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Society for Conservation Biology 16th Annual Meeting July 14-July 19 2002
co-hosted by DICE and the British Ecological Society
Abstracts for Conservation Genetics
Session Three
Wednesday 17th
July, 10.15 - 12.15, Rutherford Lecture Theatre 1
Chair: Mike Bruford
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timetable
(BLOCK CAPITALS indicate the presenting author)
10.15 - 10.30
BARCLAY, SHAUN D. and William B. Sherwin. School of Biological, Environmental
and Earth Sciences, University of New South Wales, Sydney, NSW, 2052, Australia.
<shaun.barclay@unsw.edu.au>
GENETIC MANAGEMENT OF ENDANGERED SPECIES: DOES IT WORK?
As more and more species face extinction through human-induced causes, conservation
programs are using captive management to provide stock for reintroduction, but the
genetic success of these programs is rarely monitored. We are conducting experiments
based on the captive breeding and successful reintroduction of the Greater stick-nest
rat (Leporillus conditor), an endangered native rodent of Australia. By taking
advantage of an extensive tissue collection and documentation of breeding and reintroductions,
this study provides a rare opportunity to check on genetic changes during sampling,
captivity, reintroduction, and establishment and maintenance of new populations.
Using nuclear and mitochondrial markers we show that the reintroduced populations
have lost genetic variation compared to source populations, including some populations
which appear to lack representation from one source, despite the presence of source
animals in the reintroduction. Although gene diversity has been reduced relative
to source populations, we show gene diversity in reintroduced populations is higher
than predicted by empirical models. This has implications in the management of all
endangered species, suggesting that reduction in genetic variation may not be as
severe as expected.
10.30 - 10.45
CIOFI, CLAUDIO, Gisella Caccone, Luciano Beheregaray and Jeffrey R. Powell. Department
of Ecology and Evolutionary Biology, Yale University, New Haven, CT 06520, USA <claudio.ciofi@yale.edu>.
CONSERVATION GENETICS AND POPULATION MANAGEMENT OF ISLAND ENDEMICS: GIANT TORTOISES
AND KOMODO DRAGONS AS A CASE STUDY
The degree of genetic differentiation found within island systems is important for
reconstructing phylogeographic histories and to clarify features of the population
ecology of species that have evolved during pre- and post-colonization events. The
known genetic structure of island endemics can also help in the formulation of short
and long-term management plans, particularly when integrated with ecological, demographic
and geographical information. This is relevant to island populations of endangered
giant reptiles, subject to a plethora of direct and indirect threats associated with
human occupation. Examples are provided here from the Galápagos giant tortoise,
a species that has endured heavy exploitation during the last three centuries. We
present data based on nuclear and mitochondrial DNA analyses, which elucidate the
evolutionary history of island populations and identify distinct genetic units, providing
data likely to impact conservation policies focused on reintroduction or augmentation
plans. A second case study concerns the integration of population genetics and ecology
for the management of extant populations of the Komodo dragon, an endangered giant
species of monitor lizard endemic to five islands in southeast Indonesia.
10.45 - 11.00
Evans, Ben J, Jatna Supriatna, Noviar Andayani, Mohammed Iqbal Setiadi, David
C. Cannatella, and DON J. MELNICK, Center for Environmental Research and Conservation,
1200 Amsterdam Avenue, Columbia University, NY 10027, USA, <BJE5@COLUMBIA.EDU>
(BJE, DJM). Section of Integrative Biology, Patterson Laboratories, University of
Texas, Austin, TX 78712, USA (BJE, DCC) Center for Biodiversity and Conservation
Studies, FMIPA, University of Indonesia, Depok, Java 16424, Indonesia (NA, MIS, JS).
