Chapter10


1. Managing protected areas

Ecological Infomatics - Conservation Biology

Chapter 10: Managing Protected Areas

By Nicklaus Kruger


2. Managing protected areas1

Managing Protected Areas

The management of protected areas requires a thorough understanding of several ecological and evolutionary principles. Among these are:

Carrying capacity: The carrying capacity is a statistical estimate of the maximum possible population of a particular species that can exist in a particular ecosystem without significantly degrading the environment.

Minimum viable population size: A statistical estimate of the smallest possible size at which a population can exist in a particular environment without facing significant risk of extinction from natural disasters or demographic, environmental, or genetic stochasticity.

Ecosystem function: Management requires a general understanding of the dynamics of the environment in question, including abiotic and biotic factors. For example, adequate management requires knowledge of the temperature ranges and species found in the region.

Predator/prey dynamics: Predation is one of the best-studied biological interactions, and one of the foundational principles upon which ecology is based.

Competition: Competition is, like predation, one of the bedrock principles of ecology.

Some of these concepts will be explored in more detail a bit later.

Many other principles are involved in the management of protected areas. Of particular importance is the fact that environmental management not only has ecological aspects, but also social, economic and political ones.

References:

1. Born, S.M. and W.C. Sonzogni (1995) Integrated environmental management: Strengthening the conceptualization, Environmental Management 19(2):167-181


3. Some quick definitions

What is a Protected Area?

Before we can discuss the management of protected areas, we need to devote a little bit of time to figuring out what they are. In simplest terms, a protected area is an area of land (or ocean) whereon human activity and development is restricted and regulated, for the good of the environment. Of course, they are rarely entirely void of human interference.

The World Commission on Protected Areas (WCPA) was established in 1959. There are over 44 000 protected areas worldwide, amounting to almost 10% of the terrestrial surface.

There are several types of Protected Area. They are defined in legalistic and seemingly circular manner by the Acts of the country, and seemingly comprehensible only to lawyers and politicians, but it is worth drawing a (somewhat hazy) distinction between them anyway.

National Park:

In South Africa, there are 20 National Parks, 15 of which have overnight tourist facilities. These parks are: Kruger, Table Mountain, Marakele, Golden Gate, Vaalbos, Mountain Zebra, Addo Elephant, Tsitsikamma, Knysna, Wilderness, Bontebok, Agulhas, West Coast, Karoo, Namaqua, |Ai-|Ais/Richtersveld, Augrabies, Kgalagadi, Mapungubwe and Tankwa Karoo. Together, these parks total about 3 594 594 ha, or around 4% of the entire area of South Africa.

National Reserve:

National Reserves, like Parks, are protected by serious legislature.

Zoo:

Zoos (or zoological gardens) do not attempt to provide animals with a natural habitat. The aim of a zoo is to amuse human visitors with a wide sample of biodiversity, divorced from its original context. That's not to say that there's no merit in zoos - they stimulate public interest in wildlife, and provide a tangible link to organisms that may be endangered or threatened. Also, as zoos allocate far less space to individual organisms than protected areas, they are often the last resort for the preservation of species whose ranges have been greatly restricted by development (this is, of course, only a temporary solution, a stopgap measure before reintroduction).

Botanical Garden:

Botanical gardens, like zoos, are maintained for maximum visual impact, rather than attempting to mimic nature. They function similarly to zoos, and provide similar benefits.

References

2. IUCN (1969) Standards and nomenclature for protected areas. Resolution. 10th General Assembly of IUCN. New Delhi, India, November 

3. IUCN (1978) Categories, criteria, and objectives for protected areas. IUCN, Morges, Switzerland. 26 pp

African Parks Official Website

http://www.africanparks-conservation.com/index.html

South African National Parks Official Website

http://www.sanparks.org/

National Protected Areas Act No. 57 of 2003

http://www.sanparks.org/about/default.php

National Parks Act

http://www.sanparks.org/about/acts/NatParksAct.pdf

Goodwin, H. (2002) Local Community Involvement in Tourism Around National Parks: Opportunities and Constraints. Current Issues in Tourism 5(3&4): 338-360

Available online at: http://www.multilingual-matters.net/cit/005/0338/cit0050338.pdf


