How does overfishing of species like tuna cod and sardines can affect the kelp population of the bay ecosystem?

Overfishing species like tuna, cod, and sardines disrupts the balance of the bay ecosystem by removing key predators and competitors that help maintain the population of herbivores, such as sea urchins. With fewer predators to control their numbers, sea urchins can proliferate and overgraze on kelp, leading to significant declines in kelp forests. These kelp forests are crucial for providing habitat and food for various marine species, and their loss can further destabilize the ecosystem. Consequently, overfishing can initiate a cascade of ecological changes that ultimately harm biodiversity and the overall health of the bay.