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The curious case of the porpoises and the Dutch wind farm

15 Mar 2018 James Dacey
Harbour porpoise (Courtesy: Ecomare/Salko de Wolf)

“Life uh… finds a way” is one of Jeff Goldblum’s many great lines in playing chaos theory mathematician Ian Malcolm in Jurassic Park. In his wry style, Malcolm is pointing out nature’s cunning habit of thriving, even when humans interfere with natural habitats. Or put another way, you can place a giant fence around a T. Rex but it’ll still find of way of eating you in the end.

What’s that you say – Jurassic Park’s not a nature documentary? You’ve just ruined my childhood. Anyway, this week I’ve been in the Netherlands investigating a more modest “life finds a way” scenario, involving the humble harbour porpoise (Phocoena phocoena). I’ve been working with US filmmaker Saskia Madlener to shoot a film about how marine wildlife responded to the creation of Windpark Egmond aan Zee (OWEZ), the first offshore wind farm built off the Dutch North Sea coast. Perhaps surprisingly, a study published in 2011 found that the porpoise population in this zone – 10–18 km from the coastal town of Egmond aan Zee – is larger now than it was just before the windfarm existed.

Reef effect

Obviously, it’s great news for the porpoises. But the presence of mammals so high up the food chain is also an indicator of a thriving ecosystem. The study led to the intriguing suggestion that the underwater infrastructure of offshore windfarms can create sheltered reef environments, with better foraging opportunities than an otherwise homogenous sea floor. Hard substrates can host small organisms, which become prey for fish, which in turn become prey for porpoises. So on the face of it, offshore windfarms might be a win–win situation – a renewable-energy source whose very existence can allow marine wildlife to flourish.

Windpark Egmond aan Zee

Now come the many caveats, of which I’ll just name a couple. First up, a separate study published in 2013 of the Nysted windfarm in the Danish western Baltic sea found the opposite result. The harbour porpoise population dramatically reduced during the construction of that windfarm and had barely recovered 10 years after the construction was complete. Secondly, it needs to be noted that fishing is now prohibited at the Egmond aan Zee windfarm, which has led to a significant reduction in shipping traffic in the area. So is the thriving marine life just a product of the area becoming a protected zone? Presumably, many of those fishing boats are still active – so has it simply shifted the environmental impact elsewhere?

These are some of questions we will explore in the film, which will be published on this site in the next few weeks. We visited the small port city of IJmuiden where we interviewed Meike Scheidat, a marine researcher from Wageningen University who led the 2011 study. We wanted to discover the strengths and limitations of the study, which involved tracking the echolocation click-activity of porpoises by suspending hydrophones from buoys. Scheidat’s office contained a menagerie of marine wildlife posters, books and decorations – exactly what you might expect from a researcher immersed in her field.

Meike Scheidat (left) in her office in IJmuiden

But not everyone was happy with the arrival of the OWEZ wind farm. Some in the local fishing community were unhappy with the shipping ban, especially with the speed at which it came into effect and the lack of consultation. So we next headed to the Hague where we interviewed the fisherman Rems Cramer on a boat in Scheveningen harbour. Cramer identifies strongly as “a hunter” of fish, but realizes that the fishing industry must adapt its methods to survive. He is investigating more sustainable fishing practices with a group called Vissen voor de wind (“fishing for the wind”) with support of the Dutch Ministry of Economic Affairs and the European Fishery Fund. Cramer believes fishing could resume at OWEZ if trawling is replaced with lighter touch methods, such breeding of mussels on floating solar panels.

The winds of change

Also on our tour was downtown Amsterdam, where we visited the HQ of Dutch utility company NUON, which constructed the windfarm in partnership with Shell. One of the lead engineers Henk Kouwenhoven spoke about the lessons learned from OWEZ as well as the current state of the wind energy sector in the Netherlands. At present just 6% of the Netherlands’ energy comes from renewable sources but the nation is committed to hitting its EU target of 14% by 2020, rising to 16% by 2023. Meanwhile, the Dutch government has set a target to lower the cost of offshore wind power by 40% in 2024 compared to 2014. Coupled with the decision to reduce the nation’s historic reliance on natural gas, it all suggests that the Dutch government is very keen for the rapid expansion of offshore wind.

That is why it will be so important to consider the potential environmental impacts of construction, operation and decommissioning of these sites. Kouwenhoven believes that a vital part of that process will be to learn lessons from the OWEZ example and to minimise environmental impacts through technologies such as developing drilling equipment with reduced acoustic noise.

This film will be part of our new series of films exploring environmental challenges and their potential solutions. The issues in these films are often messy, complicated and involve competing interest groups. That is precisely why the issues are so interesting! Also, rather than focussing purely on grave environmental threats, these films will identify ways in which science and engineering can help us to adapt to meet these challenges. The first film in the series looked at Mexico City’s struggle to provide its citizens with drinking water. Another film to appear on this site soon will look at efforts in the US city of New Orleans to adapt to live with increasing flood risk in the face of climate changes.

I can’t promise these films will gross as much at the box office as Jurassic Park. But what I can guarantee is that you’ll have plenty of meaty environmental challenges to sink your teeth into. All available right here, free of charge, on the new look Physics World website.

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