Handbook of Nature-Study · Lesson XXXVIII · Topic 3: Fish study
38. The common sucker
Goal: Your child can describe how the sucker's shape, colors, eyes and downward-facing mouth suit it for feeding on the bottom.
You'll need
- A clear stream, river edge or lake shore with still pools
- Polarized sunglasses
- A bridge or dock to look down from (with an adult)
- Nature notebook
What's in the book
The leading thought, the method (study the sucker in its native pools first, then in the aquarium) and seven questions about where suckers live and what they eat, shape and colors, fins and scales, eyes, nostrils, the mouth on the underside, and their spring runs and habits.
The lesson, step by step
When and where
Early spring is best, when suckers crowd up streams to spawn and can be seen from bridges and banks. In summer, look in still, clear pools along rivers and lakes. Comstock says it is far more interesting to see a sucker where it lives before any aquarium study. Safety: an adult stays within arm's reach near any water. Stay off steep or slippery banks and never wade in fast water.
Keep the big idea in mind
Read this to yourself:
The sucker is especially adapted by shape for lying on the bottom of ponds under still water where its food is abundant.
Find them
Look down into clear water with polarized sunglasses. Suckers look like long, dark logs resting on the bottom.
What do suckers look like on the bottom of the pond? Are they easily seen?
What is the color above? On the sides? Below?
Shape
What is the shape of this fish's body when seen from above? From the side?
Compare with the bullhead from Lesson XXXVII.
The mouth
Where is the mouth of the sucker situated? What is its form? How is it adapted to get the food which the sucker likes best?
It is on the underside of the head, with thick lips, like a vacuum cleaner for the bottom.
Eyes
Describe the eyes; how are they especially adapted in position and in movement to the needs of a fish that lives on the bottom of streams and ponds?
Put it into words
Ask your child how a sucker is made for life on the bottom. Then share the leading thought.
Nature notebook
Draw a sucker on the stream bottom, seen from the side, with the mouth underneath. Add a small view from above.
Afterwards
Comstock asks: "When do you see them first in the spring? Where do they go to spawn?" Check a stream bridge every few days in early spring.
Tip
If you catch a fish to look at, use a small net, keep it in a clear container of water from the same stream, in the shade, for no more than 10 to 15 minutes, then let it go exactly where you caught it. Wet your hands before touching a fish, or better, don't touch it at all. Check your state's rules first; some places need a fishing license even to net small fish.