Moscow, Idaho, USA 2 The Wilderness Society, Bozeman, Montana, USA 3 The Wilderness Society, San Francisco, California, USA 4 The Wilderness Society, Denver, Colorado, USA 5 U.S. Army Engineer R&D Center, Environmental Lab, Vicksburg, Mississippi, USA Keywords Biodiversity; Department of Defense; ecological systems; military training areas; representation; United States. Correspondence Jocelyn L. Aycrigg, Department of Fish and Wildlife Sciences, University of Idaho, 875 Perimeter Drive MS-1136, Moscow, ID 83844-1136, USA. Tel: 208-885-3901; fax: 208-885-9080. E-mail: aycrigg@uidaho.edu Received 6 July 2015 Accepted 14 July 2015 Editor Edward Game doi: 10.1111/conl.12197 Zentelis & Lindenmayer (2015) contend military training areas (MTAs) have the potential to make a significant formal contribution to biodiversity conservation, yet their conservation value has not been rigorously assessed. We believe their paper is an important step in raising awareness of the potential conservation value of MTAs to policy makers, scientists, and conservation professionals. Here, we offer an empirical evaluation of their statements regarding size, distribution, and representation of ecological systems (i.e., vegetation communities) within MTAs for the contiguous United States (CONUS) by comparing MTAs with lands managed by other U.S. federal agencies. We used lands managed by Department of Defense (DoD) as a proxy for MTAs. By combining the Protected Areas Database of the U.S. (PAD-US; USGS-GAP 2012) and the National GAP Land Cover (USGS-GAP 2011), we determined total number of ecological systems across all units of DoD and other agencies; and proportion of each ecological system that each agency represents across all lands. DoD lands occur in every state (Figure S1) and represent 467 of 565 total ecological systems within CONUS on 8.1 million hectares (Table S1). This ecological diversity is exceeded only by the National Park Service (NPS), which represents 479 ecological systems across 10.2 million hectares. In contrast, U.S. Forest Service (USFS) and Bureau of Land Management (BLM) lands, despite being 8.5 and 8.6 times larger than DoD lands, represent only 458 and 293 ecosystems, respectively. Therefore, even though DoD lands comprise only 5% of the total area of federal lands, they represent 82.6% of the diversity 306 Conservation Letters, July/August 2015, 8(4), 306 307 Copyright and Photocopying: C 2015 The Authors. Conservation Letters published by Wiley Periodicals, Inc. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
J. L. Aycrigg et al. Bombing for biodiversity in the United States of ecological systems, whereas USFS and BLM comprise 42% and 43% of the total federal land area, but neither represents as much diversity as DoD lands. Similarly, Stein et al. (2008) found DoD lands disproportionately represented more imperiled species (e.g., vascular plants) per unit area than other federal lands. DoD lands also contribute to total representation of ecological systems on federal lands, as three ecological systems occur on DoD lands only. These ecological systems are relatively rare (i.e., occur on <10,000 hectares throughout CONUS) and have >50 100% of their area on federal lands within DoD. Similar to other federal agencies, the majority of ecological systems have <10% of their entire or federal distribution within DoD lands (Figure S2, USFS is an exception). As part of the entire collective of federal lands, DoD lands increase federal representation of 50 ecological systems by >5% (Figure S3). Our results are likely a consequence of a mandate that DoD lands be intentionally distributed across the U.S. to train the military under a variety of geographic conditions. They contrast with lands managed by BLM, NPS, USFS, and U.S. Fish and Wildlife Service (FWS), which have been obtained through various opportunities and agency-specific conservation priorities (Aycrigg et al. 2013) and not specifically established to maximize biological diversity (Scott et al. 2001). Our empirical analysis of DoD lands within CONUS support the contentions of Zentelis & Lindenmayer (2015) that DoD lands (i.e., MTAs) contribute to biodiversity conservation and should be considered a conservation asset. Supporting Information Additional Supporting Information in tables and figures may