14.01.2022 – Oceanic washing machine
January 19, 2022
27.01.2022 – Understanding interactions
February 3, 2022
If feeding situations were organised events by our oceans, they’d likely have a good turnout. This is particularly true when large schools of fatty, nutritious fish like Atlantic mackerel (Scomber scombrus) or Atlantic horse mackerel (Trachurus trachurus) are in the picture. The commotion of one predator species in pursuit of such schools often attracts many others…and there’s enough to go around for everyone.
Today our crew was completely taken by surprise by such an epic situation. Despite the curtain of rain impending the visibility from the coastline, our spotter managed to locate a pod of Atlantic spotted dolphins (Stenella frontalis) and our zodiac, Stenella, dashed to the area. The dolphins were hastily heading for Funchal before suddenly pausing their travels to feed on an enormous school of Horse mackerel.
Aboard the Ribeira Brava arrived at the scene, everyone could already see several Yellow-legged gulls (Larus michahellis) flocking to the area and following the dolphins, who were already leaping in pursuit of the fish. We had already been informed that spotted dolphins were in the area by the Stenella crew but were welcomed by a large group of hungry Short-beaked common dolphins (Delphinus delphis), who must have arrived simultaneously with us and threw in a short ride at our bow before turning their attention to the chase.
It was magnificent to watch the dolphins coordinate so cleverly and gather the fish at the surface into a tight group, so that we could watch a few terrified mackerel panicking at the surface. The school of fish scrambled towards the hull of the Ribeira Brava to at least escape the airborne attacks of the seagulls, who were now competing with Little shearwaters (Puffinus assimilis) to snatch their prey at the surface….but the school couldn’t escape the strategic attacks of the dolphins.
Spectacles like these belong to my favourite sightings at sea and are undeniable proof of how important these large schools of prey are. Sadly, mackerel populations in the Atlantic Ocean are currently experiencing a serious decline due to overfishing. Further exploitation of these vital species will affect predator populations and make such feeding events a rarer spectacle.
By Paula Thake
Sightings of the day
Ribeira Brava
14:30 Atlantic spotted dolphins, Short-beaked common dolphins
Stenella
15:00 Atlantic spotted dolphins
