miamiherald.com

Deep water whale seen swimming up shallow river in Ireland, photos show. ‘Rare event’

A sperm whale was recently seen swimming in a shallow estuary in Ireland — a rare occurrence that worried conservationists. Fortunately, the large creature “lived to tell the tale.”

The marine mammal — an infrequent visitor to the shores of the Emerald Isle — was spotted in the Waterford Estuary on the morning of March 25, according to a news release from the Irish Whale and Dolphin Group (IWDG), a conservation non-profit.

The body of water, located on the country’s southern coast, connects three rivers to the Celtic Sea.

An upriver odyssey

Throughout the course of the day, the whale traveled up the coastline, passing a fishing boat, a ferry and a kayaker, occasionally changing directions.

Photos show the creature venturing precariously close to the shrub-lined shore, where the water is just a few meters deep.

“These circumstances for good reason tend to bring out the pessimists in us, as experience tells us that sperm whales, at least healthy sperm whales are hardly ever recorded inshore,” IWDG said in the release.

Part of the reason for concern is that sperm whales are best equipped to navigate vertically in deep water, so in shallow water, they are effectively swimming blind.

As a result, IDWG conservationists scrambled to prepare to assist the animal in case it became stranded. However, they noted that given the size of an adult sperm whale, not much could be done with the exception of palliative care.

But, to their delight, the whale was last seen on the afternoon of March 25, appearing to exit the estuary. Since then, there have not been any reported sightings.

“This can only be interpreted as good news, as a whale of this size is unlikely to go unnoticed if it stranded on a local beach, (dead or alive),” the release said. “Let’s keep our fingers crossed.”

Rare occurrence

Since the IWDG was founded in 1990, it has recorded thousands of sightings of different whale species off Ireland. For example, 5,856 minke whales, 2,111 fin whales and 1,705 humpback whales have been documented.

In contrast, just 27 sperm whale sightings have been recorded in the past 35 years, averaging less than one per year. And most of these sightings were made further out in the ocean, making the most recent shallow water sighting quite rare.

The reason for this is that sperm whales tend to spend their lives in deeper parts of the ocean.

“Such places are typically a long way offshore, and so from the Irish south coast, you’d need to motor offshore at a good clip for some 8-10 hours before you’d find yourself in the zone…” IWDG said in the release.

While out in the open sea, the animals — which can measure up to 52 feet — are known to reach depths of nearly two miles, according to the National Oceanic and Atmospheric Administration. While traveling far below the surface, they hunt for squid, skates, sharks and other bottom-dwelling species.