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Thames Estuary has the smallest whale

Some animals have been living on the Thames since 2016. The society has took acoustic and visual surveys to see if ‘significant numbers’ of animals were living in the river.



Despite their reputation for being quiet and elusive, harbour porpoises are flourishing in the Thames Estuary, according to a recent survey.

According to a survey by the Zoological Society of London, Europe’s tiniest whale uses the bustling river as a “vital habitat.”

The outer Thames, where the river joins the sea, has been home to “substantial numbers” of the animals for a period of years, according to acoustic and visual surveys.

The results, according to scientists, show that marine mammals need to be better protected from ship traffic, fishing, and offshore wind farms.

To communicate with one another, the little whales use very high frequency echolocation noises.

The clicks have a frequency of about 120 kHz, which is approximately six times greater than human hearing.

In order to accurately pinpoint the location of the porpoises, researchers deployed a specialized hydrophone array to capture their sounds.

Two surveys conducted over a seven-year period revealed a significant amount of porpoises in the estuary.

The crew made 16 sightings and 31 individual detections of porpoise groups in the spring of 2022. Seven of the sightings had both hearing and sightings.

‘Estuaries are vital for many marine species, especially for rearing young,’ said Anna Cucknell, project manager for ZSL ecosystem restoration.

Like the proverbial “canary in the coalmine,” the harbour porpoise is a “sentinel species,” whose presence indicates how well-balanced an ecosystem is.

The Thames and maybe other UK estuaries are crucial habitats for harbor porpoises, as evidenced by the porpoise numbers we have counted, which are comparable to those counted in European protected locations.

Cucknell said that, given that the porpoise population has been found to be declining in other areas, the rapid development in the Thames is worrying.

According to her, the fact that there were so many harbour porpoises in the Thames Estuary this year suggests that many of them were traveling to unprotected, offshore areas in search of food and breeding grounds.

According to the Wildlife and Countryside Act, harbor porpoises are a protected species in the UK, however the Thames canal is a bustling gateway because to regular ship traffic, significant fisheries, and offshore windfarms.

We hope that our analysis will help guide future efforts to safeguard this elusive marine mammal and serve as justification for broader coastal and estuary protection zones in the UK.

The harbour porpoise, a kind of marine animal that comprises whales, dolphins, and porpoises, is the smallest cetacean in Europe and measures just under two meters in length.

Since they have small bodies and live in temperate waters, they must eat virtually constantly to keep their high metabolisms in check.

Harbour porpoises are readily startled by noise in the water from human activities like boat engines or building noise because of their sensitivity hearing.

They might also get caught in fishing nets that vessels use to catch other kinds of fish.

The southern North Sea coast of England at the mouth of the Thames was one of five Special Areas of Conservation notified in 2019 as being significant for the species.

“We are delighted to discover that porpoises are still using the Thames estuary in significant numbers, highlighting the importance of estuaries for this charismatic British marine mammal,” continued MCRI scientist Dr. Oliver Boisseau. “This emphasizes the need to undertake baseline research on protected species in other little studied UK coastal waters.”