The evolutionary triumph of ‘Rattus Rattus’

We are messing with nature yet again, but now under the guise of ecosystem repair, sustainability, invasion dynamics and naturalization. And, is it working?

🏝🐀 Ever heard of Rat Islands? Or Rabbit Island? Or the islands of Orona, Socorro, Grass and Wake? These little known islands and many more like them, reveal shocking and fascinating stories of ecosystem collapse and revival. Bio-invasions by design or accident, starring not just human beings, but also rats, cats, dogs, pigs, rabbits, goats and other domesticated vertebrates. Referred to as “detonator events”- most often caused by human projects, occurred not just on Rat Islands but many islands dotted across the earth. These super remote locations, are now subject to “invasive vertebrate eradication programs”. Touted by scientists and policy makers across the board as “a key island restoration tool”, these folks are rushing to establish improved ecosystems on hundreds of islands in the Pacific, Atlantic and Indian oceans. To a lay person, the Bio-engineering of islands equates to the return of biodiversity. Restoration by all means.

About 700 such programs are in action as of now, monitored by wildlife institutions, scientists, environmental organizations, activists and conservators. Scientists from around the world, are inventing “ways” to employ genetic engineering (they say for conservation purposes). These “ways” even as they appear problematic and full of speculative expectations, are by intent trying to undo the insuperable damage caused by human invasion of pristine non-human ecosystems. We are messing with nature yet again, now under the guise of ecosystem repair, sustainability, invasion dynamics and naturalization. And, is it working?

🐀 Rat Islands (Kiska, Amchitka and Semisopo) were once a haven for migratory birds, containing plenitude of Fish, Crabs, Molluscs, Otters, Seals, even Foxes and Reindeer. Human beings did not bother colonizing the islands or perhaps at best never found it till 1824. Catastrophe struck these islands, thanks to a Russian expedition lead by Fyodor Petrovich Litke. The ships and crew brought Rats not by design but by “accident”. The freeloading rodents ran amok into a rich ecosystem, devouring what they could and consequently multiplied very rapidly. Much like man’s colonization of the earth, Rats followed suite, rapaciously consuming all they could, while destroying the island’s delicate ecosystem. Within two decades the biodiversity of these tiny islands had collapsed. Had the colonizers committed a genocide by “accident”? Or had the rats destroyed the existing food-chain by “design”? Clearly inhospitable for human settlement, the islands were abandoned by the Russians, later invaded by the Japanese during WW2, recaptured by the Americans and consequently named “Rat Island”. Regardless, Rats traveling on various ships infiltrated the entire Aleutian archipelago and beyond into mainland Alaska.

A coordinated conservation effort (2002-08) “removed” rats from Rat islands. Today Rat Islands are ‘Rat-Free’ again, thanks to scientific vigor and the regenerative capacity of the ecosystem. Renamed ‘Hawadax’ (Aleutian language), the island’s rat culling project is a success story of “invasive vertebrate eradication”. The coordinated intervention (lasting almost 6 years) did manage to bring back a few migratory birds and also provide regenerative habitats for Fish, Crabs, Molluscs etc. Yet one cannot discount that many of the island's local bird populations were negatively impacted. A number of the existing animals were also poisoned, explicated as “higher-than-expected nontarget mortality”. A U.S. Fish and Wildlife Service investigation reveals the consequences of dropping ‘Rodenticides’ from the air. “Survey crews found over 600 dead birds, of them 55 eagles… Even as a majority of rats were successfully taken out, the islands have not returned to their erstwhile biodiversity…” (USFWS 2022).

Regardless, the University Of San Diego claims “a fully recovered system”. A brief description of the grand quest: “At the final target, they dropped their ordnance – poison from the air. They also set thousands of traps by hand on the ground, trying to be as unobtrusive as possible to avoid detection” Christian Science Monitor 2009. Clearly conservation philosophy, planetary management and practice are not in sync. Restoration is not some project or policy, and it may take thousands of years, if not more to complete it’s course. However some scientists are having a lot of fun, playing with invasion dynamics at these invasion hotspots!

