24 Nov 2011

3..2..1.. take-off

“We're all familiar with birds that are as comfortable diving as they are flying but only one family of fish has made the reverse journey” inform us “The Journal of Experimental Biology”. Reading more about an experiment done at Seoul answers all the questions that query us when we first watched the flyingfish’s flight over the sea. At the work of two scientists of Seoul National University ,that made the aerodynamic experiments, we can read all that interesting things.
"For the first time, we have performed a direct wind-tunnel experiment to investigate the aerodynamic properties of flying-fish flight and provided qualitative and quantitative data for the flying fish flight. Force measurements were performed for the real flyingfish models with different wing morphologies. The aerodynamic performance of flying fish is comparable to those of various bird wings, and the flying fish has some morphological characteristics in common with the aerodynamically designed modern aircrafts. As the lateral dihedral angle of the pectoral fins decreases, the lift coefficient slightly increases. In addition to the enlarged pectoral fins, the large pelvic fins have an important role in enhancing the lift-to-drag ratio and longitudinal static stability. The enhancement of the lift-to-drag ratio from the pelvic fin is attributed to the jet-like flow existing between the pectoral and pelvic fins. For both solid and water surfaces, the drag coefficient decreases and thus the lift-to-drag ratio increases as a result of the ground effect, indicating that the flying fish obtains substantial advantages by gliding close to the sea surface."

Nelly didn’t expect such a rare meeting while she was ascending from a dive at Kardamili region at Southern Greece. Usually she met jellyfishes or schools of small fishes in similar situations. Suddenly she thought that a bird splashed down over her bubbles trying to catch one small fish that moved carefree near her surface. Watching better she thought that the world had turned upside down (like at the POC 3 movie) and the birds come underwater! Ohhh look that fish it has enormous fins that look like wings tried to say at her buddy who swam nearby her. She realized that she was watching a flying fish, a fish that she had first met while fishing with her grandfather when she was child. Fastly she took some very nice pictures and later shared them at the social network. There I saw the pictures and that make me excited because it was the first time that I saw a u/w picture of a flyingfish. That fishes rarely come near the shore to make company at divers as they prefer the open sea. I find it hard enough to descry which specie it is because at Greece there are several similar species of flyingfish. I think it’s the Cheilopogon heterurus but as far as I search I cannot be sure. Thank you Nelly for sending us that pic!

5 Oct 2011

Return of the fire worm!

The time has come...summer is gone and the return to the city is inevitable for most people.
At this point, underwater, Eastern Mediterranean Inhabitants are enjoying the tides of calmness and quiet that comes with the migration of the masses of people, back to the cities and away from the sea. In this photo sequence we can clearly see how the worms enjoy a good stretching after the busy summer season...I suggest to all city inhabitants, take a deep breath, do your stretching exercises and get ready for a winter full of surprises, both on the land and sea!

Fire worms are one of the few dangerous species in the sea, as you can imagine by their name, also called brisstle worms dew to the white bristles covering the sides of their body. When waved at (wafting!) these bristles are extended (puff out), and if touched they can cause a burning sensation. If this should happen you can try to remove some of them with cello tape but you will not be able to remove all of them. The worm is composed of 125 segments (no wonder they can stretch out so much), each possesing 2 tufts of white bristles and one pair of red, branched gills.
They viciously feed on anemones and Tubastrea corals, however they do enjoy a good scavenge, as Hector blogs here http://medi-sea.blogspot.com/2009/06/and-more-kinky.html

5 Sept 2011

For our Fathers...

This post is dedicated to the memories of Hectors' Father Socrates, and my Father, Makis. They are the people that first introduced us to the glory of the Sea. Both of them were passionately in love with her. Every moment of their leisure time was spent by her side, being active fishermen and seamen. We continue to dive for their memory, my Father passed away 12 years ago and still to this day I dedicate every jump into the water to his memory.
Socrates died yesterday.
May he rest in peace, we will always remember him.
In the days our Fathers explored the Sea, the sight of big fish from the Grouper family was very common with fish reaching massive sizes. Nowadays it is very rare to see big specimens unless you are lucky to visit Marine Protected Areas, or other remote areas that have not been overfished. This photo of the Dogtooth Grouper was taken in North Greece and is far from the maximum size of 78kg reported as the maximum weight in Fishbase.org. The inquisitive fish on the right corner is of course a very common Eastern Mediterranean Inhabitant, the beautiful Coris julis, but he will have to wait for his turn on a separate post.

21 Aug 2011

Tropical colors beneath the Big Blue!

