Baltic marine mammal population boundaries and phylogeography Morten Tange Olsen HELCOM Seal 8 Turku, Oct 2014.

Baltic marine mammalpopulation boundaries and phylogeography

Morten Tange OlsenHELCOM Seal 8Turku, Oct 2014

Harbour seal management units

Olsen et al2014Mol Ecol

Baltic harbour seals mtDNA

Gråsælen

Grey seal population structure

Grey seal population structure

• mtDNA– 226 modern + 50 historic samples– 435 bp control region

• Microsatellites– 79 modern samples– 14 loci;

SCOTLAND WADDEN SEA LÆSØ RØDSAND FALSTERBO CHR.Ø

SCOTLAND WADDEN SEA RØDSAND FALSTERBO CHR.Ø

Grey seal genetic diversity

-0.00499999999999997

3.03576608295941E-17

0.00500000000000003

0.01

0.015

0.02

0.025mtDNA nucleotide diversity

Location

π (9

5% C

I)

Danish historic (54)North Sea modern (71)Baltic modern (142)

Grey seal finds (15000-3000 BP)

Sommer and Benecke 2003

Grey seal finds (3000-500 BP)

Sommer and Benecke 2003

GreyHarbourRingedPorpoise

?

?

Changes in species composition (DK)

Atlantic

Atlantic-S

ubboreal

Subborea

l

Subatl

antic

1500-1888

1889-19270%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

RingedHarpGreyHarbour

Olsen et al, unpublished

Future studies• Combined genetic analysis of harbour, grey

and ringed seal, and porpoise• Population structure and divergence times – Geological events– Climate events– Environmental factors– Historic abundance and distribution

• Existing mtDNA and microsatellite data• Genomic data and ancient DNA