Slipper lobster’s charm and defense.

While diving at the island of Lesvos with the diving team of the University of Aegean we meet a ghost net. Ghost nets are the remnant of fishermen nets that left or lost at the sea. Unfortunately those nets are still able to trap some animals like the Scorpaena sp., sea turtles and slipper lobsters. This is the common name of the specie of lobster Scyllarides latus. These lobsters have instead of antennas and claw some strange spoon-like tools that help it to unstick his prey from the rocks. It usually feed with limpets. It prefers to stay all day in a shaded cover or an opaque shelter to a transparent shelter of the same dimensions. Lobsters also demonstrated a significant preference for shelters with more than one opening and for those that were in a horizontal as opposed to vertical position according to misters E.Spanier and G. Almog-Shtayer. Its noctural behavior is due to that most of his predators like Balistes carolinensis and Epinephelus marginatus are diurnal. If it’s being attacked it demonstrates a “burst-and-coast” type of swimming found also in some negatively buoyant fast-swimming fish according to Ehud Spanier, Daniel Weihs and Galit Almog-Shtayer. These guys also inform the scientific society as they research on slipper lobster swimming that its acceleration range between 250 and 500 cmXs^-2. In the results of the same research we can learn the interesting “This intermittent fast swimming is assumed to be used by lobsters to escape, especially through the back opening of their diurnal shelter in case a predator is successful in penetrating it. It is of short duration and is suggested as an emergency means in which the animal invests considerable energy resources to reduce its exposure time in an open area until it reaches an alternative shelter”.

All the above make the young environmentalist Elena being charmed by the strange lobster. We meet him moveless in the fatal trap of the ghost net. At first I thought it was dead but the still bright full coloration alert me that it was still alive. I used carefully my diving knife to set it free without harm it. If you ever try to do something similar remember that it can also harm you if your hand hit by its large tail. This behaviour have give it at Greek the name “kolochtipa / κολοχτύπα”. Elena fast felled in love with the lobster and started kissing it! It thanked us by pose for some pics.
Slipper lobster are easy to be catch by spear fishing divers and that has lead to being an overfishing suffering specie.

Running to the shelters!

.........................The presence of Elina alerts the hermit crabs.

As the naturalist approaches the sponge,he can notice a lot of tiny shells loosing their balance and falling down. In previous posts we saw the symbiosis (or the vicinity) between the sponge, mollusks and polychaeta. The structure of the sponge Aplysina aerophoba provides shelter also to the third major group of benthic fauna, the crustaceans. The little shells (except some Bittium sp) are the houses of the small hermit crabs. In the macro photo I think that you can see a young Pagurus anachoretus but it is too small to recognize. I was very impressed by the fast and simultaneous reaction of the tiny hermit crabs. As I got close to the sponge, at once all of them left their shell to fall from the walls of the sponge to the lower darker parts of the sponge. I don’t know if there is a possibility of communication between the hermit crabs, but what about the sponge? Sponges don’t have nerves but as an animal they find other ways to inform the rest of the body for what is happening. Maybe there is a sign by the sponge that can be recognized by the crabs? It’s very difficult to know but it’s nice as a scenario. Who knows maybe we learn in the next posts of the blog.

.......................................finally a successfull pic of the tricky hermit crabs!

Summer's almost gone but the celebrations continue.

Tomorrow is the beginning of autumn and as every time autumn begins, the summer goes away. As every time the summer goes away, we have to listen to the same song of the Doors .
Ok that’s enough with the matters outside the sea. When the autumn begins, all the virgos of the zodiac cycle celebrate. Unfortunately none of the animals of the eastern Mediterranean is virgin so we don’t have anything to celebrate. No? Of course not! If you look deep in the arthropods' classification, you can find a forgotten family of tremendous crabs called Parthenopidae. Parthenos is the Greek word for the virgin so in honor of this today we will introduce one of the most unknown families of the crabs of Mediterranean Sea. I have met crabs of this family 3 times and I think that all of them belong to the same species but yet I am yet unsure which species it is. I cannot find enough information about this family and this may be, because, these crabs don’t like the lights of publicity.
They prefer spending their time burried in the sand. That’s a pity for the naturalists as they cannot admire their impressive claws and their beautiful purple. The common name for these crabs is elbow crabs to fame their giant chelipeds . Maybe, if you compare them with the body size they are one of the biggest claws in the nature.
According to the Greek mythology, Parthenope was one of the sirens that were trying to seduce Odysseus with her song. Odysseus escapes from the trap and from her despair the siren falls into the sea and dies. The body of the siren washed ashore on a beach in the south of Italia and some travelers from Chalkidians that had just arrived found her. They burried her, and started to make their city around the grave. They gave the city the name Neapolis and this city is the famous untill our days as Naples. Annibale de Gasparis a scientist of astronomy, many centuries later named 11 Parthenope a small planet that he discovered as he was working in Naples.
Summer’s almost gone.

the hermitcloak or anemocrab?