4. Carrying Capacity4

References

4. Sagoff, M. (1995)Carrying Capacity and Ecological Economics. Bioscience 45(9):610-620


5. Culling

Culling

Culling is simply defined as the controlled killing of a limited portion of a population of a particular animal species in a particular region. Culling is employed in many circumstances - breeding programs may employ it to improve breeding stock by eliminating the individuals with deleterious or undesirable characteristics; culling may be implemented in an attempt to limit the spread of disease through a region; or to prevent the population exceeding its carrying capacity and negatively impacting the abiotic environment and other species in the community. The last two reasons are particularly important for the management of protected areas and game reserves. The carrying capacity of a particular environment is the number of organisms of a species it can support for an extended period of time without the environment degrading significantly.

Carrying capacity is a particularly important factor with species that have a large effect on their environments, e.g. elephants. Culling is an important consideration in South Africa, especially in the Kruger National Park, which houses a very large population of elephants. Culling in the Park was banned in 1995, but since then the elephant population has boomed, and discussions resumed last year as to the viability of the implementation of a culling program (http://www.planetark.com/dailynewsstory.cfm/newsid/29953/story.htm/).

In the case of animals with slow recruitment rates, adults are often targeted by culling efforts. Again, elephants are a prime example. Their orphaned young, easily captured and transported, are then relocated. Without proper elephant socialization, young male elephants can become unruly and dangerous to other elephants, wildlife and humans.

Image Credits:

http://images.google.co.za/imgres?imgurl=http://library.thinkquest.org/

www.scidev.net

www.elephantvoices.org


6. Alternatives to Culling

Alternatives to Culling

The main argument in favour of culling is that it is cheap and easy to implement. On ranches, culling also can bring direct economic benefits (the sale of the flesh of the animals for meat, for instance, or the sale of elephant tusks for ivory, though this is frowned on, to say the least).

Several alternatives to outright culling have been suggested. Of these, the most prominent and plausible are the use of contraceptives, and the transport of surplus animals.

The use of animal contraceptives - thus cutting off reproduction rather than life - is one alternative to culling. This strategy is more humane, but also less practical. For one thing, this still leaves a very large population of animals in the area. For long-lived species such as elephants, this can see the environment degrading regardless of the fact that recruitment is slowed or stopped.

Transportation of excess animals to other protected areas - especially those that are far beneath their estimated carrying capacities for the particular species concerned - is another possibility. The problem with this is the money and effort expended in the capture and transport of the animals. For large animals (elephants, rhinos) this can be particularly high. Parks and reserves operate on limited budgets, and it's not always feasible to attempt this mode of action. Also, if a species is thriving in all the protected areas to which they would legitimately be sent, this becomes essentially a non-option.

References

5. Zhang, Z. (2000) Mathematical models of wildlife management by contraception. Ecological Modelling 132(1):105-113


7. Predator/Prey Cycles6

Predator/Prey Relations 

Organisms must ingest food to provide the energy to keep their internal environments out of thermodynamic equilibrium with their external environments. In other words, they need to eat to live. Many organisms are autotrophs - they derive chemical energy from nonliving sources. Plants, which use radiant energy and water from the sun to derive organic compounds from inorganic molecules, are an obvious example of this mode of feeding. Other organisms get their carbon from living organisms - animals, for example, eat plants or other animals. The species that is fed upon is the prey species; the feeder is the predator.   

Predation has received no less attention from ecologists than has competition. In its broadest sense - food consumption - predation is the prime mover of energy through the community, and defines the links in the food chain. Predation also is a basic factor in population ecology and evolution. Prey populations largely determine the growth rate of predator populations because they provide the food necessary for growth and reproduction. Conversely, predators tend to reduce the growth rate of populations of their prey. Whether predators can substantially reduce the equilibrium size of a prey population is, however, a controversial question. When predators selectively prey on individuals of different ages, they alter the age structure of the prey population and change its dynamics. 

We may ask many questions about predator-prey relationships. To what extent do predators stabilise, or cause cyclic fluctuations in, prey populations? Do predators limit prey populations below the carrying capacity of the environment for the prey? If predators are so efficient that they can substantially reduce prey populations, how do they keep from eating too many of their prey? Do predators act to maximise their returns, that is, do they "manage" prey populations? There is such a huge diversity of predator and prey species that any generalization of their attributes is not easy. However, the dynamics of predation have been a topic of study by ecologists for decades. Still, surprisingly little is known about predator and prey relations in nature, and much of what we know is a rather coarse mixture of field observations and anecdotes, and experiments with laboratory systems and using mathematical models of population processes.   

