Print

[Randy Conrad]

This morning I was enlightened by the topic of interest in regards to coconut crabs and their ability to carry off small and big bones. For quite some time now, I've personally been in debate as to their ability to "just" carry off a major bone of an animal or human. In the expedition video on YouTube, I was really amazed at their ability to do just that...But, my main question is how far will they carry these bones and take notice in this video how they interact with one another as they drag bones into an area where they migrate. It's like they have a way of communicating with one another as they feast or prepare to feast. Another question I have in regards to bones being dragged off of the 7th site is "Do they eat the entire bone when they drag it back to their lair or burrow...or as mentioned eat all the juicy juice out of the carcass or remains"? I'm trying to understand what the main purpose of dragging a bone back into a lair or burrow when it doesnt serve a given purpose for survival. Especially, when it looks like it was cleaned off at the time of death. Another question to ponder about is if indeed bones were found during Gallagher's visit to the island...how come...they didn't find the rest of the bones? I mean if these coconut crabs have the ability to walk off with bones...then technically nothing should have been found...But they did find an array of bones So the question is...where are these bones at? Also, a question for the experts is if a human bone was to have been carried off by a coconut crab 70 years ago and buried in the sand...would it still be there and in what condition?



http://www.youtube.com/watch?feature=player_embedded&v=h4ggAu9IsQw

[Chris Johnson]

This morning I was enlightened by the topic of interest in regards to coconut crabs and their ability to carry off small and big bones. For quite some time now, I've personally been in debate as to their ability to "just" carry off a major bone of an animal or human. In the expedition video on YouTube, I was really amazed at their ability to do just that

Wasn't it one crab, a land crab that did it?

Another question I have in regards to bones being dragged off of the 7th site is "Do they eat the entire bone when they drag it back to their lair or burrow...or as mentioned eat all the juicy juice out of the carcass or remains"? I'm trying to understand what the main purpose of dragging a bone back into a lair or burrow when it doesnt serve a given purpose for survival.

I've wondered if it was to do with the drought in 37/38 so animal instinct made them take back food for storage to eat later.  This could be a form of behaviour that isn't seen often.

Another question to ponder about is if indeed bones were found during Gallagher's visit to the island...how come...they didn't find the rest of the bones? I mean if these coconut crabs have the ability to walk off with bones...then technically nothing should have been found

My view on this is either 1. Gallagher's search wasn't as extensive/intensive as we like to imagine and 2. Finite number of bone carrying crabs.

As an aside I know that in the video they remove some of the bones so that the crabs can do their stuff more easily (time constraints)  we don't have a true picture of how long it would take a pack of crabs to fully disarticulate a body and more crucialy if the bones found by Gallagher were dispersed around the site or in one place like a museum exhibit

[JNev]

I tend to think that coco crabs are probably rather like most predators or scavengers and are opportunists. As such I suspect they will consume on-site when safe to do so, but will try to hoard away what they feel they must to have it for themselves (and thereby need to keep from competing creatures). 

I also suspect that 'need' is always with them, that a potential meal squandered = death, so basic survival probably drives all the above.

I'm no zoologist, so that's just a layman's view and set of guesses, but it seems to fit what we observe about these critters.

Would they 'gnaw' on a dry bone like a dog might, until it's gone?  I have no idea - but wonder if there's a particular need to do so.  Dogs seem to gain something other than nutrition from that - maybe dental health or promoting of enzymes to deal with carrion - just guesses.  Do crabs have that need?  Again, I 'suspect' crabs would pick a bone clean and then move on to the next 'juicy-juice' opportunity -

So, who knows, maybe Amelia remains a 'woman about town' on Niku to this day, her bones just awaiting the right thorough search so as to be found wedged into some long-gone coco crab's lair...

[manjeet aujla]

I think during one of the niku expeditions, an intrepid member of the landing party went hunting for the bones, by following the crabs to their burrows, and putting his/her hand into them to feel around. Maybe not too scientific, and prolly a longshot after all these years, but it could have worked. I don't know is he was a volunteer....lol

[Tim Gard]

The videos I've seen of the coconut crabs suggest their motivations are unpredictable.

In one, a puppy tries to play with one. The crab seems to go through long pauses of indifference, even when the puppy is up close, personal and well within striking distance ...

https://www.youtube.com/watch?v=0tM_9DFeTB0

Other footage shows them becoming bored easily, even when it  comes to securing dinner.

I think of it like the feeding patterns of animals in the wild. I've seen goats walk right into the middle of some prime feed, trample all over it, befoul it, then wander off to do the same thing elsewhere.

Lions eat the easy parts of a carcass and leave the rest for the subspecies.

So it wouldn't surprise me if the crabs ate while they happened to be nearby, then once it was out of sight lost cognizance of same.

 
 

[Randy Conrad]

Ric....I was just reading an article on Coconut Crabs and it mentioned that Coconut Crabs are attracted to little shiny objects such as necklaces, rings, or whatnots. Kinda curious if you and the team didnt do any metal detecting near any burrows. I also read where a coconut crab lives up to over 30 years. So really curious to know if possessions of Amelia's might be in one of these burrows!!

[Ric Gillespie]

Ric....I was just reading an article on Coconut Crabs and it mentioned that Coconut Crabs are attracted to little shiny objects such as necklaces, rings, or whatnots. Kinda curious if you and the team didnt do any metal detecting near any burrows. I also read where a coconut crab lives up to over 30 years. So really curious to know if possessions of Amelia's might be in one of these burrows!!

Yes, we have metal detected around all the crab burrows we can find.  No luck.  As I understand it, nobody really knows how long Coconut Crabs live.  I've heard as old as 70 years or more.  They keep growing and, after a while, reach a size where they have no natural predators (except humans). 

[Jimmie Tyler]

  I found this Biological Study of the coconut crab months ago. http://www.guammarinelab.com/publications/uogmltechrep66.pdf   It is pretty informative about the life of Birgus Latro!! It may help to answer some questions.