Yeti - O. briareus

Yeti is getting bolder sooner that I remember Cassy or Tatanka being at this size. I only see him at night but he comes our almost immediatly when the tank lights go out and has no fear of the feeding stick. If he does not like the offering he will either blow or push it away :roll:. I may have a little spoiled octo on my hands :oops:

I am worried Yeti will eat all his food before I can get more. He loves shore shrimp and seems to have caught all but one in the tank in addition to what I feed him (he almost got the last one the other night - made a good swipe at it and missed). The shrimp (by design) were really small and now he eats at least 4 a night. Fortunately, he begrudgingly takes a piece of thawed crawfish but refuses blue crab and regular shrimp. I can't order more shore shrimp this week because of the heat so I have my fingers crossed it will be shipping weather next week or I can coax him to take the crab meat (I have plenty of that).
I have not posted my creeping suspicions but watching Yeti's growth I am beginning to wonder about his species. Her/his growth rate seems slow (he has doubled in size now) but his eyes seem more prominent and the mantle longer and not as robust. He definitely looked exactly like an O. briareus when he came (with the telltale blue around the eyes and arm:mantle proportions) and he does show a mottled coloration some times (color unclear as I am viewing under red light) but mostly he looks brown and almost shiny. It occured to me that I have not seen many species this young and it is possible others look extremely similar. He could easily be the Atlantic long arm (which looks similar O.briareus from the pictures and video I have seen) but, as yet, shows no interest in the sand. Most likely, I just don't remember the details of my hatchlings :old:
I feel I have confirmed the "shell" thing in young octopuses. Yeti has totally refused several offerings of blue crab meat. Tonight I took a knife to an arm section and sliced several, mantle sized pieces (I could not cut them smaller) and offered her/him one on a stick. Unlike other times, he immediately grabbed it, put it under his webbing and was obviously manipulating it to be eaten. Last night I did the same with crawdad tail with similar results.

I wish I had more pictures, Yeti's mantle looks elongated and his eyes more Y shaped than I think O. briareus should show. I do think we are in a growth spurt so maybe he will start coming out in the day a little soon (his mantle is only about the size of a small woman's top pinky finger joint and not as big around(maybe an inch long) but his arms (very slender) might be as long a 7". Arms are always hard to guess, especially when they are wrapped in the LR and may or may not be streched out as they look in the rock for snacks.

Recently there was a study that indicated octopuses pattern after something nearby and not just the general substrate. Yesterday, I witnessed a camouflage behavior that would follow this thinking. Yeti was awake with the lights on (unusual as far as we know and it may have had to do with the fireworks vibrations). I happened to spot him because I saw something bright white where it should not have been at the edge of a cave. It took a few minutes to finally see his mantle (very darkly colored) even knowing something about his orientation but the arms were extremely white. Just above him on the opposite side of the cave was a dying/dead polyp cluster and growing down into the cave was an almost identically configured piece. Unfortunately, once he know I had spotted him, he moved back into his den before I could try for a picture.

edit: I did go back an take a photo of the object I say Yeti emulate. Notice the polyp that could be an octo arm on the right side of the cave. Yeti was on the left where you see two brissle worms. His/her arm matched the bright white of the polyp but the rest of him/her as dark, dark brown.



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I was pleasantly surprised that my night shots captured an image :biggrin2: The pictures are not great but far more than I expected. I changed the color tone so that the pictures were not glaring red :roll:


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I wish I had more pictures, Yeti's mantle looks elongated and his eyes more Y shaped than I think O. briareus should show.

I don't know. i see what you are sayiong about his mantle not seeming very much like Briareus, but i think he is one, I think he is just young and growing.
The pictures look more briareus than in person. His eye stalks are more distinct and raised than I think they should be and, even though he has doubled in size, I keep thinking he is growing slowly in girth. I think I am just imagining it but when I look at him I can't help but wonder if he will be really really small or is something else. :roll:

I took a chance with the flash after giving him a rather large (comparatively speaking) piece of crab (shell on) tonight. Unfortunately, The camera could not focus well into the abyss and even with help from my editor the clarity is poor. His colors are certainly briareus but I don't know if others can be similar. Every picture I have (not many) taken with flash of Cassy or Tank show the luminescent green speckles they are known for, none show arm stripes and the eyes are closer to the head and the head and mantle are more robust (the main things that have me wondering). The only other animal that I think Yeti could be is the Atlantic Longarm octopus, Macrotritopus defilippi.


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I'm probably going to regret (or at least be embarrassed) posting this but I am sticking my neck out and saying I don't think Yeti is O. briareus. His mantle always looks quite pear shaped and his arms are most fragile looking. Tonight I invited him to touch my finger and he reached out and pulled a little. He is not very strong and this seems to go with the fragile look. He IS very curious and climbed in, out and through his live rock to examine my offered finger. I am relatively sure he is a young octo and not an unknown dwarf. All the dwarfs I have seen have a much more robust mantle, his is very slim.

