Forests with Healthy Wildlife Populations Store Four Times More Carbon

Tropical ecosystems, rich in animal biodiversity that aids in seed dispersal, can sequester carbon at rates up to four times higher than fragmented forests lacking these animals or where their movements are limited.

“This underscores the connection between the loss of animal biodiversity and the processes that intensify climate change,” explains Evan Fricke from the Massachusetts Institute of Technology. “We’ve lost the potential for tropical forest regeneration.”

While animals only store a fraction of the carbon in their environment, their activities significantly influence ecosystem carbon dynamics. Notably, species such as monkeys, birds, and rodents play a crucial role in dispersing a wide variety of seeds.

Fricke mentions that “linking this to a prolonged process like carbon capture across landscapes proved quite challenging.”

Fricke and his team examined over 3,000 plots in tropical forests where trees are returning and successfully reabsorbing carbon following disturbances. They then assessed the degree of movement and diversity disruption of seed-dispersing animals in each plot, with findings influenced by forest fragmentation and data from monitored animals.

They discovered that increased disruption in seed disperser movement correlated with lower rates of carbon accumulation. The forests with the most disturbed animal behaviors grew four times faster than those with minimal disruption.

On average, disturbances in animal diversity and movement patterns that disperse seeds halved the carbon accumulation potential of affected plots. This indicates that such disruptions had a more detrimental impact than other factors inhibiting tree regrowth, such as fires and livestock grazing.

In contrast, forests experiencing the least disruption sequestered carbon more rapidly than monoculture wood farms. “Natural growth enhanced by animal activity presents a cost-effective and biodiversity-friendly recovery method,” states Fricke.

Earlier ecological models indicated that seed dispersers might significantly influence carbon storage; however, this study further elucidates the critical role these animals play, according to Oswald Schmitz from Yale University. “It highlights their importance now and into the future.”