Our zodiac drove out onto a perfectly flat ocean today and the warm rays of sunshine lighting up the surface of the Atlantic almost made it feel like a summer’s day. After stopping to admire a raft of resting Cory’s shearwaters (Calonectris borealis) and a Portuguese Man O’War (Physalis physalis) with the remainders of its last fishy meal still dangling from its tentacles, our boat was soon warmly greeted by a pod of Short-beaked common dolphins (Delphinus delphis).
These gorgeous dolphins are usually seen hunting during the winter season but, when they aren’t hunting, they usually dash towards our boat for a bow-ride and this is exactly what they did today. The pod was dispersed into smaller subgroups, with one even containing a little cheeky calf and a melanistic dolphin, who had lost his characteristic yellow hourglass pattern due to the mutation but remained equally beautiful. Sandwiched between the scattered groups of common dolphins was a compact group of shy Striped dolphins (Stenella coeruleoalba) who unfortunately didn’t show as much interest in the boat as their neighbours and immediately darted in the opposite direction as our boat approached.
For now these two beautiful dolphin species enjoy a wide distribution in the Atlantic Ocean but their populations are nonetheless severely threatened through irresponsible fishing practices. In the Mediterranean, the overfishing of certain fish species has lead to an extreme depletion in the prey available for common dolphins and has resulted in a dramatic decrease in their population. Their relatively narrow prey spectrum has also made them victims overfishing of Atlantic mackerel (Scomber scombrus) in the Atlantic Ocean, a practice that affects all the large marine predators of the Atlantic and has caused unprecedented trophic shifts with consequences that are difficult to predict. Super trawlers are also emptying the oceans with their enormous nets and often scoop up pods of dolphins, particularly common and striped dolphins, who rarely survive this extremely stressful experience.
We always make sure to include such information on board since honest whale-watching requires addressing both sides of the story; the positive and the negative. Dolphins are the perfect ambassadors to communicate this urgency to protect our oceans because they clearly show us what future generations will miss if we continue to ignorantly overexploit our oceans. It’s up to us to make a change.
By Paula Thake
Sightings of the day
10:00 Short-beaked common dolphins, Striped dolphins