Essay On The Herring Population Crash

It is a little complex to actually pinpoint the main cause of the herring population crash in Prince William Sound, Alaska. Prior to the oil spill by Exxon Valdez in 1989, the herring population was increasing in a steady rate. The aftermath of the oil spill, however, resulted to very low population which was felt heavily in 1993. It has been hypothesized that the oil spill is the big factor in the reduction of fish population. After the oil spill, phytoplankton population (which are food to herrings and other small marine organisms) is greatly reduced due to reduced sunlight penetration. Oil floats in water thus preventing sunlight from entering the sea. By destroying the balance and the quantity of food for herrings, population is surely reduced.
The oil spill may also have direct mutagenic and teratogenic effects in young fish and their eggs. Egg mortalities and larval deformities have been documented in 1989 season, and along with it come usual mortalities connected to ingestion or excessive exposure to oil. Most herrings that spawned in 1989 were killed as a direct result of oil spill. Fishes are also known to switch gender through exposure to certain hormones and endocrine disruptors. Crude oil (which also contain various toxic derivatives) therefore, might have caused gender imbalance that would result to slower population growth. With smaller population and population growth along with acute exposure to oil, genetic variability is lower and hence allows for less robust immune system. The sequence of events is a good enough reason why the herring population became susceptible to the disease brought about by the virus. Recent studies also found out that caged fishes were more susceptible to the virus compared to free range ones.
A stable population of herring is very important not only economically but ecologically as well. The herring industry has been experiencing a boom during 1980s and because of the spill, up until now it hasn’t recovered. The fishing industry was affected as the virus and fungus are continually affecting the fishes, resulting to mortalities. Because of low herring population, animals such as seabirds, seals and whales have less to feed on and as such would result to reduction in their population too.
The Exxon Valdez oil spill is a disaster that is very devastating and yet another disaster is about to repeat its repercussions. The BP oil spill in Gulf of Mexico is equally as disastrous as the oil spill in 1989 and with it, comes another ecological turmoil. We are yet to see the long term effects of the 2010 oil spill to the environment but other ecological disaster is sure to occur. Fish population especially of those smaller ones will be affected heavily. Several predators such as turtles and seabirds are killed hence a population boom of highly invasive species of fishes might dominate and destroy the ecosystem. Genetic abnormalities and low diversity could also result to recurrence or disease epidemic among marine life.
Oil spills are inevitable as there is no such thing as perfect safety even in highly disciplined companies. As such, aside from the safety precautions and methods employed, a fast and reliable rescue solution should be readily available. The oil spill could have been controlled easily if the company has a method for well containment and oil recovery. The infrastructures for damage control should be ready the instant that an oil leak happens.

References

Bauman, Margaret. (2014). Demise of Herring in Prince William Sound Still a Mystery. Fishermen’s News, 70(10). Retrieved from http://www.fishermensnews.com/story/2014/10/01/features/demise-of-herring-in-prince- william-sound-still-a-mystery/280.html
Exxon Valdez Oil Spill Trustee Council. (n.d.). Pacific Herring. In: Restoring the resources injured by the Exxon Valdez oil spill and understanding environmental change in the Northern Gulf of Alaska. Retrieved March 17, 2015 from http://www.evostc.state.ak.us/index.cfm?FA=status.herring
Hershberger, P.K., Kocan, R.M., Elder, N.E., Meyers, T.R., & Winton, J.R. (1999). pizootiology of viral hemorrhagic septicemia virus in Pacific herring from the spawn-on-kelp fishery in Prince William Sound, Alaska, USA. Diseases of Aquatic Organisms, 37, 23-31.