🐀 One of the largest rat killing projects yet undertaken, was on Henderson Island (close to Pitcairn) in the South Pacific. Henderson Island is a World Heritage site as well as a Bio-invasion site. In August 2011, to rid the island of Rats, 34 tonnes of bait laced with the anti-coagulant poison ‘brodifacoum’, were dropped from helicopters round the clock. The project (costing about £3.5 million) was organized by the Royal Society for the Protection of Birds (RSPB). Following a rapid drop in the Rat population on Henderson, by May 2012 scientists monitoring the results concluded “…within a span of 10 months, Rat numbers have recovered…”. By no means could the targeted “poison drops” wipe out all the rats. Worse, the toxic substances present in the drops, had negatively impacted several non-targets (birds, crabs and aquatic creatures). However leading Cambridge scientist Michael Brooke insists that “if rats could be totally removed, we might be talking hundred times the abundances we see today among seabirds returning to Henderson Island…that would be a huge conservation gain.” Pushing his logic in numbers, he states “It’s simple math… A female rat bears a half dozen pups every few months, and female pups mature in two to three months…” If we apply such scientific logic (and maths) to our own population explosion, this sort of “invasive rodent removal” appears hypocritical and deficient. Anyhow the Rats of Henderson Island persisted, and in some cases developed better immune systems to boost resistance. Urban Rats and ‘Mickey and Mini Mouse’ could learn a thing or two from these hardy island Rats, about resistance and regeneration!

Hundreds of eradication events have also been orchestrated to take out cats, pigs, rabbits and dogs. The global success (or failure) of such projects can be examined when we check the figures. A recent study reveals the success rates - New Zealand (24.1%), Australia (12.6%), United Kingdom (12.3%), United States (11.1%), France (8.6%), Japan (7%) Mexico (5.0%), Indonesia (4.2%) The Seychelles (3.9%), Fiji (3.8%), Ecuador (3.7%). See full list of eradication events. Remote oceanic islands harbor a wide range of species found nowhere else in the world; yet, many of these species have already being driven to extinction by the introduction of alien species, most notably rats, cats, pigs and dogs. The ruling opinion, framed by scientists, governments and wildlife conservation institutions is in favor of eradication programs, regardless of the actual success rate or the yet unknown long term outcomes (and risks). If it’s about Rats, Kill Em All!

This schism reveals our preoccupation with the “pristine” and “restoration”. While some call it “Planetary Management” others prefer to use the regular terms like “invasive species” and “biodiversity protection”. Yet we know well of that, as a tradition in western culture, and a Cartesian philosophy, of dualism, separating humanity and Nature. This anthropocentric pursuit, can be felt amongst many leading scientists and conservationists. Hence, Ecosystem management or call it ‘Bio-tampering’ can also be considered as a form of biological warfare, especially for those at the receiving end. “Our global impact is finally receiving the scientific attention it deserves. The outcome will largely determine the future course of evolution… it is possible to create common set of traits including simplified food webs, landscape homogenization, and high nutrient and energy inputs.” surmises David Western. The above outcome, imagined by folks like David Western, is at best speculative and dependent on constant human interference. The institutional mindset, much like how a State thinks and operates, is very good at devising ‘brutal solutions’ to combat problems, and so is the case with ecological damage reparation and controlling overpopulation and species loss - leading to ever new adverse effects along it’s path to restoration. Makes us wonder, who then at a planetary level is the true invasive species? Who introduced Rats (by accident or by design) into all the islands across the world? Categorized human impact (either intended or unintended) is clearly a murky area, and most scientists and institutions across nations are tacitly mute about it. Dropping poisonous bombs from the air is easier perhaps.

