A comprehensive study published in the journal Marine Mammal Science analysed over 60 years of recorded interactions between Southern Resident killer whales (SRKW) and porpoises in the Salish Sea. This endangered population of orcas, known for their fish-based diet, particularly Chinook salmon, has been involved in numerous incidents of porpoise harassment, leading to the deaths of many porpoises.

Possible explanations

The study proposes three main reasons for this behaviour:

Reefs are vital centres of marine biodiversity. Yet, human activities like overfishing, deep-sea mining, dredging and trawling have led to their significant decline worldwide. Hence, there is an urgent need to implement efficient restoration initiatives to restore biodiversity.

A recent study published in Frontiers in Marine Science reveals an unexpected ally in this mission: fruit trees.

The study, conducted in the Dutch Wadden Sea, involved sinking felled pear trees into the sea to reconstruct reefs and enhance local marine biodiversity. 

In an unprecedented archaeological feat, the shipwreck known as "Marausa 2," which sank off Marausa, Sicily, in the late 3rd century, has been meticulously recovered from the seabed in its entirety. This marks the first instance where a Roman ship has been raised in its complete form, as opposed to being retrieved piece by piece.