Climate change or Overfishing?

Everyday there seems to be something new that our society needs to be concerned about. Whether that be to lessen greenhouse gases emissions, carpool more often, take a bike rather than a car, and also stopping the dilemma of overfishing. Fish species respond to our overfishing, and are greatly impacted by the ever changing climate effecting the ecosystem's sustainability. Overfishing has been shown to effect coral reefs and kelp forest. According to a study from the ecosystem of the Canadian east coast reveals that the elimination of larger predatory fish can cause effect on the pelagic food web (Scheffer, Carpenter, & Young, 2005). When the larger predatory fish populations decrease, the smaller fish will increase from having competition for survival. Fish stocks need to be managed so understand the effects both the climate and fishing have on populations. According to Scheffer, Carpenter & Young (2005) many scientists believe that overfishing is a dominant force that is driving the collapse of fish stock. At the same time many believe that it is the increasing climate change that are affecting the population of fish. With both the overfishing and climate change factors many reefs have lost their ability to absorb recurrent natural disturbances (p.1621). According to a study fish population decreases when human population increases (p.1626).
The study focused mainly on parrotfish, and how the population was effected from the populations of humans. From their study they found that a decline in fish population was dependent on the species of fish. Some were able to handle the pressures of fishing, while others were struggling to keep up. The findings explain that human population density are the dominant factor in the loss of large fish and the erosion of ecosystem function.
Action against overfishing needs to be taken to help begin to reverse the damage that has been done to the marine ecosystem. This is one issue that we need to be concerned about, from the impact we have on the marine life.

Scheffer, M., Carpenter, S. & Young, B. (2005). Cascading effects of overfishing marine systems. Aquatic Ecology and Water Quality Management Group, Department of Environmental Sciences. Vol. 20, Issue 11.

Bellwood, D., Hoey, A., & Hughes, T. (2011). Human activity selectively impacts the ecosystem roles of parrotfishes on coral reefs. The Royal Society.