While I was looking for snail fur, I stopped to take other photos:
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| A pair of channelled dogwhelks. |
They're usually busy eating barnacles, but for one day, they hung out together on the glass. All day. One is still there; the other is back at the barnacles. Spring is coming; I'm going to be looking for eggs soon.
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| Japanese rocksnail, Ceratostoma inornatum. I think. |
I find shells of these on all our beaches these days, easily identified by their thick lips and narrow opening. For a while, I brought some home for my hermits. They absolutely refused to use them. Any other snail shell from the beach is fine. Unfortunately, most of the ones I find on the upper beach are these.
I wondered about this; why are the hermits so dead set against just this species? Could it be because this snail is an import, an invader, not one the hermit clans grew up with?
It's a carnivore, like the dogwhelks, but it prefers oysters. Young oysters; it occasionally tries to drill through the heavy, mature oyster's shell in the tank, but gives up after a while and eats another mussel instead.
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Mientras buscaba pelo de caracol, me detuve para sacar fotos de otros residentes del acuario.
Primera foto: dos caracoles marinos, "dogwhelk", depredadores que comen bálanos. Estos dos casi siempre están ocupados en los bálanos, pero por un dia, todo el dia, se quedaron quietecitos juntos. Hoy, uno ya está de vuelta con los bálanos; el otro duerme en el vidrio. Viene la primavera; voy a estar buscando huevos de caracol un dia de estos.
Segunda foto; otro caracol depredador; este come ostiones. Encuentro sus conchas en todas las playas en estos dias; se identifican facilmente por los "labios" gruesos y la apertura angosta. Por algún tiempo, las traía a casa para mis ermitaños, pero se rehusaron totalmente a usarlas. Cualquier otra concha que les traigo está muy bien. Mala suerte, para ellos, es que la mayoría de las conchas que hallo en la parte superior de la playa son de esta especie.
Me preguntaba porque sería que justamente esta especie no les gustaba. ¿Sería tal vez porque este caracol es importado, un invasor, y no uno con que los ermitaños locales se desarrollaron?
Es carnívoro, como los primeros, pero prefiere los ostiones. Ostiones jóvenes; de vez en cuando trata de taladrar la concha del ostión grande en el acuario, pero después de un tiempo de trabajo futil, se aburre, y va a comer un mejillón.
> Could it be because this snail is an import, an invader, not one the hermit clans grew up with?
ReplyDeleteThat's my bet too. Hermit crabs have spent thousands of years evolving in sync with the snails they share the beach with. They need to be able to grasp the shell securely, and scoot inside to safety at the slightest flicker of a predator. I don't know how big your dogwhelks are, but the ones I've seen are much bigger and chunkier than the largest hermit I've seen, so there's that, but there's also the shell's protrusion at the front that might awkwardly knock at the hermit's head.
I hadn't thought of that awkward head issue. Worn on an angle, it could also interfere with the legs.
DeleteMy larger hermits wear shells even a bit larger than the whelk shells I find on the beach, but never this species.