Our research on the nature of ecological interactions in marine animals —among themselves and with humans— helps to reveal the extent to which such interactions influence the behavior of individuals and the dynamics of their populations, societies and cultures.

The dolphin-fisher project

Mechanisms and resilience of human-dolphin mutualism

PIs: Mauricio Cantor, Damien Farine, Fábio Daura-Jorge
Graduate Students: Alexandre Machado, João Valle-Pereira, Bruna Santos
Collaborators: Carolina Bezamat, Bianca Romeu, Pedro Castilho, Natalia Hanazaki, Paulo Simões-Lopes

Project Summary: How does cooperative behavior emerge in a selfish world? This intriguing question has stimulated debate among scholars, across disciplines. From the perspective of evolutionary theory, cooperation is a paradox: Why would an individual spend energy to benefit others? Multidisciplinary research gave rise to a solid theoretical foundation proposing routes to the evolution of cooperation. Theoretically, cooperation should persist when the benefits to individual overweigh the costs. However, quantifying such trade-offs in the wild remains challenging. This project quantitatively evaluates the direct benefits accrued from foraging interactions between wild bottlenose dolphins and artisanal fishermen in Brazil, an intriguing cooperation between two top predators to access a common resource: mullet fish. The accessibility of this system presents a rare opportunity to study the fine-scale details of cooperation in the wild. Furthermore, the interaction takes place between individuals of different species it allows studying direct benefits without the confounding effects of inclusive fitness. We collected unprecedented empirical data, by simultaneously recording the interactions from above and underwater, using a multiplatform sampling that combines photography, acoustic recording, overhead drone video footage and a novel sonar-based imaging system that generate high-resolution underwater imaging. This project assesses the underlying mechanisms of this rare human-animal interaction, by quantifying the direct benefits for both parties. Understanding the dynamics of this system opens the dialogue on the conservation of an interaction that is ecologically important for dolphins, and culturally and economically important for local fishermen.

Funded by

PELD-SELA: Long-term ecological project on the Laguna Estuarine System and Adjacent Areas

PIs: Mauricio Cantor, Damien Farine, Fábio Daura-Jorge, Jorge Rodriguez, David Dantas and 20 other collaborators and Graduate students

Project Summary: Can a cooperative behavior influence the dynamics of the population, the community and an ecological system? This is a large collaborative research program from the Brazilian Ministry of Science and Technology to investigate the ecological drives, ecosystem and bioeconomic consequences of specialized cooperation between humans and dolphins. It provides a rare opportunity to combine empirical data with theoretical models to answer this question through the long-term study of interspecific cooperation between dolphins and artisanal fishers foraging together for a common resource—mullet fish. This interaction is part of the local cultural repertoire—of both fishers and dolphins—for over 120 years, but little is known about the mechanisms that maintain this interaction, and if this interaction has consequences for populations and ecosystems. It is crucial to understanding such mechanisms if we are to predict the minimum conditions of resource availability and anthropogenic disturbances to maintain the ecosystem services provided by this interaction. From a systematic collection of empirical data, this project investigates the behavioral mechanisms of the dolphin-fisher interaction, and estimate population parameters of dolphins, fishers and fishing resources. As this interaction is part of a larger ecosystem, the Laguna Estuarine System (SEL), we need to understand how it can influence higher levels of organization—both the ecosystem and the human social and economic contexts. We combine data from the biological communities with data from the human economical activities data in ecosystem and bioeconomic models to find economically optimal, socially fair and ecologically sustainable solutions for managing the local fisheries.

Funded by

Social foraging and hunting performance in human cooperative systems

Co-PIs: Mauricio Cantor, Fábio Daura-Jorge, Natalia Hanazaki, Damien Farine
Key Collaborators: Jens Pruessner, Hanja Brandl
Graduate students: João Valle-Pereira, Bruna Santos-Silva

Project Summary: For over a century, artisanal net-casting fishers have been cooperating with wild dolphins to catch the same prey (migratory mullets) in southern Brazil. This project combines long-term socioeconomic data on the artisanal fishers, with fine-scale behavioral tracking of their fishing performance and physiological correlates to investigate the drivers on the human side of this unique predator-prey system. Using interviews collected over the past 16 years, we explore the role of non-material benefits, such as social connectedness and peer-reputation, of the propensity for fishers to engage in social foraging. Using drone-based tracking, we quantify their fishing performance when interacting with the dolphins. More recently, we have been using high-resolution physiological and position data loggers to study the ecophysiology of predators in the context of this predator-prey systems. While many studies have previously targeted dynamics surrounding the prey, the predator perspective is basically unexplored. We thus want to investigate links between predator experience, foraging performance and cooperation using a state-of the art multiplatform tracking system that includes monitoring heart beats and fine scale movements of artisanal fishers as cooperative predators.

