Pumas as ecosystem engineers: ungulate carcasses support beetle assemblages in the Greater Yellowstone Ecosystem
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Ecosystem engineers create physical changes in abiotic and biotic material, and through this process control the availability of resources for other species. Predators that abandon large portions of their prey may be ecosystem engineers that create habitat for carrion-dependent invertebrates that utilize carcasses during critical life-history periods. Between 04-May-2016 and 04-Oct-2016, we sampled beetle assemblages at 18 carcasses of prey killed by pumas and matching control sites in the southern Greater Yellowstone Ecosystem, USA, to measure the extent to which beetle families utilized these carcass “habitats”. We used generalized linear-mixed models and linear-mixed effect models to examine changes in beetle abundance, species richness, and Simpson’s Index of Diversity. We estimated kill rates and carrion production rates for individual pumas to better assess the impact of pumas on invertebrate communities. We collected 24,209 beetles representing 215 species. We identified eight beetle families that had significantly higher abundance at carcasses than control sites. Carcasses had a statistically large to very large effect (determined using Cohen’s d) on beetle abundance, richness, and diversity for the initial 8 weeks of sampling. Our research revealed strong effects of an ecosystem engineer on beetle assemblages while highlighting the potential role of apex predators in creating and modifying physical habitats for carrion-dependent species. This suggests that there may be consequences for invertebrate communities where apex predators exist at reduced numbers or have been eradicated. The ecological role of invertebrates is often overlooked, yet they are essential taxa that provide critical ecological services upon which we depend.
KeywordsBiodiversity Carrion Invertebrates Pumas Scavenging
We thank the Summerlee Foundation, Pace University, Hofstra University, Charles Engelhard Foundation, Eugene V. & Clare E. Thaw Charitable Trust, National Geographic Society (Grant C236-13), Connemara Fund, Tapeats Foundation, Community Foundation of Jackson Hole, Hogan Films, Ecotour Adventures, Mr. and Mrs. Folger, L. Westbrook, The Scully family, Mr. and Mrs. Haberfeld, Mr. and Mrs. Robertson, Mr. and Mrs. Heskett, Mr. and Mrs. Burgesses, D. Bainbridge, T. Thomas, and A. Smith for financial support of the project. We thank M. Ivie for his assistance to beetle identification. We also thank M. Peziol, C. O’Malley, A. Kusler, J. Williams, B. Smith and S. Smith for contributions to fieldwork. We are grateful for the feedback from the handling editor, two anonymous reviewers, and R. Brandl, Editor in Chief, Terrestrial Invertebrate.
Author contribution statement
JMB and LME conceived and designed the experiment. JMB and LME conducted the field work. JMB and MEAL conceived and performed statistical analyses. LS and AK conducted laboratory work on the beetle dataset. JMB and LME wrote the manuscript, with constructive feedback and additions from all authors. HBQ, MMG, and RJS provided institutional support for the work and graduate student training.
Compliance with ethical standards
Conflict of interest
The authors declare that they have no conflict of interest.
All procedures performed in this study involving animals were in accordance with the ethical standards of the American Society of Mammals and were approved by two independent Institutional Animal Care and Use Committees (IACUC): the Jackson IACUC (Protocol 027-10EGDBS-060210) and National Park Service IACUC (IMR_GRTE_Elbroch_Cougar_2013-2015).
- Ackerman BB, Lindzey FG, Hemker TP (1986) Predictive energetics model for cougars. In: Miller SD, Everett DD (eds) Cats of the world: biology, conservation, and management. National Wildlife Federation, Washington, DC, pp 333–352Google Scholar
- Anderson RS, Peck SB (1985) The carrion beetles of Canada and Alaska: Coleoptera, Silphidae and Agyrtidae (the insects and Arachnids of Canada, Part 13). Canadian Government Publishing Centre, OttawaGoogle Scholar
- Danvir RE, Lindzey FG (1981) Feeding behavior of a captive cougar on mule deer. Encyclia 58:50–56Google Scholar
- Jones CG, Lawton JH, Shachak M (1997) Positive and negative effects of organisms as physical ecosystem engineers. Ecology 78:1946–1957. https://doi.org/10.1890/0012-9658(1997)078%5b1946:PANEOO%5d2.0.CO;2 CrossRefGoogle Scholar
- Lövei GL, Sunderland KD (1996) Ecology and behavior of ground beetles (Coleoptera: (Carabidae). Annu Rev Entomol 41:231–256. https://doi.org/10.1146/annurev.en.41.010196.001311 CrossRefGoogle Scholar
- Power ME, Tilman D, Estes JA, Menge BA, Bond WJ, Mills LS, Daily G, Castilla JC, Lubchenco J, Paine RT (1996) Challenges in the quest for keystones: identifying keystone species is difficult—but essential to understanding how loss of species will affect ecosystems. Bioscience 46:609–620. https://doi.org/10.2307/1312990 CrossRefGoogle Scholar
- Ratcliffe BC (1996) The carrion beetles (Coleoptera: Silphidae) of Nebraska. Bull Univ Nebraska State Museum 13:1–100Google Scholar
- Ripple WJ, Estes JA, Beschta RL, Wilmers CC, Ritchie EG, Hebblewhite M, Berger J, Elmhagen B, Letnic M, Nelson MP, Schmitz OJ, Smith DW, Wallach AD, Wirsing AJ (2014) Status and ecological effects of the world’s largest carnivores. Science 343:1241484. https://doi.org/10.1126/science.1241484 CrossRefGoogle Scholar
- Soulé ME, Estes JA, Miller B, Honnold DL (2005) Strongly interacting species, conservation policy, management, and ethics. Bioscience 55:168–176. https://doi.org/10.1641/0006-3568(2005)055%5b0168:SISCPM%5d2.0.CO;2 CrossRefGoogle Scholar
- Trumbo ST (1992) Monogamy to communal breeding: exploitation of a broad resource base by burying beetles (Nicrophorus). Ecol Entomol 17:289–298. https://doi.org/10.1111/j.1365-2311.1992.tb01060.x CrossRefGoogle Scholar
- Vaurie P (1955) A revision of the genus Trox in North America (Coleoptera: Scarabaeidae). Bull Am Mus Nat Hist 106:1–89Google Scholar
- Warnes GR, Bolker B, Lumley T (2018) gtools: Various R Programming Tools. R package version 3.8.1. https://CRAN.R-project.org/package=gtools
- Wilsey BJ, Potvin C (2000) Biodiversity and ecosystem functioning: importance of species evenness in an old field. Ecology 81:887–892. https://doi.org/10.1890/0012-9658(2000)081%5b0887:BAEFIO%5d2.0.CO;2 CrossRefGoogle Scholar
- Wright JP, Jones CG (2006) The concept of organisms as ecosystem engineers then years on: progress, limitations, and challenges. Bioscience 56:203–209. https://doi.org/10.1641/0006-3568(2006)056%5b0203:TCOOAE%5d2.0.CO;2 CrossRefGoogle Scholar