THE MUSKRAT
■ Type: Mammal
■ Diet: Herbivore
■ Average life span in the wild: 3 to 4 years
■ Size: 55-64 cm (22-25 in)
■ Weight: 1.8 kg (4 lb)
■ Muskrat Biology:
■ Diet: Herbivore
■ Average life span in the wild: 3 to 4 years
■ Size: 55-64 cm (22-25 in)
■ Weight: 1.8 kg (4 lb)
■ Muskrat Biology:
The muskrat, together with the beaver and several other mammals, is capable of remaining submerged up to 15 minutes if in a relaxed state. Non-aquatic mammals cannot do this because they need a constant supply of oxygen and must continually expel carbon dioxide. The muskrat is able to partially overcome this problem by reducing its heart rate and relaxing its muscles when submerged; this reduces the rate at which oxygen is used. Also, it stores a supply of oxygen in its muscles for use during a dive and is less sensitive to high carbon dioxide levels in the blood than are non-diving mammals. This ability for extended dives is important in escaping enemies, digging channels and burrows, cutting submerged stems and roots, and travelling long distances under the ice.
The muskrat’s front teeth are especially modified for underwater chewing. Non-aquatic mammals such as dogs or humans would have great difficulty in trying to chew on a large object under water, because water would enter the mouth, throat, and nasal passages. This problem has been overcome in the muskrat through the evolution of incisors, or cutting teeth, that protrude ahead of the cheeks and of lips that can close behind the teeth. This adaptation permits the muskrat (and the beaver) to chew on stems and roots under water "with its mouth closed."
Of all plants available in marshes, cattails are most preferred as a food item. However, muskrats appear to thrive equally well on a diet of bulrushes, horsetails, or pondweeds, the last two constituting the basis of the diet in northern latitudes. They also eat a variety of other plants, including sedges, wild rice, and willows.
During the winter a thick layer of ice restricts the muskrat to the interior of the lodge or burrow and the watery environment beneath the ice. The animal’s highly developed diving abilities and its use of push-ups become critical in procuring food under those conditions. It covers considerable distances under the ice searching for food. When the muskrat reaches a feeding area it chews off portions of plants and carries them to the nearest push-up, where it eats. This foraging activity under perhaps a metre of ice and snow, in ice-cold water and almost total darkness, is truly a remarkable feat.
When their normal food items are scarce or unavailable, and food of animal origin is abundant, muskrats are known to be highly carnivorous, or meat-eating. Under these circumstances muskrats most commonly consume animals such as fish, frogs, and clams. However, muskrats rarely do well on this type of diet and consuming such foods is generally taken to be evidence of hard times.
The muskrat’s front teeth are especially modified for underwater chewing. Non-aquatic mammals such as dogs or humans would have great difficulty in trying to chew on a large object under water, because water would enter the mouth, throat, and nasal passages. This problem has been overcome in the muskrat through the evolution of incisors, or cutting teeth, that protrude ahead of the cheeks and of lips that can close behind the teeth. This adaptation permits the muskrat (and the beaver) to chew on stems and roots under water "with its mouth closed."
Of all plants available in marshes, cattails are most preferred as a food item. However, muskrats appear to thrive equally well on a diet of bulrushes, horsetails, or pondweeds, the last two constituting the basis of the diet in northern latitudes. They also eat a variety of other plants, including sedges, wild rice, and willows.
During the winter a thick layer of ice restricts the muskrat to the interior of the lodge or burrow and the watery environment beneath the ice. The animal’s highly developed diving abilities and its use of push-ups become critical in procuring food under those conditions. It covers considerable distances under the ice searching for food. When the muskrat reaches a feeding area it chews off portions of plants and carries them to the nearest push-up, where it eats. This foraging activity under perhaps a metre of ice and snow, in ice-cold water and almost total darkness, is truly a remarkable feat.
When their normal food items are scarce or unavailable, and food of animal origin is abundant, muskrats are known to be highly carnivorous, or meat-eating. Under these circumstances muskrats most commonly consume animals such as fish, frogs, and clams. However, muskrats rarely do well on this type of diet and consuming such foods is generally taken to be evidence of hard times.
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All info I took out of here: http://www.hww.ca/hww2.asp?id=96
All pictures I took out of Google: http://www.google.es/imghp?hl=es&tab=wi
All pictures I took out of Google: http://www.google.es/imghp?hl=es&tab=wi