In an older post we talked about the association of Dardanus sp. with the anemone C.parasitica. Now I will describe to you the most admirable symbiosis relationship of the Mediterranean, between crabs and anthozoa. Pagurus prideaux is a hermit crab that can grow up to 6cm and lives usually on the sandy parts of cave entrances. Unlike their great population in the Norwegian coast of the Mediterranean you cannot meet them too often here. When they are young they start to have a symbiotic relationship with the Adamsia carciniopados anemone. Because P.prideaux doesn’t feel very comfortable inside the gastropod shell, they prefer to live with “something like a shell” which the anemone helps to build. That way it doesn’t need to change its shell throughout his lifetime, as the shell grows bigger, along with the crab and the anemone. The anemone covers all the sensitive parts of the crab and the tiny shell like a cloak. The anemone is responsible for her buddies defence. For that purpose when they are in danger the anemone produces a lot of bright pink tentacles with stinging cells. These tentacles are called “acontia” (Second photo “where these animals are frightened the crab runs as the anemone spreads its stinking defence). The most noticeable thing in this relationship is the feeding behaviour. The crab feeds the anemone by putting pieces of food near the anemones mouth! It is possible, even after a few hours, the crab pulls the food out of the anemone’s stomach and eats it.

Remember, remember the 6th of December

One of the last pictures I took with my camera (before I violently drowned it, yesterday), was this wicked crab, called Dromia personata that is completely invisible unless it starts eating a jelly fish right in front you!



If you look closely on the middle left of the picture, you will see the side of the sponge crab under its well fitted sponge cover, grabbing the jellyfish by its tentacles and slowly eating it!


So there you see one crab, but the shock was the other one that is hiding behind the jellyfish! And both of them had the jellyfish clawed by both sides! Was it a well thought of attack?Do crabs like to eat jellyfish and work together to capture it?!
Both crabs had a 15cm carapace covered by a well attached sponge, making them COMPLETELY invisible!
These sponge crabs are very curious in that the front of their body is hairy, and the edge of its two front claws is bright pink. Although they may be pink they are huge and should be avoided...poor jellyfish

Crab duo...

Spidercrabs love anemones, and the anemones love the crabs. It seems that neither animals are hurt in this beneficial relationship, the crab is protected by the poisonous tentacles and the anemone is warned for any predators before anyone can suspect otherwise. You see, these crabs cannot be seen easily, you may be taking a picture of one and the other would be giggling behind a tentacle! Amazing camouflage and very hard in identification, unless the carapace is available for closer examination, for example when the crab is shedding. Maybe next time...I know where you live....
Sometimes they like to cover up with sponges, like another resident of Kalogria which will be on the next post.
Until then happy crab hunting!




Photo taken on this last Sunday of November in Kalogria.

Intertidal hermit crab.

Clibanarius erythropus is famous for a variety of reasons such as his funny name, the big range of shells and his usage as a bait. The last reason happens because it is very easy to trap him in the rockpools where it uses to sit. It has a foraging behavior and it selects substrates where there are a lot of filamentous algae and corticated macrophytes to eat. It moves big distances per day and research showed that the type of shell that it uses influences the extent of movement. In the video you can watch a strange meeting of hundreds of hermit crabs under a rock. Probably this happens for the reproduction. I made it in very shallow water (o,5m).

Greater Mediterranean hermit crabs

As most species of crabs Greater Mediterranean hermit crabs are susceptible to fights. Here you can admire the impact of Mike Tyson to the animal kingdom. (Video by Kostas Milonakis, unidentified if they are D.arrosor or D.calidus)


Dardanus calidus with some Calliactis parasitica on his shell.

Dardanus calidus

When you diving at Mediterranean you can meet two species of Big Hermit crabs (Bernard-l'ermites). The species Dardanus arrosor and Dardanus calidus can grow more than 6cm and both can be symbiotic with the anemone Calliactis parasitica. Unlike with the parasitic symbiosis that this anemone has with the Atlantic Hermit crab Pagurus bernhardus it is confirmed that D.arrosor assists the trasfer of C.parasitica to its shell. Also the same experiments showed that most of the D.arrosor that had accepted C.parasitica to their shell were females and males prefer to be on their own.

The marble hermit crab.

Crabs like this can run with unexpectedly quickness for Hermit crab like the one above.

It seems that it tastes good.

Most crabs are very possessive about the area that they living. That crabs prefer live at high populations in small areas and fight each other all day. In the photo above the two big ones fight while the small watching.

They also burried under the sand for cover. They have different sized claws and the one seems to be very big for their body size. They seem to pull the big claw like a torture.

All photos taken at Kolimpithres Paros at May09

Καρτσινάκι ή Πάγουρος

-They are used as a bait.
-They are climbing at sea grass and other sea inhabitants.
-Pagurus anochoretus may be a group of species.

Σιδεροκάβουρας

-They usually are night active but sometimes you can meet them also during the day.
-Photo taken from N.Euboic gulf (N.Artaki) at december 07.