In October, two oarfish mysteriously washed up dead on beaches in Southern California. It's unusual to find one intact oarfish carcass, so the fact that there were two within days of each other had scientists scratching their heads. While it was probably nothing more than coincidence, researchers quickly took the opportunity to study the intact critters. Chris Clarke wrote about that research at KCET ReWild, and BBC News created a video:

Rick Feeney, an ichthyologist at the the Natural History Museum of Los Angeles explained to me then that oarfish do sometimes wash up in bunches, sometimes a male and a female together. "What this means, we don't know." We do know that is has no connection to earthquakes, as some have suggested. It could be that oceanic currents are shifting, driving the oarfish closer to shore. "The standard reason researchers have given in the past is that oarfish get injured at sea by strong storms and then wash up inshore when they die," he added.

But that doesn't explain how participants on a Shedd Aquarium trip to Baja California found themselves watching two living oarfish swimming around in very shallow water:

It's a good reminder that the more we think we understand the deep, the more we realize we have so much more work to do.

Image: Oarfish that washed ashore on a Bermuda beach in 1860. The animal was 16 ft long and was originally described as a sea serpent. Drawing by R. Ellis in Monsters of the Sea, public domain. Wikimedia Commons.