Drawing a definitive line between the human and natural realms serves no purpose anymore. Our imprint (domination) is as ancient, as colonialist, as invasive, as scientific and as pervasive. The distinction between humans and the rest of the species thus lies not in our evolutionary strategy, but in the “side effects of our global dominance” over thousands of years. The argument does not resonate with most wildlife conservationists, that human orchestrated violence plays a key role in all such acts of restorations. ‘Pogroms’ to wipe out one given species, in order to salvage the rest. Similar to naturalization of citizens, wildlife conservation backed by scientific prowess, is brutally applying identical ‘solutions’ upon creatures and critters, as precious or rare, as despicable or problematic. They call it “biosecurity” and part of “environmental policy” yet in reality mini genocides are going on across the world. The real effects of such ‘invasion dynamics’ and naturalization are yet to be felt. Be it “Rat Spills” across the Pacific Islands or “Cat Spills” in Australia, Borneo and New Zealand or Oil Spills allover the world, we humans are the primary cause of all such environmental disasters. Regardless of which spillover event, the rest of the living species ends up paying a devastating toll, or worse have already gone extinct. So was it the Dutch people or the Dutch Rats, Cats and Dogs who were responsible for the extinction of the beautiful Dodo?

“What can we say about future evolution in a human-dominated world? We were invited to speculate freely…” (PNAS Human-modified ecosystems and future evolution) Speculate as much as you wish and can, yet nature reveals what we actually need to know. “We assumed if rats got into an ecosystem, it was trashed forever.” says Vernon Byrd, a biologist working at US Fish and Wildlife Service. As short sighted or anthropocentric that view sounds, actually it is us humans (by our sheer presence) who have “trashed” ecosystems and perhaps “forever”. Yes indeed, hundreds of convinced experts repeat “Rats don’t belong there”. However they tacitly avoid a simple question- where do they belong? Sewer Rats or plantation Rats or island Rats, we view the ‘Rodentia’ species as vile, vicious and vermin. Never mind all the Rats in captivity, that we experiment on every day, testing new medicines, pesticides, perfumes, fast-food, cardiovascular patterns and even psychological responses. Rats are also employed (or say forced) by scientists, shoved into radioactive zones like Chernobyl “to study long term radiation affects”. Meanwhile in Cambodia, Vietnam and Kenya scientists and NGOs are employing Rats to detect landmines and bombs, still lying around from previous wars. So clever aren’t we?! The estimated global population of Rats is 7 billion. That's almost 1 rat for every human! Lets spare a moment to celebrate the evolutionary triumph of the ‘Rattus Rattus’ 🐀🥇🐁

7 billion is a preposterous figure regardless if it’s about human beings or Rats. Hence no amount of eradication events, aerial bombardment and bio-tampering is able to wipe out all the “unwanted Rats” now living in almost every corner of the world, with or without us. The “unintended consequences” are bound to catch on, post all such eradication programs. Just like the “accidents” of the past, which occurred on many islands, including Rat Islands. The bio-invasion is far from over, past it’s initial success, there is much to be said about the ethical and welfare implications, and the people who approve and fund all such ecosystem restoration projects. There is a high possibility that Rats across the world are equally evolving, in terms of their preference for natural food over poison pellets and sausages laced with ‘brodifacoum’. (pathetic violent scientists)

Over millennia, human domestication of ecosystems has visibly devastated species diversity across the planet. Less we continue to just blame Rats, our global fetish for cats and dogs is also questionable. They too, if not by design but by accident have wiped out thousands of species, willy nilly following the human trail.

Under attack at a global level, perhaps the community resilience of Rats will increase, yet their overall resistance will decrease over time. Perhaps their global population will collapse, as it happens to any species that grows beyond the carrying capacity of a given ecosystem. Rats, much like human beings are currently in overshoot. Dare I posit, based on the same model of Overshoot and Collapse, that a similar predicament is in the making for us as well as a species. Yes, our very success (evolution) is proof of our ability to modify ecosystems to our advantage, and we should never forget that too has it’s limits, and many outcomes as favorable and unfavorable.

🐀🌎 🐁 🌍🐀🌏🐁 to ratten resilience!