You know how annoyed you are when your next door neighbor starts mowing the lawn early in the morning? Or if you live in an apartment building, when your neighbor starts using the power drill? Sure you do. And we take that for granted, as it may be annoying, but it’s not really life threatening. It turns out that fish have pretty much the same problem, only for them it’s a life or death situation. According to a new study from the University of Exeter, ocean noise pollution decreases fish survival rates.
Motor boats and fish survival
Led by Dr. Stephen Simpson from the University of Exeter and his international team of Canadian, Australian, and British scientists, the study looked at the effects of noise pollution – namely that caused by motor boats – on young coral reef fish.
According to the findings, the noise from passing boats stresses the tiny fish out so much that their ability to flee from predators is drastically reduced. This resulted in a 50% decrease in their survival rates, as they are too stressed out to even think about escaping.
To determine this, the team tested the fish in their natural environment, as well as in a lab, with both real motor boats and recoded sounds. By collecting a bunch of damselfish, the team started their experiment.
How the experiment worked
First of all, there were four experiments – one dealt with fish in the ocean and with a real motorboat passing through, another with fish in the ocean and with recordings of motorboats, while the other two were in a controlled environment, with simulated attacks.
In all cases, the fish proved to be so stressed out by the noises that their survival rates decreased by slightly over 50%. This proved that the combination of stress and poor responses are fatal to coral reef fish.
Funded by the Natural Environment Research Council (NERC) and the ARC Centre of Excellence for Coral Reef Studies, the study may seem like it didn’t really reveal much, but it does show hope regarding the future of these animals.
Rules will most likely start to be implemented, prohibiting noisy motor boats from going near coral reefs during times of the year when the animals mate, so that the younglings don’t get eaten prematurely.
Image source: Flickr