Funded By

The SEAFOOD project

Social Ecology And Foraging of Dolphins

Photo credit: Tropical Dolphin Research Foundation

To be started in 2023
PIs: Mauricio Cantor, Jeremy Kiszka, Leigh Torres, Jennifer Lewis
Graduate students: João Valle-Pereira, Alexandre Machado, Mahmud Rahman

Project Summary: Humans value diversity of culture. It is what drives us to travel to new places. It is what we believe gives our groups strength. While we understand and value this diversity in ourselves, would we do the same with animals? In some species there is also cultural diversity. Dolphins are one example. Across the world the bottlenose dolphin has developed many different ways to feed. These feeding behaviors take years to learn and are related to the variables in the area they live. Having diversity in behavior likely gives this species the capacity to withstand problems in their environment. Therefore reducing that diversity in behavior is something that is concerning. Bottlenose dolphins in the Florida Keys use two unique feeding behaviors, mud plume and mud ring feeding that are under threat of extinction. The shallow waters of this region may change considerably from climate change factors, such as sea level rise and increasing water temperature. This project will document the importance of these feeding behaviors to the population of dolphins in the region as a whole. We combine historical and novel field data to investigate two foraging cultures of dolphins in the shallow waters of Florida Bay—the mud-ring and mud-plume feeding. The first goal is to reveal how each foraging tactic functions, and then quantify their implications for individual dolphins and their population. The second goal is to use these insights to design computer simulations to evaluate how long these local cultural tactics can persist in face of the predicted human-induced ocean warming and sea level rising. Working with models and data, we will be able to predict future outcomes to this species in lower Florida in overall health and behavioral diversity.

Funded By

The spread of maladaptive foraging behavior among dolphins

PIs: Mauricio Cantor, Katie McHugh, Randall Wells
Collaborators: Sonja Wild
Graduate students:
Kyra Bankhead

Project Summary: The population of bottlenose dolphins in Sarasota Bay, Florida, has been painstakingly monitored for over 50 years, resulting in a rich, individualized knowledge of their foraging and social behavior. This population displays a large range of foraging tactics, including ‘begging’ for food hand-outs to recreational boats and anglers. While previous studies have suggested that ‘begging’ is, at least partially, a learned behavior, the exact transmission mechanism of this maladaptive foraging behavior through the population remains poorly understood. This population is therefore an ideal subject for empirically investigating the spreading dynamics of maladaptive behaviors in wild social animals. Kyra proposes to extend these previous studies by explicitly modeling the spreading dynamics of ‘begging’ through the dolphin social network to determine whether ‘begging’ is individually learned by trial and error or socially transmitted, and whether ‘begging’ relates to the resource needs of the individuals. The specific goals of her research are to quantify (1) how dyadic (home-range overlap, genetic relatedness) and individual traits (‘begging’ frequency, sex, age) influence the dolphin social network; and (2) how much, if any, of the spreading of ‘begging’ behavior is due to dolphins learning it individually, or learning socially from their peers, mothers, or other relatives.

Funded By

The Sotalia project

Collaborative research on population and social dynamics of Guiana dolphins

Photo credit: Laboratory of Ecology and Conservation (LEC-UFPR-BRAZIL)

PIs: Camila Domit, Marcos Rossi-Santos, Mauricio Cantor
Graduate students: Stephane Maura, Daiane Marcondes, Fernanda Fecci, Estela Soares, Tania Nogueira

Project Summary: In partnership with Prof. Camila Domit from the Universidade Federal do Paraná and Prof. Marcos Rossi-Santos from the Universidade Federal do Recôncavo da Bahia, the LABIRINTO has been involved in several research projects focused on Guiana dolphins (Sotalia guianensis), a small cetacean endemic to the coastal waters of the southwestern Atlantic Ocean. Through the hard work of several talented masters and PhD students, we have been investigating several aspects of the behavior, ecology and conservation of the species in two locations in Brazil, the Paranaguá Estuarine Complex and in the Todos os Santos Bay. We combine multiple sources of empirical data, such as photo-identification, drone-based tracking, acoustic recording to investigate spatial distribution, population and social dynamics, acoustic communication, parental care behavior, and then related these to the growing anthropogenic disturbances in these areas.

