Opha Pauline Dube and M'B'M' Sekhwela

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Likely impacts of climate change on availability
of natural resources The case of Phane
caterpillar - Limpopo basin part of Botswana.

• Opha Pauline Dube and M.B.M. Sekhwela
• AF42
• University of Botswana

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Phane caterpillar Imbrasia belina of the
Emperor moth group
Veld Products non-agricultural timber
non-timber products used for medicinal
purposes, food, source of income
Devils Claw grapple plant
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The Host plant of Phane caterpillar is
Colophospermum mopane tree
Distribution of mopane vegetation
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Mopane vegetation over parts of Limpopo
basin-Botswana
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Phane Caterpillar

• Important food product
• A source of income for rural low income urban
  population
• There is active Phane trade between Botswana and
  South Africa
• Phane is currently freely available mainly on
  communal lands
• Phane -important fall back over periods of crop
  failure
• Cattle and birds also feed on Phane
• Most of the mopane vegetation in Botswana falls
  within the Limpopo basin

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Phane Can Be Competitive as a Source of Income
Are conditions of trade suitable Who benefits
most?
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Socio-economic Harvesting process is tough! But
who gains?
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AF42 linked with an ongoing GEF/SGP Phane
caterpillar and mopane woodland community study
(by Sekhwela, Ditlhogo, Ntseane and Dube)

• And has built upon a past EU/Uni. Bots woody
  biomass study (by Sekhwela)
• To bring in the issue of likely impacts of
  climate change on Phane caterpillar and
  implications on livelihoods

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Larvae bury 5 15 cm Depth to pupate under shade
The moth prefers to lay eggs on big trees
What factors influence each stage what
controls the timing of the emergence of each
generation?
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Potential Life Cycle Influential Factors
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Rainfall one significant factor
There is need for enough rainfall to percolate up
to 15 cm depth at which pupate are buried -for
the emergence of the moth Exactly how much is
needed?
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Amount timing of rainfall is important

• Delayed re-leafing of mophane trees means no food
  for the hatched larvae.
• More so for 2nd generation - Trees have to
  recover from defoliation from 1st generation

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Rainfall is important at each growth stage But
what are the thresholds?
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Temperature

• Dry hot environment The larvae hatch but may not
  emerge from the eggs.
• What is the threshold temperature for the eggs to
  hatch?

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Example I.belina egg larvae mortality trends
(Source Ditlhogo, 1996)
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• Environmental and climatic conditions
• life stage triggers?
• How do/will they influence growth or act as
  stage triggers ?

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Francistown A2 Scenario
Will these changes in rainfall have a
significant impact on reproduction of
Phane? How will the host plant be affected
what are the implications on Phane?
Francistown B2 Scenario
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Potential Life Cycle Influential Factors
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Harvesting Too early, too late
or Over-harvesting influence Phane regeneration
Sun dried Phane is of great economic value
(Source Ditlhogo, 1996)
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Fodder for Livestock
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• The host Mopane is also an important Woody
  biomass energy source and other wood needs for
  rural populations

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Recovery of woody plants from disturbances
Serule site
Average Coppice height after 1 year
Canopy Area

From initial CC Assessment in Southern Africa
Woody plants are likely to be favored Is mopane
one of the spps likely to thrive under future
CC? Is so in what form
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Spatial distribution of Mopane
NDVI ETM 11-02 Mosetse
ETM - Mosetse11-02
Classification
Defoliation by Phane caterpillar
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Veld Fires are driven by rainfall human
activity
Fire affects the host the papue buried
nderground
2002
Frequent fires How far does/will fire influence
Phane reproduction ?
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• Phane habitat extends to other non-mopane
• shrub/tree spps
• The larvae prefers to bury itself under moist
  shaded areas
• With mopane leaves defoliated shade is from
  non-mopane
• trees

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AF42
We only just began to look!
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