Autumn in the Atlantic

Autumn in the Atlantic

By Jax Bath

March marks the beginning of autumn, with a coolness setting into the mornings and the sun dipping below the horizon ever earlier. March also happens to be one of my favourite months at sea. Like the leaves falling on land, autumn in the Atlantic is marked by certain changes that make the onset of winter apparent. Autumn is the time of year when pelagic seabirds reappear on our tours, the cheeky Sub Antarctic Skua takes their place in the sky parallel to every boat that leaves the harbour and, most of all, it is the beginning of the sardine run.

Setting out to sea at this time of year comes with a certain type of anticipation. The ocean might be quiet and yield no mega fauna at all, but, more than any other time of year, there is also a chance to happen upon the best the ocean has to offer. At this time of year, sardines begin to make the annual migration from the cool waters of the west towards the warmer Indian Ocean. Surprisingly little is known about this natural phenomenon, but it is often claimed to be the largest shoal on earth as billions of these little fish move east. It is believed that some spawning takes place on the Agulhas bank, and the abundance of adult fish moving through attracts a host of predators that will gauge themselves on these oily fish.

From a wildlife watching perspective, what you’re really hoping to find out at sea is what we call a bait ball. This is when a school of fish moves together, staying as close as possible to one another in the hopes of surviving predation. The bait ball may give rise to the commonly used phrased “packed like sardines” and these little fish know all too well the importance of this. Unfortunately for them, their predators have learned to work in unison to divide them up and create a feeding frenzy that Blue Planet compared to burning water. This is what every wildlife watcher wishes to experience out at sea, the dance between predator and prey as birds provide an aerial attack while seals, sharks, whales and dolphins try to scatter the shoal from below. The result is chaos at the surface, with waters turning white as the animals churn and hunt below.

Click on the newspaper below to read more (see page 20).