The photo project was done for the organization Fishlove and included some other U.K.-based celebrities posing in the buff with critters ranging from bass fish to sharks. Its goal is to raise awareness of how overfishing is destroying the oceans. The release of Gillian's nearly nude pic, which was snapped by French portrait photographer Denis Rouvre, is timed with a European Parliament vote on banning destructive forms of deep-sea fishing in the Northeast Atlantic. The Fishlove organization is trying to rally voters to sign a petition ending deep-sea trawling – which, according to scientists, is negatively impacting the fish population and their habits – and Gillian solicited signatures in a Twitter post. Photo: “Fish Love” Project by Photographer Denis Rouvre. Gillian Anderson. (Photo by Denis Rouvre)

Belarusian police officers detain an opposition supporter during a rally to protest against the disputed August 9 presidential elections results in Minsk on September 6, 2020. Tens of thousands of Belarusians staged a peaceful new march on September 6, keeping the pressure on strongman Alexander Lukashenko who has refused to quit after his disputed re-election and turned to Russia for help to stay in power. (Photo by TUT.BY/AFP Photo)

Shiite Muslim pilgrims march with flags en route to Karbala from Nasiriyah in Iraq's southern Dhi Qar province on September 5, 2022, ahead of the holiday of Arbaeen. (Photo by Asaad Niazi/AFP Photo)

The abandoned 77-metre (250-feet) cargo ship MV Alta is pictured stuck on rocks near the village of Ballycotton south-east of Cork in Southern Ireland on February 18, 2020. A “ghost ship” drifting without a crew for more than a year washed ashore on Ireland's south coast in high seas caused by Storm Dennis, the Republic's coast guard said. (Photo by Cathal Noonan/AFP Photo)

A bride gets tested for the coronavirus disease (COVID-19) at a nucleic acid testing site, following the coronavirus disease (COVID-19) outbreak in Shanghai, China on November 15, 2022. (Photo by Aly Song/Reuters)

Anti-frost candles burn in apricot plantations to protect flowering buds and blossoms from frost in the midst of the Swiss Alps, in Saxon, Canton of Valais, Switzerland, 05 April 2019. With an unusually low temperature forecast for the season, fruit growers try to protect their buds from frost damage with two different means, icy water or large candles. (Photo by Valentin Flauraud/EPA/EFE)

Pigeons walk in front of the Russian Foreign Ministry building (C) in Moscow on April 8, 2024. Russian Foreign Minister Sergei Lavrov will visit Moscow's key diplomatic and economic partner China on April 8-9, his Ministry said in a statement. (Photo by Alexander Nemenov/AFP Photo)

Palestinians hit injured Israeli settlers, center, detained by Palestinian villagers in a building under construction near the West Bank village of Qusra, southeast of the city of Nablus, Tuesday, January 7, 2014. Palestinians held more than a dozen Israeli settlers for about two hours Tuesday in retaliation for the latest in a string of settler attacks on villages in the area, witnesses said. The military said the chain of events apparently began after Israeli authorities removed an illegally built structure in Esh Kodesh, a rogue Israeli settlement in the area. In recent years, militant settlers have often responded to any attempts by the Israeli military to remove parts of dozens of rogue settlements, or outposts, by attacking Palestinians and their property. The tactic, begun in 2008, is known as “price tag”. (Photo by Nasser Ishtayeh/AP Photo)