The Pacific or Polynesian rat (kiore) is the smallest of the three rats (Rattus rattusR. norvegicus, and R. exulans) closely associated with humans. Image credit: Wikimedia Commons

From the time of their arrival in the 1760s, Europeans compulsively characterized the environment they encountered in Aotearoa/New Zealand for its strangeness and depauperization—that is, for what it seemed to lack. Early visitors and migrants were perplexed by what they perceived as the niche-shifts that caused birds to act like terrestrial mammals, insects to scavenge like rodents, bats to dwell on the ground, penguins to inhabit forests, and so on. In practice, these so-called deficiencies served as “enabling absences,” justifying large-scale efforts to stock the country with free-range protein and game, livestock, service animals for use in agricultural development, and creatures that were missed for sentimental reasons. Moreover, the “inevitable” future-absence of endemic species and indigenous peoples was anticipated as part of the graft of settlement—the concerted work that would involve European settlers grafting their own imported lifeworld over an existing one.

Not all creatures brought to Aotearoa/New Zealand by European newcomers, however, were deliberately consigned as cargo. When Europeans made landfall, they also carried with them the ship rat (Rattus rattus) and Norway rat (Rattus norvegicus). As “hitchhikers” or “stowaways” who self-selected to live on board ships, these creatures have conventionally been considered an inadvertent introduction. In her history of acclimatization in Aotearoa/New Zealand, Joan Druett describes them as a “little accident” or an “accidental intruder.” Yet because rats are proximally itinerant and pragmatically commensal—seeking to live close to humans and their food stuffs and refuse—their company would have been expected by European voyagers. In the event of European intervention in the Pacific, the introduction of northern-world rats was more likely to happen than not. In this sense, the geography and “opportunity” that they mirror and trace are profoundly human ones. 

On the basis of their adaptability, fecundity, and characteristic drive to explore unfamiliar surroundings, the two European types of rat fast gained foothold in Aotearoa/New Zealand, producing far-reaching impacts. Because these creatures were already known to European culture and because they command little respect, however, they were not a primary focus of attention. As a result, they generated considerable confusion in the European record. Commentators could not be sure whether the rats they sighted in Aotearoa/New Zealand were newcomers or the long-established kiore or Pacific rat (Rattus exulans). While anchored in Tōtaranui (Queen Charlotte Sound) on Cook’s second voyage, for instance, the German naturalist Georg Forster observed “immense numbers of rats on the Hippah rock, so that [Furneaux and his men] were obliged to put some large jars in the ground, level with the surface, into which these vermin fell during the night, and a great number of them were caught in this manner.” Forster went on to surmise: “It is therefore very probable that rats are indigenous in New Zealand, or at least that their arrival there is prior to its discovery by European navigators.” Yet, as Elsdon Best notes in Forest Lore of the Maori, kiore do not tend to swarm in hordes around human dwellings as described by Forster. What Cook’s crew was encountering in this case was likely the progeny of European rats which had escaped during Cook’s earlier voyage. Best explains: “It is now quite clear that certain persons who have written on these matters confused [R.] rattus with the old native kiore, and so infected others with that confusion.” 

From the start, then, kiore slipped into the European record. This is both symptomatic of—and a point of origin for—the kiore’s ongoing problems of recognition in Aotearoa/New Zealand, which can be mapped in two distinct ways. First, the kiore both is and is not an animal of the place. Best’s use of the term “native” is noteworthy, given his knowledge that kiore had been acclimatized in Aotearoa/New Zealand centuries earlier by Pacific peoples. As Best explains, “The word kiore as a name for the rat is known far and wide across Polynesia.” Stories handed down through iwi and hapu tell that kiore were brought to Aotearoa/New Zealand as a food source and delicacy. According to Best, “The variety of sweet potato known as kakau was placed on the vessel [the waka Aotea], as also were the kiore [rat], the swamp hen, and seeds of the karaka tree, hence the famed saying Aotea utanga nui, or Aotea of the important freight.” In some recorded tribal traditions, this story has become fused with the biblical Noah story, telling of an ark seeding a new world; in other traditions, kumara, kiore, and people are traced to a common ancestor. Kiore, then, are taonga tuku iho or treasures passed down through generations, which makes them unlike other mammals subsequently introduced to Aotearoa/New Zealand. To mistake them for northern-world rats—and vice versa—is to obscure their role in te ao Māori as distinguished travel companions who recall migratory pathways, Pacific homelands, and shared genealogies. 

