Published 28 August 2019
In the early 2000s, a series of corvid heists took placeat the Membury service station on the M4 motorway in England. In each case, events unfolded in pretty much the same way. Two rooks (Corvus frugilegus) arrived and took up positions on opposite sides of the top of a garbage can. Working in tandem, they pulled the plastic liner up with their beaks, securing it at this new height with their feet before reaching down again with their beaks to pull it up further. Repeating this action about twenty times, the birds gained access to the once inaccessible waste at the bottom, bringing it ever so gradually within beak’s reach.1 Many of the remarkable behaviors that went into this heist — teamwork, patience, and calculation —have been experimentally demonstrated by corvids over the years.2
It isn’t entirely clear that anything was really being “stolen” in this case: can one really steal what another has discarded? But there is an important act of theft lingering at the edges of this action. When the garbage was finally within reach of the rooks’ beaks, reports indicate that one of the birds would start tossing the food over the side of the bin while the other, or perhaps a third rook, stood guard on the ground to ensure that the hard-won food wasn’t stolen by others. The real site of potential theft took place after the elaborate heist, once the food had been secured. Here, in this seemingly mundane, everyday space of encounter — crows squabbling over bread or a chip on a sidewalk — a great deal of what it means to be a corvid takes shape. As these rooks diligently guarded their bounty they demonstrated both the capacity to anticipate theft by others and the ability to act preemptively to ward it off. This, too, is no small achievement; in fact, it may even be the case that these pilfering and antipilfering activities are in some sense fundamental to what it is to be a corvid.
Here in this seemingly mundane space — crows squabbling over bread or a chip on a sidewalk — a great deal of what it means to be a corvid takes shape.
Most crows, it seems, spend a solid amount of time each day stealing from others. Most crow species combine foraging, hunting and collecting activities with efforts to steal food from their neighbors.3 Northwestern crows (C. caurinus) in Washington State steal rather indiscriminately from relatives and strangers, although they seem to tailor their thieving strategies. When stealing from a more closely related bird, a crow often quietly approached and took the food, whereas when a less closely related bird was the target, theft often involved a noisy, squawking approach and a subsequent pursuit until the fleeing bird dropped the food.4 In this context, crows are primarily stealing from others opportunistically, as the food was procured. But, importantly, corvids don’t limit themselves to this kind of theft. In addition, they have become highly skilled at raiding one another’s “caches,” that is, the little bits of food and other items – acorns and other seeds, bits of meat or even tools for extracting grubs from logs and tree trunks – that all species of corvids tend to hide away for later.5
With all this stealing going on, it makes sense that corvids try to cache things away from prying eyes, and if they are seen, they often return later to move the item to a safer location. These are complex cognitive and social operations. It seems that corvids are not only keeping track of their own caches but also of which other birds saw them cache which items where.6 7 Interestingly, an experiment with scrub jays (Aphelocoma coerulescens) showed that only birds who had themselves previously stolen from others took these kinds of preventative actions.8 In short, as Nicola Clayton, professor of comparative cognition at the University of Cambridge, put it in our conversation, “it takes a thief to know one.”
Many of these studies of caching behavior are, more accurately, studies of stealing: of pilfering and antipilfering strategies. This topic has been of particular interest to biologists not because they have a strong interest in questions of corvid morality but because of what crows might here reveal about their ability to attribute mental states to others, referred to in biology as possessing a “theory of mind” (ToM). In acting in the ways that they do, crows seem to demonstrate an understanding of other crows as mindful beings, subjects with their own unique “perceptions, attentions, intentions, and beliefs”.9 Far from simply responding to where another bird is looking or going (“reading behavior”), recent studies strongly indicate that these birds are attributing mental states to others, as demonstrated in work in which ravens took preventative measures to stop pilfering by birds they could not see but knew might be watching them.10
Two of the main laboratories engaged in studying these complex interactions between pilfering and antipilfering —that of Nicola Clayton and that of Thomas Bugnyar at the University of Vienna —have reached a similar conclusion: this behavior may be the key driver in the evolution of the remarkable intelligence of corvids.11 12 Central to this possibility is the development of spatial and observational memory, which allow birds not only to relocate their own caches but to watch where someone else has cached, remember the location, and return later. As Clayton explained to me: “Observational memory for caches has probably driven the increasing cognitive complexity of both stealing strategies and cache-protection tactics, because an individual bird is both the protector of its own caches and a potential pilferer of others”. As Bugnyar and Kotrschal put it: “this competitive game for food may fuel an intraspecific evolutionary arms race for deceptive and cognitive abilities”.13
This fascinating hypothesis places hiding and, of course, stealing at the center of our stories about how it is that crows became who they are. If Clayton and Bugnyar are correct, then perhaps it is pilfering and its prevention that have, more than anything else, enabled their complex cognitive and social lives. Corvid wakefulness is, at least in part, a product of and a preparation for theft—it is stolen property. Stealing is at the core of who crows are. In fact, the more I learn about these activities, the more comfortable I am labeling them as “theft”. While this term surely has a variety of meanings and associations within diverse cultural, not to mention biological, contexts, it seems to me that it is not right to assume that to apply it to the activities of nonhumans is necessarily an anthropomorphic projection. We are, at the very least, in the same neighborhood here. Crows do seem to have a sense of theft: they understand and negotiate its social intricacies, its hostilities and niceties, its conduct and its prevention. They steal knowingly, deliberately, sometimes even carefully—certainly from one another but perhaps also from others, including humans. In making this point, my aim is not to slip into the unhelpful forms of moralizing that so often accompany discussions of theft. Rather, it is to learn to see and appreciate in new ways what is at stake, what is made possible, by stealing. Whole modes of life—fascinating, rich, intelligent ways of being—have been stolen into existence, brought into our world in no small way through this particular space and practice of being with others.
