Fish Fins
Fins are one of the most distinctive features of a fish and appear in several different forms. Each fin of a fish aids in its maneuverability and the ability to swim. Understanding the types of fins,  makes it easier for scuba divers, or snorkelers identify the variety of fish if they need to look-up their sightings after the dive.  There are five main fins on a fish that are commonly described in fish Identification.

• Pectoral
• Dorsal
• Pelvic
• Caudal
• Anal

Dorsal Fins
Dorsal fins are located on the back or on the top of the fish, and aid the fish in sharp turns or stops, and assist the fish in rolling.  Fish may have up to three distinct dorsal fins, known as proximal, middle , and distal  dorsal fins, however several fish have just two dorsal fins with the middle and distal fins fused together.

The type of Doral fins are:

• Single
• Split
• Pointed
• Trigger
• Spine Triangular
• Trailing

Tail Fin or Caudal fin
The Caudal fin or Tail fin is the primary fin of the fish that gives it forward propulsion and speed. For fish identification, the type of Caudal fin is used to distinguish one type from another. The main types of Caudal fins found in bony fish are:

• Indented
• Round
• Square
• Forked
• Lunate
• Pointed

Ventral or Pelvic Fins
The pair of ventral or pelvic fins located on the bottom front of the fish help aid in stability and slowing down the fish, or stopping it quickly. The fins also help the fish move upwards and downwards through the water.

Anal Fin
The Anal fin supports the dorsal fins by providing the fish with more stability in the water, controlling the rolling motion.

Pectoral Fin
Like the ailerons in an aircraft’s wings, the pectoral fins located on either side of the fish, helps it turn left or right and also provides support while swimming.

Finlets or Scutes
Finlets are small fins located between the dorsal fin and the tail of the fish or also between the anal fins and the tail of the fish. These finlets are found on fast swimming fish like tuna, and is said to aid in the speed of the fish, by cutting through the water.

© Aquaviews - SCUBA Blog, 2010. | Fish Identification Guide: Fish Anatomy (Part I) is an original article from Aquaviews.net | Be the first to comment!

Take our quiz to find out just how well your fish identification skills are. See how many fish you can name from the pictures below -

[QUIZZIN 2]

* Photo Credits: photos by M. Christian Selfridge, BlueBeyond, richard ling, alfonsator, loloieg, Boogies with Fish, TGIGreeny, glintle , doug.deep, PacificKlaus and Nataraj Metz on flickr

© Aquaviews - SCUBA Blog, 2010. | Can You Identify These Fish Species? is an original article from Aquaviews.net | Be the first to comment!

As the sun sets, and most of the reefs inhabitants make their way home for the night, there are groups of reef dwelling fish that are just beginning their day. Nocturnal fish make scuba diving at night a fascinating experience as these species of fish are mostly hidden during the day. These fish tend to have larger eyes, are more solitary, slow moving and are often reds or brown in color to make them indistinguishable as the light levels drop. Most nocturnal fish are carnivorous and predatory preying on other reef fish or invertebrates.  Here are some of the more commonly sighted creatures of the night you may spot in the glare of your dive light while reef diving.

Cardinalfish
With its brilliant red to light pink colors, the Cardinal fish can be easily found in shallow reefs of the Indo-Pacific at night. This fish has a large head and eyes, a comparatively smaller body and an angled mouth with a protruding lower jaw. The Cardinalfish ranges in size from between 2- 8 inches (5-20cms) in length and there are known to be around 200 species of this fish.

Big Eyes
Bigeyes are carnivorous nocturnal fish that hide by daylight and come out at night. Most bigeyes are bright red in color but can be found in paler shades as well and can grow to a length of about 41 cm (16 inches).  Bigeyes are found in almost all of the worlds the oceans in over 18 different species and are often found in large numbers hidden in shipwrecks or caverns during the day. Bigeyes have a peculiar way of swimming; they hang motionless in the water, in order to be able to observe the slightest movement around themselves. Then they suddenly dart forward, to intercept their prey.

Squirrelfish & Soldierfish
Squirrelfish & Soldierfish are perhaps one of the most easily recognized nocturnal reef fish. Known to have pinkish-red color as well as huge eyes these fish are almost completely nocturnal and remain hidden throughout the day. The squirrelfish and Soldierfish are members of the Holocentridae family of fish which comprise of around 80 species inhabiting most of the worlds oceans. Squirrelfish have a poisonous barb near their gills that can give painful stings if touched. Squirrelfish & Soldierfish are known to range in length from 5-50 cm or (6-20 in).

