Post by sam on Dec 27, 2008 17:59:51 GMT -5
THE LATERAL LINE:
Fish have a unique sense of touch. The LATERAL LINE, a row of tiny holes that runs along each side of the body. Sensitive hairs inside each hole detect the location and direction of movement as in the diagram (5) below:
Source: www.amonline.net.au/fishes/fishfacts/fish/fishfig.htm
Vision, hearing and equilibrium are all senses that are familiar to us because of our own experience with them. The lateral line system, however, is only found in fishes and the aquatic stages of amphibians. Perhaps the most descriptive term for this system is the German word Ferntastinn, which means “distant touch.” The lateral line system responds to any type of water movement, including disturbances, currents and even the movements of other fishes.
The sensory receptors of the lateral line are called neuromast organs, which are similar to our inner ears. It consists of a number of sensory hair cells enclosed in a cupula similar to the cells that give us our equilibrium. In fishes these receptors are come in two types, 1) epidermal organs, which are in the skin, and 2) canal organs, which are in a system of canals beneath the skin.
The lateral line is critical to the fish’s survival because in most cases a Fish’s visual field is much smaller than the visual field of terrestrial animals. For example, in muddy water the fish uses it’s lateral line system to detect movements in the water to find its prey or to avoid predators such as a largemouth bass. That’s why bass hit spinner baits in muddy water - they feel the vibration of the blades. Studies have shown blind fishes can still strike baits and find their way around using their lateral line. The lateral line also appears to play an important part in the schooling behavior of some fishes.
It’s how they are able to school and move in such a coordinated manner when threatened.
A final note is on how fishes differentiate the “noises” they receive while using their lateral line. A fish such as a trout in a North Georgia stream are attuned to the normal “noise” of the current and the other fishes in the pool.
When food crashes to the surface or when someone like JOE FISHERMAN comes tromping up stream the fish knows something different is occurring in the environment around it. That’s when it takes action to feed or to protect itself. It’s almost like how people filter out conversations at a large party; they focus on what they’re interested in. For the trout it’s food and survival.
The lateral-line system, which detects low-frequency (<100 Hz) particle motion in the water contacting the flanks of the fish, and the inner ear, located within the head of the fish, sensitive to frequencies of up to 1-3 kHz. The lateral line organ is almost certainly involved in acoustic repulsion when the sound source is at close quarters (within a few body lengths of the fish) but the inner ear is thought to be the main sensory organ involved.
HOW FISH FIND YOUR BAIT:
Fish usually detect your bait by sound and water movement. They hear and "feel" their way to your lure with their ears and lateral lines. Once they see the lure, they can tell if it looks like something they usually eat. Then the fish might smell or taste the lure before inhaling it. As the fish inhales the lure for the final taste test, you're likely to feel a tug on the line. That's when you must set the hook quickly, before the fish spits out the lure.
Timing can be the difference between going home with a fish or a story about fish and the fish that got away.
Fish have a unique sense of touch. The LATERAL LINE, a row of tiny holes that runs along each side of the body. Sensitive hairs inside each hole detect the location and direction of movement as in the diagram (5) below:
Source: www.amonline.net.au/fishes/fishfacts/fish/fishfig.htm
Vision, hearing and equilibrium are all senses that are familiar to us because of our own experience with them. The lateral line system, however, is only found in fishes and the aquatic stages of amphibians. Perhaps the most descriptive term for this system is the German word Ferntastinn, which means “distant touch.” The lateral line system responds to any type of water movement, including disturbances, currents and even the movements of other fishes.
The sensory receptors of the lateral line are called neuromast organs, which are similar to our inner ears. It consists of a number of sensory hair cells enclosed in a cupula similar to the cells that give us our equilibrium. In fishes these receptors are come in two types, 1) epidermal organs, which are in the skin, and 2) canal organs, which are in a system of canals beneath the skin.
The lateral line is critical to the fish’s survival because in most cases a Fish’s visual field is much smaller than the visual field of terrestrial animals. For example, in muddy water the fish uses it’s lateral line system to detect movements in the water to find its prey or to avoid predators such as a largemouth bass. That’s why bass hit spinner baits in muddy water - they feel the vibration of the blades. Studies have shown blind fishes can still strike baits and find their way around using their lateral line. The lateral line also appears to play an important part in the schooling behavior of some fishes.
It’s how they are able to school and move in such a coordinated manner when threatened.
A final note is on how fishes differentiate the “noises” they receive while using their lateral line. A fish such as a trout in a North Georgia stream are attuned to the normal “noise” of the current and the other fishes in the pool.
When food crashes to the surface or when someone like JOE FISHERMAN comes tromping up stream the fish knows something different is occurring in the environment around it. That’s when it takes action to feed or to protect itself. It’s almost like how people filter out conversations at a large party; they focus on what they’re interested in. For the trout it’s food and survival.
The lateral-line system, which detects low-frequency (<100 Hz) particle motion in the water contacting the flanks of the fish, and the inner ear, located within the head of the fish, sensitive to frequencies of up to 1-3 kHz. The lateral line organ is almost certainly involved in acoustic repulsion when the sound source is at close quarters (within a few body lengths of the fish) but the inner ear is thought to be the main sensory organ involved.
HOW FISH FIND YOUR BAIT:
Fish usually detect your bait by sound and water movement. They hear and "feel" their way to your lure with their ears and lateral lines. Once they see the lure, they can tell if it looks like something they usually eat. Then the fish might smell or taste the lure before inhaling it. As the fish inhales the lure for the final taste test, you're likely to feel a tug on the line. That's when you must set the hook quickly, before the fish spits out the lure.
Timing can be the difference between going home with a fish or a story about fish and the fish that got away.