Angelfish: A Behavioral Study Within Two Tanks

Angelfish: A Behavioral Study Within Two Tanks By Julie Barker

Pterophyllum Scalare or Angelfish • Originally found in the Amazon region of South America • Pterophyllum is derived from Greek meaning “winged leaf” • Scalare is translated as, “like a flight of stairs,” or ‘latter” in Latin and is a quality that is reflected in the dorsal fin.

Qualities of the Angelfish • Angelfish are more disc-like in structure, they are long and narrow but slender on the sides • Have two fanned fins on both the top and bottom of their bodies • There are two feelers that lie in front of this bottom fin • Depending on the variety, the tail may differ in shape, yet is always oriented vertically.

Silver Zebra Black lace Black Half Black Veil tail Marble Golden Gold marble Pearly Golden Blushing Pearl Scale Blue blushing Koie Other lesser common varieities Varieties of Angelfish

Silver Angelfish • Most common variety in wild • Displays 4 dark vertical bars running along its sides • First bar runs through the eye • Second is located in front of the top and bottom fin • Third is at the back of these fins • Last will run through the tailfin • Body is silver in color and the head can be brownish in color • Stripes may break, be less pronounced than others and some may not even be solid

Zebra Angelfish • Like Silver, but with more stripes • Stripes extend through the tailfin • Can have a black body with alternating small zebra stripes • May also be a hint of glittering gold at the top of the body

Black Lace Variety • Black body with black fins • Body features dark and light black stripes • Black lace is also like the silver variety, yet contains an intense color • Color difference is most noted in the fins where a lace pattern appears. • Co-dominant genes produce produce 25% black, 50% black lace and 25% silver when interbred

Black and Half Black • Black angelfish are solid velvety black, there are no streaks within its coloring • Half black varieties are half black or dark gray on the rear of the body and silver in the front of the body , segmentation occurs through the upper and lower fins as well as the body

Veil Tail Angelfish • Have elongated fins and may come in every color

Marble Angelfish • Marble angelfish have an array of broken black and silver. The head may have golden coloration and the fins may contain rays of black and white

Golden Angelfish • May have the coloration anywhere from solid silvery white to a golden color with no other markings • head and back usually contain a mantle of gold • Often have a shiny pale yellow body • not born with its coloration, yet as the fish ages, the color will appear. • At a young age, this variety is often misidentified as a blushing or koie

Gold marble Angelfish Gold marble angelfish are like the golden variety yet there are black streaks on the body and/or fins

Pearly Gold Angelfish • Contain a base color of pearlesque gold • Have a rough, aluminum foil like body • Coloration reflects light revealing a wondrous display of light and color

Blushing Angelfish • Have a red cheek area with no other distinctions on their body • rest of the body is colorless, or white • some display gold appearance on the head • reported to be the most delicate • When young, display a red coloration under the eyes • coloration is actually the appearance of their red gills that disappears with age

Pearl Scale Angelfish • Have bumpy, rougher scales • May come in several colors

Blue blushing Angelfish • Gray and usually contain a black trim • Can see red under the eyes, as in the blushing variety, and is less pronounced as the angelfish matures • As the fish’s mood changes, the body and fins display a very light color.

Koie Angelfish • White with black patches • Can contain golden on the head area • May display the red coloration of the blushing variety that will fade with growth

Parallel Symmetry • Angelfish tend to stay parallel to each other’s bodies • When one fish turns, then the other fish will realign itself to the same parallel direction • Both of the heads are faced the same way, or a tail is faced the same way on one fish as the head of the other fish.

Observed In My Tank • In tank A, where one angelfish is larger than the other, it is noticeable that the smaller fish will align its body to the direction of the larger fish

Reasons For Parallel Swimming • May be a defensive gesture • Angelfish have eyes on the sides of their heads and may not see predators approaching from the sides • If their slender bodies are facing the same direction, predators may appear smaller in size • If the predator approaches from sides then the angelfish would retreat showing its small tail

Intuition or Learned Behavior? • Seems to occur in 4 week old angelfish

Curiosity • Interest with regard to food • Human the marble angelfish in Tank A always peeks out at the human, as if to beg for attention • When a finger is placed outside of the glass of the tank blushing angelfish will first approach the object and follow the finger

Larger Fish Dominance • If larger marble angelfish approaches, the smaller blushing angelfish will move to a distance of a few inches from the marble angelfish • Marble angelfish then continues the behavior of the blushing angelfish • blushing angelfish is always by the marble angelfish at a parallel

Feeding Controlling Behavior • When food is introduced to the tank, the angelfish are the first genus to know that food is coming to them and be waiting as soon as the lid is raised • Once feeding has taken place, the angelfish no longer exhibit a response to an object outside of the tank • When a few hours have passed, the response is once yet noted.

Blushing: A Shy Guy? • Blushing angelfish are known to be the most delicate • Blushing angelfish in Tank A is highly aggressive towards the food source unlike larger marble • When large pellets of food are introduced to the tank, the blushing angelfish attempts to eat them even though its mouth is too small to grab the pellets

Does Size Really Matter? • The blushing angelfish will eat much more quickly than the marble fully grown angelfish • Is this due to the fact that the blushing is still growing? • In Tank B, both a golden angelfish and the sliver angelfish are of the same size as the blushing angelfish in Tank A and demonstrate the same feeding behavior as the blushing angelfish.

Curious Lip Locking Behavior:Is It Love? • Behavior arises spontaneously • Begins when the two angelfish lock lips, almost looking like they were being very intimate • As the behavior continues, it is notable that this is not an affectionate locking of the jaws, but is one of aggression

And In Corner One:The Fish Fighting Stance • Once they lock jaws, they push as hard as they can towards each other • Typically take intermediate breaths and rest • After locking jaws many times and returning to get oxygen, the silver angelfish retracts its feelers and then bounces them down in display of dominance

Pecking Orders • Silver angelfish then begins to peck around the bottom of the gills, underneath the mouth on the golden angelfish • Reoccurs several times. • The golden angelfish begins to raise its mouth anticipating the pecks from underneath • The silver then swims two circles around the golden angelfish • Pecking then continues on the golden angelfish. Both fish return to the surface for air before the silver then circles the golden angelfish twice more • Pecks then are repositioned to the golden angelfish’s head • Golden angelfish anticipates this peck and “bows down” to the silver angelfish before the peck is given

Dominance of Territory • The silver then pecks on the side behind the eye • Golden angelfish retracts and swims away • Silver angelfish then follows in parallel • Continue in opposite directions • Silver then sneaks upon the golden angelfish and begins to peck it on the tailfin • Silver pecks • Gold retracts • Probably due to dominance

Angelfish: A Behavioral Study Within Two Tanks