BCB341_Chapter9_reserve_design

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Transcript BCB341_Chapter9_reserve_design

FACULTY OF NATURAL SCIENCES
Reserve Design and Selecting
Areas to Protect
Rich Knight,
Biodiversity & Conservation Biology
UWC
knight.rich[at]gmail.com
1
Nature reserves 1

Nature reserves around the world need to contain most of
the worlds biota

The area of land to conserve is picked for a number of
reasons


Diversity

Rarity

Naturalness
They can also serve a number of other
functions

Hunting

Hiking

Money making
Ways of selecting reserves - size

The actual size of the piece of land that is being protected
is very important

E.g. – Mammal extinctions 3

Large reserves allow the re-colonisation from other parts of
the reserve 2

Large reserves support a fuller diversity and interactions 4

Many species have a minimum area requirement but not
often is there a maximum area requirement 5

Reserves must be worthwhile not just large pieces of
unwanted land 7
Ways of selecting reserves –
size 8

An argument for large reserves is
seen on Borro Colorado Island,
Panama

Made reserve in 1923

Contains birds that will not fly
over water

Spotted antbird (Hylophalx
naeviodes)

Bicolored antbird
(Gymnopithys bicolor)

Ocellated antbird
(Phaenostictus mcleannani)
Ways of selecting reserves –
size 9

Amazon Rainforest

Large problem in guarding the
reserves

Answer may be to place whole
watersheds in a single reserve

This would limit the access to the
reserve

It would also conserve all of the
aquatic resources in one water
system
Ways of selecting reserves size

Other studies have suggested that
many small reserves would be of
better conservation value

Simberloff and Abele (1976) 10

Studied red mangrove islands

Split islands into smaller
archipelago

Resulting islands had more
species
Ways of selecting reserves - size

Erwin et al. (1995) 11

Studied water birds on islands in the Florida Keys

Birds did better on the medium size of the smaller
islands

Seen in the White Heron
Ways of selecting reserves –
size 12

Two smaller reserves may be more beneficial for
genetic conservation

These two reserves must have occasional
migrations between the two populations

Sustains alleles and heterozygotes for a longer
period
Ways of selecting reserves –
size 13

In practice it is not always possible to have the reserve size
that is necessary

In Eastern North America the requirement for terrestrial
mammals is 5037 km2

In practice of the 2355 reserves

14 are greater the 2700 km2

8 are greater than 5037 km2

3 are greater than 13,296 km2
Ways of selecting reserves shape

Each reserve will have an edge that
abuts to the degraded matrix 14

The park perimeter to area ratio needs
to be checked

Smaller reserves will have more edge 2

Irregularly shaped reserves will
promote edge species but will cause a
decline in number of interior species 1

Heavily used roads can act as another
edge 15
Ways of selecting reserves – help
from computers 1

Reserve planners need to compromise between a number
of different factors

Computer programs can help to make informed decisions

Quantitative decision approach:

Indexing – potential reserves are scored against defined
criteria

Iterative techniques – used to assemble combinations
of reserves

Integer planning – often only use one criteria at a time
Ways of selecting reserves – help
from computers 1

For example – Multiobjective planning (MOP) and Simple
multiattribute rating technique (SMART)

Used in Nova Scotia, Canada

Five forest nature reserves are needed to complement the
two existing national parks

The suggested reserves were evaluated on:

Connectedness – inverse of distance between reserves

Maximise the total area of the reserve system

Maximise the number of rare plant species
Ways of selecting reserves –
Hot Spots

A biodiversity hotspot is an
area of land where there is
increased species richness,
high numbers of endemic
species and high numbers
of rare species 18

It is a way of creating priorities
for conservation

25 hotspots suggested by Myers et al. (2000) now increased to 34
19 20

These hotspots contain at least 0.5%of the world plant species as
endemics 19

Initiative being supported by conservation international 21

One of these hotspots is the cape floristic region
Ways of selecting reserves –
Umbrella species

No single taxon will be completely effective as a reserve selection
indicator

It is estimated that to conserve a viable elephant population for
1000 years it would take 1000 miles2 of land 16

Conserving this piece of land may protect other species

This may not always be the ideal land for conserving large
numbers of endangered species if it is the elephants alone that
are being concentrated on

Plants are probably the better umbrella taxon as they need more
area e.g. 17

In San Diego canyons

To preserve all of the bird species 2 canyons are needed

To preserve all of the plant species 10 canyons are needed
Ways of selecting reserves
–
Hot Spots 22

Cape floristic region – area of 87,892 km2

70% of the 9000 plant species present are endemic

Also important for birds, mammals and other
vertebrates

In the area 10.1% is already reserves but this is mainly
in the upland areas

The report by Cowling et al. (2003) suggested that
another 40,000 km2 be protected in some way

