Article: Inducing Seed Dispersal by Generalist Frugivores: A New Technique to Overcome Dispersal Limitation in Restoration by Silva and colleagues (2020)
Background: Forest restoration efforts rely on the ability to spread seeds of native trees throughout a degraded environment. However, many challenges exist in developing effective techniques, such as seed predation, climate and terrain factors, and seed vector limitations. In healthy ecosystems, frugivores (i.e., animals that consume fruit) function as seed vectors by eating the fruits of native trees and spreading the seeds around the landscape by excretion. In degraded forests, there are simply not enough seeds nor frugivores to spread them, resulting in a lack of seed dispersal and a major hindrance of reforestation efforts. In Southern Brazil, Silva and colleagues studied a low-cost method, termed Induced Seed Dispersal, to maximize the ability of even small populations of frugivores to restore their own habitat.
Methods: Silva and colleagues placed two feeders at an active rainforest restoration site and loaded them with fruits containing 1500 seeds per week for one year. Both fruits from the forest, as well as offerings such as bananas, papayas, and avocados were used to entice frugivores to the feeders. Trail cameras at both sites allowed for different species of frugivores to be identified and the amount of fruit consumed by each to be determined.
Findings: After reviewing the trail camera footage, over 24 species were identified that ate from the feeders, ranging from bats and toucans, to foxes, opossums and marmosets. It was estimated that 604 seeds per hectare per month were spread over the course of the study by the frugivores. For reference, a hectare is about the size of a soccer field.
Conclusions: Induced Seed Dispersal can be tailored to fit any environment where frugivores are present, including both temperate and tropical forests. While the method is not a singular solution to reforestation efforts, it helps solve a key issue and can be highly effective as part of a large scale integrative restoration plan. Due to its low cost and ease of implementation, Induced Seed Dispersal shines in small scale restoration projects that can be carried out by private landowners, citizen scientists, or students. Thus, Induced Seed Dispersal is not only a promising tool for restoration, but it can also connect, engage, and educate local communities.
Figure: Trail camera images of frugivores visiting both feeding sites.
Reference:
Silva, Wesley R., et al. "Inducing seed dispersal by generalist frugivores: A new technique to overcome dispersal limitation in restoration." Journal of Applied Ecology 57.12 (2020): 2340-2348.
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