THE newly fashionable term, the Anthropocene, is a geologically distinct age that defines the advent of the human imprint on ecological systems.¹ As proposed by Crutzen, it begins roughly in the late 18th century, corresponding to the first appearance of carbon dioxide (CO2) and methane (CH4) in trapped air from polar ice cores.² This era coincides conveniently (and perhaps not coincidentally) with the invention of the steam engine in 1784 and the revolutions that followed in its wake. The term, while certainly useful, embodies a profound defeat, an ongoing mass extinction as clear and as dramatic as that other catastrophic geo-logical transition – the KT boundary.

In recognizing the centrality of the human touch to the ongoing sixth mass extinction,³ the Anthropocene confers all humanity with the same destructive power as a planet-destroying asteroid. Regardless of its unquestioned authenticity, it says something semiotically revealing of the environmental scientist’s rather despairing vision of human history. Like the rock that caused the Chicxulub impact, humanity itself in the Anthropocene is conceived as something external, an exogenous (if not strictly extra-planetary) influence, not inherently part of the system. The ‘natural order’ of things does not account for contingencies as large, as messy and as unpredictable as meteorites or, indeed, in the view of environmental scientists, as human history.

The eschatological narrative of conservation activism has its positive counterpart in conservation science that looks in the opposite direction, towards Eden, for its inspiration. Although still founded firmly in its catastrophist roots, conservation science has always been an aspirational, hopeful and purpose-driven enterprise, which is not secular to outcome. Almost by definition, it is a strongly preservationist field, seeking a retreat to a more pristine past. This is clearly an ideological rather than a rational position, and raises valid questions of how appropriate it is for the field to arrogate to itself the same epistemic status as the putatively more value-neutral sciences. Its basic Edenic approach, however, has its foundations in the study of ecology itself.

In our attempt to make sense of the cluttered chaos of natural systems, we conceive of a ‘pure ecology’, untainted by human influence, where we are free to hunt for its general laws and unified theories.⁴ The proper study of ecology, by this reckoning, becomes an examination of species and their interactions, both with each other as well as with their habitats across time and space, in as close to their ‘natural state’ as possible.

 

If these natural states cannot be found in the real world, ecologists are happy to replace them with caricatured versions – with mesocosms (ecosystems in bottles) or with computational models – of idealized ecosystems. While this approach has led to important universal insights on how ecological communities work, it has also contributed to an ecology that belies the existence of humans as valid interactors in the system.⁵ Ecological theory and its aspirations for universality develop in a space separate from and independent of human historical processes. Within this framework, human influence is almost always conceived as an externality, and there has grown a large research programme dedicated to documenting how the human stain corrupts the natural order, leading to the extinction of species, the unravelling of ecological interactions and the destruction of habitats.⁶

It is not surprising then that when ecological theory gets transubstantiated into conservation science, it takes on preservationist hues. As Evan Eisenberg argues, the audacious ambitions of conservation are to reclaim the dream of Paradise.⁷ Our networks of national parks aspire to be reconstructed Edens, complete with its high walls and flaming swords of hermetic protection. A. Starker Leopold, son of Aldo Leopold and a conservation thinker himself, expressed it most explicitly when he wrote in 1963 about his vision for Yellowstone National Park: ‘A national park should represent a vignette of primitive America’, and while acknowledging that ‘restoring the primitive scene is not done easily nor can it be done completely,’ argues that ‘a reasonable illusion of primitive America could be recreated, using the utmost skill, judgement and sensitivity. This, in our opinion, should be the objective for every national park and monument.’⁸

 

What is curious about this construction is that, like Eden itself, it is an attempt to abjure history. Within the boundaries of this Eden, a dynamic stasis prevails in which pure ecology can play itself out, uninfluenced by contingent exogenous forces.⁹ While not exactly negating that history exists (which would be blatantly foolish), the preservationist ideal is one in which it is banished beyond the fenced boundaries of the Protected Area.

 

I will fully admit that what I have outlined is a naive caricature of the preservationist position, but it has important consequences for how we construct the ecologies of the systems we seek to understand and even more profound implications for how we intervene to manage them. I will attempt to explore some of these implications using a case study approach from the marine systems in which I work. Nearshore marine ecosystems in India have always been multiple-use environments, and it has been much more difficult to define spatially explicit and user exclusive tenurial rights over bodies of water than it has been on land. As a result, the strongly preservationist bent of much terrestrial conservation is much less prevalent in marine systems. The understanding and management of marine ecologies, needs must, have had to engage with the dynamic contingencies of historical forces.

