快猫短视频

The noisy construction of offshore wind turbines can discourage squid from hunting, which could lead to decreased squid populations and potentially decrease profits at fisheries.

Securing offshore wind turbines to the seabed involves a drilling technique called pile-driving that causes intense, continuous noise for up to three years during construction.

Previous research has shown that pile-driving may damage the hearing of and . People in the fishing industry wanted to know how this noise might affect squid populations because planned wind farms in the north-east US are set to be built near important squid fisheries, so the US Bureau of Ocean Energy Management commissioned a study.

Aran Mooney at Woods Hole Oceanographic Institution in Massachusetts and his colleagues tested how longfin inshore squid (Doryteuthis pealeii) respond to the noise while hunting their killifish prey (Fundulus heteroclitus).

The team put individual squid in a circular tank that was 1 metre in diameter. They released a killifish in the tank then observed the unfolding action. In some cases, the researchers played recorded sounds of pile-driving for 5 minutes before releasing the fish. In other cases, they turned the noise on as soon as the squid began to show hunting behaviour. In others, they didn鈥檛 play any sounds at all.

Mooney鈥檚 team found that squid didn鈥檛 catch significantly fewer fish under noise conditions. But it took them more tries to catch their prey, and they were discouraged from hunting in the first place more often.

鈥淭he squid were actually less affected than we thought they were going to be,鈥� says Mooney.

Even so, he thinks the effects might be more severe in the real world. For instance, in a confined tank, it is easy for a squid to try again if it fails to catch a fish at the first attempt, but in the wild, it is less likely to get a second chance with a particular fish.

Furthermore, it takes a squid a lot of energy to chase down their prey in open water, so failed hunts take a toll. If pile-driving noise hinders their ability to hunt even to a limited degree, it could lead to a decrease in populations around wind farms during construction. This could affect fisheries, and the marine ecosystem, because squid play important roles as both predators and prey, says Mooney. The team hopes to do fieldwork to address how big the effect might have.

Mooney says that while the noise from pile-driving alone may not have a huge impact on longfin squid populations, it could combine with other negative impacts like warming ocean waters.

鈥淚f we鈥檙e adding one more pressure to them, there鈥檚 a chance we could push fisheries to the limits,鈥� he says.