Landscapes of fear, and the large carnivores they feature, important in African ecosystems

March 07, 2019

A new study focused on Mozambique's Gorongosa National Park, where entire populations of large-mammal predators were nearly extinguished during the Mozambican Civil War, illustrates how the loss of an ecosystem's top carnivores can have far-reaching consequences for prey and plant populations, turning "landscapes of fear" into "landscapes of fearlessness" in which emboldened herbivores graze and suppress plants. While the results of this study illustrate the cascading ecosystem impacts of human-mediated predator extinction, they also show that carnivore restoration in these areas could help reverse any ill effects of human activity, the authors say. The Mozambican Civil War (1977-1992) ravaged the populations of large mammals throughout Gorongosa and resulted in declines greater than 90% across all monitored species. To date, the region remains nearly devoid of carnivorous predators like leopards, wild dogs and hyenas. Apex predators, however, play a central role in defining an ecosystem through trophic cascades - an ecological concept that describes the complex and often indirect interactions between all members of an ecosystem's food web. One way in which predators can reduce prey abundance is by creating landscapes of fear, resource-rich yet risky habitats that prey tend to avoid to reduce their chances of being eaten. By changing the behavior of herbivores in this way, predators can create habitats where certain food plants can thrive. However, in the absence of carnivores, these once-risky habitats could become landscapes of fearlessness, where emboldened herbivores graze and suppress plant abundance. According to the authors the war-ravaged animal populations of Gorongosa provide a valuable opportunity to evaluate trophic cascades in large mammals that are otherwise difficult to study. Justine Atkins and colleagues observed the behavior of the bushbuck, an antelope that largely keeps to the cover of trees to avoid predators. However, in Gorongosa by at least 2002, Atkins et al. noticed a shift in its behavior; GPS-collared bushbuck, recognizing predators were less abundant, ventured into the treeless floodplain to feed - a decision that would otherwise be dangerous. Critically, the authors demonstrated that these shifts were reversible. By mimicking the presence of predators through recorded sounds and urine, fearless bushbuck became fearful and shifted their behavior accordingly, despite the decades-long absence of predators.

American Association for the Advancement of Science

Related Behavior Articles from Brightsurf:

Variety in the migratory behavior of blackcaps
The birds have variable migration strategies.

Fishing for a theory of emergent behavior
Researchers at the University of Tsukuba quantified the collective action of small schools of fish using information theory.

How synaptic changes translate to behavior changes
Learning changes behavior by altering many connections between brain cells in a variety of ways all at the same time, according to a study of sea slugs recently published in JNeurosci.

I won't have what he's having: The brain and socially motivated behavior
Monkeys devalue rewards when they anticipate that another monkey will get them instead.

Unlocking animal behavior through motion
Using physics to study different types of animal motion, such as burrowing worms or flying flocks, can reveal how animals behave in different settings.

AI to help monitor behavior
Algorithms based on artificial intelligence do better at supporting educational and clinical decision-making, according to a new study.

Increasing opportunities for sustainable behavior
To mitigate climate change and safeguard ecosystems, we need to make drastic changes in our consumption and transport behaviors.

Predicting a protein's behavior from its appearance
Researchers at EPFL have developed a new way to predict a protein's interactions with other proteins and biomolecules, and its biochemical activity, merely by observing its surface.

Spirituality affects the behavior of mortgagers
According to Olga Miroshnichenko, a Sc.D in Economics, and a Professor at the Department of Economics and Finance, Tyumen State University, morals affect the thinking of mortgage payers and help them avoid past due payments.

Asking if behavior can be changed on climate crisis
One of the more complex problems facing social psychologists today is whether any intervention can move people to change their behavior about climate change and protecting the environment for the sake of future generations.

Read More: Behavior News and Behavior Current Events is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to