This remote location meant few scientists had studied the species. Data from these studies are in the melomys recovery plan, and form the basis for much of this discussion.

The first Europeans to record the existence of the melomys were the crew of HMS Bramble, who visited the cay in April 1845. The species was apparently numerous, as sailors shot large rats with bows and arrows.

Over 130 years later, the melomys still seemed secure, as wildlife biologist Col Limpus published an estimate of several hundred individuals, following a visit in 1978.

However, a trapping survey in 1998 yielded only 42 individuals, with a population estimate of just 93 animals. The melomys was listed as endangered by the Queensland and federal governments; this decline in numbers should have been a wake-up call for both jurisdictions.

In 1999, the federal government enacted new environment laws which required recovery plans for endangered species; no plan was prepared for the melomys.

The next survey in 2002 located only 10 individuals. The melomys was now Australia's most threatened mammal, and alarm bells should have been ringing from Brisbane to Canberra; it was time for quick and decisive action. Yet two years passed before another survey verified the crash, with just 12 captures.

Given confirmation that the melomys was heading towards extinction, what urgent action was taken?

It appears none.

For example, it took four years to prepare a recovery plan. This lack of urgency begs the question: how committed were the two governments to saving this species?

A fisherman sighted one individual in 2009, though an ad-hoc sighting is not a population estimate. There was still time to act and possibly save the species.

The first "annual" count prescribed in the recovery plan was not conducted until 2014, 10 years after the previous survey. Not surprisingly, no melomyses were found, and none since.

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The melomys was most likely a relict species, isolated by rising sea levels after the most recent ice age. It had lived on its little island home for some 9000 years, and yet, within a couple of decades, it went from being secure to being gone forever.

No action was ever taken to save the species; it was simply monitored into extinction.

The loss of the melomys and its unique genetic make-up is a tragedy. It diminishes our natural world; society is the poorer for its demise.

In 2016, the international Red List of Threatened Species recorded the extinction of the Bramble Cay melomys, citing climate change - specifically, increased storm surges on rising sea levels overtopping the island, drowning the little mammals.

In life, the melomys had no champions (who were listened to), but in extinction, it has become a cause célèbre for endangered species. Today, February 18, has been proclaimed Bramble Cay Melomys Remembrance Day. This is the date, in 2019, that the then federal environment minister, Melissa Price, issued her priceless press release, "Strong protection for threatened species", in which a one-line entry recorded the extinction of the Bramble Cay melomys.

The loss of the melomys received wide media coverage, generating much criticism of the two governments' failure to protect it. As Tim Beshara of the Wilderness Society said: "The Bramble Cay melomys was a little brown rat. But it was our little brown rat and it was our responsibility to make sure it persisted. And we failed."

It would be helpful if the federal Environment Minister today, Sussan Ley, conducted a public inquiry into the loss of the melomys, to determine why the extinction happened and whether the species could have been saved.

The lessons learnt may save other endangered native animals.