Porcupine Fish
One of the more common night diving sights are Porcupinefish, which like all boxfish, are endearing to look at and have large eyes and a rounded balloon-like body. These slow moving fish appear to swim very awkwardly in the water using their two fins located near their tails. While Porcupinefish are closely related to pufferfish, however porcupinefish have larger spines covering their body almost resembling a porcupine. Like pufferfish they too inflate to almost twice their normal size when threatened and possess a neurotoxin a thousand times more powerful than cyanide if eaten.  These fish are nocturnal, choosing to feed at night when their favorite food, mollusks are most active.

Scorpionfish
Scorpionfish are nocturnal hunters that are often difficult to spot owing to their excellent camouflage. This fish hunts by sitting still and waiting until a victim comes close to its mouth. Then it lunges forward, while opening its enormous mouth sucking the victim inside. The body of the Scorpionfish is covered by coarse scales and may contain spines which contain a powerful neurotoxin that is lethal to humans.

Snappers
Snappers can be either nocturnal or diurnal (daytime) fish depending on their species. With over 100 species of snapper, spotting a group of them on a night-dive is relatively easy. Several species of snapper feed on crustaceans and fish and hunt voraciously.

Moray Eels
Moray eels which tend to remain in the nooks and crevices during the day, with only their vicious heads poking out are more at ease at night, and tend to leave their hiding places to swim about scavenging on tiny fish and crustaceans. Perhaps one of the best opportunities for a scuba diver to see an eel’s true length is often on a night dive.

Octopus
While you can spot octopus on the reef during the daytime, at night several species become a lot more active and swim about the reef hunting their favorite invertebrates which also favor the darkness.

Invertebrates
Many invertebrates including lobsters, shrimp, crabs, and other crustaceans, mollusks, polychaete worms, and starfish scavenge the sea beds at night. Starfish especially which remain tucked away during the day seem to appear everywhere at night. Many shrimp migrate to the surface to feed on plankton, and the sea beds are often crawling with lobsters and crabs that brave the open areas under the cover of darkness.

photos from flickr by: doug.deep, jayhem, Nemo’s great uncle, alfonsator, Marcelo Mariozi – , Melissa Bowman & richard ling

© Aquaviews - SCUBA Blog, 2010. | Creatures That Go Bump In The Night is an original article from Aquaviews.net | Be the first to comment!

Australia is home to several unique plant and animal species that are found nowhere else in the world, and  the creatures inhabiting it’s oceans are no exception. Meet the Pineapple fish, one of the more unique fishes you will come across while scuba diving along the waters off  coastal Queensland, New South Wales, and Western Australia. Named owing to its stunning resemblance to a pineapple, this fish is also known as the knightfish or the coat-of-mail fish, due to the armor-like scales covering its body.

Pineapplefish grow up to 22 cm (8.7 in) long and are covered by several rough scales which are yellow in color and edged in black, adding to its pineapple-like appearance. Found exclusively in parts of  Australia, Scuba Divers have typically spotted this fish at around 5-20m and commonly found inhabiting rocky reefs and estuaries.

The most unique physical characteristic of the Pineapplefish apart from its uncanny resemblance to a

pineapple of-course, is that they possesses two tiny light or bioluminescent organs found on either side of the lower jaw that produces a greenish or reddish glow. These organs known as photophores, are a light-emitting organ which appears as luminous spots on various marine animals and are used to attract prey to the fishes mouth to feed on.  This unusual feature has also given the Pineapplefish another name to be known by, since its light organs resemble navigation lights on ships: the port-and-starboard light fish. The light in the photopore is produced by bioluminescent bacteria which emit a green glow when the fish is young and becomes a reddish glow as the fish ages. Being nocturnal fish, the Pineapplefish uses its photophres to lure in its favorite prey of small shrimp to its mouth at night which is a useful feature owing to the fact that these fish have small fins and are not very good swimmers.

Pineapplefish are often found in small caves and under ledges where they aggregate in small groups and Divers have found the certain groups of pineapplefish inhabiting the same ledge for several years at a time often upto 7 years. There are several locations along the New South Wales coast that divers can visit and regularly find Pineapplefish hanging out in the same location making the job of searching for these unique fish by underwater photographers and scuba divers relatively easy.

photos from flickr by richard ling, Saspotato,

© Aquaviews - SCUBA Blog, 2010. | Meet the Pineapplefish is an original article from Aquaviews.net | Be the first to comment!

The Whitemargin Unicornfish is truly a fascinating Reef Fish which is a delight to sight while scuba diving in the waters of the Indo-Pacific. These fish are known as Unicornfish because of a spike/horn that protrudes from its forehead which can grow quite prominently which makes this fish easy to identify and a curious inhabitant of the reef. The “Whitemargin” part of its name comes from the tail of the fish which is black surrounded by a white margin.

