The Effects Of Human Pollution On Dolphins And Whales
Animal advocates, conservationists, and environmental activists have long known that pollution and contamination in ecosystems can become a problem for local wildlife. What’s more, contaminants tend to bioaccumulate up the food chain, meaning that as smaller animals are eaten by larger ones and so on, the levels of contamination can increase greatly. In this article, a team of researchers from universities across the United States tested stranded dolphins and whales — animals higher in the food chain — for dangerous levels of human-caused toxins, from 2012-2018. Using samples from the animals’ blubber, the scientists found dangerously high levels across species. While there was some variation by the sex, age, and location of each animal, the important finding remains: these human-caused pollutants are pervasive to the highest levels of the marine ecosystem.
For instance, with respect to bottlenose dolphins, the stranded creatures showed substantially higher average concentrations of lead, mercury, selenium, and lower average concentrations of arsenic and cadmium than samples taken from pygmy sperm whales. In female bottlenose dolphins, typical arsenic concentrations were significantly higher than for males. Additionally, dolphins that were beached in Florida showed much higher amounts of lead and mercury, and lower concentrations of iron than dolphins that stranded in North Carolina. Crucially, the scientists conclude that reducing exposure to these toxins in free-ranging dolphins and whales may lead to improvements in health and declines in stranding.
The scientists state that, in part, why these animals are useful to gauge the overall health of the oceans and their food webs is that these cetaceans (that is, dolphins and whales) are near the apex. Specifically, by studying the “top of the pyramid,” the researchers can understand how widespread and potent the toxins are down to the bottom. This study presents yet another in the mountain indicating the ill effects of human activity on the global ecosystem.
Thus, the scientists conclude, we must take further action still to minimize the negative effects of human activity on the environment collectively, and help to improve the welfare of the non-human animals that inhabit it. While not profound to climate and animal rights activists, this work nonetheless offers another crucial piece of evidence in our fight for the planet. For animal advocates, the study provides a further piece of evidence that shows just how much pollution and contamination affect animals, all the way up to the charismatic megafauna that are the stars of many conservation campaigns.