Regardless of any interactions predators nearly always limit the distribution of prey species to a narrower range than limited by physiological constraints. That is to say, predation narrows a prey species' niche. 

Thus when an efficient predator removes individuals it makes room for other species who have similar niches but are not eaten as much. There are many factors that influence relationships between predator and prey, including relative size, population growth rate, and many others. Predators tend to be larger than their prey (some pack hunters may prey on organisms larger than themselves - e.g. a pack of wolves bringing down a moose). The size difference may vary - we may think of cheetah and impala, where the prey is a little smaller than the predator, but some predators feed on huge quantities of minute prey such as Blue Whales and krill (mainly water dwelling species as not too many dense species in the air). As the ratio of prey to predator gets closer to one so the specialisation must increase to kill the prey. Eventually there is a limit beyond which the prey is too big. 

At the other end of the spectrum are the "live-in" predators, or parasites, where the survival of the predator depends on the survival of the host! This is analogous to herbivores, e.g. elephant and vegetation, while beetle larvae and seed predation is a little different.  

The cyclical dynamics of predator-prey systems are potentially unstable, as is seen in the lab or in protected areas where predators sometimes drive their prey extinct (and then either starve themselves or switch to a new prey species).

In nature, stability of predator/prey systems is promoted by a number of factors. Due to environmental heterogeneity, some prey are likely to persist in local "pockets" where they escape detection. When predators eradicate most of the prey in the environment and their numbers begin to decline due to starvation, the "pocket" prey can fuel a new round of population increase. Furthermore, prey evolve behaviors, armor, and other defenses that reduce their vulnerability to predators. Finally, predators may simply switch to alternate prey species if another prey species becomes rare, giving that prey species time to recover before the depravations continue. 


8. Predator/Prey Cycles: Lynx vs. Rabbits6

Predator/Prey Cycles: Lynx and Rabbits

The Canadian lynx, Lynx canadensis, feeds primarily on the snowshoe hare, Lepus americanus. Hare populations follow a 8-11 year boom-bust population cycle. Lynx populations follow shortly thereafter. This cycle is particularly well-known because hunting and trapping records go backseveral decades, and population numbers can be tracked by numbers of pelts sold over the years.

References:

6. Stenseth, N.C., W. Falck, O.N. Bjørnstad, and C.J. Krebs. 1997. Population regulation in snowshoe hare and Canadian lynx: Asymmetric food web configurations between hare and lynx. Proceedings of the National Academy of Sciences USA 94:5147-5152

Image Credit:

Cats! Wild to Mild: http://www.lam.mus.ca.us/cats/P12/


9. Fire Ecology7,8

Fire Ecology

Perhaps the best example of the dynamic equilibrium approach to conservation ecology comes from the use of fire regimes. Fire has an important role to play in many ecosystems, but this was a fact not recognized for many years. Fire ecology, the study of the impact of fires on ecosystems, only really became of interest once the equilibrium model of communities was replaced by the dynamic equilibrium view.

Some ecosystems have historical fire regimes that have shaped ecological communities over evolutionary time scales. Indeed, in some ecosystems fire is integral to ecosystem function and biodiversity, and the organisms in these communities are adapted to withstand or even depend on or exploit fire.

Fire suppression, the policy employed in environmental management for most of the history of the discipline, has resulted in significant changes to many fire-dependent ecosystems. In many cases, fire suppression has just lead to wildfires, when they do break out, being particularly severe, often damaging the particular ecosystem beyond hope of recovery (more time for more significant biomass to build up, increasing fire intensity).

References:

7. Bond, W.J., Keeley, J.E. 2005. Fire as global 'herbivore': the ecology and evolution of flammable ecosystems. Trends in Ecology and Evolution 20: 387-394

8. Bond, WJ, Woodward FI, Midgley GF. 2005. The global distribution of ecosystems in a world without fire. New Phytologist 165:525-538


10. Fire Regimes9

Fire Regimes

The restoration of natural fire regimes has become important in the management of many ecosystems. South Africa has led the way in terms of environmental management through the careful implementation and control of fire in protected areas. The fynbos biome, in particular, is highly fire-adapted, and much study has been done on the particular dynamics of fynbos fire regimes in South African National Parks.

