In-Favor of Lethal Population Management

We are focusing on the salmon populations in the pacific northwest where cormorants are predating on salmon. Pictured is East Sand Island which is a specific place where cormorant elimination is occurring.

Cormorants are not endangered, so it is okay to decreases their populations in order to try to save the salmon populations. Here is a graph of cormorant populations, it is not showing the U.S. but it does show an increase in cormorant populations. In the past, cormorants were endangered due to being hunted and poisoned by pesticides like DDT. However, this is no longer the case and their populations are now booming. Cormorants are abundant and widespread throughout the pacific northwest.

Cormorants pose a large threat to salmon populations. Salmon populations are vulnerable, so cormorant killing can be justified. Salmon populations keep decreasing, as seen in this graph, so cormorants must be killed since they play a significant role in their deaths. Cormorants eat on average 11 million salmon a year and prey on up to 17 percent of the juvenile salmon that are migrating out. By killing cormorants, salmon populations have the chance to thrive again.Here is a graph of how many juvenile salmon are eaten by cormorants.

Some people that are against killing cormorants say removing dams is a better option for salmon survival. However, removing or altering a dam would cost much more than killing the cormorants so it is not a viable option. Dams provide many benefits for communities including water supply, flood control, hydroelectricity, navigation, and reservoir recreation. Dams must stay because there are many benefits. Looking at this pie chart hydroelectricity takes up 6.7%, almost 1/10^th, of electricity generation, so removing dams would put a strain on other resources to make up for the loss in electricity which would damage the environment further, putting strain on salmon populations. Also, removing dams would take a very long time so it would not make a difference on the current problem of deteriorating salmon populations. There have also been improvements in fish passage in dams which has increased salmon survival rates so taking away dams would be pointless. Killing cormorants is the only option we have that will be effective in trying to save salmon from extinction.

 

Sources:

Mapes, Lynda V. “Killing Cormorants to save Salmon: 11,000 in Crosshairs of Controversial Program.” The Seattle Times. The Seattle Times Company, 12 Feb. 2016. Web. 18 May 2017. <http://www.seattletimes.com/seattle-news/environment/killing-one-species-intended-to-save-another-11000-birds-in-cross-hairs-of-multiyear-program/>.

 

“Double-crested Cormorant.” , Life History, All About Birds – Cornell Lab of Ornithology. N.p., n.d. Web. 18 May 2017. <https://www.allaboutbirds.org/guide/Double crested_Cormorant/lifehistory>.

 

Conca, James. “Will Removing Large Dams On The Snake River Help Salmon?” Forbes. Forbes Magazine, 01 Dec. 2016. Web. 30 May 2017. <https://www.forbes.com/sites/jamesconca/2016/11/29/will-removing-large-dams-on-the-snake-river-help-salmon/#78a8c108155b>.