Digging for whale bones

Back in August 2011, three Blainville’s Beaked Whales Mesoplodon densirostris became entrapped on the fringing reef of Lord Howe Island lagoon. Onlookers noticed numerous Galapagos whaler sharks eating the whales, and by the time anyone was able to access the site, all three had died. The whales were then towed to shore where tissue samples were collected and they were buried.

Now, almost six years later, a team of Australian Museum scientists are on Lord Howe Island to excavate the bones.

“It's coming along really well," says Dr Rebecca Johnson, Director of the Australian Museum Research Institute. 

"One whale was partially removed by day three, and the others will follow close behind.

"The tails of two were still buried under a large amount of soil (we didn’t quite excavate a hole that was large enough) so we will probably have to get the diggers back to move that two-plus metres deep of soil. There is only so much you can achieve with a shovel!” 

So what took so long? Dr Johnson explains, “It is usual to bury large carcases as a natural way of cleaning bones. It was much easier to do this (bury them) in-situ rather than transport three 4 metre-plus whales back to Sydney.

"We have since discovered they (the carcasses) probably don’t need to be buried so deep (this also makes excavation much easier) and that they can basically be ‘composted’ with natural materials if they are covered up by something like a tarpaulin." 

So why collect?

After 190 years of collecting, the AM has acquired more than 500 whale and dolphin specimens for its collection. These specimens offer a wealth of scientific information, and their study has drastically improved understanding of whale populations. 

And while its unlikely these new additions will be seen suspended from the roof of one of the AM's galleries, their potential to aid species research is vast.

“The bones are very fragile so unlikely to be of ‘display quality’. But because beaked whales are so unusual, these will be invaluable for scientific study.

"We will continue to work with the Lord Howe Island museum so both institutions can communicate information about these important and interesting animals.” 

The whale exhuming is one of several key objectives of the AM’s current Lord Howe Island expedition, which also aims to benchmark native and introduced animal populations and conduct a daring survey of the sheer cliff faces of Balls Pyramid in search of further specimens of the rare LHI Phasmid.