Saturday, December 17, 2011

The Status Quo is Never Ante

In a nice piece, "How to Be Manipulative", (sorry, paywall) describing how ecologists can manipulate or observe manipulated ecosystems to learn about how they behave, Robert Pringle talks about how megafauna is being returned to the Gorongosa national Park in Mozambique. Established by the Portuguese in the 1920s the park was severely impacted by the civil war. Today the government wants to reestablish the ecosystem to attract tourists.

The human suffering was immense. But Gorongosa"s unraveling was tragic in its own right, in part because eco-tourism represented one of the few pathways to sustainable development in a decidedly underdeveloped country.
Pringle deals at length with the issue of what should be the end point for restoration, and indeed what restoration means
...consider some of the immediate practical questions facing the Gorongosa Restoration Project. Choosing a baseline by which to define success in restoration requires decisions that affect both people and wildlife. For logistical reasons, 1975 would represent a plausible baseline. That was the year Mozambique gained independence, and we have excellent quantitative data about the state of the ecosystem in the late 1960s and early 1970s. But if we choose 1975, we confront difficult questions. As of late 2011 there are several thousand people living within the park. Should they stay? If so, how many, and on what terms? Human settlements are anathema to many old school conservationists, but others are quick to point out that an African savannah sans Homo sapiens is a very artificial thing indeed. Humans have inhabited Gorongosa for almost as long as there have been humans, hunting, gathering, farming and fishing. It was the Portuguese who imported the notion of a national park without people, transforming hunters into poachers and farmers into squatters The humanitarian implications of forcibly re-evicting a large population of poor people from the reborn national park demands serious scrutiny (and is, in fact against park policy).
Whatever the evidence for human-wildlife coexistence prior to imperial conquest there is little reason to assume that it would be stable today in the absence of limits on population growth and livelihood activities. What limits are sustainable? Are they ethical? How should the government weigh the access rights of today's population against anticipated economic growth and the quality of life of future generations/

Likewise for wildlife: What composition of species and confiuration of habitats should the park engineer, and how actively and aggressively must the landscape be managed to obtain that outcome? If we plan a return to 1975, do we then write off the two antelopes - roan and tsessebe - that went extinct prior to 1970 (with an assist from European hunters). White rhinos were extirpated around 1940 but reintroduced in 1970 and cheetahs were reintroduced in 1973. Theoretically, moving our baseline forward or backward a few years would dictate whether these spectacular species should be re-introduced or not.

And then there is the brain-bending question of zebras. The park needs zebras for several reasons: They are a tourist draw; they are food for lions which are an even bigger tourist draw; and they are bulk grazers that would help open up the rank and overgrown grasslands, which in turns would likely increase plant productivity and diversity and reduce the heat and intensity of dry-season fires. The problem is that Gorongosa lies at the biogeographical interface of what some authorities consider two distinct subspecies of zebra. Equus quagga crawshayi to the north and E. q. chapmani to the south.
Here the choice is to take forever repopulating with the remnants of the zebra herd in the park or bring in those of a "slightly different stripe" from nearby countries
This is a problem with no optimal solution. Resolution hinges on the relative values assigned to an ostensibly unique subspecies on the one hand and the urgency of restoring ecosystem function and touristic viability on the other. Again, we are forced to ask: What exactly are we trying to salvage and what are we trying to restore? In a world of limited resources, limited time and limited zebras , what are our priorities? Opinions differ and emotions run strong.

The upshot is this: Restoration in any rigid and consistent sense of the word is impossible. the best we can do is approximate some prior state of any give ecosystem and the approximation we work toward will reflect both the values of the people directing the effort and the inevitable limitations of knowledge and capacity. On top of all that, there is no guarantee of getting what we aim for. Our predictive tools are not sophisticated enough . . .
Pringle concludes that restoration is reimagination and that is liberating
If what we are doing is imagining and creating then we can be imaginative and creative and that is exciting. How should our garden grow? . . . Who are the clients, what do they need and what do they want and which blueprints fuse needs and wants into something truly beautiful?


David B. Benson said...

The more diverse the better.

John N-G said...

Left unmentioned is the fact that the climate in Mozambique in 2011 is different than the climate in 1975, and the climate in 2051 will be much more different. The 1975 ecosystem may not be viable past 2051. Restoration is a pipe dream.

Anonymous said...

I sort of agree with John N-G, but I still think it a worthwhile project. However, flexibility will be needed. Rigid thinking could be the death of the project.

A fully functional diverse ecosystem should be far more resilient than the extreme mono-cultures we do.

Little Mouse

Fixed Carbon said...

In response to, "an African savannah sans Homo sapiens is a very artificial thing indeed. Humans have inhabited Gorongosa for almost as long as there have been humans, hunting, gathering, farming and fishing.."
there are two key points,
how many H. sapiens before, say 1700?
what were their techonologies. While H. sapies of pre-European colonial times were in the iron age, the sophistication of their uses of iron was not great.

Jim Bouldin said...

This raises the same two questions that any restoration attempt now raises:
1) What is the desired target condition?, and
2) How big of an impact should humans have on the system?

W.r.t #1, John N-G hits the nail exactly when he talks about climate change. Whether Mozambique's climate is now markedly different from 1975 I don't know, but it will very likely be different at some point in the future. How different we do not know, which is the case everywhere, which is why we need continually improving global and regional climate prediction models.

W.r.t. the zebra subspecies interbreeding issue, although I don't know the specifics of the population sizes and genetic differences, that issue has got to be considered well down the list of important things to consider here. Preserving subspecies "purity", if that's the concern, must take a backseat to long term system stability.

I think Pringle's closing statement is right on. It's very important not to let the vision die. I think that's probably what drives Dave Foreman's "rewilding" dream. The question is how sane and accomplish-able is the vision.

Anonymous said...

Dr. Jay Cadbury, phd.

Pringles make for an excellent stocking stuffer, along with coal.