SREL Reprint #3652

Functional traits driving species role in the structure of terrestrial vertebrate scavenger networks

Esther Sebastián-González1,2, Zebensui Morales-Reyes1, Francisco Botella1, Lara Naves-Alegre1, Juan M. Pérez-García1,3, Patricia Mateo-Tomás4,5, Pedro P. Olea6,7, Marcos Moleón8, Jomar Magalhães Barbosa1, Fernando Hiraldo9, Eneko Arrondo1,9, José A. Donázar9, Ainara Cortés-Avizanda9,10, Nuria Selva11, Sergio A. Lambertucci12, Aishwarya Bhattacharjee13,14, Alexis L. Brewer13,14, Erin F. Abernethy15, Kelsey L. Turner16, James C. Beasley16, Travis L. DeVault16, Hannah C. Gerke16, Olin E. Rhodes Jr17, Andrés Ordiz18, Camilla Wikenros19, Barbara Zimmermann20, Petter Wabakken20, Christopher C. Wilmers21, Justine A. Smith22, Corinne J. Kendall23, Darcy Ogada24, Ethan Frehner25, Maximilian L. Allen26, Heiko U. Wittmer27, James R. A. Butler28, Johan T. du Toit29, Antoni Margalida3,30, Pilar Oliva-Vidal3, David Wilson31, Klemen Jerina32, Miha Krofel32, Rich Kostecke33, Richard Inger34, Esra Per35,36, Yunus Ayhan36, Mehmet Sanci36, Ünsal Yilmazer36, Akino Inagaki37, Shinsuke Koike37, Arockianathan Samson38, Paula L. Perrig12,39, Emma E. Spencer40, Thomas M. Newsome40, Marco Heurich41,42, José D. Anadón13,14,43, Evan R. Buechley44,45, Cayetano Gutiérrez-Cánovas46, L. Mark Elbroch47, and José A. Sánchez-Zapata1

1Department of Applied Biology, Centro de Investigación e Innovación Agroalimentaria y
Agroambiental (CIAGRO-UMH), Miguel Hernández University of Elche,
Avenida de la Universidad s/n, Elche E-03202 Spain
2Department of Ecology, University of Alicante, Cra. San Vicente del Raspeig, Alicante E-03690 Spain
3Department of Animal Science, Faculty of Life Sciences and Engineering, University of Lleida,
Lleida E-25002 Spain
4Biodiversity Research Institute, University of Oviedo–Spanish National Research Council–
Principality of Asturias, Mieres E-33600 Spain
5Centre for Functional Ecology, Department of Life Sciences, University of Coimbra,
Calçada Martim de Freitas, Coimbra 3000-456 Portugal
6Departamento de Ecología, Universidad Autónoma de Madrid, Madrid E-28049 Spain
7Centro de Investigación en Biodiversidad y Cambio Global (CIBC-UAM),
Universidad Autónoma de Madrid, Madrid E-28049 Spain
8Department of Zoology, University of Granada, Granada E-18071 Spain
9Department of Conservation Biology, Doñana Biological Station-CSIC,
Avd. Americo Vespucio 26, Seville E-41092 Spain
10Department of Plant Biology and Ecology, Faculty of Biology, University of Seville,
Avda. Reina Mercedes s/n, Seville E-41012 Spain
11Institute of Nature Conservation, Polish Academy of Sciences, Krakow PL-31-120 Poland
12Grupo de Investigaciones en Biología de la Conservación, Laboratorio Ecotono, INIBIOMA,
CONICET – Universidad Nacional del Comahue, Bariloche 8400 Argentina
13Department of Biology, Queens College, City University of New York, Queens, New York 10010 USA
14Biology Program, The Graduate Center, City University of New York, New York, New York 10010 USA
15Department of Integrative Biology, Oregon State University, Corvallis, Oregon 97331 USA
16Savannah River Ecology Laboratory, Warnell School of Forestry and Natural Resources,
University of Georgia, Aiken, South Carolina 29802 USA
17Savannah River Ecology Laboratory, Odum School of Ecology,
University of Georgia, Aiken, South Carolina 29802 USA
18Faculty of Environmental Sciences and Natural Resource Management,
Norwegian University of Life Sciences, Ås NO-1432 Norway
19Grimsö Wildlife Research Station, Department of Ecology, Swedish University of Agricultural Sciences, Riddarhyttan 73993 Sweden
20Faculty of Applied Ecology, Agricultural Sciences and Biotechnology, Inland Norway University of Applied Sciences, Campus Evenstad, 2318 Norway
21Center for Integrated Spatial Research, Environmental Studies Department,
University of California, Santa Cruz, California 95064 USA
22Department of Wildlife, Fish, and Conservation Biology, University of California,
Davis, California 95616 USA
23North Carolina Zoo, 4401 Zoo Parkway, Asheboro, North Carolina 27205 USA
24The Peregrine Fund, 5668 Flying Hawk Lane, Boise, Idaho 83709 USA
25Department of Biology, University of Utah, Salt Lake City, Utah 84112 USA
26Illinois Natural History Survey, University of Illinois, Champaign, Illinois 61801 USA
27School of Biological Sciences, Victoria University of Wellington,Wellington 6012 New Zealand
28CSIRO Land andWater, Brisbane, Queensland 4001 Australia
29Department of Wildland Resources, Utah State University, Logan, Utah 84322-5230 USA
30Institute for Game and Wildlife Research, IREC (CSIC-UCLM-JCCM), Ciudad Real E-13071 Spain
31The Biodiversity Consultancy, Cambridge CB2 1SJ United Kingdom
32Department of Forestry, Biotechnical Faculty, University of Ljubljana, Ljubljana SI-1000 Slovenia
3312229 Old Stage Trail, Austin, Texas 78750 USA
34Environment and Sustainability Institute, University of Exeter, Penryn TR10 9FE United Kingdom
35Faculty of Science, Department of Biology, Gazi University, Teknikokullar, Ankara 06560 Turkey
36DEDE Nature Team, İvedik Organize Sanayi Bölgesi 1122.cad. 1473.Sok. No:4-6-8
Yenimahalle, Ankara 06374 Turkey
37Department of Environment Conservation, Tokyo University of Agriculture and Technology,
Fuchu, Tokyo 183-0054 Japan
38Department of Zoology and Wildlife Biology, Government Arts College,
The Nilgiris, Tamil Nadu 643002 India
39Department of Forest and Wildlife Ecology, University of Wisconsin-Madison,
Madison, Wisconsin 53706 USA
40School of Life and Environmental Sciences, The University of Sydney,
Sydney, New SouthWales 2006 Australia
41Department of Visitor Management and National Park Monitoring, Bavarian Forest National Park,
Freyunger Straße 2, Grafenau 94481 Germany
42Wildlife Ecology and Management, University of Freiburg, Tennenbacher Straße 4,
Freiburg 79106 Germany
43Departamento de Ciencias Agrarias y el Medio Natural, Universidad de Zaragoza, Huesca E-50009 Spain
44Smithsonian Migratory Bird Center, Washington, D.C. 20013 USA
45HawkWatch International, Salt Lake City, Utah 84106 USA
46Department of Integrative Ecology, Do~nana Biological Station-CSIC, Seville E-41092 Spain
47Panthera, 8West 40th Street, New York, New York 10018 USA

