Whale Strikes

1515 Words 6 Pages
Collision with ships is a significant cause of mortality among endangered whales. The mortality rates of the whales increase with increasing ship speed. Due to increasing ship speed, the whales are sometimes not seen prior to collision or are seen too late to be avoided. Reducing the number of collisions depends on the reduction of ship speed as whale dense areas are approached. To demonstrate, researchers have assessed the trends of ship strikes and their effect on whale populations. Between three different scientific accounts, we receive an experience of how ship strikes occur, the effect they have on whale populations, and further research to mitigate ship strikes.
In the 1900s, the whales were an abundant population located in the Pacific
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They used another population model to test the effect of ship strikes on the slowed growth of the whale population. Finally, they aimed to test the future impact of ship strikes under hypothetical mitigation scenarios. They modeled the number of ships, ship strikes and population dynamics of the whale population. A log-linear model was used to estimate the population growth and the abundance of the whales over a set period of time. A discrete-theta logistic model provided estimates of the population’s carrying capacity and the rate of growth. However, ship strikes had to be a part of the analysis in order to receive an accurate correlation between collisions and population growth. Monnahan estimated the number of observed strikes per year and imputed this data into the model. Based on this data, the future status of the whales was also estimated. Estimating the future status of blue whales depends on the number of ship strikes, which are influenced by the number of vessels and potential mitigation scenarios (Monnahan et al. 2014). One approach compared the status for hypothetical mitigation strategies and suggested that ship strikes threaten the status of the population. Another approach measured the correlation between the relative abundance of whales and current level of ship …show more content…
They emphasize the increase of ship strikes and provide ways to mitigate these collisions. The first article focuses on the relationship between ship strikes and the population trend of whales. While there seems to be a direct relationship between the two, researchers concludes that ship strikes are not the primary cause of the decrease in whale populations but rather the carrying capacity of whales in the ocean (density dependence). While the first article does not mention the speed of ships, the second article focuses on just that. Researchers demonstrate the correlation between ship speed, ship strikes and mortality rates. In both articles, the methods used are comparable. Dynamic models are used to input the estimations that result in the predicted data. The third article, analogous to the second discusses ship speed and their relation to collisions. However, the methodology is based upon previous statistics and data collected. The researchers analyze the differences in non-affected whale populations and carcasses that are struck. They also come up with explanations as to why certain whales collide with ships as opposed to

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