Taken together, these examples suggest that history is a critical lens through which we need to interpret the functioning of ecological systems. I explore the potential value of including history as a driving variable in ecological systems, endogenous to, rather than external from the system itself. I also suggest what it may mean to an ecological research programme to embrace this historical lens as a factor while studying species interactions and the human-wildlife interface. I conclude with a few undeveloped questions about our conceptions of the pristine and tentatively ask if it is even possible to envision a more predictive historical ecology.

 

Tropical coral reefs are the canaries of climate change. Ocean warming events associated with a changing climate have resulted in sudden mass mortalities of coral from reefs across the world, triggering ecosystem declines from which recovery is protracted, if it has not completely stalled.¹⁰ In the wake of these climate change events, a depressingly familiar ecological narrative has begun to emerge from reefs around the world. The natural buffer capacity of reef systems has come apart under the unrelenting influence of fishing pressure. With functionally critical herbivores fished out of most developing world reefs, when subjected to coral mass mortality, these reefs are soon taken over by macroalgae. These macroalgae pre-empt space on the reef benthos and prevent coral from recovering. Several decades after the initial coral decline, many reefs have shown very little recovery.¹¹

This universal narrative does not quite fit the Lakshadweep reef system. I began monitoring its reefs in 1998, in the wake of one of the worst El Niño Southern Oscillation (ENSO) events to have affected tropical reefs in recorded history. I recorded a catastrophic die-back of coral across the archipelago in 1998, and have been tracking these reefs ever since. What emerges from this long-term monitoring is a far more complex picture of reef responses to climate change events with reefs following at least three qualitatively different ecological trajectories after these mass die-offs. The mechanisms underlying these trajectories are highly context specific, driven by coral recruitment, herbivore numbers, the architectural stability of the benthos and hydrodynamic patterns.¹²

 

What is interesting about the ecology of the Lakshadweep is the unexpected resilience it apparently shows in the face of potentially catastrophic events. This is particularly surprising given the fact that the Lakshadweep is among the most densely populated parts of rural India with fishing as an economic mainstay. However, what separates the Lakshadweep from many other tropical reef systems is that, despite this large population density, the reefs continue (until recently) to have a very low fishing pressure, making them as close to pristine as is possible to be in human-inhabited island systems.

This was not always the case. Prior to the 1970s, reef fishing was the dominant fishery on the islands, geared largely to meet local requirements. This changed dramatically with the advent of an experimental fisheries development programme conducted by the Fisheries Department to harvest pelagic tuna using a pole-and-line method that fishers in other oceanic islands had been using. This proved to be hugely successful and has weaned fishers off the reef; until today, tuna fishing is the primary fishing practice on the island.¹³ The epiphenomenal upshot of this experiment is that the reefs today have considerably higher resilience than similar reefs across the tropics.

What is critical for our discussion is that if it were not for this single contingent event, the reefs of the Lakshadweep would potentially have had a profoundly different ecology – one that fits much more closely with the common narrative of unravelling ecological interactions being documented in other reefs. It is impossible to make sense of the current ecology of the Lakshadweep except through the lens of its historical influences.

 

What the Lakshadweep reefs show is that a single external event can take ecosystems down very different ecological trajectories. However, historical contingencies more often play themselves out as a series of small events which together amount to large and irreversible consequences for the system. This is essentially what happened with trawl fishing along Indian coastlines. Like the tuna fishery in the Lakshadweep, trawling was introduced as part of a governmental scheme (with the help of the Norwegian government and the FAO) to boost fishery production in coastal waters in the 1960s. The international demand for shrimp fuelled a dramatic rise in this industry, and a rapid overharvesting of the benthos.¹⁴

Since then, however, fishing practices along this coast have been characterized by a dynamic and constantly evolving relationship between the ecological resource, fishing communities and a changing marketplace. The fishery can be seen as an uninterrupted serial depletion of fishery stocks as first shrimp, then squid, then shark, and finally a decaying cornucopia of mixed benthic species are hauled in to keep the industry alive.