Abstract: Species assemblages often have a non-random nested organization, which in vertebrate scavenger (carrion-consuming) assemblages is thought to be driven by facilitation in competitive environments. However, not all scavenger species play the same role in maintaining assemblage structure, as some species are obligate scavengers (i.e., vultures) and others are facultative, scavenging opportunistically. We used a database with 177 vertebrate scavenger species from 53 assemblages in 22 countries across five continents to identify which functional traits of scavenger species are key to maintaining the scavenging network structure. We used network analyses to relate ten traits hypothesized to affect assemblage structure with the “role” of each species in the scavenging assemblage in which it appeared. We characterized the role of a species in terms of both the proportion of monitored carcasses on which that species scavenged, or scavenging breadth (i.e., the species “normalized degree”), and the role of that species in the nested structure of the assemblage (i.e., the species “paired nested degree”), therefore identifying possible facilitative interactions among species. We found that species with high olfactory acuity, social foragers, and obligate scavengers had the widest scavenging breadth. We also found that social foragers had a large paired nested degree in scavenger assemblages, probably because their presence is easier to detect by other species to signal carcass occurrence. Our study highlights differences in the functional roles of scavenger species and can be used to identify key species for targeted conservation to maintain the ecological function of scavenger assemblages.

Keywords: assemblage nestedness; carrion; facilitative interaction; normalized degree; obligate scavenger; olfactory acuity; social foraging; vulture

SREL Reprint #3652

Sebastián-González, E., Z. Morales-Reyes, F. Botella, L. Naves-Alegre, J. M. Pérez-García, P. Mateo-Tomás, P. P. Olea, M. Moleón, J. M. Barbosa, F. Hiraldo, E. Arrondo, J. A. Donázar, A. Cortés-Avizanda, N. Selva, S. A. Labertucci, A. Bhattacharjee, A. L. Brewer, E. F. Abernethy, K. L. Turner, J. C. Beasley, T. L. DeVault, H. C. Gerke, O. E. Rhodes Jr., A. Ordiz, C. Wikenros, B. Zimmermann, P. Wabakken, C. C. Wilmers, J. A. Smith, C. J. Kendall, D. Ogada, E. Frehner, M. L. Allen, H. U. Wittmer, J. R. A. Butler, J. T. du Toit, A. Margalida, P. Oliva-Vidal, D. Wilson, K. Jerina, M. Krofel, R. Kostecke, R. Inger, E. Per, Y. Ayhan, M. Sanci, U. Yilmazer, A. Inagaki, S. Koike, A. Samson, P. L. Perrig, E. E. Spencer, T. M. Newsome, M. Heurich, J. D. Anadón, E. R. Buechley, C. Gutiérrez-Cánovas, L. M. Elbroch, and J. A. Sánchez-Zapata. 2021. Functional traits driving species role in the structure of terrestrial vertebrate scavenger networks. Ecology 102(12): e03519.

This information was provided by the University of Georgia's Savannah River Ecology Laboratory (srel.uga.edu).