Indus River dolphins are roughly the same color as the river, gray or brown, though they sometimes are lighter on their undersides. Their “beaks” are distinctively swollen at the tip and very long, reaching 20% of the length of their bodies, with large, visible teeth. In contrast to their “beaks”, their dorsal fins are rather small and reduced compared to other river dolphins. Large flippers and flukes, combined with long and remarkably flexible necks, probably help the dolphins navigate effectively. Platanista gangetica barely differ physically except for slight differences in tail lengths, the two species are distinguishable by their ranges. lives only in the Indus River system, while Platanista gangetica only inhabits the Ganges River system. Females are larger than males. (Moreno, 2004)has external ears located below their eyes, but their eyes are very small and probably can only see shadowy, unclear images. Though and
These dolphins probably do not mate seasonally, since calves are born at different times throughout the year. However, in a captive population of two females and a male in Switzerland, the male reportedly chased the females in the spring. Though scattered captive populations of Platanistidae family. (Herman, 1980; Moreno, 2004)exist, little is known about the mating behavior of any of the members of the
Little information is available about parental investment in (Moreno, 2004), however, they most likely spend much time and energy on their offspring. Since females are pregnant for up to 11 months, newborns are about half the size of their mothers at birth, calves nurse up to a year after birth, Indus River dolphin offspring are probably very costly.
No data is available about the home range of Platanista gangetica, however, has been reported at densitites of 0.7-1.36 dolphins per kilometer. Perhaps also require about a kilometer of space each, though data is still absent to determine how far they travel. All that is known is that they appear to migrate seasonally along the river. (Smith, et al., 2001).
Indus River dolphins have extremely poor eyesight, perhaps since vision is nearly useless to navigate the murky rivers in which they live. They instead rely on echolocation to perceive their environment. Indeed, one of the common names for (Moreno, 2004)is “blind river dolphin”. Their external ears might help receive echolocation signals, which are intermittent pulses rather than continuous whistles. Though Indus River dolphins are very vocal, they use sounds for communication only about 5% of the time that they vocalize.
Indus River dolphins use their echolocation abilities combined with their highly toothed, long snouts to forage for many bottom-dwelling animals including fish and invertebrates. catfish, herring, carp, gobies, mahseers, prawns, and clams. Captive individuals reportedly consume about a kilogram of food each day. (Moreno, 2004)has been known to eat some species of
Indus River dolphins each eat about a kilogram of benthic fish and invertebrates daily, it is not clear how strongly they impact any of their prey populations. (Moreno, 2004)
Some people hunt Indus River dolphins for their meat and oil. People in some areas eat the dolphin meat, while others use it as a fishing lure, though studies indicate that fish flesh is just as effective. The dolphin’s oil is used for medicinal purposes, its supposed effectiveness as an aphrodisiac, and to rub on one’s skin. (Moreno, 2004; Sinha, 2002)
Some authors consider Platanista gangetica, others consider them the same species, and others consider them distinct species. Genetic analysis has not yet answered the taxonomic mysteries of the Platanistdae family. (Moreno, 2004; Hamilton, et al., 2001; Moreno, 2004)to be a subspecies of
Matthew Wund (editor), University of Michigan-Ann Arbor.
Rachel Bricklin (author), University of Michigan-Ann Arbor, Phil Myers (editor, instructor), Museum of Zoology, University of Michigan-Ann Arbor.
uses sound to communicate
Referring to an animal that lives on or near the bottom of a body of water. Also an aquatic biome consisting of the ocean bottom below the pelagic and coastal zones. Bottom habitats in the very deepest oceans (below 9000 m) are sometimes referred to as the abyssal zone. see also oceanic vent.
having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.
areas with salty water, usually in coastal marshes and estuaries.
an animal that mainly eats meat
uses smells or other chemicals to communicate
a substance used for the diagnosis, cure, mitigation, treatment, or prevention of disease
The process by which an animal locates itself with respect to other animals and objects by emitting sound waves and sensing the pattern of the reflected sound waves.
animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.
A substance that provides both nutrients and energy to a living thing.
mainly lives in water that is not salty.
offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).
having the capacity to move from one place to another.
specialized for swimming
the area in which the animal is naturally found, the region in which it is endemic.
found in the oriental region of the world. In other words, India and southeast Asia.
an animal that mainly eats fish
reproduction that includes combining the genetic contribution of two individuals, a male and a female
associates with others of its species; forms social groups.
uses touch to communicate
reproduction in which fertilization and development take place within the female body and the developing embryo derives nourishment from the female.
breeding takes place throughout the year
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