The second problem of recognition is that from the beginning of European settlement, kiore have been vilified on the basis of northern-world knowledges and cultural memories. As is made plain by Forster’s instinctual use of the term “vermin” and the European voyagers’ instinctual urge (or sense of “obligation”) to exterminate these creatures, rats of all varieties are dismissed by settler culture as being plague-like, dirty, disease-ridden, destructive of agricultural development, “aggressive” and “truculent” and disposed towards sewers, rubbish, and refuse. In this way, kiore have long been infected by settler revulsion towards them and by a lack of settler knowledge about them. As Best hints, “infection” describes the properties of settler knowledge and settler memory more than it does the properties of rats. 

The more recent arrival of kiore as a target of Predator Free 2050 emerges from this history. It would be misleading to imply that the kiore’s acclimatization in Aotearoa/New Zealand has been without difficulty. While this creature is arboreal and largely frugivorous, commentators have disagreed as to its impacts. Reviewing the existing literature, Kazimierz Wodzicki maintained in 1950 that kiore had never established themselves in Aotearoa/New Zealand in any great numbers and that there were no reports of kiore having eaten food of animal origin. More recent commentators, however, hold that kiore consume insects and eggs, and that fossil records implicate kiore in the decline and extinction of a number of birds, lizards, and invertebrates—including the disappearance of formerly-widespread tuatara from the mainland. What is broadly agreed is that kiore declined soon after European arrival owing to direct competition with and predation by introduced fauna, and were believed to have “succumbed” altogether by the mid-to-late nineteenth century. 

These elements of the kiore’s story call forth a version of the replacement-of-species that was a pre-programmed outcome of colonial settlement. As Hori Ropiha of Waipapa lamented in the 1890s, “The native rat is now extinct ; it has been exterminated by the European rat […] just as the birds of New Zealand have been lost through the introduction of European birds.” In the mid-twentieth century, however, remnant populations of kiore were discovered in South Westland and Fiordland and on scattered offshore islands. At this juncture, the kiore’s story might have taken another turn: this creature might have been redeemed as a newly-beloved icon of conservation, enjoyed high-profile programs of special protection, and so on. Yet, as outlined above, settler culture is not inclined to envision rats as worthy recipients of conservation efforts, and kiore are deemed non-endemic because they are not originally from Aotearoa/New Zealand. Moreover, rats are broadly understood by settler culture to harm endemic nature, serving as “the forerunner of a mammal-driven reign of change.” As the threatened species ambassador for the Department of Conservation (DOC) has put it: 

The moment that the first kiore leaped off a waka and scuttled up the beach […] time started to run out for many of our most beloved species. Some 600 years later when our European ancestors made it to New Zealand, the onslaught of mammalian invaders they brought with them would prove to be a tide of teeth that might not have been turned back.

Indeed, the eradication of rats from Ruapuke (Maria Island) in the Hauraki Gulf in 1964 in order to create so-called “predator-free habitat” has come to be understood as a touchstone moment in national and global conservation biology. In 1995, DOC released a strategy which noted that while kiore are “uncommon” in Aotearoa/New Zealand, kiore and other rodents would be actively eliminated from reserves administered by the department. Despite their own endangered status and their role as a taonga species, then, kiore have become a target for ecological clean-up. Or, to put it another way, kiore have accidentally hichhiked into a history in which they are a mis-remembered object. 

Excerpted from “Stowaway Memory” by Anna Boswell. It was originally published, in a slightly different format, in Pacific Dynamics: Journal of Interdisciplinary Research (November 2018, Vol. 2 ) and is reprinted by permission of the author.

This essay is part of a spring 2023 Public Seminar special issue on rats, curated by senior managing editor Evangeline Riddiford Graham.

Anna Boswell is a writer and scholar living in Aotearoa/New Zealand.