Excerpted from The Wake of Crows by Thom van Dooren Copyright (c) 2019 Thom van Dooren. Used by arrangement with the Publisher. All rights reserved.
The Wake of Crows: Living and Dying in Shared Worlds will be published by Columbia University Press in October 2019.
Crows can be found almost everywhere that people are, from tropical islands to deserts and arctic forests, from densely populated cities to suburbs and farms. Focusing on five key sites, The Wake of Crowsis an exploration of the diverse and entangled lives of humans and crows, asking how we might live well with crows in the midst of ongoing processes of globalization, colonization, urbanization, and climate change. The substantive chapters of the book focus on human/crow encounters in specific sites, in an effort to imagine and put into practice a multispecies ethics for this time of extinction and extermination.
Throughout the book, a series of short vignettes, like the one above, offer reflections on some of the remarkable features of crow life. Drawing on research in behavioural biology, alongside interviews with leading scientists and visits to key labs, these vignettes explore what crows might be up to when they experiment with cars as a means of opening tough nuts (“Experimenting”), when they steal from each other (“Stealing”), when they pull a string together to access food (“Cooperating”), when they hold their wings open over a lit cigarette (“Fumigating”), and when they seemingly leave shiny trinkets for friendly people (“Gifting”). In each of these cases, we learn a little more—or at the very least are provided with some fascinating sites for careful speculation—about how corvids make sense of the world.
Alongside the cited materials, this account draws heavily on an interview with Nicola Clayton, conducted by the author at Cambridge University on May 19, 2017.
1. Clayton, Nicola, 2015. “Ways of Thinking: From Crows to Children and Back Again.” Quarterly Journal of Experimental Psychology 68:209–41. Pp 229
2. Heinrich, B., and T. Bugnyar. 2005. “Testing Problem Solving in Ravens: String‐Pulling to Reach Food.” Ethology 111:962–76.
3. Robinette Ha, R., P. Bentzen, J. Marsh, and J. C. Ha. 2003. “Kinship and Association in Social Foraging Northwestern Crows (Corvus caurinus).” Bird Behavior 15:65–75.
5. Klump, B. C., J. E. M. V. D. Wal, J. J. H. S. Clair, and C. Rutz. 2015. “Context-Dependent ‘Safekeeping’ of Foraging Tools in New Caledonian Crows.” Proceedings of the Royal Society B: Biological Sciences
6. Bugnyar, Thomas. 2010. “Knower-Guesser Differentiation in Ravens: Others’ Viewpoints Matter.” Proceedings of the Royal Society B, Published: 1–7.
7. Heinrich, B., and T. Bugnyar. 2005. “Testing Problem Solving in Ravens: String‐Pulling to Reach Food.” Ethology 111:962–76.
8. Emery, N., and N. Clayton. 2001. “Effects of Experience and Social Context on Prospective Caching Strategies by Scrub Jays.” Nature 414:443–46. Pp 443.
9. Bugnyar, T. 2007. “An Integrative Approach to the Study of ‘Theory-of-Mind’-Like Abilities in Ravens.” Japanese Journal of Animal Psychology 57:15–27. P 15
10. Bugnyar, T., S. A. Reber, and C. Buckner. 2016. “Ravens Attribute Visual Access to Unseen Competitors.” Nature Communications 7:1–6.
11. Dally, J. M., N. S. Clayton, and N. J. Emery. 2006. “The Behaviour and Evolution of Cache Protection and Pilferage.” Animal Behaviour 72:13–23.
12. Bugnyar, T., and K. Kotrschal. 2002. “Observational Learning and the Raiding of Food Caches in Ravens, Corvus corax: Is It ‘Tactical’ Deception?” Animal Behaviour 64:185–95.
13. Ibid. Pp193
Thom van Dooren is Associate Professor and Australian Research Council Future Fellow (2017-2021) in the Department of Gender and Cultural Studies, and founding co-editor of the journal Environmental Humanities (Duke University Press). His research is based in the broad interdisciplinary field of the environmental humanities, with particular grounding in environmental philosophy, cultural studies, and science and technology studies. His research and writing focuses on some of the many philosophical, ethical, cultural, and political issues that arise in the context of species extinctions and human entanglements with threatened species and places. He is the author of Flight Ways: Life and Loss at the Edge of Extinction (2014), The Wake of Crows: Living and Dying in Shared Worlds (2019), and co-editor of Extinction Studies: Stories of Time, Death, and Generations (2017), all published by Columbia University Press.