Whitemargin Unicornfish  or Naso annulatus belong to the Tang or  Surgeonfish  family known as Annulatus. The distinctive characteristic of the Annulatus or surgeonfish family is the spines, one or more on either side of the tail, which are dangerously sharp.  The Whitemargin comes from the “Naso” genus of the Annulatus family which comprise of 17 species of tropical marine surgeonfish’s  all having some form of horn or protrusion from their foreheads. The word Naso in Latin means nose.

The Whitemargin unicornfish is found throughout the Indo-Pacific, commonly found in coral reefs, and rocky tropical areas of the Indian and Pacific Oceans and the Red Sea. Some are also said to be found near Hawaii and Japan. This species lives in the reefs at the depth range of  1 – 60 m i.e. up to 197 feet.

The Whitemargin can reach a length of 100 cm (3.3 ft) making it one of the largest members of the Surgeonfish family and a delight to divers, especially underwater photographers who spot an adult specimen on their dive.

These fish are mainly active in daytime and roam in groups feeding on algae. Being pure herbivores, their favorite food comprises of Leafy brown algae such as sargassum.

The horn-like appendage between their eyes begins growing when a young fish reaches about 13 cm (5 in) in length, and tends to be a little bigger on males. The fish never use this horn as a weapon or even for self-defense but instead use their sharp scalpel-like spines by their tails as a weapon.

photos from flickr by Zanthia, JoshBerglund19, Oriolus

© Aquaviews - SCUBA Blog, 2010. | Fish Identification: The Whitemargin Unicornfish is an original article from Aquaviews.net | Be the first to comment!

Finding Nemo

The 2003 Pixar CGI animated Film “Finding Nemo” was so popular when it first released, that even today most people look at the clownfish in an aquarium and identify  it as ‘Nemo ‘ and not as a Clownfish. At first people thought the phenomenon would pass, and the interest generated by the movie would fade away. However even today most Scuba diving instructors will tell you that their new students still recognize reef fish by their Nemo Names, and phrases like: “I saw two Dory’s and a whole bunch of Gills”, or “Did you see Nemo in that anemone?”, are not uncommon. So we at Aquaviews decided to help our Nemo crazed fans, find Nemo and his friends.

Nemo and Marlin: False Ocellaris Clown fish

False Ocellaris Clown fish are closely related to the true clownfish better known as the orange clown fish and are both species that are found in coral reefs of the Indo-Pacific. The Ocellaris can be recognized by its orange color with three white bars and black markings on the fins and you will almost always find them living in the protection of an anemone.

Dory : Regal Blue Tang

The Regal Blue Tang comes from the family of surgeon fish and can be identified by its royal blue body, yellow tail, and black ‘palette’ design. This species is relatively common in the reefs of the Indo-Pacific and lives of plankton. Tangs can grow up to a foot in length and due to their stunning color, are a real delight to spot while diving in a reef.

Tad : Tad Yellow Longnose Butterflyfish

The yellow long nose butterfly fish is one of the most common kinds of butterfly fish and is instantly recognized by its bright yellow body and tapering short black nose. The Yellow Longnose Butterflyfish inhabits the Indo-Pacific and Eastern Pacific and any scuba diver who has dived in Hawaii will instantly recognize this fish.  They commonly found on exposed seaward reefs and not very common in lagoon reefs.

Gill : Moorish Idol

Another really popular character from the Movie, Gill is a Moorish idol which is often mistakenly identified as a butterflyfish, Angelfish, bannerfish or pennant fish which appear in similar colors. The Pennant Coral fish closely resembles the Moorish idol, which can be distinguished from the pennant by the black band that goes over its eye and its distinctive tubular snout that sets it apart. The Moorish Idol however belongs to the Surgeonfish family and grows to a length of 8-10 inches.

Bloat : Puffer Fish

Pufferfish are by far one of the most extraordinary fish of the reef. When stressed pufferfish can puff up to 2 or 3 times their normal size. They are slow swimming fish, and swim rather awkwardly in the water. There are also several kinds of pufferfish, like boxfish, cowfish, porcupine, burrfish, stars and stripes puffer, the dog faced puffer, the figure eight puffer, etc. Bloat in Finding Nemo is a Porcupine Pufferfish recognizable by its yellow color and long spines which sticks out when it inflates.

© Aquaviews - SCUBA Blog, 2009. | Finding Nemo and His Friends is an original article from Aquaviews.net | Be the first to comment!