Fuel Consumption and Fire Spread Pattern

In a natural (or near-natural) ecosystem, fire can burn at three levels.

Ground Fires: burn through soil that is rich in organic matter

Surface Fires: burn through surface litter

Crown Fires: burn through the tops of shrubs and trees

Of course, the three levels are not exclusive - ecosystems may have fire regimes consisting of any combination and concentration of crown, ground and surface fires.

Fire Intensity

Fire intensity is a measure of the amount of energy released during a fire. This is difficult to measure directly, but can be estimated by flame length and rate of spread. More direct methods include the use of empty water-filled tin cans as makeshift calorimeters, though the readings can only be taken after the fire has passed.

Fire Severity

Fire severity refers to the impact that a fire has on an ecosystem. While clearly related to the concept of fire intensity, they are rather distinct concepts. There are many ways to define fire intensity - through an estimate of plant mortality, or recovery time after the disturbance, for example. Fire severity is thus highly dependent on the composition of the particular communities involved (an intense fire may demolish a particular community while leaving a different community, better-adapted to intense fire regimes, largely unaffected).

Fire Frequency

Fire frequency indicates the commonality of fires in a particular ecosystem. There are two main ways of defining fire frequency - either as the interval between fires at a given site, or as the amount of time it takes to burn the equivalent of a specified area.

Fire Seasonality

Fire seasonality deals with the time of year during which fires are most common. Fires often occur during the dry season (regions are often defined as being either summer-rainfall or winter-rainfall). Summer-rainfall regions tend to be harder-hit by fires than winter-rainfall regions (higher temperatures). Fire seasonality may also coincide with the time of peak lightning occurrence.

References

Bond, W. J., and J. E. Keeley. 2005. Fire as a global 'herbivore': the ecology and evolution of flammable ecosystems. Trends in Ecology & Evolution 20: 387-394.


11. Fire Ecology and Management

Fire Ecology and Management

In fire-dependent ecosystems, the dynamic ecological approach to management has been to attempt to mimic the natural fire regime. This entails extensive study of the pre-modern history of fire events in the ecosystem, including long-term fire use by hominids. South Africa has led the way in its management approach to fire regimes, particularly in the Kruger national Park, which has a long and detailed records of fire events and a carefully regulated fire policy.

Image Credit:


12. Fire and Fynbos10

Fire and Fynbos

The fynbos biome is incredibly bio-diverse, and its composite species tend to be highly fire-adapted. Fynbos ecosystems are highly fire-dependent - many seeds germinate only after fires. Proteas become senescent when they go without burning for forty or so years, and die without recruitment (which requires the heat of fires), leading to local extinction (more on that later).

Some Fynbos Fire Adaptations

Serotiny: Seeds are stored in hardy fire-proof cones, to be released when the parent dies.

Myrmecochory: The seeds are transported by ants into underground (and thus fire-proof) nests - the ants consume the elysium, the outer coating of the seed. Seed germination occurs according to temperature cues, when a fire burns the surface vegetation.

Fynbos Fire Regimes

Fire spread patterns vary, but trees are not widespread, and so crown fires tend to be less frequent.

Fire intensity: Fynbos is low in biomass, so fire intensiteis tend to be fairly low

Fire severity: Severe burning usually occurs naturally on a 10-15 year cycle.

Fire frequency: Natural fires are fairly frequent in fynbos regions, but severe burnings are thought to occur naturally approximately once every ten to fifteen years.

Fire seasonality: Fynbos fires occur mostly during the dry summer months.

Managing Fire and Fynbos

Managing fires in fynbos is more than a case of just ensuring that the area gets burnt once in a while. As with all ecosystems, the factors contributing to ecosystem function are many and complex. In this case, there are many things that affect the fynbos fire regime. And the fire regime is not the only aspect that needs to be managed to keep the system functioning.

Invasive alien species:

Invasive aliens are a major problem in South Africa. In addition to the general problems they create, they may also interfere with the fire regime of the indigenous fynbos. Some invasive aliens are able to survive fires - Pinus (the European pine) for example. Pine trees have thick bark, and thus are able to survive less intense fires. When they do burn, the added biomass increases the fire intensity, and fynbos fire adaptations are not normally sufficient to withstand this. Thus the removal of Pinus from a fynbos region needs to be carefully controlled.

