Handbook of Nature-Study · Lesson XXXVII · Topic 3: Fish study
37. The bullhead, or horned pout
Goal: Your child can explain how the bullhead's whiskers (barbels), flat shape and spines suit it for life on muddy bottoms.
You'll need
- A pond, slow stream or public aquarium where bullheads or other catfish can be seen
- Polarized sunglasses help you see into water
- A clear container and small net (optional)
- Nature notebook
What's in the book
The leading thought, the method (a small bullhead in a jar, first in clear water, then with mud and gravel added) and fifteen questions about its barbels, food, mouth, shape and color, eyes, fins including the small fleshy back fin, its spines, fishing for it, and its nest and care of the young. A humorous passage about the catfish as the boy's fish follows.
The lesson, step by step
When and where
Late spring and summer, when bullheads are active in warm, muddy ponds and slow streams, often near docks. A public aquarium, nature center or a friend who fishes can also show you one. 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 bullhead lives in mud bottoms of streams and ponds and is particularly adapted for life in such locations.
Comstock kept a small bullhead in a jar. Comstock herself set the rule for fish brought in from a brook: "The practice should be established, once for all, of putting these finny prisoners back into the brook after they have been studied."
Whiskers
What at the first glance distinguishes the bullhead from other fish? Describe these strange "whiskers" growing about the mouth; how many are there and where are they situated?
Where do we find bullheads? On what do they feed? Would their eyes help them to find their food in the mud? How do they find it?
Body shape
What is the general shape of the body? What is its color? Has it any scales?
Why should the bullhead be so flat horizontally while the sunfish is so flat in the opposite direction?
Compare: the bullhead is flat on the bottom like a pancake; the sunfish is flat side to side like a coin standing up.
Spines: look, don't touch
How does the bullhead inflict wounds when it is handled? Tell how these spines protect it from its natural enemies.
The sharp spine at the front of the back fin and of each side fin can give a painful jab. Only an adult who knows how should hold one.
The extra fin
Describe the dorsal fin, giving its comparative size and position. Do you see another dorsal fin? Where is this peculiar fin and how does it differ from the others?
It is a small, soft, fleshy fin near the tail, called the adipose fin. Trout have one too (Lesson XL).
Put it into words
Ask your child how a bullhead finds food in dark, muddy water. Then share the leading thought.
Nature notebook
Draw a bullhead from the side, whiskers and all, and label the barbels, the spines and the little fleshy fin. If you caught one, add the date and place, and that you let it go.
Afterwards
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.
Tip
Comstock asks children to write about how bullheads build nests and guard their young. Both parents guard the cloud of tiny black young; look for a dark swarm near the shore in early summer.