OTTAWA – File this under: Useful federal trivia.

The number one issue raised by the general public in correspondence with Prime Minister Justin Trudeau? Seal hunting.

More than 2 million messages about seal hunting have been sent to the PMO since Trudeau took office on Nov. 4, 2015, according to documents tabled in the House of Commons.

Though it in no way has been a major issue dogging this government, a quick search shows several groups and high-profile celebrities have been pushing Trudeau to end the commercial hunting of seals.

Inuit hunters and non-Indigenous hunters in Newfoundland and Labrador have defended the practice, and Trudeau and his caucus voted in favour of, and passed, Bill S-208 to mark May 20 as "National Seal Products Day" last year.

The documents do not specify how much of the correspondence on this subject was either for, or against seal hunting.

The response to a June Order Paper Question from Conservative MP Kevin Waugh listed the top 10 topics in terms of volume, not all of which came in a mail bag -- it includes electronic form emails that campaigns can encourage people to stick their names on and send in.

Overall, environmental and energy issues appeared repeatedly on the list, including climate change, which was the second-most communicated issue, and pipelines, which was the fifth hottest topic.

Other matters that amassed the most mail? Terrorism and legal settlements, which could potentially be connected to Trudeau's controversial $10.5 million settlement to Omar Khadr in the summer of 2017.

The top 10 issues amassed a total of more than three million pieces of correspondence.

Here's the full rundown of what Canadians are writing to the Prime Minister about:

Seal hunt: 2,013,389 pieces of correspondence Climate change: 240,376 pieces of correspondence Test on animals: 227,229 pieces of correspondence Site C dam: 148,005 pieces of correspondence Pipelines: 140,859 pieces of correspondence Falun Gong: 138,273 pieces of correspondence Natural gas: 127,294 pieces of correspondence Legal settlements: 126,606 pieces of correspondence Terrorism: 86,451 pieces of correspondence Renewable energy: 65,984 pieces of correspondence

Total for the top 10 was 3,314,466 pieces of correspondence.

If there’s a burning issue you want to raise with Trudeau, his office hosts an online submission form, or if the classic postal mail is more your style, you can address him at: Office of the Prime Minister, 80 Wellington Street, Ottawa, ON K1A 0A2.