References

10. Archibald S, Bond W.J, Stock WD, Fairbanks DHK (2005) Shaping the landscape: Fire-grazer interactions in an African savanna. Ecological Applications 15: 96-109.

Image Credit:

http://www.humanflowerproject.com

http://flickr.com/photos/leita/page7/

http://www.firegroundaction.com


13. Local Extinctions and Reintroductions 11,12

Reintroducing Locally Extinct Species

Extinction - the end of a species or other taxon - is a fact of life. Over the course of the history of life on Earth, around 99% of all species that have arisen have gone extinct. But species do not, as a general rule, go extinct throughout the entirety of their range all at once.

Local extinction is the extinction of a population of a species in a certain area - the end of a species within a portion of its geographic range. Because members of the species still exist in other locations, it is theoretically possible for these local extinctions to be reversed by the recolonization of the area by conspecifics, or their reintroduction.

References

10. P. A. Rees. 2001 Is there a legal obligation to reintroduce animal species into their former habitats? 35(3):216-233

11. S.M Cheyne. 2006. Wildlife reintroduction: considerations of habitat quality at the release site. BMC Ecology 6:5-9


14. Local Extinction (cont)11,12

Local Extinction (cont)

Local extinction is often a precursor to full taxon extinction, however, and this is almost always the case with the majority of extinctions. Mass extinction events may prove to be exceptions, but even in this case, extinction is likely to occur at different times within the species range.

For reintroduction to be successful, the original causes of the local extinction must be addressed. Thus, if the species went extinct because of the introduction of a certain predator into a region, the removal of the predator might be necessary before reintroduction becomes viable.The exact causes of local extinctions are hardly ever simply obvious, and very rarely easily fixed.

In addition, the ethics of reintroducing extinct species is another matter to consider. If deers go extinct in a region because of heavy predation by wolves, are we meant to reintroduce them? Or is that interfering too much with the natural order? These are the sort of questions that must be addressed before attempting the reintroduction of a species that has gone locally extinct.

(Anagenesis, or branching evolution - the diversification of a species into several species, and the formation of higher taxa by further diversification - depends on the accumulation of differences between populations of a particular species. Thus the local extinction of a species is almost certain to mean the end of a possible evolutionary lineage. Of course, there is, unfortunately, no practical way to deal with this largely philosophical issue.)

References

http://www.bagheera.com/inthewild/ext_background.htm

Image Credit:


15. Reintroducing wolves to Yellowstone Park

Some good online resources to consult about the reintroduction of wolves to Yellowstone:

Yellowstone Outdoor Adventures: http://www.yellowstone-bearman.com/wolves.html

A very thorough description of the reintroduction of the wolves.

The Official Website of Yellowstone Park: http://www.nps.gov/yell/nature/animals/wolf/wolfrest.html

An even more detailed look at the actual process of reintroduction of the gray wolves.

Image credits:

http://no.wikipedia.org/wiki/Liste_over_kjente_ulvearter_og_underarter

http://www.jacksonholenet.com

http://www.windowsintowonderland.org


16. Local community involvement13

References

12. McNeely, J.A. (1993) Diverse nature, diverse cultures. People and the Planet 2(3): 11-13.


17. The San and the Kruger National Park

Image Credits:

www.wildland.com

www.fredskorpset.no/

http://www.suedafrika.net/NORDGIFS/knp_metsi.jpg


18. Biophilia14,15

Biophilia

Biophilia is a term coined and formalized by the Harvard biologist E.O. Wilson, to denote the deep effect of evolution on the human mind. The basic idea is simple, and is linked to the discipline of sociobiology - or, more latterly, evolutionary psychology. Most of human evolution occurred on the African savannahs. Thus, our minds have been shaped by selective pressures from that environment.

Biophilia (and its cousin, biophobia) refers to the likes and dislikes these selective pressures inflicted on us. Studies of human reactions to landscape paintings, for example, suggest that we respond most favourably to those aspects of paintings that evoke aspects of life as a plains ape.

The most common phobias are things that might have been dangerous to us on the African plains, but are hardly likely threats to our safety in our modern lifestyles. Snakes and spiders are hardly as likely to do us harm as guns or automobiles - both immense killers of human beings - and yet guns and cars are not feared in anywhere near the same manner.

