Final answer:
A fisherman would feel devastated at the potential extinction of indigenous species in Laguna de Bay due to its impact on marine ecosystems and local communities, highlighting the need for sustainable fishing practices and government regulations.
Step-by-step explanation:
As a fisherman witnessing potential extinction of indigenous species in Laguna de Bay, I would likely feel devastated and concerned. The loss of these species due to overfishing and environmental changes leads to a radical restructuring of the marine ecosystem. This ecosystem collapse has severe repercussions, not only for the biodiversity but also for the local communities that rely on these species for livelihood and as an affordable protein source. Additionally, it poses a risk of losing entire aquatic systems as food sources.
This scenario is not unlike the plight faced by Lake Victoria due to the introduction of the Nile perch, which resulted in the extirpation of many cichlid species. As a result, the once-rich diversity was greatly diminished. The government's role in regulating fishing becomes crucial to achieve sustainability and to protect the future availability of these common goods for both the environment and human use.