Last chance to see… the world that our Ancestors saw
What would you do if…
you read that a big multi-national company was to clear-fell some 10% of South
Africa’s Afromontane forest due to the rarity value the timber fetches on the
global markets, or that China has decided that it wants to cull 10% of the
remaining panda population to provide a culinary delicacy for an elite few or that
Australia has decided that it can harvest 10% of its great barrier reef to supply its
burgeoning tourist market with cheap coral mementos. These scenarios are
obviously outrageous, forests, pandas and coral reefs are conservation icons.
However, there are many species and now entire ecosystems that are literally on
the brink of extinction. Recently, while watching David Attenborough’s series
“State of the Planet”, I was alarmed that to illustrate habitat loss linked to species
extinction he used Lowland Fynbos around Cape Town. On reflection, is there a
global biodiversity hot spot so rich and yet so perilously close to extinction? In
becoming high priests of profit modern society is causing entire ecosystems to be
knocking on the proverbial pearly gates? What are the conservation planners
doing and is it a case of too little too late?
The Ten Percent Capital Rule
The IUCN (World Conservation Union) recommendations for conservation
management, is to set aside at least 10% of each respective ecosystems within a
national protected areas network. This 10% was to be applied by each nation,
including South Africa, who was a signatory to the Convention on Biodiversity.
Why is 10% considered to be the magical number? This seems to relate to
hypothetical calculations derived from colonization and extinction of islands,
where 90% of the species can still be maintained on 10% area. Some ecologists
have argued that ecosystem integrity becomes compromised with a 60% loss of
area. This 10% numeric has become fixed in policy frameworks world-wide.
However, some species are able to avoid extinction even though their numbers
remain low, whereas other species become extinct rather easily, and further it
appears that rare species resist extinction with smaller population sizes than
common species. The demise of the Passenger Pigeon is the best illustration,
which went from being the most numerous bird species to extinct within two
decades, simply because it had become “fun” to shoot.
Many of these theoretical considerations are based on evenness in the
distribution of species or vegetation types in a landscape, but we have common
and rare species and vegetation types that are differently distributed (often
clumped or naturally fragmented. A species or vegetation type that is naturally
rare or highly clumped is usually able to survive with lower representation than a
widespread and common species which has experienced a considerable loss by
area.
Often naturally fragmented and uneven distribution of species and vegetation
types is the result of disturbances, both natural and human-induced. Although
the term disturbance may sound bad, like fire (often reported as “destroying”
fynbos) it actually provides opportunities to rejuvenate a species or a vegetation
type. Fynbos is quite literally a phoenix and without fire it becomes senescent
and its species richness declines. Grasslands, if they are not grazed by animals
or periodically burnt may also become dominated by a competitive few with a
loss of rarer species. Consequently many species occurrence and ecosystem
forms have literally been molded by past events, which are infrequent to random
in their occurrence. Such uncertainties within systems of chaos makes natural
habitat management difficult, especially as animals move and plants simply hide
their presence by way of seed banks in the soil. Failure to recognize that species
are cryptic in their occurrence within an ecosystem has made it very difficult for
ecologists to accurately state which species do and do not exist within a natural
habitat. This is illustrated by the rare species of Priestleya which appeared after
some 50 years of absence when a pine plantation on Table Mountain was
cleared or the re-discovery of Channel-leaf Featherbush - Aulax cancellata once
also locally common on this mountain.
Species occurrence within a vegetation type or an ecosystem is influenced by the
presence of other species and a variety of interactions such as competition
between plant species and between animal species, through to facilitation where
plants may use other plants, like a vine using a tree to reach for the sun. Plants
and animals also interact with each other and animals aid sedentary plants with
pollination and seed-dispersal services. Nevertheless as more natural habitat
yields to insatiable human pressures for development, species are becoming
increasingly isolated and restricted to their small islands of natural habitat, their
relationship with each of their associates becoming compromised with inevitable
species loss and ensuing extinction.
Death Match: West Coast Renosterveld versus Sandplain Fynbos
West Coast Renosterveld, Sandplain Fynbos and Coastal Thicket all make up
the vegetation of the Cape Lowlands. The Coastal Thicket is largely derived
from the Subtropical East Coast and occurs on dune sands which are alkaline in
character. Both the Renosterveld and Sandplain Fynbos are floristically species
rich and most of this floral richness occurs nowhere else (termed endemism).
Sandplain fynbos occurs on the nutrient poor and older more leached sands that
are acidic in nature. Like its cousin the Mountain Fynbos it has proteas, heaths
(including ericas) and Cape reeds (Restio) as the dominant species. It is a
vegetation type that requires burning periodically (12-15 years) but also has a
conspicuous annual and geophyte presence. It is likely that low nutrients have
prevented groups like the grasses from being more dominant, however, if
Sandplain Fynbos becomes disturbed, invasive alien grasses are quick to
encroach and difficult to eradicate. Rainfall in Sandplain Fynbos is generally
much lower than in Mountain Fynbos and usually below 700mm per annum.