Biophilia may be a recent addition to science, but as a concept, it's been implicit in our folk understanding for ages. It's implicit in the advice to go off into the countryside to cheer up when you're feeling down. It underlies the very notion of the tourist industry - that people enjoy the presence of nature enough to pay for it.

For conservation efforts to succeed, biodiversity needs to be important to people. Beyond the direct economic benefits of the existence of ecosystems (estimated at $33 trillion worth in humanity-sustaining stuff), there is also biophilia to consider - we actually like natural landscapes, and we'll pay to preserve them so we can keep on liking them...

References

Griffin, D.R. 1985. Biophilia. The Quarterly Review of Biology 60(4):482-483

Orr, D.W. (1992) The love of life. Conservation Biology 6(4):486-487

Image Credits:

http://www.exploretravel.com

http://www.animalinyou.com

http://www.timart.be


19. Environmental management - some general notes

Environmental management: Some general notes

Ecosystems develop naturally on an evolutionary timescale - as species evolve and go extinct, immigrate and emigrate, and as abiotic factors fluctuate, communities evolve.

These timescales are, for the most part, far longer than an individual human lifespan. This, combined with the fact that ecology is a young science (natural history, or observation of nature, is far older, but the term ecology was coined in the nineteenth century, and it has only recently become rigorously empirical), brings into question our ability to determine how we should guide ecosystem development.

In practice, the task of developing a means of predicting the likely course of ecosystem evolution, and guiding it, is far beyond our capabilities at the moment. Instead, environmental management has focused on preserving, as far as is possible, what we think to be the natural status quo of an ecosystem over the very recent past.

This can lead to an equilibrium view of ecology, where we attempt to "preserve the harmony of nature". But more recently, the dynamic view of ecology has permitted us to factor into account short-term disturbances and alterations to ecosystems. And, while conservation biology focuses on keeping things the same (that is, keeping local biodiversity within a certain range) and this is in opposition to the idea that in nature, all is in flux, the short timescales involved in human interference in ecosystem function mean that there really isn't any other strategy that we can adopt.


20. References

Born, S.M. and W.C. Sonzogni (1995) Integrated environmental management: Strengthening the conceptualization, Environmental Management 19(2):167-181

IUCN (1969) Standards and nomenclature for protected areas. Resolution. 10th General Assembly of IUCN. New Delhi, India, November 

IUCN (1978) Categories, criteria, and objectives for protected areas. IUCN, Morges, Switzerland. 26 pp

Sagoff, M. (1995)Carrying Capacity and Ecological Economics. Bioscience 45(9):610-620

Zhang, Z. (2000) Mathematical models of wildlife management by contraception. Ecological Modelling 132(1):105-113

Stenseth, N.C., W. Falck, O.N. Bjørnstad, and C.J. Krebs (1997) Population regulation in snowshoe hare and Canadian lynx: Asymmetric food web configurations between hare and lynx. Proceedings of the National Academy of Sciences USA 94:5147-5152

Bond, W.J., Keeley, J.E. (2005) Fire as global 'herbivore': the ecology and evolution of flammable ecosystems. Trends in Ecology and Evolution 20: 387-394

Bond, WJ, Woodward FI, Midgley GF. (2005) The global distribution of ecosystems in a world without fire. New Phytologist 165:525-538

Bond, W. J., and J. E. Keeley (2005) Fire as a global 'herbivore': the ecology and evolution of flammable ecosystems. Trends in Ecology & Evolution 20: 387-394.

Archibald S, Bond W.J, Stock WD, Fairbanks DHK (2005) Shaping the landscape: Fire-grazer interactions in an African savanna. Ecological Applications 15: 96-109.

P. A. Rees (2001) Is there a legal obligation to reintroduce animal species into their former habitats? 35(3):216-233

S.M Cheyne (2006) Wildlife reintroduction: considerations of habitat quality at the release site. BMC Ecology 6:5-9

McNeely, J.A. (1993) Diverse nature, diverse cultures. People and the Planet 2(3): 11-13.

Griffin, D.R. 1985. Biophilia. The Quarterly Review of Biology 60(4):482-483

Orr, D.W. (1992) The love of life. Conservation Biology 6(4):486-487