We tried offering shell on shrimp last night. He striped the shell off the shrimp in one piece while it was on the feeding stick but did not remove the shrimp. I could feel vibrations in the stick like he was biting it but there was no exposed stick under his webbing. He decided it was not worth messing with but did not run away or even blow it away when I tucked it under his webbing, he just refused to take the food. I swapped it for a piece of crab and saw him very tentatively touch his suckers to the meat part to test it before he decided it was edible :biggrin2: I still think that table shrimp may be too tough for the young ones even though this was a section near the tail that should have been tender.
Using Arm as Fishing Lure?

Yeti appears to use his arm as a fishing lure like an angler fish or is looking for microscopic food in the water column. I tried to video the behavior with little success. I did post a clip on YouTube but the upload changes make the action even more difficult to see. I have noticed O. mercatoris appearing to skim the water for food and LittleBit would turn upside down at the surface (presumably eating Cyclop-eze) but this is a different approach and looks like he is using his arms to attract live food. Tonight I used a flash and you can see the arm but the still does not really depict this unusual behavior.

I am convinced he is not O. briareus but am not at all comfortable with naming another species. I wonder if the apparent feeding behavior is related to having been a small egg animal but I have never seen it in others. Also of note, he seems to totally avoid the sand. His supper fell off the feeding stick and he zoomed down a level on the rock but would not go out onto the sand or even reach for the piece of crab. When reoffered, he refused it emphatically and I had to get a new offering before he would eat.



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Not much of a picture but significant! This is the first we have seen of Yeti during daylight (early evening) hours. He was not out long but I was able to give him a shore shrimp so we will not feed him at his normal 11:00 PM time tonight with hopes of being able to feed with the rest of the tanks around 7:00 PM.

I am still not at all sure on species but have relabeled him defilippi (Atlantic Long Arm) until I can come up with something negating the ID or find a better match. Of the videos I have seen, he reminds me of Ameloctopus litoralis but that species is smaller, not found in the Caribbean, has lower set eyes and has no ink sack. However, if you watch this video , Yeti's movements and general look are the same. Note how Ameloctopus molds to the substrate. One of the words Hanlon used to describe the one he kept was delicate and that well describes this little guy in there is not much to him. His arms are long but thin and his grip is not very strong. He was definitely a baby when he arrived and has at least doubled in size but I don't expect him to be as large as the smaller O. briareus and definitely not as thick in arm or mantle.


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Friday Yeti showed up as Neal was feeding the tank and slithered (only way to describe it) around on the far side (furthest from his den) to pick up pieces of shrimp from the substrate. When offered the same shrimp on a feeding stick he has totally refused to eat it. I have mentioned that I wonder if it is too tough to eat when they are small but something else crossed my mind when I watched the savaging behavior. His approach to retrieving the food was very much like that of the "Pesky" (red brittle stars are all named Pesky in our aquariums) that lives with him. Pesky's are often found in our octopuses dens but this observation was at the far side of the tank and Yeti and Pesky were together. This is particularly interesting in light of the suggestion that he may be the "Atlantic Mimic" and unproven suggestions that octos can learn from observation (non-repeatable study with conspecifics made the news some time ago. Additional observation suggests observational learning still may be a possibility in spite of the discounting of the original study)

Second daylight spotting at about 5:00 PM on Saturday (more than an hour before normal feeding time). Yeti was out at his normal 11:00 PM feeding time Friday night (after his scavaging and being given supper) but I did not offer food so when he showed up at 5:00 PM I gave him a crab even though it was early. Unlike previous delays and missed first attempts, he was so fast to "jump" off the rock, catch the crab and disappear with it into the live rock, I was not able to get the planned video :roll:.

However, I did get a couple of pictures before the food offering. Note the tiny white papillae. They looked much like the fish parasite commonly called ich (Ichthyophthirius Multifilis [/I). These are distinctive raised papillae and not just white spots). Reviewing Roger Hanlon's most recent video on O. defilippi, I see a similar look on the mantle as the animal digs into the sand and then on the rest of the body (but not the mantle) when it exits.

The second photo I shot for size perspective but did not get a full shot of the tank so he looks larger than what I was trying to capture.


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Nope, I am 85% sure he is not O. briareus (and 100% sure squid IS). However, there are a lot of features that are similar and he could fool me yet. Behavior is way different for one and, in spite of my effort, the perspective shot just does not show what I was trying to capture. I need your photography skills!
It took Yeti awhile to come out tonight but he was in position (across the tank from his den) at feeding time. Even at this size, the feeding stick is something that needs to be captured and he battled the urchin for the right. Note Pesky is being pesky on the sidelines :biggrin2:


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