Diving Into Perch

Objectives

1) Work with a lab group to learn from the dissection of a perch

2) Observe the placement of organs and their relationships to one another

Background Information

Scientific Name: Perca

Habitat: Small ponds, lakes, streams, rivers

Predators: larger fish, birds, herons, eagles, turtles

Prey: live insects, crustaceans, small fish

Adaptations: large eyes to aid in feeding; spines for protection; stiffness in fins and a thin shortened disc-shaped body so it's harder for a predator to swallow

Dissection!

Live Dissection:

Bony Fish (Perch) Anatomy

Cladogram:

System Focus:

Swim Through the Circulatory System

The circulatory system of a fish is similar to that of many mammals, it consists of a heart, blood, and blood vessels. What is unique about a Perch's circulatory system is that it is a single circle circulation that is considerably low pressure. You can think of the system going through three easy steps.

1. Oxygen deprived blood goes to the heart to then be pumped through the gills.

2. In the gills, it gathers oxygen molecules, to where it is pumped through the body and its tissues.

3. The now deoxygenized blood circulates back to the heart to start the process over again.

In fish, before the deoxygenized blood reaches the heart, it is carried by the veins into a cavity called the Sinus Venosus.

Cross Content:

Human Impact

Perch are common around the world, and due to that it is one of the most common fish on human's plates. Thousands of perch are subject to death by boiling, deep frying, grilling, breading, etc. each year. Perch are also used as show fish in the aquarium.

In the case of the Nile river perch, humans are having a positive effect on the overwhelming perch population there. The perch eggs hatch in the millions in just 20 hours, and they're inhibiting too much of the water, not allowing for equilibrium in the biome. African fishers weeding out some of the perch is moving the Nile back towards it's normal standing.

Taxonomy

The taxonomic name "perca" is actually an early Greek name for perch. Though the ones we dissected were discolored a bit, the common name in latin (flavescens) comes from it's yellowish coloration. Other common names for the perch include: American Perch, Bandit Fish, and Calico Bass.

Evolution

Dr Frans Witte from Integrative Zoology has discovered this type of fish in Lake Victoria, Africa to have evolved and adapted extremely fast to changing circumstances. The gills seem to have increased in size since the 1970's, which allows their respiratory systems to function more effectively.

Interesting Information

  • the meat of this species is low in fats and rich in phosphorous, manganese, selenium and vitamin B12
  • Perch spawn at the temperature of about (43 to 48) degree Fahrenheit
  • Perch are found in Britain, Europe, South Africa, Asia and Australia

Punderful Perch Jokes

What did the fish say after swimming into a concrete wall?

Dam.


Where do fish keep their money?

In the river bank.


What's the difference between between a fish and a piano?

You can't tuna fish.

Bibliography

By

Maya Waterland

Guzman - PAP Bio - 7