New research has finally demonstrated what many marine biologists suspected, but had never before seen: fish migrating through the deep sea.
The study, published last month in the Journal of Animal Ecology, used analysis of deep-sea photographs to show a regular increase in the number of fish in particular months, suggesting seasonal migrations.
Tracking fish in the deep sea is challenging. They are sparsely distributed, the water is nearly devoid of sunlight and the monitoring equipment has to withstand enormous pressure.
The study used photographs taken by the Deep-ocean Environmental Long-term Observatory System (DELOS), two observatories on the sea bed, 1,400m below the surface, off the coast of Angola.
The researchers analyzed 12,703 photographs — only 502 of which had actually managed to capture a fish — taken over seven-and-a-half years, and found that each year, in late November and June, there was a spike in the number of fish.
“It is certainly not unprecedented, but it has never really been demonstrated,” said Rosanna Milligan, an assistant professor at Nova Southeastern University in Florida and the lead author on the paper. “That is what we were able to do with this study.”
“Even after all these years, one of my favorite parts of being a scientist is when you do those first graphs of your results and start to see something emerging from the data,” said David Bailey, a senior lecturer at the University of Glasgow and a coauthor on the paper.
“That’s one of the greatest thrills of the whole scientific endeavor. It was really, really amazing,” he said.
Even with this new discovery, Milligan and Bailey still say there is a lot they do not know.
“The natural thing to do is to find out where the fish are coming from and going to when they move around,” Bailey said. “What is going on? What does it mean and what are the fish doing?”
Little is known about the behavior of any of the fish photographed.
Grenadiers, a family of fish seen in more than 100 of the DELOS photos, have long tails that might allow them to move great distances at low speed — but despite being a relatively common deep-sea fish, little information exists on how far they can swim.
A 1992 paper, for instance, put acoustic tracking devices in bait and fed them to grenadiers, but the devices only tracked the fish up to 1km away.
Milligan said the fish might be migrating to follow dying organisms on the surface.
Plankton blooms off the coast of West Africa every year four months before the deep-sea fish migrate into the area.
Given that the deep sea is dependent on life at the surface that dies and sinks to the bottom, it is possible that other animals could be gathering to take advantage of the dying plankton, and the deep-sea fish migrate to eat those.
“We just have no idea how these things act,” said Tim O’Hara, a researcher and senior curator of marine zoology at Museums Victoria in Australia, who was not involved in the research. “We are literally groping in the dark. It’s kilometers down in the ocean and we get these tiny bits of information from one or two locations and we’re trying to put together a big picture.”
Milligan and Bailey said they hope this discovery encourages other researchers to look for similar patterns in the deep oceans.
“Maybe if we had more of this level of surveillance in other places, we would find fish migrations in all kinds of places,” Bailey said. “It’s just that [Angola] is where we happened to be observing in this level of detail for this amount of time? This could be happening all over the place.”
Kehinde Sanni spends his days smoothing out dents and repainting scratched bumpers in a modest autobody shop in Lagos. He has never left Nigeria, yet he speaks glowingly of Burkina Faso military leader Ibrahim Traore. “Nigeria needs someone like Ibrahim Traore of Burkina Faso. He is doing well for his country,” Sanni said. His admiration is shaped by a steady stream of viral videos, memes and social media posts — many misleading or outright false — portraying Traore as a fearless reformer who defied Western powers and reclaimed his country’s dignity. The Burkinabe strongman swept into power following a coup in September 2022
‘FRAGMENTING’: British politics have for a long time been dominated by the Labor Party and the Tories, but polls suggest that Reform now poses a significant challenge Hard-right upstarts Reform UK snatched a parliamentary seat from British Prime Minister Keir Starmer’s Labor Party yesterday in local elections that dealt a blow to the UK’s two establishment parties. Reform, led by anti-immigrant firebrand Nigel Farage, won the by-election in Runcorn and Helsby in northwest England by just six votes, as it picked up gains in other localities, including one mayoralty. The group’s strong showing continues momentum it built up at last year’s general election and appears to confirm a trend that the UK is entering an era of multi-party politics. “For the movement, for the party it’s a very, very big
ENTERTAINMENT: Rio officials have a history of organizing massive concerts on Copacabana Beach, with Madonna’s show drawing about 1.6 million fans last year Lady Gaga on Saturday night gave a free concert in front of 2 million fans who poured onto Copacabana Beach in Rio de Janeiro for the biggest show of her career. “Tonight, we’re making history... Thank you for making history with me,” Lady Gaga told a screaming crowd. The Mother Monster, as she is known, started the show at about 10:10pm local time with her 2011 song Bloody Mary. Cries of joy rose from the tightly packed fans who sang and danced shoulder-to-shoulder on the vast stretch of sand. Concert organizers said 2.1 million people attended the show. Lady Gaga
SUPPORT: The Australian prime minister promised to back Kyiv against Russia’s invasion, saying: ‘That’s my government’s position. It was yesterday. It still is’ Left-leaning Australian Prime Minister Anthony Albanese yesterday basked in his landslide election win, promising a “disciplined, orderly” government to confront cost-of-living pain and tariff turmoil. People clapped as the 62-year-old and his fiancee, Jodie Haydon, who visited his old inner Sydney haunt, Cafe Italia, surrounded by a crowd of jostling photographers and journalists. Albanese’s Labor Party is on course to win at least 83 seats in the 150-member parliament, partial results showed. Opposition leader Peter Dutton’s conservative Liberal-National coalition had just 38 seats, and other parties 12. Another 17 seats were still in doubt. “We will be a disciplined, orderly
RSS