This is trying to take into account representativeness
and persistence

They warn that there will probably not be enough
money to carry out the full plan and that more
biodiversity will be lost as the plan is being
implemented
Ways of selecting reserves –
Hot Spots

One of the problems in using these hotspots
of biodiversity is that hotspots for different
species rarely overlap 23

There is probably a low correlation between
high species richness and high endemicity 18

Conserving hotspots may miss a species
vital to conservation 24
Wildlife Corridors

Wildlife corridors have been talked about in
the fragmentation lecture, chapter 2

They should link two fragments of
habitat that are being conserved

This is meant to allow for local
extinctions and re-colonisation

They should also allow for the gene flow that
was discussed when trying to keep genetic
diversity
Wildlife Corridors –
working

Fahrig and Merriam
(1985) – populations of
the white footed mouse
25

Aars and Ims (1999) –
populations of voles 26
Wildlife Corridors – not working

Review by Mann and Plummer (1993)

Problems

Fire

Disease

Introduced species

cost
Conclusions

It is agreed that biodiversity must be
conserved

The problem comes when decisions have to
be made on what to conserve

Reserve design is part of this problem as
different reserve designs will meet the needs
of different conservation goals
References
1.
Rothley, K. D. (1999). Designing bioreserve networks to satisfy multiple, conflicting demands.
Ecological Applications 9: 741-750.)
2.
Higgs, A. (1981) Island biogeography theory and nature reserve design. Journal of Biogeography
8: 117-124
3.
Newmark, W. D. (1995) Extinction of mammal populations in Western North American National
Parks Conservation Biology 9: 512-526
4.
Schwartz, M. (1999) Choosing the appropriate scale of reserves for conservation Annual Review of
Ecology and Systematics 30: 83-108
5.
Diamond, J. M. (1976) Island Biogeography and conservation: Strategy and limitations. Science
193: 1027-1029
6.
Terborgh, J. (1976) Island Biogeography and Conservation: Strategy and Limitations Science 193:
1027-1029
7.
Terborgh, J. (1974) Preservation of natural diversity: The problem of extinction prone species.
Bioscience 24:715-722
8.
Willis, E. (1974) Populations and local extinctions of birds on Borro Colorado Island, Panama.
Ecological Monographs 44: 153-169
9.
Peres, C. A. and Terborgh, J. W. (1995). Amazonian Nature Reserves: An analysis of the
defensibility status of existing conservation units and design criteria for the future. Conservation
Biology 9: 34-46
10. Simberloff, D. and Abele, L. (1976) Island Biogeography theory and conservation practice. Science
191: 285-286
References
11. Erwin et al. (1995) The value and vulnerability of small estuarine islands for conserving
metapopulations of breeding water birds. Biological Conservation 71: 187-191
12. Boecklen, W. (1986) Optimal design of nature reserves: Consequences of genetic drift. Biological
Conservation 38: 323-338
13. Gurd, D. B. Nudds, T. D. and Rivard, D. H. (2000) Conservation of mammals in Eastern North
American wildlife reserves: how small is too small? Conservation Biology 15: 1355-1363
14. Buechner, M. (1987) Conservation in insular parks: simulation models of factors affecting the
movement of animals across park boundaries. Biological Conservation 41: 57-76
15. Schonewald-Cox, C. (1988) Boundaries in the protection of nature reserves: translating
multidisciplinary knowledge into practical conservation. Bioscience 38: 480-486
16. Armbruster, P. and Lande, R. (1993) A population viability analysis for African Elephants
(Loxodonta africana): How big should reserve be? Conservation Biology 7: 602-610
17. Ryti, R. T. (1992) Effect of the focal taxon on the selection of nature reserves. Ecological
Applications 2: 404-410
18. Ceballos, G. et al. (1998). Assessing conservation priorities in mega diverse Mexico: Mammalian
diversity, endemicity and endangerment. Ecological Applications 8: 8-17
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20. Jepson, P. and Canney, S. (2001) Biodiversity hotspots: Hot for what? Global Ecology and
Biogeography 10: 225-227
References
21. Dalton, R. (2000) Ecologists back blueprint to save biodiversity hotspots. Nature 406: 926
22. Cowling et al. (2003) A conservation plan for a global biodiversity hotspot – the Cape Floristic
Region, South Africa. Biological Conservation 112: 191-216
23. Dobson et al (1997). Geographic distribution of endangered species in the United States. Science
275: 550-553
24. Reyers, B. et al. (2000) Complementartiy as a biodiversity indicator strategy. Proceedings:
Biological Sciences 267: 505-513
25. Fahrig and Merriam (1985) Habitat patch connectivity and population survival. Ecology 66: 17621768
26. Aars and Ims (1999) The effect of habitat corridors on rates of transfer and interbreeding between
vole demes. Ecology 80: 1648- 1655
27. Mann and Plummer (1993) The high cost of biodiversity. Science 260: 1868- 1871