First North Sea rotation with harbour porpoises and wind farms!

North Sea


What a first rotation!

I had to wait two years to start, but on March 20th I boarded the DFDS King Seaways in IJmuiden, the Netherlands. I was eager to get going, but also quite nervous. What would happen in the next 19 days? Would I see many cetaceans? I was really blessed with the weather during my first week, hardly any wind led to calm seas, which then led to many harbour porpoise sightings!

On my second day leaving the harbour of North Shields the observation deck had been opened and I was able to start my deck watches from the front of the ship. Notable deck watches included the 23rd and 24th of March, on both days 14 harbour porpoises were sighted, the next day we saw 21 harbour porpoises and two white-beaked dolphins but the best was still to come. On the 26th of March an amazing 26 harbour porpoises were observed. It was so great to be joined during the deck watches by so many enthusiastic passengers, helping me look out for porpoises even in the early hours of the mornings. They asked many different questions and were really keen to learn more. A frequently asked question was about wind farms and their effects on marine life in the North Sea.

When you leave the harbour of IJmuiden the wind farm on the right is the first you come across, this is the wind farm; Egmond aan Zee and is actually the very first wind farm in the Netherlands. About half an hour later the King passes a second wind farm located on the left which is named after the Dutch Princess Amalia.

While transiting past these wind farms, passengers ask me whether these farms have a bad effect on marine life and marine mammals in particular. Wind farms are very interesting and their effect on marine wildlife is strangely enough, both negative and positive.

During the construction phase of a wind farm, the effects are definitely negative. Research has shown that harbour porpoises avoid the area by at least 20km, and they do this because of noise pollution. Harbour porpoises like any other marine mammal use sound to feed, communicate and navigate to name a few. And the noise of the construction masks these sounds which porpoises rely on. The loud noises could lead to temporary displacement of these animals from their critical habitats.

However, after construction is finished, something amazing happens. Life finds its way to the wind farm. The foundation of the wind turbines can act as an artificial reef which, in the first couple of years, attracts species like barnacles, muscles and anemones. These species in turn attract crustaceans and fish, and they, in turn, attract seabirds and marine mammals like the harbour porpoise. And on the Dutch side, I have definitely seen quite a few harbour porpoises in the vicinity of the wind farm. Another positive thing about these wind farms is that shipping and fishing activities aren’t allowed near them, which means the new habitat that has established itself in the wind farms can thrive without too much disturbance.

Of course, the wind turbine still produces some noise but the disturbance is far less than during construction and less noise than a passing ship. Which could mean that marine mammals also use the wind farm as a little safe haven from all the noise that humans produce in our seas and oceans.

I am really looking forward to seeing what this season will bring! I would love to see bottlenose dolphins, white-beaked dolphins and minke whales. It has been many years since I last saw bottlenose dolphins, so they are high on my list. But I am also really curious if we will see any more uncommon species that might venture into the North Sea like Atlantic white-sided dolphins or common dolphins, and who knows maybe something even rarer. Wouldn’t that be amazing!

I am really looking forward to my next rotations and what they will bring regarding both sightings and interactions with passengers. Hopefully, I can help lots of passengers spot cetaceans and enlighten them about these amazing creatures in the North Sea.

Ocean Conservationist Mathilde (North Sea)