Underwater Greece reminds me of Underwater Caribbean scenes, breathtaking beauty, colors and vibrant life emanating from magnificent rock reefs that appear out of the depths. Here we see a characteristic school of Anthias anthias fish,which although hard to believe, are members of the grouper family (Serranidae). This relatively large, diverse family contains some of the largest of all the bony fishes, as well as some true Lilliputians. The anthias belong to the subfamily Anthiinae. Most of the members of this subgroup are small, colorful reef-dwellers that form groups or shoals over the reef where they capture minute food items carried by ocean currents. The subfamily includes 17 genera and approximately 170 species. In the Eastern Mediterranean, the only representative, Anthias anthias decorates reefs and pinnacles between the depth of 20 - 200 m and prefer to feed on crustaceans and small fish. They are typical serranid fishes in that they are protogynous, born as females and switch to a male mode of existence later on in life!
Within the anthias shoal, territorial males perform acrobatic U-swim displays and vigorously defend an area of the reef and an associated harem of females. Within the group of females, a dominance hierarchy exists, with larger individuals dominating smaller conspecifics. If the territorial male should die , the dominant female in the harem changes sex (they are protogynous hermaphrodites) in as little as two weeks and will become the new territory holder. To maintain dominance, males and larger females display at, charge, chase and sometimes nip at their neighbors.
Sexual dimorphism is evident with the males having yellow tips on the third dorsal spine and pelvic fins.

Looking closer in the frame (cropped from above photo) you will notice a spectacular Chromodoris luteorosea nudibranch being thoroughly investigated by the curious female Anthias. I had never seen this nudi in Greece before, and was very happy to encounter it unexpectedly! Its distribution reaches the Med and the Atlantic, and as most nudis it is a voracious predator.
This photo was taken during marine surveys in Kalamitsi and very soon to come, a big suprise from the depths of Pelion, while diving with Pelion Diving School.

13 Jul 2011

Is it a Nudibranch? Is it a sea slug? No! It's a mesogastropod!

Right in the center of this photo you can see an ovular animal of beige/white colour. It is very small, up to 15mm and is most usually found on gorgonians Eunicella and Paramuricea spp. It's color depends on the color of the animal it is found on, from yellow to red or beige. However, the color changes on the mantle of the snail, the hard shell always remains a brilliant, glowing white. When Neosimnia picta is threatened, it retracts its mantle inside, exposing the outside shell (here visible as the white descending line in the middle of the animal). This mesogastropod is quite elusive, probably using pigments of the host gorgonian to change the color of the mantle, making it merge completely into the background. This photo is quite rare in that the snail was found on the substrate and not on the gorgonian! For its size, moving from one gorgonian to the other can be a long migration, but don't worry! It can move with surprising speed and reaches as far as 80 m! This animal was found on 35 meters in Kalamitsi, Chalkidiki.

25 Mar 2011

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.

21 Feb 2011

The fish that fishes....Το ψάρι που ψαρεύει!

The biodiversity of fish shapes and forms reminds me of the
immense shapes and forms found in the rain-forest insects!
This month we offer for your viewing and icthyological pleasure
the magnificent Angler fish or Peskandritsa in Greek.
Another synomym is the Monk fish, with the females of the species
reaching the spectacular length of 2m, 40 kg!
To encounter even a small specimen is a fantastic experience,
firstly because of its mouth, which basically makes up most of
the body! The angler fish gets its name from a small fishing appendage
found on the top of the head, which originates
from one of the three modified dorsal spines.This fishing lure
attracts mostly small fish, however the angler fish with its
massive mouth can engulf fish as big as itself, and digest them easily in its expandable stomach! On the first photo we can clearly see the seaweed like
appendages, circling the mouth which can change color depending on the
environment, making this fish another master in camouflage, whether it is
lying on sand or rocky bottoms.
Another strange aspect of this animal is the use of its modified pelvic and pectoral fins as legs, which it uses to move around, along with a sudden burst of its tail.
On this video provided by our good friend Michalis, you can see this behavior on minute 2. The monk fish is highly commercial, however its status is not evalluated yet for the IUCN red list. It is always sold skinned and without a head, so basically
what you eat is the tail... not a lot from such a big fish, so it is best left alone
lurking on the sea bottom, fishing other small fish or even sea birds!

1 Jan 2011


In the past year we have witnessed many wonders of the sea and felt many sorrows from its continual demise.
We want to start the new year with a celebration of life a new way a new life
and exorcise the negativity and abuse we impose on the environment and ourselves.
Real change in the world can start only from within, deep within!
I made this video from pictures of dives made in 2010, memories that last a lifetime