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Species conservation strategies
Shorea lumutensis: genetic variation and conservation
David Boshier, and SL Lee
Small hermaphrodite flowers © SL Lee
Sub-sessile fruits with three outer and two inner wings
© SL Lee
Balau Putih – White Balau
© SL Lee
Shorea lumutensis
© SL Lee
Shorea lumutensis is restricted to Manjung District, Peninsular Malaysia, and confined to five forest reserves. Endangered as distribution restricted & habitat potentially threatened by human activities.
Endemic to Peninsular Malaysia
© SL Lee
Dry coastal hill dipterocarp forests on moderate-fertility soils, in microclimates where
drainage is good or where high soil moisture levels cannot be
permanently maintained
The number of large trees was estimated to be < 500 for these five populations
Threat – logging activities
(Segari Melintang FR)
© SL Lee
© SL Lee
Threat – excavation of stone (quarry) & conversion to oil palm plantation (Teluk
Muroh FR)
Threat – Land development for tourism (Pangkor Selatan & Sg. Pinang FRs)
Threat – Land development for tourism (Pangkor Selatan & Sg. Pinang FRs)
© SL Lee
Need for research
• Little was known about the biology of S. lumutensis
• Research aimed to assess the population ecology and population genetics to elucidate specific ecological and genetic requirements for the species’ existence …
• … In order to subsequently develop conservation strategies
Population survey
Demographic structure
Population dynamics
Flowering biology
Germination & seedling studies
© SL Lee
• Total of 416 individuals >1 cm dbh recorded within 8ha plot
0
40
80
120
160
200
0 40 80 120 160 200 240 280 320 360 400
(m)
• Density of S. lumutensis >30 cm dbh within plot, 4.4 trees/ha
© SL Lee
Large number of seedlings scattered around the mature tree
Large number of seedlings scattered around the mature tree
Short-term population dynamics (2001-2004)
• 75 trees died over the 3-year study period• Mortality was detected only at the two lowest-sized classes• Growth was slow - 0.3mm/yr to 2.4 mm/yr
Seedling performance
Two-year old
© SL LeeOne-year old
© SL Lee
Conservation alternatives
• Preservation of actual diversity
• Conservation of evolutionary potential
• Mantain options for future generations, while satisfying present needs
How big is “big enough”?
• 50/500 rule (Franklin 1980)• 50 - inbreeding depression to acceptable level• 500 - sufficient for new variation from mutation to
replace that lost by genetic drift
• refers to effective population size (Ne) rather than survey numbers (N) – so may need many more!
• in trees Ne smaller than N due to: overlapping generations, dioecy, asynchronous flowering, fecundity differences between individuals
Where should we conserve?
In situ - reserve system of undisturbed, protected areas within natural distribution (ecosystem based)
Ex situ - artificial maintenance of populations outside natural distribution (species based)
In situ - Ex situ
15
Conservation of biodiversity in situ : trees as a paradigm
Ideal reserve model
Emphasis: large, continuous, protected areas
Limitations: location, size, security, biology:– Movement of animals– Extensive distribution of many species– Gene flow between populations– Upland, non agricultural areas
Essential but not sufficient16
Conservation of biodiversity ex situ : methods and limitations seed banks - problems of regeneration
plantations - changes in gene frequencies, few populations
botanical gardens - deficiencies for gene pool conservation
17© RBG Kew © RBG Kew
- useful, but resources limit application to few species (usually commercial)
- last gasp holding for highly endangered species
- complementary to other approaches
Conservation of biodiversity ex situ : methods and limitations
Conservation of alleles
• common - rare what proportion?• widespread - localised what scale?
widespread localised common easy key rare (<0.05) sample size luck
Widespread vs locally common alleles
frequency Pop 1 2 3 4
Allele a 0.500 0.320 0.450 0.550
b 0.250 0.030 0.050 0.050
c 0.230 0.400 0.450 0.350
d 0.020 0.250 0.050 0.050
Table 3. Geographic distance (in km) for the five S. lumutensis populations.
Figure 2: Dendrogram of genetic similarities between the five populations of Shorealumutensis (bootstrap % values on branches based on 1000 replications).
How many conservation areas are required?
High levels of genetic
diversityLow population
differentiation
Exists in five populations
<500 large trees
• Selection of in situ gene conservation areas• How many conservation areas are required?
• How large does each conservation area need to be?
• How should conservation areas be designed?
• Monitoring?
• Management?
Conservation strategies: in situ conservation?
Conservation strategies: ex situ conservation?
• How?
• Where?
• Who?
Shorea lumutensis each group summarize on wall chart paper or PowerPoint
Remember need a conservation objectiveprioritise actions – resources are limited
list the localised but common alleles?list problems by type
- genetic, which pops. too small? which are different?- other types of problems
which conservation methods - in situ, ex situ?who? will do, what? where?how will you pay for it?
Ghazali Jaafar, Yahya Marhani, Mariam Din and Sharifah Talib for field and technical assistance.
The late Baya Busu, Ramli Punyoh, Mustapa Data, Ayau Kanir, Apok Kassim and Angan Atan for field assistance
Pn. Hamidah Mamat (FRIM) helped draw the maps.
© SL Lee © SL Lee © SL Lee
© SL Lee © SL Lee
© SL Lee