Over fishing - Empty Nets First Issue | Page 8

Effects of overfishing

Unsustainable fishing is the greatest threate to ocean ecosystems according to most ecologists. By removing all paraphylegic organisms from the ocean, it removes an organsim from the food web, cuasing the enitre eocystem to stop functioning normally. The most targeted fish for fishing are the bigger species, such as tuna, at the top of the food chain. This causes there to be less predators for animals that are lower in the fiid chain, and their popularion can rapidly increase. This can lad to things like huge growths of alge which kill coral reefs. Another closly tied issue is bycatch, or where marine mammals, sea birds, or turutlles, or other non target species are cuaght and killed. Overfishing also causes a hue loss in genetic, species, and eocystem biodiversity. Loss of genetic diversity makes it so a species has less of a gene pool to adapt to changin environmental conditions. Loss of species diversity

Throughout history, ocean predator prey relationships have kept jellyfish populations in check Overfishing creates more opportunity for jellyfish to feed and breed. The destruction of a fish species like salmon removes one of the jellyfish’s few predators. Without a curb on their population, jellyfish swarms start eating the eggs of smaller fish, as well as their food supply. Jellyfish also can destroy a food chain chain when they’re introduced to new ecosystems, usually through ballast water, and take over the niches of many other organisms. Humans are also helping jellyfish reproduce though providing an area for Polyps, the jellyfishes mechanism to reproduce with hard surfaces to cling to like Piers, drilling platforms and boats. This allows the jellyfish once contained to limiting breeding space to have unchecked reproduction.

Effets on Ocean Ecosystems