Our work shows that fishery is no longer sustained by feeding human demand for fish, but to supply a growing poultry industry with chicken-feed.¹⁵ This reduction fishery is high volume, low income, and ecologically disastrous. On the face of it, it is difficult to make sense of the fishery at all, or understand why and how it continues to persist in the face of declining target catches and profits. It is only when we re-imagine the fishery as a coupled system where local fishers are interactively adapting to a constantly changing ecological baseline and new market opportunities that the rampant overfishing of the East Coast makes sense.

 

The idea that historical contingencies can strongly mediate the trajectories that natural ecosystems take is neither new nor particularly surprising. What is a greater surprise is the dogged blindness of conservation science in light of the self-evident. As the field aspires to move away from the culture of ecological just-so stories towards a more conceptually appealing goal of unearthing transcendent principles of ecological structure and functioning, the field of ecology has had to necessarily ignore the inconvenience of historical contingency when constructing its theoretical models of how the world works. And while this construction is perfectly valid within the framework of a well defined ecological research programme, when carried over as an ideological position to conservation action, it can have unintended consequences, often borne by the ecosystem itself.

 

Sea turtles have been charismatic flagships for marine conservation. According to estimates by Jeremy Jackson, current estimates of green turtle populations in the world’s oceans is a tiny fraction of what it was in pre-Columbian times, and they have succumbed to the combined pressures of overharvesting and habitat degradation.¹⁶ In the last several decades, there have been concerted global efforts to protect and enhance their populations with a raft of management measures including the establishment of rookeries, protection of nesting beaches and the reduction of fishing bycatch. The green turtle is today emblematic of what can be achieved with concerted conservation efforts. While nowhere near the pristine densities estimated by Jackson, green turtle numbers are on the rise in several locations in the Indian Ocean, the Pacific and the Atlantic.¹⁷ The Lakshadweep is one of these locations where, over the last two decades, there has been a dramatic increase in green turtle numbers, among the highest recorded anywhere.

 

Green turtles are herbivores and they depend primarily on seagrass for their forage. In the Lakshadweep islands, we first encountered the green turtle as the antagonist in a bitter conflict with local fishers that used the seagrass meadows to fish. Their claim was that green turtle population increases had precipitated a major decline in their fish catch from the lagoon. In examining the ecological underpinnings of this conflict we found that green turtles were indeed at very high densities and, at these numbers, were significantly overgrazing seagrass meadows causing major changes to growth rates and productivity patterns, resulting in major shifts in the species composition of seagrass, and eventually, to meadow decline.¹⁸ This naturally led to significantly lower fish recruits and adult fish using the meadows. Fishers fishing in meadows occupied by turtles had fish catch values an order of magnitude lower than when turtles were absent.¹⁹ What, on the face of it, looked like a major conservation success had a string of unintended consequences, leading to significant conflict with local communities and ecosystem decline.

This case study presents a compelling paradox about our conceptions of the pristine. At its most basic, it calls into question the past population estimates of large marine megafauna: could Eden have adequately supported and fed the numbers purported to have been in the Garden, or would they, quite literally, have eaten themselves out of house and home? If these populations are indeed representative of pristine numbers, it raises even more complex questions of what a pristine seagrass ecosystem would have looked like. While working towards an ecology of Eden, it is clear that there are inherent contradictions in our Edenic constructions: an Eden for turtles may not be an Eden for seagrass meadows, and certainly not for the people having to share the meadow with turtles.

 

What would it mean to include historical contingency as an endogenous driving factor of ecosystems? At its most fundamental, it would perhaps require us to accept that ecology, like evolutionary biology, is for the most part an inherently historical science. This is not to claim that universal principles of ecology do not exist,²⁰ but that this may require a loosening of the boundaries of that universality and an acceptance that, if a Grand Unified Theory of ecology exists, it is unlikely to be housed under a single equation but may, more realistically be a fairly large family of equations, the choice of which is highly dependent on contingent situations and historical influences. They become predictable only insofar as these historical influences or contingencies are predictable.

Whether it is possible to engage with a more predictive historical ecology is perhaps stretching a very long bow. It may be possible, for instance, to conceive of a set of environmental, geographical, cultural and ecological parameters that together predispose ecosystems to certain historical processes. If this were true, an ecological research programme would include an attempt understand these predispositions, and to fit them into a quasi-testable framework. While it is difficult to conceive what such a research programme would resemble, it would most likely be designed around replicated comparisons between locations that vary in a single driving factor examining the evidence for convergent or divergent histories at these locations. Within this agenda, ecologists would necessarily have to adopt a slightly more post-modern construction of their field, allowing for the idea that there most likely exist several potential ecologies associated with any given ecosystem.

