Sept. 9, 2022

Hermit Crab

This podcast episode we talk about the Hermit Crab! Relax, unwind, and join me on the sandy beaches, where we learn all about these armored mobile-homes.


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hello everyone welcome back to relax with animal facts I am Steph wolf and today I am going to be learning with you about our furry scaly or possibly even slimy friends and in today's case I am not sure exactly where to place this creature because we are covering the %HESITATION so wonderful hermit crab with some of our creatures they just don't seem to fit in those categories of furry scaly and slimy but to this of course is a very special listener episode dedicated to Katie Carey N. G. O. D. and the big mommy Karen who wrote in the request with a review thank you all for taking the time to send in your animal requests and I hope that you enjoy your episode if you want your very own episode on the podcast and to learn about the cool creature at the very same time you can go to relax with animal facts dot com and click on the animal request tab and lastly you can always just send an email to relax with animal facts at G. mail dot com I look forward to getting your animal suggestions and don't be shy I respond to each and every one of them and I cherish each and everyone of them just before we hop right in and look around for some hermit crabs I just wanted to take some time to think and recommend cozy earth they make premium bedding and lounge wear and they are the sponsor of today's episode and I would never recommend you guys something that I didn't genuinely like they sent me a bamboo sheet set to try and I have never slept so comfortably than with those sheets if you were like me and hate to that very stuffy or suffocating feeling when you're in your room in your bed is too hot and you feel like some kind of an oven roasted potato their stuff is made from one hundred percent viscose from bamboo meaning they are sustainable extremely breathable and softer than cotton we sleep a third of our lives so investing in making that better makes a lot of sense they are giving the listeners of this show specifically you guys a thirty five percent off sitewide discount when you use the code animal facts at checkout that is over one hundred dollars off of your own bamboo sheet set thank you cozy earth for supporting the show I'm just going to say where I caught my facts from and then we are going to go straight into the episode I got my facts from National Geographic dot com A. two Z. animals dot com dip and dive dot com national zoo dot SIA dot EDU Carolina dot com and at him online dot com all of those resources are in the show notes or the description of this episode so if you want to check the amount and I encourage you to do so all of the relevant links are there and now I would like for all of you to notice maybe where you're carrying some tension is it in the head in the neck may be in the shoulders somewhere everyone here is different but we really don't need all of that tension where we are going and so I encourage you to right alongside me trying to relax those parts of your body that you feel are tensing as we go into this immersive experience together onto the sandy beaches where the hermit crab resides now keep in mind that while we are walking around on the beach today there are over eight hundred species of hermit crabs worldwide and almost all of them are ocean dwellers there are some meaning around a dozen semi terrestrial species and these species are the reason why we are on the land today and not scuba diving into the ocean the first thing about the hermit crab is that they are covered with a hard exoskeleton like that of many other crabs and there we have a word that we might or might not be familiar with and that is exitosa Kelton something key in that word is that prefix XO it means that the skeleton is external so the exoskeleton is an external skeleton that supports and protects an animal's body in the case of the crab that is exactly what their shell serves as the opposite of an exoskeleton is an endo skeleton which you and me have our skeleton is on the inside not on the outside so this tough armor will become slightly softer when it's around there very long abdomen because they do need to fit pretty snugly into a spiral snail shell it will press its abdomen it's fourth and fifth pairs of legs as well as its appendages at the end of its abdomen against the inner wall of the shell and contract its longitudinal muscles also we can fit in this wonderful shall that it calls home but one question is important in that is how do they stay inside of it why don't they ever just slipped out of it this is mainly due to the rough surfaces that are on the inside of the shell it will help hold them in place so they don't just slide out Willy nilly as they are walking around we are going to save the molting portion just for a bit later let's first spend some more time on the more general aspects of this wonderful creature they can be found in shallow waters pretty much all over the world about one thousand one hundred hermit crab species can be found worldwide of which almost all of them live in the ocean today however we are focusing on those species that are semi terrestrial because those are the ones that people seem to know the most about they are commonly known as land hermit crabs and they are commonly kept as pets by some most people seem to be familiar with the semi terrestrial species in contrast to the ocean dwellers so that is also one of the reasons we are covering these specific kinds of hermit crabs so as we learned just a little bit ago there are over eight hundred species worldwide of hermit crabs they can be found all around but there is only one fresh water hermit crab meaning that there is one special hermit crab of that huge pool of species that prefers not Salin aided waters but fresh water into this peculiar crab is found in Vinu at two this is a nation that relies in the South Pacific Ocean it comprises about eighty different islands but back to the more general hermit crab they are omnivorous scavengers they will each microscopic mussels and clams as well as eating things like micro algae so they E. both animal and plant material and although we will be covering the name hermit crab and what those words mean their name is not exactly apt to what they are first the hermit crab is not a true crab which means that they do not have a uniformly hard eggs %HESITATION skeleton and they cannot grow their own shall we learned that their abdomen is slightly softer than the rest of their body which makes these a peculiarity among other crabs but though they are not true crabs we can see why they warranted that distinction just from how they look they do have this curled tail with the hook that enables their bodies to fit inside of these borrowed shells and to stay inside those aboard shells and one of the most interesting things that they do has to do when a new shell arrives hermit crabs will form online biggest to smallest to see which animal will fit into this new shell the next smallest will then take that crabs handed me down and so on so we have a sort of direct thrift shopping from one another there's no exchange of paperwork between the hermit crabs they just hop into their new leased home and off they go the reason they were cold hermit crabs is more behavioral than anatomical or physiological they have a habit of sheltering in their shells and we will see you later we and we uncover the etymological origins of the word hermit why this is an apt distinction for the behavior the word hermit also seems to imply that they are something of a solitary creature but that is not true they will live in very large colonies of hundreds or more members where they will sleep piled up together and even collaborate in teams to find food nearby one question that might pop into your head when we were