Emperor said:
I suspect the 20 odd days between the beachings in Tassie and NZ and the quakes is too great a lag time but I thought I'd throw it out there.
Emps, a VERY interesting connection!!
Mesonychoteuthis is known from the Macquarie region, and
Gonatus is also abundant at this locals (retained in trawls - pers com. George Jackson some years ago). I had been quietly thinking away that one of the last places that these whales had been feeding had been this far south (off Macquarie Island), but I didn't know enough about the whales migratory patterns to know whether this was possible (and was going to look into this in coming weeks).
What would really clinch this for me would be to identify some benthic octopus beaks in the stomachs of these whales, but there is none - not one - zip even! The octopus fauna of the Macquarie region is quite different from that off New Zealand (especially cirrates), but the only octopus thus far found in the stomachs is
Haliphron atlanticus (aka
Alloposus mollis). I still cannot figure this out - how an animal (whale) can have a mix of Antarctic and subtropical/tropical (
Haliphron) species in the stomach - from which direction had it been migrating (North to South or South to North). The alternative is that
Haliphron is more abundant in or proximal to New Zealand waters (particularly South of New Zealand) than was earlier recognised (but we've only just recorded the adult from here, based on a single specimen). Moreover, the
Haliphron beaks in these stomach contents are not large - nowhere near the size of the adult recorded from here - and as subadults/juveniles are usually far more common (in trawls, and dictated by population dynamics) I would have expected them in collections by now. So, where have the whales been feeding? [Perhaps migrating North from the Antarctic into southern Tasmanian/Australian waters, then East to New Zealand where they stranded???]
A colleague here has been taking tissue samples from these stranded whales; I'll trundle on over and have a word with him when uni starts up again next year to see whether genetic markers are telling him anything about the whale migratory patterns. It would be sensational if someone had been marking these things with satelite tags so that the actual migratory path could be determined (and for the male and female this is likely to be quite different).