Mauriel Rodriguez Curras
Humans are exceedingly becoming the primary drivers of global change by altering landscapes, connectivity, and climate processes. As a consequence, many species on Earth have either gone extinct or are increasingly becoming vulnerable to extinction, while others are thriving. It is my primary interest – and the reason why I am pursuing a PhD – to understand how humans impact species distributions and interactions over multiple spatial and temporal scales. I am also fascinated by the behavioral strategies that species employ to co-occur with their predators and competitors, and how humans alter or mediate those interactions. My master’s – completed in December 2019 – and now my PhD, focus on addressing these questions through the lens of carnivore community interactions.
Laguna Blanca National Park, Argentina
Carnivores co-occur by minimizing overlap in their critical niche axes: space, time, and resources. However, we currently lack rules for how carnivore communities operate in human-dominated landscapes. During my master’s, we simultaneously quantified niche overlap in a simple carnivore community—an apex carnivore (Puma concolor), a dominant mesocarnivore (Lycalopex culpaeus), and a subordinate small carnivore (Lycalopex griseus)—co-occurring in a human landscape featuring pastoralists and semidomestic carnivores (i.e., dogs, Canis familiaris). We found support that interference competition was the driver of carnivore space use – smaller species avoided the space use of their larger competitors. Meanwhile, humans and dogs were strictly diurnal, whereas the native carnivore community was nocturnal and exhibited high temporal overlap. Dietary overlap was high among the native carnivores, but dogs were trophically decoupled, largely because they consumed primarily human foods. Our results show that in landscapes with evident human presence, temporal and dietary partitioning among native carnivores can be limited, leaving space as the most important axis to be partitioned among carnivores. See Rodriguez Curras et al., 2021 Behav. Ecol. and Rodriguez Curras et al., 2022 Am. Nat.
Isle Royale National Park, US
Carnivore restoration has been promoted as an effective management tool to re-establish community interactions and lost functional roles. However, the strength and extent to which interactions are restored – particularly in novel, human landscapes – is often unclear, especially for how returning large carnivores affect competitive interactions within carnivore communities. Throughout my dissertation, I aim to expand the fatal attraction hypothesis – predicting increased conflict associated with scavenging – to account for human effects. I will use a variety of highly interdisciplinary field methods and statistical approaches to address these questions. Results from my dissertation have shown that the predicted – and often desired – consequences of large carnivore reintroductions or natural recolonizations may not be permanent due to the transitory dynamics of large carnivores and the impacts of humans, especially due to resource subsidies. My research will be broadly applicable to conservation and management and calls into question the efficacy of carnivore-driven restoration efforts in the Anthropocene.