species conservation strategies shorea lumutensis: genetic variation and conservation david boshier,...

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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

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