Brooding over new Bryde's whale relative

A population of Bryde's whales (pronounced, approximately, Broodus) in the Gulf of Mexico has been determined to be a new species: amazing news. It has received the common name of Rice's whale and may be over 13m in length. 

NOAA's official account, based on a paper in Marine Mammal Science, reports Dr. Patricia Rosel was the key figure in identifying these whales as a new species. It was her examination of a skull, compared via hundreds of measurements to known Bryde's skulls, that provided the final proof of the new whale's uniqueness.  

This capped off more than a decade of work by Rosel and several other scientists.  It all began back in the 1990s with the first observations, by Dale Rice, of what was thought to be a population of Bryde's whales. This group was unusual in that its range appeared limited to the Gulf, which was odd given other populations of this whale (already split into two species, a pelagic and a coastal type) had much larger ranges.  Subsequent work included DNA studies as well as examining skull morphology.  (In one of those incongruities that pops up in the study of nature, the measured whale, the type specimen, is an oddball that wandered all the way up to North Carolina, where it died and drifted ashore.)

So now we have the species called, formally, Balaenoptera ricei.

Dr. Rosel examining the skeletal remains of the type specimen (NOAA)  

Rice's whale is the latest in an astonishing series of discoveries. It's common, and reasonable, to assume we know all the cetaceans. They are big, they must surface to breathe, and we've been "collecting" them for centuries.  

And yet we have ten new species in the current century.   

We know of 23 species of the reclusive, deep-diving cetaceans called the beaked whales. The "23" is still approximate with such hard-to-study animals - some species might eventually be collapsed together, or new ones named. As shown with Rice's whale, it can take a lot of time and work to establish definitively that two similar-looking species are indeed different.

In December 2012, three cetologists on a Sea Shepard Conservation Society described what they'd found on a research cruise off the west coast of Mexico.  They took clear, closeup video and film records of what appears to be a new beaked whale species.  Even more interesting, the scientists involved were there looking for a different whale whose unidentifiable "voice" had been picked up on hydrophones.  This new species does not match that, so who knows what else is down there? 

The last new beaked whale before that (reported at sea by Japanese fishermen but not scientifically identified) washed ashore in Alaska only in 2016. It was formally described in 2019  as Berardius minimus. 

Now the bad news for Rice's whale: there are perhaps 100 of them.  That's not too small a population to to sustain itself, but it makes the species very vulnerable.  Their habitat is troubled by the usual nemeses of whales: ship collisions, entangling fishing gear, and noise pollution that makes communication and thus family/pod cohesion difficult.  More details are in a good NPR article here.    

If we have, as it seems, three sizable whales announced in the last five years, that's a strong indication humans have not yet catalogued all these intelligent, social, and fascinating co-inhabitants of the Earth.