Into the Perch

Objective: to observe external and internal parts of a perch

By Olivia Helm Guzman- 4th

Dissecting the life of a Perch

The common perch is found in the Perca genus. The perch to the right is called the yellow perch but is scientifically called the Perca flavescens. The perch is a carnivorous fish that feeds on smaller fish, shellfish, and bug larvae in many different places. Generally they are found in small lakes, rivers, and streams all over the world. Depending on the place, the perch is fed upon by birds, larger fish, and in some cases turtles. In some places humans are considered predators of the perch that need to back off; a few years ago there was lots of discussions over the overfishing of the yellow perch in Lake Eerie and the other Great Lakes as well. The link below has one person's opinion on the matter of this abused human impact on the lives of the perch. Another perch, the Nile Perch, faces the same problem of overfishing in Lake Victoria, in Africa.

Deeper into the circulatory system.

Like humans, the perch has a closed circulatory system. However, unlike humans, the heart of a perch has only two chambers; it has an irregular shape that consists of only one ventricle and one atrium. Because of this its system is considered a low pressure, single loop system. The deoxygenated blood inside the body collects in the atrium and then passes to the ventricle through a valve. When the ventricle then contracts it forces the blood to the gills so that it can be oxygenated. After being oxygenated it is sent back through the body. When it then becomes deoxygenated it collects again in the atrium and the cycle repeats.

The circulatory system has a very important role in the perch and in all animals. This system carries around the oxygen that living things need to live. This system also works with the digestive system. When the nutrients are broken down by the intestines, they are then put into the bloodstream so that they can be carried all over the body.

The video below allows one to see both some of the major arteries and the two distinct parts of the heart of a perch.

Fish Circulatory System

Adaptations and Fun Facts

Adaptations:

The perch has evolved to be darker in color and have stripes in order to hide in the weeds and plants that are found in their habitat.

The perch also has a light colored belly to make it less visible to predators below it.

Fun Facts:

There are many different types of perch that have varying characteristics when it comes to size and color but their sleek shape remains about the same.

The females usually spawn sometime in the spring.

Perch in the Perca genus usually grow to be about 5 pounds maximum but other species can grow up to be more than 200 pounds (The Nile Perch video link below)

Diversity in the Perch Family

This will direct you to a video that shows a relative of the common perch called the Nile Perch. It's much larger than the one that we dissected but all the same is still considered a perch.