 

A reprise of the story of the green turtles may provide the first hint that this predictive ecology has some merit. What we have documented from the Lakshadweep is now being replicated in several of the world’s seas. In the seagrass meadows of Borneo, the Bahamas, Mayotte Island and Australia, a remarkably similar story to the Lakshadweep is being played out. The global conservation success for green turtles is resulting in potentially disastrous consequences for these seagrass meadows, leading in some extreme cases, of green turtles devastating seagrass meadows beyond thresholds of recovery.²¹

Finally, even if the idea of a formal induction of history into the proper study of ecology is a bridge too far, it still makes sense to view our ecosystems through the lens of human historical use. The high transcendent ideal of ‘pure ecology’, when translated into conservation, works on the assumption that the pristine state is something that is both desirable and achievable. There is very little reason to believe that either is true. The turtle case study underscores the hubris of desirability – the unintended consequences of returning to the pristine can often be worse for ecosystems and their function than we imagine.

An alternative approach requires surrendering one of the central articles of faith of conservation ecology – that there exists ‘out there’ an ideal ecosystem state for managers to aspire to, a state that, in most conservation narratives, existed in a past before humans fell from ecological grace. This nostalgic hankering for a pristine baseline that is in itself dubious in construction, may blinker us from seeing ecosystems as they likely have always been, at least within human timescales – messy, highly stochastic and prone to inevitable surprises and historical accidents.

 

A less ambitious ecological research programme would focus not so much on how ideal systems (that may represent less than 1% of the world’s extant ecosystems) function, but on what is achievable within the untidy coupled human-ecological systems that dominate the globe today. While much less grand in its scope, a conservation ecology built on these principles would, I suspect, advance the cause of conservation much more. It would mean trading in the search for transcendent ecological principles for a more modest, but considerably more pragmatic blue-collar goal of providing a toolbox to sustainably manage the functioning of real world ecosystems.

 

Footnotes:

1. W. Steffen, et al. ‘The Anthropocene: From Global Change to Planetary Stewardship’, AMBIO: A Journal of the Human Environment 40, 2011, pp. 739-761.

2. P. Crutzen, ‘Geology of Mankind’, Nature 415, 2002, pp. 23-23.

3. G. Ceballos, P. Ehrlich, A. D. Barnosky, A. García, R. Pringle and T. Palmer. ‘Accelerated Modern Human-Induced Species Losses: Entering the Sixth Mass Extinction’, Science Advances 1, 2015, e1400253.

4. G. Cooper, ‘Generalizations in Ecology: A Philosophical Taxonomy’, Biology and Philosophy 13, 1998, pp. 555-586; J. Lawton, ‘Are There General Laws in Ecology?’, Oikos, 1999, pp. 177-192.

5. Paul Feyerabend in ‘Against Method’ argues that this curious abnegation of human history is characteristic of all natural sciences, whose programme is to arrive at objective ‘bare facts’, uninfluenced by the vicissitudes of history, culture and creative eccentricity that all strongly influence the ideational foundations on which all theory rests. Feyerabend argues that this is a naïve (if presumptuous) philosophical starting point and proposes a rather more anarchic approach to knowledge-making across all of natural science (P. Feyerabend, Against Method. 4th edition. Verso, New York, 2010).

6. A.D. Barnosky, P.L. Koch, R.S. Feranec, S.L. Wing and A.B. Shabel. ‘Assessing the Causes of Late Pleistocene Extinctions on the Continents’, Science 306, 2004, pp. 70-75; D. Burney and T. Flannery. ‘Fifty Millennia of Catastrophic Extinctions After Human Contact’, Trends in Ecology and Evolution 20, 2005, pp. 395-401; J.A. Estes, et al., ‘Trophic Downgrading of Planet Earth’, Science 333, 2011, pp. 301-306; A.D. Barnosky, et al. ‘Approaching a State Shift in Earth’s Biosphere’, Nature 486, 2012, pp. 52-58. Nature Publishing Group.

7. E. Eisenberg, The Ecology of Eden. Alfred A. Knopf, New York, 1998.

For a detailed discussion of the pursuit for Eden and it’s environmental consequences, see Richard H. Grove’s Green Imperialism: Colonial Expansion, Tropical Island Edens and the Origins of Environmentalism, 1600-1860. Cambridge University Press, UK, 1995. Grove traces the birth of environmental movements in the wake of the dramatic changes wrought by colonial powers in their search and subsequent modification of ‘pristine’ tropical paradises.