Funded By

The sperm whale project

Population status, distribution, behavior, and exposure to anthropogenic disturbances off the Galápagos Islands

PIs: Hal Whitehead, Ana Eguiguren
Collaborators: Mauricio Cantor, Luke Rendell, Taylor Hersh and many others

Project Summary: In contribution to the long-term monitoring of the sperm whales led by Hal Whitehead of Dalhousie University (Canada), the research vessel Balaena returned to the Galápagos for more research cruises, led by Ana Eguiguren (Dalhousie University). The team searches for and tracks sperm whales and other cetaceans in the deep waters (>1000 m) around the archipelago. The goals of the current research campaign are to collect behavioral and acoustic data for Ana Eguiguren’s PhD research. Ana derives tools from human musicology to explore how sperm whale communication codas are structured and the “rules” with which they are exchanged. She also investigates whether there are universal rhythmic traits in the acoustic communication of sperm whales and other deep-diving cetaceans (e.g. beaked whales) across social contexts and ocean basins. The overarching goal of the long-term monitoring is to assess the status of the different sperm whale vocal clans that use the Galápagos archipelago. The LABIRINTO will contribute by helping to collect and analyze fine-scale behavior and morphometric data from drone imagery.

Funded By

The human-wildlife cooperation project

PIs: Jessica van der Wal, Dominic Cram, Mauricio Cantor, Natalie Uomini, Claire Spottiswoode
Collaborators: The African Honeyguides Project, The SELA/PELD project, and ~ 50 scientists and practitioners, of human-wildlife cooperation

Project Summary: Conservation decision makers routinely address conflict between human interests and the protection of wildlife and ecosystems, yet challenges remain even when the interests of humans and wildlife are aligned. Humanwildlife cooperation — in which humans and free-living wild animals actively coordinate to achieve a mutually beneficial outcome — represent rare cases of active collaboration between humans and animals without domestication or training. This project has been investigating the few of the historical cases of positive interactions between fishers and cetaceans, hunters and wolves, and hunter-gatherers and honeyguide birds that are active today. The evolutionary origins of these humanwildlife interactions, as well as the causes of their current decline, remain poorly understood by both the scientific and the traditional communities that are directly involved. A large group of experienced practitioners, anthropologists, linguists, conservation scientists, and ecologists from all continents have been working together to investigate how these unique interactions function, how they vary geographically, and the threats they face, to generate specific, detailed strategies for protecting and archiving them. This large collaborative group of more than 50 scientists and practitioners now aim to investigate the likely routes through which environmental and climate changes can aggravate the loss of these rare biological phenomena.

The human-animal conflict project

Involving stakeholders to reduce the impact of lethal bather protection programs in South Africa

PIs: Shanan Atkins, Neville Pillay, Mauricio Cantor
Graduate Students: Shanan Atkins
Key collaborators: Geremy Cliff, Judy Mann-Lang

Project Summary: Through the work of Shanan Atkins, a PhD candidate I co-advise with Prof. Neville Pillay, the LABIRINTO is involved in a trans-disciplinary stakeholder engagement to find solutions to accelerate changing the use of shark nets and drumlines used to protect bathers in South Africa, because these methods have a high ecological cost — direct killing of sharks. Shanan’s work aims to design a strategy for the implementation of non-lethal alternatives to shark nets that protect bathers from the risk of shark attack at Richards Bay using multi-disciplinary, collaborative, solution-focused research. The main objectives are to identify leverage points to facilitate change of the current system of culling sharks by mapping the human-wildlife conflict pertaining to preventing shark attack at Richards Bay, exploring solutions with the stakeholders by co-producing knowledge to manage the conflict, and understanding public perceptions.

Funded By

Using point process models and Lagrangean retromodels to reveal the spatial-temporal patterns of sea turtles mortality

PIs: Camila Domit, Micon Di Dominico, Mauricio Cantor
Graduate students: Gabriel Farga Da Fonseca, Daiane Marcondes, Fernanda Fecci, Estela Soares, Tania Nogueira

Project Summary: Through the PhD research work by Gabriel Fonseca, co-advised by Prof. Camila Domit and Prof. Maikon di Domenico from the Universidade Federal do Paraná, Brazil, this project aims to evaluate the space-time variations of stranding events of five species of sea turtles obtained by the largest beach monitoring program in the world (PMP-BS) in southern and southeastern Brazil. The main goal is determining the influence of biological, health, environmental and anthropogenic factors on the occurrence, mortality and drift of sea turtles in the region. We also aim to find the hotspots of mortality through Lagrangian retro models, and to identify stranding intensity patterns, and factors that influence them. In addition, this project aims to improve the analytical approach “Point Process Models” for application in stranding modeling studies and risk assessment for marine megafauna species.

Funded By