The work of more than 60 international researchers revealed the differences between tropical and cold climates, which could decrease due to the heat rise in the oceans.
Anthropogenic climate change has had multiple consequences for life on Earth. One of these effects is the increase in global temperatures, which not only affects the quality of life for human beings, but also the ecosystems and species that inhabit the planet.
One effect of this is predation on marine fauna. A recent multidisciplinary study revealed an important fact: Predation intensifies in warmer waters, which could modify ocean communities if the temperature rise persists over time.
“Thousands of years have passed to get to this state, and all of a sudden we are increasing the temperature at a much faster rate,” said Gail Ashton, a marine biologist at the Smithsonian Environmental Research Center (SERC, United States) and lead author of the work, adding that “we really don’t know the implications of this increase.”
The research, led by scientists from the Smithsonian Institution (United States) and published in the prestigious journal Science, had the participation of more than 60 international researchers, who carried out experiments around the entire coastal zone of the American continent, covering the Pacific Ocean from Alaska to Punta Arenas and the Atlantic area, from Canada to the town of Ushuaia, in Argentina.
The work was carried out at 36 sites. In the case of Chile, experiments and measurements were made in five sites distributed along the coasts of our country. At each point, the researchers carried out different types of experiments: They placed squid remains to track predator activity, confirming that the intensity of the dominant species in warm environments was greater than in colder waters, where predation almost reached zero.
Another of the analyzes carried out in the field consisted of isolating the predated organisms, which were in direct contact with their hunters or separated through cages. It was determined that, in a climate with tropical characteristics, the biomass of the prey decreased drastically when unprotected. However, in cold areas, exposure to the dominant species did not represent a great threat to those who lived there.
“This phenomenon can occur for two non-exclusive reasons: predators may have higher metabolic rates and therefore feed faster, and/or it is due to the greater abundance and diversity of these species compared to a colder environment,” explained Dr. Nelson Valdivia, from the Center for Dynamic Research of High Latitude Marine Ecosystems (IDEAL) of the Austral University of Chile (UACh), who was in charge of the experiments in the southern zone of Chile, specifically in Punta Arenas.
“If we include the increase in temperature caused by the climate crisis, we could expect a predation intensification in areas considered colder, favoring certain species and harming others,” said Dr. Valdivia. However, he stressed that multiple hypotheses are being considered about what could happen in future scenarios.
Check the study here.