Species conservation strategies Talbotiella gentii genetic variation and

Species conservation strategies Talbotiella gentii: genetic variation and conservation David Boshier, Daniel Dompreh and Mike Swaine

MSD Bandai Hills Worobong Yongwa Sapawsu ME D SD Krobo SM WE Forest Reserves in Ghana and distribution of Talbotiella gentii Dompreh, 2008 100 km

Records of Talbotiella populations in Ghana Red dots = Extant populations, Yellow dots = Extinct populations.

Sapawsu

Yogaga Bandai

Yongwa

Talbotiella gentii 15 of 28 populations now extinct Most of those extinct are outside reserves Threats inside and outside reserves from fires, firewood cutting Populations range in size from 2 -500 adult trees

1982 1990 2005 Damage of Talbotiella population at Krobo mountain from fire and fuelwood exploitation over 23 years

Aburi Botanical Gardens

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 • effective population size (Ne) more critical than survey numbers (N) - may need 5, 000! • in trees Ne smaller than N due to: overlapping generations, dioecy, asynchronous flowering, fecundity differences between individuals

Where should we conserve? In situ Ex situ In situ - reserve system of undisturbed, protected areas within natural distribution (ecosystem based) Ex situ - artificial maintenance of populations outside natural distribution (species based)

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 sufficient

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

Conservation of biodiversity ex situ : methods and limitations • Useful, but resources limit application to few species (usually commercial) • Last possibility holding for highly endangered species • Complementary to other approaches

Bottleneck genetic drift

Table 3 Within population genetic variability in Talbotiella gentii, estimated by percentage of polymorphic loci for 83 RAPDs polymorphic bands (8 primers) Population Abiriwapong Botriansa Yongwa Nayom Doorkper Sapawsu Hospital Chalet Ajena Kuwere Krobo Yogoga Hotel Boobohene Oseikrom Senkyeso Kwame Addo Population size No. of samples % polymorphic loci >100 2 >100 39 21 >50 2 >50 16 >20 11 27 20 6 2 3 16 2 13 5 5 8 2 8 6 4 8 5 5 2 2 16. 3 2. 1 13. 6 5. 2 3. 9 8. 1 0. 8 8. 4 4. 8 3. 1 7. 7 7. 9 4. 4 2. 1

Figure 3. Effect of geographic distance of pollen source on initial fruit set in Talbotiella gentii

Talbotiella gentii each group summarize on wall chart paper or Power. Point Remember - need a conservation objective - prioritize actions – resources are limited list problems by type - genetic, which pops. too small? which are different? - other types of problems which conservation methods - in situ, ex situ, circa situm? who? will do, what? where? how will you pay for it?