- Suckermouth catfish were spotted adopting strange formation in Costa Rica
- They amazed passersby who watched them migrate along the Pacuare River
- Scientist says the ‘uncommon behaviour’ was adopted for reproduction
This is the bizarre moment a school of fish migrated in a linear clump as they snaked through water in a very orderly fashion.
Footage shows the suckermouth catfish swimming along the edge of the Pacuare River in Costa Rica to the amazement of passersby.
Resembling a regimented line of ants, they adopted the strange formation while performing their annual upstream migration.
This is the bizarre moment a school of fish in a river in Costa Rica migrated in a linear clump as they snaked through water in a very orderly fashion
Footage shows the suckermouth catfish swimming along the edge of the Pacuare River in Costa Rica to the amazement of passersby
Wildlife expert Luis Antonio Mogli Picado, who recorded the footage, says this is the first time he has seen the fish adopt this formation in the 20 years he has lived there.
‘I have seen these fish migrate every year,’ he said. ‘I always watch them two months before they migrate upstream, but I have never seen them swim in a row like this.’
National University of Costa Rica researcher Rigoberto Viquez explained the phenomenon is rarely adopted during migration.
‘When this phenomenon occurs it is for reproduction rather than seeking refuge or food,’ she said. ‘It is an uncommon migratory behaviour.’
Known locally as ‘rock-suckers’ because they feed on moss that grows on large stones and boulders, they are about 12 centimetres long when fully grown.
The clip comes days after a UK mother landed an enormous catch in Australia.
Resembling a regimented line of ants, they adopted the strange formation while performing their annual upstream migration
The 68-year-old tourist hooked a monster 62 kilogram fish – measuring longer than her own body – during a fishing trip with her son.
UK pensioner Sue Elcock was visiting her son Simon and his wife Michelle in Perth, Western Australia last week when she wrangled the 162cm bass.
As soon as she felt a tug on her line, Ms Elcock said she knew it was a ‘fair-sized fish’.