This video says about itself:
HUMAN NOISE DISTURBING MARINE BIRDS
29 May 2017
For the first time a study shows that cormorants can hear under water. This means they can hear – and be disturbed by – human noise: ships, construction work, etc.
From the Rare Bird Alert site:
New discovery: Cormorants can hear under water
20 June 2017
For the first time, researchers have shown that marine birds can hear under water. This offers new possibilities for the protection of marine birds in trafficked waters. Seals, whales and other marine animals can hear under water. The cormorant also has this ability, which new research from University of Southern Denmark (SDU) shows.
According to the biologists it makes good sense that a cormorant can hear under water — the environment where it finds most of its food.
About every tenth bird species — ca. 800 species — in the world hunts under water, and it may turn out that they too can also hear under water.
The sound of fish
Researchers Kirstin Anderson Hansen, Alyssa Maxwell, Ursula Siebert, Ole Næsbye Larsen and Magnus Wahlberg from the Department of Biology at University of Southern Denmark have tested the cormorant Loke’s hearing. Loke lives at SDU’s marine biology research station in the Danish town Kerteminde.
“Hearing under water must be a very useful sense for cormorants. They depend on being able to find food, even if the water is not clear, or if they live in the Arctic regions where it is dark for long periods at a time,” says Kirstin Hansen, Ph.D.
The sound of humans
1 — 4 kHz is not only the range in which fish sounds are found. There are also various human-made sounds found in this range.
“Human-made sounds can disturb the ocean’s animals to such an extent that they cannot find food or communicate with each other. It is a known problem for porpoises and seals for instance, and now it is also a potential problem for birds. It is certainly something that we should be more aware of, says Magnus Wahlberg, Associate Professor.
Human-made sounds can be everything from spinning wind turbines and ship traffic to water scooters and drilling platforms.