Aug 2

A new study has identified the 20 most important regions of the world’s oceans to marine mammal conservation. However, the study, published in the Proceedings of the National Academy of Sciences, also revealed that most of these areas are under pressure from human impacts such as pollution and shipping.

Photo of short-finned pilot whale

Short-finned pilot whale

Marine mammal hotspots 

Sandra Pompa, an ecologist at the National Autonomous University of Mexico, led a team of scientists to try and identify which parts of the world’s oceans are most crucial for the world’s 123 marine mammal species, as well as an additional 6 freshwater mammal species, which includes freshwater seals and dolphins.

The team split the oceans up into a grid of roughly 10,000 boxes, each of a square kilometre, and examined which species lived in which boxes. The boxes were also assigned values based on whether they contained important feeding grounds or if they coincided with migration routes. 

Their results revealed nine key global conservation sites that hold 84% of marine mammal species, as well as 11 “irreplaceable” conservation sites, which contain species that are found nowhere else.

Photo of vaquita as bycatch, being hauled in by a fisherman

Vaquita as bycatch, being hauled in by a fisherman

Human impacts 

The maps were analysed alongside information on human impacts such climate change, pollution and commercial shipping. 

Seventy per cent of the most impacted areas were near a key conservation site,” said Pompa. “We are competing with [the sea mammals] in terms of shipping or ocean pollution. We want to build industry or touristic attractions and it’s their home.” 

According to the paper, the next species of marine mammal most likely to become extinct is the vaquita – a small porpoise that is endemic to the most northern part of Baja California. It is thought to number only around 250 individuals in the wild. 

The Baikal seal, also has a very small-numbered population confined to Lake Baikal in Russia. “Maybe you can think about the vaquita escaping the Gulf into somewhere else but the Baikal seal can’t. It’s a freshwater endemic mammal species. If any disruption in the lake should happen or a new sickness, they’re all packed in one lake” said Pompa.

Photo of Baikal seal

Baikal seal

The researchers said that their maps should allow conservationists to start safeguarding those areas most important to the world’s marine mammals. “Perhaps you are a government or NGO, you can use this information as a tool depending on the aim you have,” said Pompa.

Marine conservation is barely beginning. Marine mammals are great species because they represent healthy ecosystems so, if you begin to lose the species that give you a clue to a healthy ecosystem then you start with the degradation of all of the oceans. A visual projection of where is the richness, where are the endangered species, which corridors we need to protect in order to have all the species present in the world, it’s a nice start to know where to focus the effort.” 

Read the full story at the Guardian – Scientists name world’s most important marine conservation hotspots.

Read the paper published in the Proceedings of the National Academy of Sciences.

Alex Royan, ARKive Species Text Author