How I rediscovered a rare cockroach

The rediscovery of the roach is poignant in its timing.

Art by Maxim Adams

If we generously expand the definition of “fame” – and of “15 minutes” – I had mine recently, having helped rediscover a purportedly extinct population of cockroaches on Lord Howe Island. The wingless soil-burrowing cockroach Panesthia lata is unique to Lord Howe Island, and was last seen more than 80 years ago. I was pretty chuffed by the interest in the story, not only from scientists, but also the general public, including locals of the island itself. 

“I think I killed one the other day,” one told me at the pub, holding up a picture of the flattened corpse of what mercifully turned out to be an invasive American cockroach.

“Is that the same as the stick insect?” asked another.

While not headline news to all, this is a sensational development for the Island’s ecosystem, which has taken two centuries of beatings at the hands of industry, people, and introduced species. Lord Howe Island was completely unknown to humans until 1788, when it was discovered by British colonial sailors en route to Norfolk Island. Encountering an unprecedented and naive island fauna, they immediately set about slaughtering everything in sight. Rejoicing at the “very stupid birds”, one diarist recounts his strategy of breaking the legs of a native woodhen and using its “doleful cries” to attract an additional 60 birds to dispense with.

However, for all their efforts, sailors could never match the destructive powers of rodents. Rats reached the island in 1918, swimming ashore after the supply ship SS Makambo ran afoul of rocks off Ned’s Beach in the island’s northeast. Within 10 years, five species of birds had gone extinct. Within twenty, all reports of Panesthia lata had ceased. Presently, at least 10 invertebrates are recognised as completely extinct from rat predation, with many more likely having disappeared without ever being known to science.

The rediscovery of the roach is poignant in its timing. In 2019, all rats were exterminated on Lord Howe, in the largest rodent eradication ever undertaken on an inhabited island. Seemingly overnight, the ecosystem began to recover. Seabirds absent for over 80 years were seen nesting in the northern forests, those same “stupid birds” hunted by early sailors reached their highest numbers in decades, and, of course, a tiny relict population of soil-burrowing cockroaches once more began to grow. 

It begs the question: why wasn’t this done sooner? A scientific consortium had outlined the need for rat eradication in the 1970s, and the requisite technological and organisational infrastructure have existed at least since the 1990s. The reasons were, as they too often are, political. Return on investment was a major concern and led to a commissioned cost-benefit analysis. It found that protecting the ecosystem would pay for itself countless times over, as such analyses tend to do. 

Other objections from stakeholders included the assertion that rats had reached “equilibrium” within the system and need not be disturbed, that it could affect agricultural output, or that the side effects of the rat poison were unknown. Each argument was systematically rebutted, and in 2015 the eradication was finally launched following a plebiscite of the islands’ citizens, where it scraped in with 52 per cent of votes. 

This highlights a deeply bad faith streak that pervades modern conservation. Many of the ‘concerns’ raised were obviously spurious, intended only to delay ecological efforts, but were cynically branded with scientific terminology. It’s a pattern seen even at the largest scales. Recall the Turnbull government’s $444 million investment into reef “research” and “alternatives”, emphasising strategies to cope with, rather than counteract, climate change. The jury is well and truly out on that front: unless the seas cool down, no amount of alternatives will save the Great Barrier Reef. I’m sure it’s a coincidence that the board managing that fund is supported by BHP and Rio Tinto.

Very recently, the Federal government announced a bold new commitment to “zero extinction” going forward. This initiative dramatically expands the number of species and communities listed as threatened and endangered and is touted by interested parties as a sorely-needed return to science. Yet, as critics point out, it curiously neglects to acknowledge the processes actually threatening them in the first place. It extends a precedent established in 2019, when the Environment Department circulated internal memoranda explicitly blocking scientists from assessing and listing new ecologically threatening processes. Again, the fact that these threats arise from industry, agriculture and development is surely no coincidence.

At best, these strategies show governments baulking in the face of the modern environmental catastrophe and scrambling for an easy fix. At worst, “research” is deployed by managers as a smokescreen to advance financial self-interest under the guise of scientific rigour.

The case of Lord Howe Island exposes the frailty and cynicism of managers’ calls for due diligence and alternatives. Upliftingly, it also shows that we can still push through to face ecological problems head-on. I can only hope that the cockroach inspires more conservation research to translate into conservation action.