- 1 How can you tell how old a fish is by scale?
- 2 What are the two ways that allow us to determine the age of the fish?
- 3 How can you tell a fish’s gender?
- 4 What is the oldest class of fish?
- 5 Which is the most poisonous fish in the world?
- 6 Why do we age fish?
- 7 What is a female fish called?
- 8 Are my fish fighting or mating?
- 9 How long is a fish pregnant?
- 10 What are the 3 major classes of fish?
- 11 What separates sharks from other fish?
How can you tell how old a fish is by scale?
Scales are the most widely used aging structure in North America because of their non-lethal ease of collection. Counting the number of annuli (rings) on a scale provides the fish age and the spacing between rings is proportional to the growth of the fish.
What are the two ways that allow us to determine the age of the fish?
The two primary ways to age fish is to either examine scales from the fish or to examine one of the otolith’s (inner ear bones). During times of slow growth, such as in winter for warm water fish, the layers of growth in these structures are closer together and form a dark line (annuli, for annual rings).
How can you tell a fish’s gender?
Males are usually smaller and more colorful than females. They also possess an external sexual organ, the gonopodium, which makes it easy to differentiate males from the females: In the male, the anal fin is rod-shaped, while the female has a traditional fan-shaped anal fin.
What is the oldest class of fish?
The oldest class of fish, the Superclass Agnatha, includes lampreys and hagfish. Unlike the agnathans, the fish in the chondrichthyes class have jaws made of cartilage; these fish include sharks, rays, and chimaeras.
Which is the most poisonous fish in the world?
The most venomous known fish is the reef stonefish. It is an ambush predator which waits camouflaged on the bottom. The beautiful and highly visible lionfish uses venomous barbs around its body as a defence against predators.
Why do we age fish?
Just like aging a great piece of beef, aging fish helps intensify the flavor and improve the texture of the meat. The enzymes also help to break down connective tissues, leaving fish more tender and with palatable profiles.” PABU. Like most living things, fish go through rigor mortis following death.
What is a female fish called?
What is a female fish called? A female fish does not have a specific name, male and female fish are both just called fish. However, around 500 species of fish are able to change their gender during their later life after birth. A species of fish that can change its gender is called a hermaphrodite.
Are my fish fighting or mating?
If they are fighting, a fish that feels threatened is more likely to cower in a corner, not dive into the situation head on. They’re basically trying to protect their breeding ground, and a fish of the same species and sex is competition.
How long is a fish pregnant?
As examples, the female swordtail and guppy will both give birth to anywhere from 20 to 100 live young after a gestation period of four to six weeks, and mollies will produce a brood of 20 to 60 live young after a gestation of six to 10 weeks.
What are the 3 major classes of fish?
Fishes are typically divided into three groups: superclass Agnatha (jawless fishes), class Chondrichthyes (cartilaginous fishes), and superclass Osteichthyes (bony fishes). The latter two groups are included within the infraphylum Gnathostomata, a category containing all jawed vertebrates.
What separates sharks from other fish?
But how is a shark different from other kinds of fish? Most other fish have skeletons made of bone. A shark’s skeleton is made of cartilage, a type of strong but flexible tissue. Most other fish are covered in smooth, flat scales.