Fussy Ways of the Captive Paddlefish
The captive paddlefish will pay no attention to the ground meat unless it is suspended in the water-it never takes food off the bottom.
The movements of the school of hickory shad agitate the water and keep the fine particles of meat in suspension, simulating a cloud of plankton organisms.
But ground muscle meat does not contain the essential vitamins, oils, minerals and proteins synthesized in plankton under the bright life-stimulating sun and this may account for the condition of Chute's ailing spoonbill.
The function of the paddlefish's huge nasal adornment has been the subject of much debate.
That now famous proboscis is definitely not an offensive weapon like the superficially similar, but really quite different, unyielding, armor-piercing bony sword of Xiphias gladius, the swift, torpedo-like swordfish.
The paddlefish's bill is stiffish but not rigid, and it may be broken easily.
Spoonbills have often been known to pass through the churning turbines of hydroelectric plants.
Many emerge in fairly good condition, except for injured beaks.
Some fish seem to get along without their nasal staff-others appear to be bewildered and swim aimlessly about.
Some naturalists claim that the paddlefish's paddle is used to stir up the mud and drive the tiny, aquatic, burrowing, insect larvae and other organisms out of their hiding places, so that they may be swept into its huge gaping jaws.
Many drawings and paintings of the paddlefish show the fish in the act of stirring the bottom ooze.
Some naturalists have gone to the other extreme and have questioned the value of Polyodon's elongated snout, saying that it has little, if any, use in straining the microscopic food from the water-a job done by the gill arches.
Dr.
C.
A.
Kofoid, who calls Polyodon "a living plankton net," discovered the fact that the fish's paddle-shaped snout is highly sensory and this fact alone furnishes the key to another one of many riddles wrapped in the life of the fish.
The paddlefish uses its long, extended snout primarily to detect the presence of its food.
When the American Society of Ichthyologists and Herpetologists met in Chicago not long ago, the Shedd Aquarium director put on a special Polyodon show for the members.
As the visitors crowded about the tank where the paddlefish was lazily cruising about - one of Director Chute's men quietly poured a bucketful of concentrated daphnia into the water.
It was noticeable that just as the cloud of daphnia sank to the level of the spoonbill's paddle, it seemed suddenly to become extremely excited.
Its lower jaw dropped like a trap door, opening its huge net-like mouth.
With its jaw6 gaping widely, it cruised about swinging its sensitive snout to the right and left as if seeking to detect and then to engulf the greatest number of daphnia in the tank in the shortest possible time.
As another pailful of waterfleas was spilled into the aquarium, the entire performance was repeated.
The movements of the school of hickory shad agitate the water and keep the fine particles of meat in suspension, simulating a cloud of plankton organisms.
But ground muscle meat does not contain the essential vitamins, oils, minerals and proteins synthesized in plankton under the bright life-stimulating sun and this may account for the condition of Chute's ailing spoonbill.
The function of the paddlefish's huge nasal adornment has been the subject of much debate.
That now famous proboscis is definitely not an offensive weapon like the superficially similar, but really quite different, unyielding, armor-piercing bony sword of Xiphias gladius, the swift, torpedo-like swordfish.
The paddlefish's bill is stiffish but not rigid, and it may be broken easily.
Spoonbills have often been known to pass through the churning turbines of hydroelectric plants.
Many emerge in fairly good condition, except for injured beaks.
Some fish seem to get along without their nasal staff-others appear to be bewildered and swim aimlessly about.
Some naturalists claim that the paddlefish's paddle is used to stir up the mud and drive the tiny, aquatic, burrowing, insect larvae and other organisms out of their hiding places, so that they may be swept into its huge gaping jaws.
Many drawings and paintings of the paddlefish show the fish in the act of stirring the bottom ooze.
Some naturalists have gone to the other extreme and have questioned the value of Polyodon's elongated snout, saying that it has little, if any, use in straining the microscopic food from the water-a job done by the gill arches.
Dr.
C.
A.
Kofoid, who calls Polyodon "a living plankton net," discovered the fact that the fish's paddle-shaped snout is highly sensory and this fact alone furnishes the key to another one of many riddles wrapped in the life of the fish.
The paddlefish uses its long, extended snout primarily to detect the presence of its food.
When the American Society of Ichthyologists and Herpetologists met in Chicago not long ago, the Shedd Aquarium director put on a special Polyodon show for the members.
As the visitors crowded about the tank where the paddlefish was lazily cruising about - one of Director Chute's men quietly poured a bucketful of concentrated daphnia into the water.
It was noticeable that just as the cloud of daphnia sank to the level of the spoonbill's paddle, it seemed suddenly to become extremely excited.
Its lower jaw dropped like a trap door, opening its huge net-like mouth.
With its jaw6 gaping widely, it cruised about swinging its sensitive snout to the right and left as if seeking to detect and then to engulf the greatest number of daphnia in the tank in the shortest possible time.
As another pailful of waterfleas was spilled into the aquarium, the entire performance was repeated.