MONKEYS AND TOADS DEFINE AREAS OF GENETIC ENDEMISM ON THE ISLAND OF SULAWESI
Preventing rapid biodiversity loss requires efficient allocation of conservation
efforts1 within hotspots - those areas where concentrations of endemic species clash
with unusually high levels of human activity2. One hotspot, Wallacea, encompasses
Sulawesi, the Lesser Sunda Islands, and the Moluccas. Sulawesi itself is too large
to protect, so designating conservation areas requires our understanding of patterns
of endemism within it. Superficially, these would seem to be idiosyncratic with,
for example, seven allopatric species of macaques (Macaca) geographically
overlapping one widespread species of toad, Bufo celebensis. Here we refute
this hypothesis, using genetic methods to show that the geographic locations of intraspecific
toad clades correspond almost exactly to the ranges of monkey species. These congruent
biogeographical patterns define seven separate areas of genetic endemism that are
likely shared by other Sulawesi endemics. Further protective measures are necessary
in these areas to conserve the highly partitioned and unique biodiversity on this
island. Our wider implication is that multiple molecular phylogeographic analyses
of unrelated taxa may help resolve apparent contradictions in patterns of endemism,
thus greatly improving the efficiency of conservation actions.
11.00 - 11.15
VIDYA, T. N. C., Prithiviraj Fernando, Don J. Melnick and Raman Sukumar. Centre
for Ecological Sciences, Indian Institute of Science, Bangalore 560 012, India, <tncvidya@ces.iisc.ernet.in>
(TNCV), Centre for Environmental Research and Conservation, Columbia University,
1200 Amsterdam Avenue, New York, NY 10027, USA (PF and DJM), Centre for Ecological
Sciences, Indian Institute of Science, Bangalore 560 012, India (RS).
POPULATION GENETIC STRUCTURE OF THE ASIAN ELEPHANT (ELEPHAS MAXIMUS) IN SOUTHERN
INDIA
We investigated the population genetic structure of the Asian elephant, Elephas
maximus, in southern India, using mitochondrial and microsatellite DNA markers.
Elephants were sampled in the Nilgiris-Eastern Ghats Reserve (NEGR) and the Anaimalai
Parambikulam Reserve (APR), which are separated geographically by a mountain gap,
and harbour populations of over 6000 and 1200 respectively. DNA was extracted from
fresh dung samples, and 590 base pairs of the mitochondrial D-loop sequenced. Five
microsatellite loci, EMX-1, EMX-2, EMX-3, EMX-4 (Fernando et al. 2001), and
LafMS03 (Nyakaana and Arctander 1998) were employed to assess autosomal variation.
Mitochondrial sequences revealed only one haplotype in the 118 samples from NEGR,
and two other haplotypes (n=12, n=1), differing from each other by a single base,
from APR. Analyses of microsatellite data showed that the two populations were significantly
differentiated from each other (FST=0.093, RST=0.055; P<0.05), but that there
was no differentiation among locations within NEGR (FST=0.016, RST=0.001; P>0.05).
Thus, data from both mitochondrial and microsatellite DNA point to a historical separation
between these populations, probably aided by the mountain gap. In addition, the absence
of genetic structuring within the NEGR population bears conservation implications
in terms of maintaining the reserve's connectivity by preserving elephant corridors.
11.15 - 11.30
SCHIKLER, PETER, Prithiviraj Fernando and Don Melnick. Center for Environmental
Research and Conservation (CERC), Columbia University, New York, NY 10027, USA, <pas@amnh.org>.
CONSERVATION GENETICS OF ASIAN ELEPHANTS IN SOUTHERN SRI LANKA
We report a population genetic analysis of Asian elephant, Elephas maximus,
mtDNA from southern Sri Lanka. Dung samples were collected from five locations consisting
of three national parks and two unprotected areas, all within a 30 km radius. A 537
bp segment of mtDNA encompassing a portion of the D-loop was successfully amplified
and sequenced for 98 samples. Compared to other regions, elephants in southern Sri
Lanka exhibit high levels of mtDNA diversity (measured as nucleotide and haplotype
diversity). Genetic differentiation and gene flow estimates indicate that elephants
in the five sampled locations constitute a single population. Current efforts at
mitigation of human-elephant conflict and elephant conservation in Sri Lanka are
mainly based on translocating and restricting elephants to protected areas. Systems
of electric fences currently being erected around protected areas in southern Sri
Lanka will fragment the landscape we sampled and prevent gene flow among the fragments.
Our results suggest that if fencing and fragmentation are unavoidable, elephant populations
inside and outside of protected areas in southern Sri Lanka will have to be managed
as a single metapopulation in order to preserve historic patterns of gene flow and
maintain a large effective population size.
