Humpback whale songs recorded off the coast of New York

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The song of humpback whales as they swim off the coast of New York has been recorded for the first time by a series of underwater microphones, scientists claim.

The discovery involved searching thousands of hours of audio data for whale call signs, explains Julia Zeh, a doctoral student at Syracuse University in New York who completed the work while a student at Columbia.

Underwater sound recording equipment, located on the waters off New York, helped them discover that the whales had been swimming in the New York Bright.

They were there during the winter and spring, when the whales are normally in the warmer Caribbean for the mating season, Zeh explains.

The team can’t say exactly why there is an increase in humpback whale numbers during the winter months in New York, but predict that they either turn the area into a mating area, or that young males are left behind because they aren’t old enough to breed.

In this photo, taken from a boat in New York Harbor in December 2020, a humpback whale appears near the Statue of Liberty.  This was eight years after the shots were taken, so the two aren't linked, but researchers say there's an increasing number of sightings

In this photo, taken from a boat in New York Harbor in December 2020, a humpback whale appears near the Statue of Liberty. This was eight years after the footage was taken, so the two aren’t linked, but researchers say there’s an increasing number of sightings

Humpback Whale Populations and Their Threats

Humpback whales live in oceans around the world.

They travel incredible distances every year and have one of the longest migrations of any mammal.

Some populations swim 5,000 miles from tropical breeding grounds to colder, more abundant feeding grounds.

Therefore, according to the National Oceanic and Atmospheric Administration (NOAA), it is difficult to estimate population size.

Of the 14 different populations, 12 are estimated to have more than 2,000 humpback whales each and two are estimated to have fewer than 2,000.

Threats to humpback whales include a decline in foods such as krill due to a combination of climate change and industrial-scale fishing.

Humpback whales can become entangled in many different types of fishing gear, including moorings, traps, pots, or gillnets.

Once entangled and able to move the fishing gear, the whale can tow and swim long distances with attached fishing gear, ultimately resulting in fatigue, reduced feeding capacity, or serious injury.

As part of the researcher, the team analyzed 6,305 hours of audio recordings captured by microphones on the seafloor 70 miles south of Long Island.

They were captured between 2009 and 2009, but the data has only recently been studied specifically for signs of humpback whales in the New York Bight.

“Suddenly there in the background, it starts out a little quiet and then gets louder. I was so excited to hear it!’ Zeh told CBS about the discovery in an interview.

It’s unusual to hear humpback whales singing so far north, as well as outside their normal mating season during fall and winter, when they’re found in warmer, Caribbean climates, the study authors explained.

This study took advantage of acoustic recorders sitting on the ocean floor year-round, providing the opportunity to detect whales even if they might not be seen during visual surveys.

The study authors say having alternative methods of whale watching could support future conservation efforts and protect the giant bus-sized marine mammals as they venture into one of the busiest waterways in the world.

“The more we know about how and when whales use these areas, the more informed decisions we can make about how to better protect them,” said Howard Rosenbaum of the Wildlife Conservation Society in New York.

Whales venturing into New York waters spend most of their year in the North Atlantic, but migrate south for the winter, sleeping in the Caribbean where they sing and breed in tropical waters.

New York’s waters were thought to be just a passageway for the migration, but recent sightings and these audio recordings show they spend more of their year in the colder waters.

Researchers predict that this may be due in part to climate change, with the whales adapting to warming waterways.

There has been an increase in the number of sightings of humpback whales in the mid-Atlantic, researchers say.

The New York Department of Environmental Conservation spotted the creatures and recorded the singing of humpback whales in 2017 and 2018 in the same region.

This new study uses recordings first taken in 2008, but only recently analyzed due to difficulties in sifting through the thousands of hours of data.

New York State monitors whale activity in an approximately 17,000-square-mile zone that extends from Long Island to the outer continental shelf.

The team can't say exactly why there is an increase in humpback whale numbers during the winter months in New York, but predict that they are either turning the area into a mating area, or that young males are left behind because they are not old enough to breed.

The team can’t say exactly why there is an increase in humpback whale numbers during the winter months in New York, but predict that they are either turning the area into a mating area, or that young males are left behind because they are not old enough to breed.

“The traditional paradigm for humpback whale song is that it’s produced by males in breeding grounds for these whales around the Caribbean,” Zeh said.

“So it’s not something you necessarily expect to find further north.”

To go through the hours of audio, they created an algorithm that isolated the telltale signs of the humpback whale’s song, recorded within 70 miles of Long Island.

They found they sang in the winter and spring of 2008, making it the earliest known evidence of this behavior in the New York Bight.

“The most surprising thing that we recorded it in the winter, when they traditionally thought they had already migrated to their equatorial breeding grounds,” Zeh said.

The discovery involved searching thousands of hours of audio data for whale call signs, explains Julia Zeh, a doctoral student at Syracuse University in New York who completed the work while a student at Columbia.

The discovery involved searching thousands of hours of audio data for whale call signs, explains Julia Zeh, a doctoral student at Syracuse University in New York who completed the work while a student at Columbia.

One reason for this unexpected behavior could be evidence that the younger, immature males don’t go all the way south, although the why remains unknown.

New York DEC’s Stephanie Rekemeyer said it could simply be that they are not old enough to mate, so don’t bother making the trip south.

The other explanation is that they could turn the New York Bight into a mating ground. This theory comes from the increase in sightings and recordings in recent months, especially in winter when they would normally mate.

The findings are published in the journal Science of marine mammals.

WHALE SONG EXPLAINED

For a long time it was believed that whales only sang to mate.

But some experts suggest the songs also help the mammals explore their environment.

Researchers have recorded humpback whales changing their calls when they move to new pastures to match the songs of others around them.

Learning these songs can help whales locate and group each other better in unfamiliar waters.

Researchers have recorded humpback whales changing their calls when they move to new pastures to match the songs of others around them (file photo)

Researchers have recorded humpback whales changing their calls when they move to new pastures to match the songs of others around them (file photo)

It’s difficult for scientists to study how whales sing, as the shy creatures are notoriously difficult to observe and each species has a different voice.

Humpback whales sing using folds in the voice box that vibrate at low frequencies when air is pushed over it.

It has been suggested that they have special air sacs next to these vocal cords that connect to the lungs.

This allows the whales to pass air between their lungs, sacs and vocal cords without losing any of their precious air supply.

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