talking earlier about this shell swapping behavior and that might be if hermit crabs always play by the rules do they steal other shells and the answer is that sometimes they don't play by the rules but stealing shells is not very common behavior once a hermit crab grabs the deed of the shell itself it is often enough to dissuade any other hermit crabs from trying to gain occupation to their little mobile home but they may sometimes fight or even kill a competitor to gain access to a shell that it really wants but this sort of competitive behavior or maybe more agitated behavior does not really happen with hermit crabs of very different sizes it seems as though fighting for shells that they would never fit in is not their prerogative it is only when there are a great number of similar sized hermit crabs with fewer shells that you might see this happen they are so good at waiting in line for their shell in fact that they will wait for hours sometimes these shells if may be important to mention or also shells from mollusks hermit crabs also have reduced deals they're a little few chambers have these very highly vascularized areas in order to do great amounts of gas exchange they have stocked I which means that they are propped up in bed very familiar shape with acute division and they will also have two pairs of antenna these two pairs will have different functions with the longer one used for feeling and the shorter one which is more of a feathery sort of texture they will use for smelling and for tasting they also have sensory hairs that will give them information about their outside world that are a part of this tough exoskeleton these hairs will act as maybe tertiary kinds of N. ten nine as sensors for vibration around them so they really have some interesting things going on now let's talk about the process that is very significant and that is morphing malting is a process by which they will shed their exoskeletons and then create newer and larger ones to accommodate their bodies as they grow this molting process happens by pressure the build up a tremendous amount of water pressure in their body in order to split that old shell to accommodate the ongoing process some of them will leave their shell temporarily to bury themselves in the sand as the mold and some species will store water in there shall before the mold and then just remained there throughout the entire process which can take anywhere from forty five to one hundred and twenty days so here we can see that they are engaging in that behavior of sheltering in their shell as the mold which is why they were given the name hermit crab the retreat into the caverns of their mobile home and enjoy a good rest of forty five to one hundred and twenty days after that period when the molding process is finished they will continue on business as usual there is some criteria to fit whether or not this shell that they want to inhabit will fit the bill they're looking at the shell from a visual standpoint how does the shell look they will test the show for its move ability they will look at the texture of it they will look at the external shape of the shell the shells opening can also tell you a lot about it is it obstructed by something can the hermit crab actually get even in the first place they will see if it is comfortable for them to be inside of it the last thing they would want is to be flipped over like a turtle on able to get out hermit crabs seem to vary in their mating habits but we will focus on one here the carabiner hermit crab is one that lives in the wetlands but when it is time to mate will head for the sea shore in huge masses they will all go together like a mass exodus of hermit crabs the goal mate and reproduce amidst the chaos of armies of carribean hermit crabs males and females will find each other come partly out of their shells and the mail will transfer a packet to the female which will fertilize her eggs before the female carries her eggs to the edge of the water we're just the contact with seawater will cause the eggs to burst and the larvae to float away promising us a great bunch of amazing new hermit crabs in the future if hermit crabs male or female wish to communicate with one another they can do so by croaking or chirping sounds they can also rub their tail rub their body against the shell and so they make do with what they have to communicate in ways that they seem to understand now let us go to the final fact of the episode which is the name hermit crab where does it come from or rather what does it mean let's focus first on that word hermit it was coined in the early eleven hundreds or the twelfth century and was used to describe a religious recluse or someone who dwells apart from everyone else in a solitary place for religious meditation it goes back to French to lay flattened and finally to Greek era meet this which literally means person of the desert which comes from a similar Greek word that means a solitude or an uninhabited region so we can see why the hermit crab with names so considering that during their molting process they hide themselves away and close recluse in order to mold that second word crab we might be more unfamiliar with than the first and this word goes through many different transformations from Old English Dutch hi German and even Norse there is a Dutch word that I'm not even going to bother trying to pronounce but it means to scratch or claw the word crab really could have its roots as early as the thirteenth century probably from a Germanic Old Norse word so here we have one who dwells apart in the solitary place who scratches and claws and that is a very literal definition for the hermit crab from its etymology one eight cool cool creature now let us move on to the review portion of the show in which I read a review from one special listener and in today's case it is a review not coming all the way from somewhere at least for me it is in Canada though maybe for you Canada is far away the user V. Newson V. writes this podcast makes me laugh maybe unintentionally but it's very relaxing and I've learned a lot the host is very sweet and genuine thank you Wien for that very kind review I'm so glad the show helps you not only to relax and to learn but also to laugh as you said maybe when it was not my intention I will say that many a time my sense of humor is kind of embedded in two episodes in different places if you know where to look but in general I try to keep jokes to a very bare minimum regardless I'm very glad that you love the show and I'm equally glad that you are a big part of it if the show has been helpful for you the greatest way you can give back is by leaving a review it helps the show get better it helps the show grow I cannot tell you how much this show has changed and grown because of critical feedback that I have gone in so whether it is five store whether it is one store I would love to know what you like about the show or what you don't like about it this episode was a fun one who does not love a day at the beach if you want to join me on another beautiful beach to learn about the don't go on the island of Mauritius you can go on the patron on page relax with animal facts we are currently doing an extinct animal mini series we're so far we have covered the woolly mammoth the dodo in the Tasmanian tiger if you were looking for a link to how to get there it is in the show notes of this episode if you have an animal that you would love to learn about and you want your own episode you can send in your request through the Instagram page relax with animal facts by going to the website relax with animal facts dot com and going to the animal request tab and lastly you could always send an email to relax with animal facts at the G. mail dot com I look forward to your suggestions and I'm so glad that you join me on our journey today I hope that you will join me on the next podcast episode with the next animal take care