Deep Dive

the surprising, intriguing, and downright
wacky things found in the River Thames

The River Thames is one of London’s most popular attractions, not only bringing in millions of overseas visitors each year but piquing local interest, too.

As well as being a tourist hotspot, it is England’s longest river and the second-longest river in the United Kingdom.

For that reason, there’s a lot more to the Thames than meets the eye! We took a deep dive to reveal the sea life that has been spotted in the river, as well as the wackiest items that have been discovered under its surface. We also explored the items of waste most frequently found in the water, many of which should have been recycled instead. Read on to discover more.

What sea life can be spotted in the Thames?

Visiting the Thames is a perfect place to spot marine life, with the river being home to everything from whales, dolphins, seals, crabs, and eels.

Let’s start with the most common sea creature found in the Thames beside fish… whales! These wonderful marine mammals have been sighted in the river as early as 2006 and date all the way up to the current year. One of the many whales spotted was nicknamed Benny by local residents and roamed the river for an extraordinary three months before finding his way home.

Various other types of whales have also been found in the Thames, including the humpback, bottlenose, beluga and minke species. Of course, these creatures are a long way from their usual home in the Arctic and Antarctic Oceans as well as the North and Mediterranean seas, so this begs the question, why do whales swim in the Thames? Well, no one knows for sure, but a possible explanation is that they like to migrate south for the warmer waters.

In addition to whales, dolphins and even a range of shark species have been found to inhabit the capital’s waterway. The first sighting we have on record is 2018, when a dolphin was sighted near Barnes Bridge in West London. A year later, a harbour porpoise was also seen swimming nearby.

Some other popular residents of the Thames are seals, which have been seen in the river since 2013, alongside mitten crabs, eels and short-snouted seahorses.

And, saving the most thrilling sighting until last, the Loch Ness monster! The mythical creature was spotted in the Thames in 2016 with onlookers capturing a brief look of the dark shadow. Bystanders reported that it was too big to be a shark and looked very different to any creature they’d seen before. How mysterious!

Moving away from sea creatures, birds are a popular sighting at the Thames with many making the river their home. These include the most common species, Redshank and Avocet birds.

According to our research which examined articles and research reports of animal and unusual item sightings over the last 10 years, last year (2021) was the most popular year for animal sightings.

Humpback Whale
Harbour Porpoise
Starry Smooth-hound
Short-snouted Seahorse
Tope Shark
Beluga Whale
Loch Ness monster
Mitten Crab

A rundown of the strangest items ever found in the Thames

Now let’s get into the wacky stuff! As well as showcasing the sea life residing in the Thames, we have also explored some of the most curious items that have been found in the river over the years.

We’re starting strong in 1995 with a giant Michael Jackson statue that was found floating down the river, to promote his album ‘HIStory’. The deceased singer chose to float a giant 10-metre statue of himself down the Thames and this was one of nine counterparts found across Europe.

26 years later, in 2021, a 16th century sword was fished out of the Thames. The sword, which had a wooden handle, was thought to have survived at least 400 years in pristine condition, as it was buried in the oxygen-free mud.

Another fascinating item spotted lurking in the shadows is a 5,000-year-old human bone from the Stone Age. It is reported to be dated between 3516 and 3365 BC and belonged to a person who was around 5ft 7.

This is in addition to a 28-metre-long megalodon shark tooth. It’s said that this huge beast swam the water 1.5 million years ago.

Lastly, there have also been reports of a Roman brothel token being fished from the waters around Putney Bridge, as well as a skull segment from a 30,000-year-old woolly rhino, and a plastic crocodile which initially terrified onlookers who thought the toy was real!

Giant Michael Jackson statue
16th-century sword
Skull segment from a 30,000-year-old woolly rhino
Iron ball and chain
Roman brother token/coin

What are the most commonly found waste items in the Thames?

Finally, our study explored the waste items found in the Thames that shouldn’t have ended up there – many of which could have been recycled instead.

A report by Thames21 found that wet wipes are the most littered item in the river. When mixed with mud, the wipes form slimy layers. One of these mounds – or fatbergs - was reported to have grown in height by 1.4m between September 2014 and May 2019. This covered approximately 1000m2 - the equivalent of four tennis courts.

We also delved into the worst wet wipe and plastic bag hotspots. Hammersmith Bridge Southside comes out on top for wet wipe hotspots, with Fulham Football club following in second place and Battersea Bridge coming in third.

Newcastle Drawdock comes in first place as the plastic bag hotspot, with O2 flats in Greenwich coming in second place and Galleons Point following in third.

And which areas contain the most waste? The top floating waste hotspots of the Thames are Small Profits, Queen Caroline Drawdock and Crabtree Wharf.

Pick a waste hotspot category below:
Hammersmith Bridge Southside
Fulham Football Club
Battersea Bridge
Vauxhall Bridge
Newcastle Drawdock
O2 Flats
Galleons Point
Small Profits
Queen Caroline Drawdock
Crabtree Wharf
Old Swan Wharf
Millwall Drawdock
Cutty Sark
Point Wharf
Thamesmead (Redbourne Drive)
Concrete Barges
Erith Marshes
Purfleet RSPB Rainham
Grays Beach

The top lightweight items fished from the river

Of all the items found floating in the Thames, food wrappers were found to be the most common, making up 20% of all lightweight items floating on the foreshore of the Thames between 2015-2018.

Cotton bud sticks were the second most common making up 16%, with disposable cups coming in third and making up 9%.

Drink bottles came in sixth on the list - perhaps unsurprising given that a total of 97,019 bottles were recorded and removed between 2016-2019. Shockingly, water bottles account for almost half of bottles ever found in the river – the majority of which could have been locally recycled.

Top lightweight items found on the foreshore of the Thames 2015-18
% of total litter found
Food wrapper - 20%
Food wrapper
Cotton Bud Stick - 16%
Cotton Bud Stick
Cups - 9%
Bottle lids - 8%
Bottle lids
Take-away containers - 8%
Take-away containers
Drink bottles - 3%
Drink bottles
Building insulation (polystyrene/foam) - 2%
Building insulation
Straw - 2%
Cigarette butt - 2%
Cigarette butt
Lollipop stick - 1%
Lollipop stick

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To gather the data, we looked at articles detailing sightings of various animals as well as unusual items in the Thames over the last 10 years.
We also looked at the Zoological Society’s Zoological Society’s report on the ‘State of the Thames’
The litter statistics have been taken from the Thames21’s report on ‘Plastic Pollution in the Thames’