Since vent fauna is specifically adapted to live at hydrothermal vents it is unlikely that migration occurred across oceans using the shortest distance between vents.  Instead the migration seems to have occurred along the spreading ridges of the world.  Scientist are still unsure how microbes and fauna locate a new vent when one starts up.

Species shared between vent sites

	Galapagos	EPR 13	EPR 21	Guaymas	NE Pacific	W Pacific 1	W Pacific 2	Atlantic
Galapagos		43	42	13	7	3	3	0
East Pacific Rise 13deg N	43		54	11	3	4	2	0
East Pacific Rise 21deg N	42	54		11	5	3	2	0
Guaymas  East Pacific	13	11	11		6	1	1	0
Northeast Pacific	7	3	5	6		1	2	0
West Pacific Marianas/Japan	3	4	3	1	1		9	0
West Pacific Lau/Fiji/Manus	3	2	2	1	2	9		0
Mid-Atlantic	0	0	0	0	0	0	0

This theory can be seen in that some vent sites are closer in the pacific ocean.  The Galapagos site is further away from 21N East Pacific Rise than the Juan de Fuca  vent sites.  Using ocean spreading ridges though the Galapagos vent site is closer to the East Pacific Rise than the Juan de Fuca vent sites.  This is reflected in the fact that the Galapagos and Eastern Pacific rise sites share 42 species while the Juan de Fuca and Eastern Pacific Rise sites share only 5 species.

Only 5 species are known across the pacific two polychaetes, a limpet, a mite and a copepod.  Only one species is shared between the Pacific and Atlantic oceans this is a copepod.  The main reason for the differences between the Pacific and Atlantic is that there has been no recent ridge connection between the Pacific and Atlantic oceans.  Little is know of South Atlantic or Indian Ocean hydrothermal vent fauna but is predicted that they will provide the overlapping links of species that will lead to clues of the migration of vent fauna around the world.

Sources: V. Tunnicliffe

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