The video is the actual video from my research group’s dive with a remotely operated vehicle in the deep Gulf of Mexico. The background on all this alligatorfall project and why a bunch of scientists would sink an alligator in the first place is in our previous post. You can also read Atlas Obscura’s great write up on our work.

The post The Video of Giant Isopods Eating an Alligator in the Deep Sea You Must Watch! first appeared on Deep Sea News.

With the first taste of palolo I understood the Samoans’ love for it. Certainly it suggested a salty caviar, but with something added, a strong, rich whiff of the mystery and fecundity of the ocean depths.

—R. Steinberg. Pacific and Southeast Asian cooking. Time-Life Books, New York, 1970 (opening quote from from Schulze 2006)

This is not a picture of squid ink pasta. This is a picture showing writhing, detached body parts of polychaete worms (“palolo”, a.k.a. genus Palola), considered a delicious delicacy on a number of Pacific islands such as Vanuatu and Samoa. I’m told that “worms are enthusiastically gathered with a net, and are either eaten raw or cooked in several different manners”, and that “hardcore palolo connoisseurs grab the wriggling green-and-blue worms and swallow them raw on the spot”. Palola worms carry out mass nighttime spawning during summer months in the Southern Hemisphere, prompting a collection craze across Pacific islands from October – November.

I didn’t know this was a thing. I’m all about the invertebrates, but I think I’m going to stick to eating shellfish and shrimp. Two reasons: First, I’m not the kind of person that can stomach this type of cuisine. The spaghetti-like mass that islanders collect is not the actual Palola worm itself, but a dense package of sperm and eggs that detaches from the main body before spawning (the “epitoke”). “..as thick as vermicelli soup..the water is milky with mucous” is not a description that whets my appetite. On the contrary, it makes me wonder whether someone has thought of making a Palola-themed adult movie.

The second reason I’m staying away? These worms are listed on the IUCN Redlist of Threatened species–local extinction of Palola species has been observed in some places as a result of overharvesting. These worms have immense cultural significance for native Pacific Islanders, and I’d hate to be a food tourist contributing to an unsustainable fishery (since eating palolo inherently reduces the potential reproductive success of these polychaete species).

But mainly, after watching this video of epitokes, I just can’t even. And also, because it apparently tastes “a little scratchy.”

References:

Schulze, A. (2006) Phylogeny and Genetic Diversity of Palolo Worms (Palola, Eunicidae) from the Tropical North Pacific and the Caribbean. Biological Bulletin, 210(1): 25-37

The post I prefer my seafood without sperm, thank you first appeared on Deep Sea News.

Off the Angolan African coast, these researchers document one whale shark and three ray carcasses at 1200 meters on the seafloor.  This is the first time any of these have been documented as deep-sea food falls and only recently have living whale sharks even been documented off Angola.

Despite one of the carcasses being covered in 54 eelpouts, a considerable amount of flesh still existed on the carcasses.

[in prior studies] When presented with elasmobranch and tuna bait on a baited camera trap, scavengers clearly preferred tuna and only consumed the elasmobranch once the tuna was gone…Repeated experiments in this region using [bony] fish as bait showed a 10-fold increase in scavenging rates compared to that when elasmobranch was used.

So why in a food desert like the deep sea would fresh meat not be consumed quickly?  Apparently, elasmobranch, i.e. shark and ray, flesh is bit unpalatable and tough to chew.  The tough, sand-paper-skin may prove a formidable barrier to scavenger jaws.  The high ammonia content of elasmobranch flesh may also be, to say the least, unappetizing.  The carcasses may also smell like death and deter other scavenging elasmobranchs.

Other uncharacterized chemicals that are found in rotting elasmobranch flesh (necromones) have been proven to strongly deter shark scavenging and invoke an alarm response, even among different species of elasmobranch. If this phenomenon extends to deep-sea scavenging elasmobranchs, it can be assumed that the Portugese dogfish, Centroscymnus coelolepis, would have been deterred from scavenging the elasmobranch carcasses. This will have severely hindered utilization of the carcasses by other species, since C. coelolepis is the dominant scavenger off the Angola margin.

Yet despite the smell of death and urine, a dead elasmobranch still provides an essential snack in the deep sea.  The researchers estimate that these elasmobranchs represent 4% of the total amount food that sinks to the seafloor off Angola in the form of marine snow.

Higgs, N., Gates, A., & Jones, D. (2014). Fish Food in the Deep Sea: Revisiting the Role of Large Food-Falls PLoS ONE, 9 (5) DOI: 10.1371/journal.pone.0096016

The post Dead Elasmobranchs on the Seafloor are Not as Appetizing as One Might Assume first appeared on Deep Sea News.

Now this same group filmed swarms of the snailfish Notoliparis kermadecensis nibbling at bait 7560 meters, the deepest for a locality in the southern hemisphere. You can see that video here.

Of course all of this reminds me of…

The post Deepest Fish On Film first appeared on Deep Sea News.