be found in the online version of this article at the publisher s web site: Table S1. Total area (in hectares), number (i.e., gamma diversity across all units), and unique number of ecological systems within CONUS among federal agencies. DoD lands (our proxy for MTAs) are the second most diverse federal land management agency, second only to the NPS, which contains over 27% more area. We excluded developed land and open water. These data are based on the Protected Areas Database of the United States (PAD-US; USGS-GAP 2012). Figure S1. Department of Defense lands in the contiguous United States. We excluded developed land and open water. Lines were thickened to increase visibility of smaller areas. These data are based on the Protected Areas Database of the United States (PAD-US; USGS-GAP 2012). Figure S2. Number of ecological systems in each federal land category shown by percent area of the range (i.e., total area in CONUS) of each ecological system (top) and shown by percent area across all federal lands for those ecological systems (bottom). Our federal land categories are Department of Defense (DoD), Bureau of Land Management (BLM), U.S. Fish and Wildlife Service (FWS), U.S. Forest Service (USFS), National Park Service (NPS), and other federal lands (Other fed). We excluded developed land and open water. Based on the Protected Areas Database of the United States (PAD-US; USGS-GAP 2012). Figure S3. The distribution of the contribution of Department of Defense (DoD) lands to representation of ecological systems within CONUS. We calculated representation (i.e., area of each ecosystem on all federal lands / total area of each ecosystem across CONUS 100) for each ecological system when excluding DoD lands in the federal collective and including DoD lands. The difference in representation between exclusion and inclusion of DoD lands is considered the contribution of DoD lands to representation for all 565 ecosystems occurring within CONUS. One ecological system that increased in representation to >50.1% when including DoD lands is not visible. We excluded developed land and open water. Based on the Protected Areas Database of the United States (PAD-US; USGS-GAP 2012). References Aycrigg, J.L., Davidson, A., Svancara, L.K., et al. (2013). Representation of ecological systems within the protected areas network of the continental United States. PLoS ONE, 8, e54689. Doi:10.1371/journal.pone.0054689. Scott, J.M., Davis, F.W., McGhie, G., et al. (2001). Nature reserves: do they capture the full range of America s biological diversity. Ecol. Appl., 11, 999 1007. Stein, B.A., Scott, C., & Benton, N. (2008). Federal lands and endangered species: the role of military and other federal land in sustaining biodiversity. Conserv. Biol., 58, 339 347. US Geological Survey, Gap Analysis Program (USGS-GAP). (2011). National GAP Land Cover, Version 2. Available from http://gapanalysis.usgs.gov. Accessed 2 February 2015. US Geological Survey, Gap Analysis Program (USGS-GAP). (2012). Protected Areas Database of the United States (PAD-US), version 1.3. Available from http://gapanalysis.usgs.gov. Accessed 2 February 2015. Zentelis, R. & Lindenmayer, D. (2015). Bombing for biodiversity enhancing conservation values of Military Training Areas. Conserv. Lett., doi: 10.1111/conl. 12155. Conservation Letters, July/August 2015, 8(4), 306 307 Copyright and Photocopying: C 2015 The Authors. Conservation Letters published by Wiley Periodicals, Inc. 307
Supplemental Table 1. Total area (in hectares), number (i.e., gamma diversity across all units), and unique number of ecological systems within contiguous U.S. (CONUS) among federal agencies. Department of Defense (DoD) lands (our proxy for MTAs) are the second most diverse federal land management agency, second only to the NPS, which contains over 27% more area. We excluded developed land and open water. These data are based on the Protected Areas Database of the United States (PAD-US; USGS-GAP 2012). Federal agency Area (millions of hectares) Number of ecological systems Number of unique ecological systems National Park Service (NPS) 10.3 479 4 Department of Defense (DoD) 8.1 467 3 U.S. Fish & Wildlife Service (FWS) 4.4 460 10 U.S. Forest Service (USFS) 68.7 458 11 Other federal lands 1.5 352 0 Bureau of Land Management (BLM) 69.8 293 3