A photo showing an irrigation pipeline, part of which is on conservation land with significant values, sent by a DOC scientist that led to his suspension.

OPINION: A few months ago, I was sent photos of a massive pipeline being built by a pristine, blue lake.

It was an image of environmental devastation - a digger tearing a long trench, nearly 50m wide in places, in a sensitive landscape. It was so long it disappeared into the horizon line, near the breathtakingly blue Lake Pukaki.

It was shocking, but not a surprise. The existence of the pipeline had been widely reported, and I had been contacted by several people asking me to look into what was happening with that massive scar in the fragile Mackenzie Basin. It was certainly no secret.

It was particularly newsworthy because the pipeline was partly on conservation land with high natural values. The pipeline would enable the irrigation of a massive and deeply controversial dairy farm, planning to put thousands of cows and up to a dozen pivot irrigators on the dramatic landscape by the lake.

It was an extraordinary example of environmental compromise, bringing together many issues: A sensitive piece of land, which had just been privatised through the tenure review process, would become a dairy farm that even Fonterra doesn't like. Tenure review had placed some of the land into the conservation estate, which the pipeline would run through, because it had been approved before it became conservation land. This had all been signed off by various authorities, and had become a flashpoint for the mismanagement of the Mackenzie.

I had received the photos from an environmental organisation, who - like most New Zealanders should be - was deeply concerned about what was happening, and the role of several public agencies in enabling it. (The Department of Conservation (DOC), to its credit, opposed the easement for the pipeline).

JOHN BISSET/STUFF The dry landscape of the Mackenzie Basin.

As reported by Newsroom, it turned out the photos had been taken by Nick Head, a DOC scientist who will be familiar to anyone who follows environmental issues in the Mackenzie. He is an expert on the region's flora, and knows more about the topic than just about anyone. On behalf of DOC, he has submitted on local plans and court hearings about the loss of biodiversity in the Mackenzie, highlighting the fragile state of what remains; Much of the vital environmental work being done there is thanks to his depth of knowledge.

Head has since left DOC - he was suspended, and quit two and a half months later. He is now making a personal grievance claim against DOC.

His apparent crime was sending those photos to the environmental groups, of which DOC had worked alongside regarding conservation work in the Mackenzie.

MARTIN DE RUYTER/STUFF Eugenie Sage, the conservation minister, wants DOC to return to an advocacy role.

That's it.

The leading expert on one of our greatest environmental challenges - the protection of the unique landscape of the Mackenzie Basin - is gone, because he sent photos of an environmental issue happening on conservation land that was publicly known, had been widely reported, and was visible to anyone who had flown over the basin.

As an added insult, DOC released its own photos of the pipeline, almost identical to those taken by Head.

When the Labour-led Government took power, DOC's new minister, Eugenie Sage, said she wanted the agency to return to its advocacy role. This is hardly controversial: Advocacy is listed as one of DOC's functions under the legislation enabling its existence, and something it had conspicuously stopped doing that under the last Government.

There was the time it discarded a lengthy and critical draft submission on the Ruataniwha dam for a neutral one just two paragraphs long; There was the time it filed a neutral submission on a coal mine its experts said would lead to unavoidable and substantial damage to significant conservation values.

Recently, it approved a skifield's expansion into a rare and protected wetland, despite advice from its technical advisor that doing so would destroy it.

This disregard for the department's own experts was not acceptable under the last Government, but are even less so under the current one, which has made its intentions clear.

While its Minister was publicly calling for a return to its advocacy role, the department suspended one of its scientists who, in desperation for the environment, committed what could generously be called a minor infraction. While its Minister talked about the need to save our precious wetlands, it was signing off on the destruction of one.

Nearly a decade ago, Niwa sacked its chief scientist, Dr Jim Salinger, for speaking to the media. Among his stated crimes was contributing to a TV broadcast about glaciers, his area of expertise, without telling Niwa first, and ringing weatherman Jim Hickey to tell him the Greymouth River was in flood.

Niwa was rightfully excoriated for firing Salinger, one of the country's most esteemed scientists, for the mortal sin of communicating with the public about serious issues for which he is an expert.

Since then, Niwa - at least in my experience - has been a model for communicating science with the public, and regularly makes its experts available to the media. We are all the better for it.

The hounding of Nick Head by DOC deserves the same contempt. In a time where scientists are more important than ever, DOC has chosen to punish an expert who raised awareness about an environmental issue, flagrant defying the stated intent of its Minister that the department advocate for the environment.

New Zealand has an unfortunate history of silencing scientists. After the Canterbury earthquakes, journalists struggled to get information from scientists eager to help due to authorities controlling the flow of information. Freshwater ecologist Dr Mike Joy faced disciplinary proceedings from his employer after it received a complaint from the EPA's chief executive about Joy's criticism of the EPA's chief scientist.

By providing the pipeline photos without permission, Head may have broken an internal policy, but there should be no such policy. Scientists from public organisations should be encouraged to talk about and advocate for the issues in which they are experts.

Head had raised these issues internally. In an email to his bosses, he said the pipeline route had been "completely bulldozed" and had caused "maximum destruction". He went through official channels: In that context, sending those photos was an act of desperation. That is indictment enough of the culture at DOC.

I have just completed a series about the country's biodiversity crisis, as seen through an algorithm developed by DOC to prioritise species and ecosystems for saving. It is a stark example of the problem; we are so incapable of undoing the damage we've done, we're looking to mathematics to salvage what we can.

It is also a triumph: It shows the value of scientific expertise, and how incredibly smart people can solve monumental problems for collective benefit.

By ousting one of its experts, DOC has showed no regard for its Minister, the public who rely on those experts, and even its founding legislation, which mandates DOC to "encourage and participate in educational and publicity activities for the purposes of bringing about a better understanding of nature conservation in New Zealand."

One of the greatest conservation issues for the new Government is figuring out how to protect the Mackenzie Basin. A likely method is by establishing a drylands park, a concept Sage has expressed support for and intended to pursue as policy.

It will go ahead without the person who came up with the idea in the first place - he made the mistake of advocating for the environment such a park would protect.