West Coast Renosterveld occurs on the more nutrient rich and heavier shales
with high clay content, so little of it is left that there is debate as to exactly what
its ecological nature was? It is generally considered to be a shrubland-grassland
mixture. Historical accounts of early travelers indicate that most of the big game
such as Lion, Buffalo, Hyena and Eland occurred in these habitats. The role of
fire in Renosterveld has been debated but essentially with animal grazing would
have been important in maintaining and shaping plant communities. The fertile
soils which supported West Coast Renosterveld have largely been transformed
by agriculture, most notable wheat in the past and vineyards today.
Sand Plain Fynbos and the West Coast Renosterveld are estimated to be about
70% and 90% transformed, leaving rather little left to start the process of
conserving it. Unfortunately, these statistics, rather than being hard facts vary
with interpretations and methods of determination. Firstly, the original
distribution of these two vegetation types prior to human disturbance can only be
deduced from early traveler’s journals together with inferring climate and soil
characters. Even the term West Coast Renosterveld is ambiguous but expert
consensus agrees that precious little of the lowlands are left, especially close to
the City of Cape Town, and this may not be representative of what previously
existed. Modern earth observing satellite images are useful for showing land use
trends, but to translate these images into meaningful maps is difficult. Some
transformed land uses such as wheat fields are easily mapped but encroachment
of suburbia or the invasion of natural vegetation by woody alien species is
problematic especially since accessible low-cost imagery is low resolution (only
highway-size features are discernable).
If we focus on a smaller area where detailed and geo-corrected photography is
available like Greater Cape Town we can get very accurate estimates of what is
remaining and it is possible to visit and assess these sites so the condition can
also be determined. On these lowlands there are about 1500 species, 76 of
which are endemic and 131 rare and endangered species. Here we have only
1% of the Cape Flats Sandplain Fynbos and 3% West Coast Renosterveld
conserved, and for neither of these vegetation types can you achieve the desired
conservation targets. Consequently all sites with these vegetation types are
referred to as irreplaceable and form the basis for defining a vegetation type that
is critically endangered and under the new EIA regulations of National
Environmental Management Act (NEMA). Under this act any removal of a
critically endangered vegetation type will require an environmental impact
assessment.
Using our death match analogy the Cape Flats Sand Plain Fynbos is most likely
to be the first loser, due to its low formal conservation. Further, precious little is
left and it is easily disturbed through nutrient enrichment. There is concern that
even car exhaust emissions of nitrous oxide could increase soil nitrogen levels
through precipitation, essentially acid rain. In contrast, Renosterveld occurs on
nutrient rich substrates so should be less sensitive to nutrient loadings from
human resources, and recent research suggests that fire has less of a role for
maintaining its species richness but browsing and grazing by animals is
important. Climate Change and especially elevated CO2 is considered to be
another atmospheric fertilizer that will promote weedy species and consequently
it could be expected to have more of an impact on the nutrient-poor Sandplain
Fynbos. Other studies have suggested that in Renosterveld, small patch sizes
do lead to a breakdown in services like pollination. Sandplain Fynbos will
undoubtedly be similar.
Conservation Planning: A Pandora’s Box of Algorithms
Despite a lack of precision knowledge of what occurs where and in what
condition, sophisticated numerical techniques have been developed which use
species and vegetation types to maximize the biodiversity capital (even if it is
only 10%) so as to be used for maximum benefit. These “optimized” solutions
identify which remaining sites conserve the most representatives of species or
vegetation types. There are a plethora of algorithms to calculate these solutions
which most often use the rarest site or rarest vegetation type to start the
prioritization. A few algorithms even use the proximity of similar natural habitat
so as to configure solution that minimizes the distance plants and animals have
to move from one remnant to another. Yet others take into account the geometry
of the remnant patches and determine that circular areas will be better than
elongated shapes, and this is based on minimizing edge effects, which usually
experience higher disturbances. Without adding layers of information on human
use for integration such as the use of biodiversity planning corridors this
approach will only permit write-off of natural sites to provide the most amount of
land for development.
Unfortunately our two lowland vegetation types Sandplain Fynbos and West
Coast Renosterveld present another problem for their systematic conservation:
they pack almost the most number of species into the smallest footprint
anywhere in the world, and their species composition changes across the
landscape at rates unmatched. This means that the same type of vegetation can
have very different species composition within a comparatively short distance.
The implication of this is that you now need to ensure that even those isolated
patches far from their neighbours should be included within the protected areas
network, since they are more likely to contain a unique suit of species
A Price on its Head
Increasingly conservationists are being drawn into the realm of economics and to
place value on natural assets, be it utility or aesthetic. This approach is leading
to the trade and bartering of natural remnants. So proposed development in a
sensitive environment will require that another similar area (similar species
composition or vegetation type) in some way is secured through financing and is
termed a biodiversity offset. While merit exists in this, at what point does the
commodity become so rare that you are forbidden to trade in it like rhinoceros
horns? Hopefully laws of demand and supply will inflate this valuation of natural
habitats for biodiversity offsets as they become rarer to a situation where they
cannot be traded when they get too rare. The biodiversity offset concept does
not recognize that vegetation types like West Coast Renosterveld and Sandplain
Fynbos remnants are virtually unique unless right next to one another. Will our
valuations prove to have been realistic or will biodiversity have got shortchanged?