11.30 - 11.45
FERNANDO, PRITHIVIRAJ and Don J. Melnick. Center for Environmental Research and
Conservation, Columbia University, 1200 Amsterdam Avenue, New York, NY 10025, USA,
<pf133@columbia.edu>.
A RANGE-WIDE CONSERVATION GENETIC ASSESSMENT OF THE ASIAN ELEPHANT
We report a range-wide genetic analysis of the Asian elephant, Elephas maximus,
using nuclear and mitochondrial DNA markers. The Asian elephant is considered endangered,
having lost almost 85% of its historical range. Current Asian elephant range is limited
to the South and Southeast Asian mainland and the islands of Sri Lanka, Sumatra and
Borneo. In our study, we sampled over 200 individuals representing 10 of the 13 countries
with Asian elephants. We PCR amplified and sequenced a mtDNA fragment that included
part of the D loop and two nuclear gene fragments (Von Willibrand Factor and Growth
Hormone Receptor). We also analysed variation at five nuclear microsatellite loci.
We found a wide range of genetic diversity with low levels of geographic structuring,
suggesting that Asian elephant populations have had differing population histories
but that they represent a single Conservation Unit and a number of Management Units.
We have used these genetic data as well as other important variables to delineate
appropriate management units for Asian elephants based on allele and haplotype frequencies
and to prioritise Asian elephant populations from a conservation genetic perspective.
11.45 - 12.00
Wheeler, J. C., M. Fernandez, R. Rosadio, D. Hoces, M. Kadwell and M.W. BRUFORD.
IVITA, Facultad de Medicina Veterinaria, Universidad San Marcos, Lima, Perú
(JCW, MF, RR), CONOPA, Los Cerezos 106, Salamanca - Lima, Perú (JCW, RR),
Consejo Nacional de Camélidos Sudamericanos, CONACS, Lima, Perú (DH),
Conservation Genetics Group, Institute of Zoology, Regent's Park, London, UK (MK),
Cardiff School of Biosciences, Cardiff University, Cardiff, UK, <BrufordMW@Cardiff.ac.uk>
(MWB).
GENETIC DIVERSITY AND MANAGEMENT IMPLICATIONS FOR VICUÑA POPULATIONS IN PERU
Microsatellite markers were used to study genetic diversity in 12 Peruvian vicuña
populations in national parks and isolated reserves. This project was carried out
to
elucidate the recent evolutionary history of wild Peruvian vicuña, evaluate
present-day genetic diversity and its partitioning in those populations, identify
demographically independent management units‚ within these populations and the likely
genetic effects of past and future management strategies, including the likely consequences
of sustainable utilisation practices. In general, we found relatively low levels
of genetic diversity within populations, but high levels of genetic differentiation
between populations. We identified four demographically distinct groups, those in
north western Junín, south Junín, central Andes (Huancavelica to Arequipa)
and Puno. Such groups could conceivably form separate management units for future
demographic augmentation within and between populations. Management implications,
and explanatory past biogeographical patterns will be discussed.
12.00 - 12.15
RAMAKRISHNAN, UMA. Department of Biology, #0116, University of California San
Diego, La Jolla, CA 92093, USA, <uramakri@biomail.ucsd.edu>.
ESTIMATION OF EFFECTIVE POPULATION SIZE IN SAVANNAH BABOONS USING INDIVIDUAL BASED
SIMULATION MODELS
Effective population size determines rate of loss of genetic variation, making it
an important parameter to estimate for populations of conservation concern. Some
mammal species, like savannah baboons, have extremely polygynous mating systems that
could lead to lower effective sizes. I use detailed demographic data and an individual
based simulation model to estimate the ratio of effective size to the number of adults
(Ne/Na = 0.51) for the population of baboons at Amboseli National Park. I use elasticity
analysis to show that Ne/Na is influenced more by male than female reproductive success.
Finally, I investigate sensitivity of Ne/Na to possible changes in the mating system
and show that less polygynous mating lowers Ne/Na by 16%.
The SCB2002 pages are maintained by Christine Eagle
email: C.M.Eagle@ukc.ac.uk
Conference email: scb2002@ukc.ac.uk
Last updated: 30.06.02