UPDATE (11:45 PST): The manta was not pregnant at the time of capture, no foetus was found during the necropsy. 

When photos of this giant oceanic manta ray surfaced last week, there was some initial speculation that they might be fake. But we're sad to report that scientists at Manta Trust and the Marine Megafauna Foundation have confirmed the images are real. The manta (Manta birostris), which tipped the scales at an astounding 1,000 kilos (2,200 lbs), was accidentally caught by fishermen off the coast of Caleta la Cruz. Despite rumour that the ray measured 11 metres (36ft) across, it's more likely that it was 5 to 7 metres (the largest documented was about 7m). 

"Oceanic manta rays are increasingly threatened in Peru," explains Manta Trust. "This is particularly worrying, because our collaborative research project with Planeta Océano and WildAid indicates that these waters house one of the world's largest populations of oceanic manta rays." It's a harrowing sight, but there is an important lesson here: bycatch is a big problem – and a tricky one. 

"If this was indeed an incidental capture, then this case truly underscores the brutal realities of the negative impacts of bycatch," says shark biologist Dr Austin Gallagher, whose work explores the vulnerability of elasmobranchs (sharks, skates and rays) to fisheries.

To make matters worse, mantas only birth one pup per litter, and it takes a female 8 to 10 years to mature. "Bycatch is the collateral damage of fishing," he adds. "It is most destructive when the species in question is highly vulnerable due to either low reproductive rates (few offspring, slow maturity), low survival rates from capture, or both."

Manta Trust and their colleagues are working to better understand the movements of these giants – many of which are pregant females – so they can help (quite literally) steer fisherman in the right direction. "By assessing landings and conducting on-board observations, we discovered that manta ray distribution in Peru coincides with four important fishery areas, leading to more incidental bycatch," explains Planeta Océano founder Kerstin Forsberg. 

"But there is hope," adds Manta Trust. "There is still much work to be done, but [we hope] that with the growing support from [and education of] the fishing community, and backing by the Peruvian government, sights like this will become a thing of the past."

For more about Manta Trust, and their work, check out this episode of "Little Adventures, Big Planet":

Top header image: NOAA's National Ocean Service/Flickr