Private ownership of land is a western concept alien to most of our ancestors,
and indigenous cultures expressly acknowledge that humans are meant to be
stewards of it and the plants and animals that are found on the land and in the
water. While the General Electric Corporation opened the doors to patenting
altered genes and therefore life itself, corporations like Monsanto have exploited
that niche by securing literally thousands of patents under the pretext that
because they mapped the DNA they own that life form, irrespective of whether
they modified it or not, or if it were a cultivar that has been nurtured by
generations of indigenous people. So it seems that biodiversity can also be
owned and even stolen, does ownership mean you can dispose of it at will? If
you were to own the Mona Lisa would society allow you to willingly destroy it?
Having established that evergreen forests, pandas, Mona Lisa and biodiversity
are owned, what is the responsibility attached to its ownership?
A Botanical Society’s report some ten years ago listed Milnerton Race Course
as the highest priority conservation site on the Cape Flats, yet it was sold for
development that will conserve two isolated patches of Sandplain Fynbos.
Kenilworth Race Course looks to have yet more development unless measures
are taken and funds secured to safeguard it. Some 50ha of Driftsands Nature
Reserve has been de-proclaimed to provide for development. The natural
habitat on my own campus was rated 8th most important, and yet we have
already seen a small part of its Sandplain Fynbos removed for a new building.
Sites like Century City exist today with only a fringe of Sandplain Fynbos around
the wetlands and Eskom brushcut yet another Sandplain Fynbos site. It seems a
chain reaction of events is unfolding similar to a century ago that lead to the
extinction of the Passenger Pigeon. Then a few greedy and hedonistic people
insisted that it was their personal freedom and pleasure to shoot the last few
birds (“last chance to shoot” hunting parties were organized to this end). Will our
excuse also be a mixture of profit and pleasure?
Biodiversity Stewardship
Landowners who wish to develop on the last remnants of Sandplain Fynbos or
Westcoast Renosterveld should realized their action are no different to eating
panda paws from a dinning room table crafted from rare Afromontane timber.
They are also depriving future generations of an experience. Further, by
conserving such sites, we have some idea of what existed before the European
colonists and global economies transformed them. The new EIA legislation
needs to be applied to ensure that our crown jewels are conserved not just
selective rare species that are the constituent mineral stones within the crown.
With the new legislation and South Africa’s commitment to mapping all of the
natural vegetation (currently there are a large number of fine-scale mapping
projects) more rigorous and defensible planning procedures will ensure that we
move away from piece-meal conservation efforts inherited from past legislation
like the USA has with its Endangered Species Act. This act ultimately
compromised biodiversity since it often lead to endangered species being
identified and destroyed prior to the environmental impact assessment, a
circumstance not unknown in South Africa.
Unfortunately most developers still hold onto the view that the presence of a few
rare or threatened species is of critical importance to conservation practice. This
paradigm has been overturned so the habitats that support the species are the
new currency for conservation. Nevertheless the divide between protected areas
and development needs to be the basis for synergy. Currently Protected Areas
are an offset to a landscape-wide trashing of the environment that will ultimately
lead to both losses of natural habitat and increasingly unsustainable urban life
styles. I do not believe that every remnant of vegetation needs to be fenced with
restricted access, while there may be merit in particular cases, natural vegetation
remnants could easily provide aesthetic but low maintenance landscaping , with
value being added if used for monitoring of the urban environment and for
education. Remnants of natural vegetation are part of our indigenous precolonial heritage, like burial sites and rock paintings and provide us and future
generations with glimpses of the past safeguarded from the homogenizing effects
of the dot.com global village. Those who fund developments need to be made
aware of social, cultural and environmental issues and where possible provide
their funds for development that embraces sensitive design and integration of
past and present elements be they artifacts of culture or designs of nature. Like
other resources such as petroleum, all land containing a rich tapestry of
biodiversity should be used as frugally as possible so that each may provide for
our children’s children’s welfare; otherwise the sands of time are indeed running
out for vegetation types like the Cape Flats Sandplain Fynbos.
Photos:
Milnerton Race Course – the most species rich site for Lowland Fynbos is
experiencing extensive and encircling housing development.
Century City – A Cape Flats Sandplain Fynbos, where 16ha of wetlands and its
fringes were left undeveloped to form a Nature Reserve, but remains poorly
integrated with the commercial hub.
Most of UWC campus’s Sandplain Fynbos fall outside the current proclaimed
nature reserve, but were originally included within it. Former protected Sandplain
Fynbos is now available for new buildings and one has already been erected but
its landscaping is poorly integrated with the natural vegetation.