Defaunated movement: the role of animal behaviour and spatial interactions in mediating trophic cascades, niche partitioning and community dynamics in the Atlantic Forest

• Grant number: 15/11521-7
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Effective date (Start): August 01, 2015
• Effective date (End): January 31, 2020
• Field of knowledge: Biological Sciences - Ecology - Ecosystems Ecology
• Principal Investigator: Mauro Galetti Rodrigues
• Grantee: Jose Ignacio Fernandez de La Pradilla Villar
• Host Institution: Instituto de Biociências (IB). Universidade Estadual Paulista (UNESP). Campus de Rio Claro. Rio Claro , SP, Brazil
• Associated research grant: 14/01986-0 - Ecological consequences of defaunation in the Atlantic Rainforest, AP.TEM
• Associated scholarship(s): 18/20599-8 - Regulation of community and ecosystem dynamics by large tropical forest herbivores, BE.EP.PD

Abstract

Defaunation is one of the main drivers underpinning biodiversity loss and disruption of ecosystem processes and function in many systems across the world. A prominent consequence of defaunation are trophic cascades, where extirpation of keystone species can alter top-down and bottom-up regulation of ecosystem structure. For example, the removal of consumers from ecosystems can release their resources from density dependent consumption, with knock-on effects on other ecosystem processes. However, whether behavioural mechanisms such as anti-predator behaviour and social interactions contribute to limiting and/or regulating herbivore numbers and mediate trophic cascades in the wild is still a matter of contention.In large tracts of the Brazilian Atlantic forest, defaunation of keystone herbivores and predators might have led to trophic cascades. In this proposal we suggest to elucidate whether animal behaviour and spatial structure play a critical role in shaping trophic cascades, niche partitioning, community assembly and stability in this ecosystem. We will do so by evaluating the impact of several defaunation scenarios in the movement, habitat use and food selection of large herbivore and small mammals.First, we will evaluate the impact of niche partitioning, competition and predation on large herbivore movement in the Atlantic forest. For this we will use camera-traps in order to assess co-ocurrences in habitat use of white lipped peccaries (WLP) and other large herbivores and their predators, and GPS radio-collar data to investigate whether WLP movements respond to the herbivore-predator composition in their surroundings or at the landscape scale.Second, we will evaluate the impact of large herbivores on small mammal movements and niche partitioning in the Atlantic forest. We will use isotopic techniques to assess how large herbivore presence affects the diet within and across different small mammal species, and fluorescent pigments to investigate the impact of large herbivore presence on small mammal movement and habitat use. We will study responses within and across different small mammal species, so as to evaluate the potential for large herbivores and, indirectly, apex predators, to generate new ecological niches that alter the patterns of coexistence between small mammal species in the system.Third, we will evaluate the impact of herbivore movement and defaunation on spatial structure and community dynamics in the Atlantic forest using a theoretical approach. For this, we will use Individual-Based Models to investigate how defaunation and movement affects scale of interactions and spatial pattern in a spatially explicit approach. In addition, we will assess how defaunation affects stability and diversity of mammalian communities at different spatial and temporal scales using meta-community models.The combination of both empirical and theoretical approaches in a unique "natural" experimental set-up will allow us to evaluate the consequences of the extirpation of keystone mammal species from the Brazilian Atlantic forest. In doing so, we expect to inform conservation actions in these system, shed light on poorly studied and controversial aspects of animal behaviour and contribute to ecological theory.

Scientific publications

(7)

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

AKKAWI, PAULA; VILLAR, NACHO; MENDES, CALEBE P.; GALETTI, MAURO. Dominance hierarchy on palm resource partitioning among Neotropical frugivorous mammals. JOURNAL OF MAMMALOGY, v. 101, n. 3, p. 697-709, MAY 22 2020. (14/01986-0, 15/11521-7)

VILLAR, NACHO; SIQUEIRA, TADEU; ZIPPARRO, VALESCA; FARAH, FABIANO; SCHMAEDECKE, GABRIELA; HORTENCI, LUANA; BROCARDO, CARLOS RODRIGO; JORDANO, PEDRO; GALETTI, MAURO. The cryptic regulation of diversity by functionally complementary large tropical forest herbivores. JOURNAL OF ECOLOGY, v. 108, n. 1, p. 279-290, JAN 2020. (15/11521-7, 13/50424-1, 14/01986-0)

VILLAR, NACHO; ROCHA-MENDES, FABIANA; GUEVARA, ROGER; GALETTI, MAURO. Large herbivore-palm interactions modulate the spatial structure of seedling communities and productivity in Neotropical forests. PERSPECTIVES IN ECOLOGY AND CONSERVATION, v. 20, n. 1, p. 15-pg., 2022-03-02. (07/03392-6, 15/11521-7)

VILLAR, NACHO; PAZ, CLAUDIA; ZIPPARRO, VALESCA; NAZARETH, SERGIO; BULASCOSCHI, LETICIA; BAKKER, ELISABETH S.; GALETTI, MAURO. Frugivory underpins the nitrogen cycle. FUNCTIONAL ECOLOGY, v. 35, n. 2, p. 357-368, FEB 2021. (14/01986-0, 16/25197-0, 18/20599-8, 15/11521-7, 13/50424-1, 18/00212-1)

SOUZA, YURI; VILLAR, NACHO; ZIPPARRO, VALESCA; NAZARETH, SERGIO; GALETTI, MAURO. Large mammalian herbivores modulate plant growth form diversity in a tropical rainforest. JOURNAL OF ECOLOGY, v. 110, n. 4, p. 15-pg., 2022-02-08. (18/20599-8, 13/50424-1, 15/11521-7, 19/05538-5, 14/01986-0)

VILLAR, NACHO; SIQUEIRA, TADEU; ZIPPARRO, VALESCA; FARAH, FABIANO; SCHMAEDECKE, GABRIELA; HORTENCI, LUANA; BROCARDO, CARLOS RODRIGO; JORDANO, PEDRO; GALETTI, MAURO. The cryptic regulation of diversity by functionally complementary large tropical forest herbivores. JOURNAL OF ECOLOGY, AUG 2019. (14/01986-0, 15/11521-7, 13/50424-1)

MAGIOLI, MARCELO; VILLAR, NACHO; JORGE, MARIA LUISA; BIONDO, CIBELE; KEUROGHLIAN, ALEXINE; BRADHAM, JENNIFER; PEDROSA, FELIPE; COSTA, VLADIMIR; MOREIRA, MARCELO ZACHARIAS; PASCHOALETTO MICCHI DE BARROS FERRAZ, KATIA MARIA; et al. Dietary expansion facilitates the persistence of a large frugivore in fragmented tropical forests. ANIMAL CONSERVATION, DEC 2021. (14/01986-0, 14/10192-7, 14/50434-0, 16/15436-7, 15/18381-6, 15/11521-7, 14/09300-0)