A dive into the whales that live in the Forth

They’ve even been spotted near Portobello


When you think about the Firth of Forth, you probably think about beach barbecues on Portobello beach, cold summer dips in the sea, and hundreds of seagulls trying to steal your chips. You probably don’t think about whales.

However, in previous centuries whales were a common sight in the Firth of Forth and the surrounding North Sea. They fed on plankton and, like Nemo, just kept swimming.

Minke whale. Captured by Ronnie Mackie

But due to some their trusting nature and how large they were, whales were persecuted by humans for their blubber, bones, teeth and baleen. Their blubber was made into oil and the meat was high in energy, while their bones, teeth and baleen were made into toys, piano keys and chess pieces.

Whales were never seen in the Forth again.

However, in 2016, the first whale sighting since the persecution was reported. Whales may have been present in the Forth for longer but since the increased use of social media it has been easier for the public to report sightings. Why have they returned? Experts are debating whether it’s due to the abundance of prey but the definitive reason is largely unknown.

Humpback in the Forth via @christie_captures_you

What’s so great about whales?

Whales really are the underappreciated gentle giants of the ocean. There are a variety of species including Sei whales, Humpback whales, Blue whales (the largest species), Minke whales, and many more. The list is as long as the blue whale itself, at 29.9m long. Not only are they beautiful creatures, but whales are inherently important when it comes to climate change.

Sei whale in the Forth. Captured by Scott Duncan

They are known to absorb around 4.4k tonnes of carbon from the atmosphere into their bodies. When they die, they don’t only provide food for passers-by (increasing biodiversity) but also, the carcass sinks to the bottom and carbon is absorbed into the massive carbon sink, called marine sediment.

Whales also increase primary production in the ocean. Primary production is essential for all ocean life to survive. Whales produce more poo than you do after a dodgy coffee, but their poo provides nutrients like iron and nitrogen for the ocean. These nutrients can increase phytoplankton blooms, which enhance productivity as they provide food for smaller animals.

As whales are extremely large, when they move through the different zones of the ocean, they move nutrients and oxygen around with them. This helps to stop creating harmful algal blooms that can decrease biodiversity, and enhance primary production.

Bob the Whale. Captured by Gordon Glen

How does this impact us?

Well, primary production is the starting point of ocean life. If you care about sea creatures, then you should care about whales. Increased primary production is known to increase fish stocks, and it is known that fish stocks are rapidly declining in the North Sea as a result of overfishing and climate change.

Whale presence in the Forth is not only great for the climate and nice for us to see, but it also has the ability to create a healthier ecosystem in the Forth. This can help kelp and seagrass beds to recover, meaning oyster beds can return. This then helps make water cleaner through filter feeding, as well as help fish and mussel stocks grow as they use the beds as nurseries for their young.

You may think not much goes on in the Forth but trust me, a lot does. Everything is interlinked. The presence of cetaceans, such as whales, can also benefit us in more ways than one. By keeping the Forth cleaner and tidying up after ourselves after beach days to Portobello and Cramond, we can all do our bit to improve ocean health and bring the whales back.

Whale in the Forth, with an injury along its back from possible entanglement. Captured by Ronnie Mackie

If you’ve seen any interesting wildlife around Edinburgh then feel free to share you images with us over on Instagram, and don’t forget to let is know if you’ve seen the Forth whale. Experts cannot be on the scene the 24/7 so shore watchers are valuable for reporting sightings!

But a quick note: if you do go wildlife spotting, please be respectful.

Bob The Humpback. Captured by Scott Duncan

I want to thank the members of the Forth Marine Mammals #forthmarinemammals for allowing me to use their images for this article.

Cover image via Seahunter Marine

Related articles recommended by this writer:

Edinburgh Hive vs Glasgow Hive: A scientific study into which is better?

How the pandemic changed our concept of time

• Here’s a roundup of the best dressed in Edinburgh’s Main Library right now