8. A.S., Leopold, S.A. Cain, C.M. Cottam, A.N. Gabrielson and T.L. Kimball, Wildlife Management in the National Parks: The Leopold Report. The National Park Service, 1963.

9. There is a large research programme that views ecosystems as inherently non-equilibrium systems where natural disturbances, more than any other biotic or ecological processes are the dominant structuring agents of ecosystems – making them essentially non-deterministic and unpredictable. None of this body of work diminishes the arguments in this paper. For one, these theories still seek their universality independent of human historical processes. For another, conservation ecology, for the large part, is built strongly on the more teleological foundations of ecosystems as self-contained, dynamically homeostatic systems; healthy ecosystems in this conception, when properly conserved, are resilient to change.

10. T.P. Hughes, et al., ‘Climate Change, Human Impacts, and the Resilience of Coral Reefs’, Science 301, 2003, pp. 929-933.

11. N.A.J. Graham, S. Jennings, M.A. MacNeil, D. Mouillot and S. K. Wilson, ‘Predicting Climate-Driven Regime Shifts Versus Rebound Potential in Coral Reefs’, Nature, 2015, pp. 1-17.

12. R. Arthur, T. J. Done, H. Marsh and V. Harriott. ‘Local Processes Strongly Influence Post-Bleaching Benthic Recovery in the Lakshadweep Islands’, Coral Reefs 25, 2006, pp. 427-440.

13. R. Arthur, Patterns and Processes of Reef Recovery and Human Resource Use in the Lakshadweep Islands, Indian Ocean. School of Tropical Environment Studies and Geography, James Cook University, 15 April 2005.

14. A.S. Lobo and R. Arthur, ‘Trawling the Shorelines: Fished Out and Squandered’, in M. Rangarajan, M.D. Madhusudan and G. Shahabuddin (eds.), Nature Without Borders. Orient Blackswan, New Delhi, 2014. pp. 41-57.

15. A. Lobo, A. Balmford and R. Arthur, Commercializing Bycatch can Push a Fishery Beyond Economic Extinction. Conservation Letters, 2010.

16. J.B.C. Jackson, ‘Historical Overfishing and the Recent Collapse of Coastal Ecosystems’, Science 293, 2001, pp. 629-637.

17. A.C. Broderick, R. Frauenstein, F. Glen, G.C. Hays, A.L. Jackso, T. Pelembe, G.D. Ruxton and B. J. Godley, ‘Are Green Turtles Globally Endangered?’ Global Ecology and Biogeography 15(1), 2006, pp. 21-26.

18. A. Lal, R. Arthur, N. Marbà, A. W. T. Lill and T. Alcoverro, ‘Implications of Conserving an Ecosystem Modifier: Increasing Green Turtle (Chelonia mydas) Densities Substantially Alters Seagrass Meadows’, Biological Conservation 143, 2010, pp. 2730-2738; N. Kelkar, R. Arthur, N. Marbà and T. Alcoverro, ‘Green Turtle Herbivory Dominates the Fate of Seagrass Primary Production in the Lakshadweep Islands (Indian Ocean)’, Marine Ecology Progress Series 485, 2013a , pp. 235-243; N. Kelkar, R. Arthur, N. Marbà and T. Alcoverro, ‘Greener Pastures? High Density Feeding Aggregations of Green Turtles Precipitate Species Shifts in Seagrass Meadows’, Journal of Ecology 101, 2013b , pp. 1158-1168.

19. R. Arthur, N. Kelkar, T. Alcoverro and M. D. Madhusudan, ‘Complex Ecological Pathways Underlie Perceptions of Conflict Between Green Turtles and Fishers in the Lakshadweep Islands’, Biological Conservation 167, 2013, pp. 25-34.

20. J. Lawton, 1999, op. cit., fn. 4.

21. M.J.A. Christianen, et al. ‘Habitat Collapse Due to Overgrazing Threatens Turtle Conservation in Marine Protected Areas.’ Proceedings of the Royal Society of London. Series B: Biological Sciences 281, 2014, 20132890-20132890; M.R. Heithaus, et al., ‘Seagrasses in the Age of Sea Turtle Conservation and Shark Overfishing’, Frontiers in Marine Science 1, 2014, pp. 1-6.