Geographic Range
Large eared pikas,
Ochotona macrotis
, are most frequently found on the Qinghai-Tibet Plateau in Central Asia, as well
as in the Tienshan and Pamir mountain ranges. This species of ochotonid is also encountered
in the Nepal Himalayas, Punjab, and Kashmir, as well as in remote areas surrounding
China's western forests in the Sinkiang Province.
- Biogeographic Regions
- palearctic
Habitat
In general, pikas establish nests among rocky debris on talus slopes formed by glaciers. The rocks serve as both a home and refuge against predators. The size of the rocks is important for pikas because these animals use natural crevices and tunnels to travel from one location to another. Spaces that are too large may permit predators to reach the pikas.
One can often identify the presence of a pika by the presence of droppings. Pellets
are usually confined in consistent piles among the talus. Rocks with crusty white
urine stains also suggest pika presence. This particular species can occur at elevations
as high as 6,100 m.
- Habitat Regions
- temperate
- terrestrial
- Terrestrial Biomes
- mountains
Physical Description
Large-eared pikas are similar physically to Ochonta royalei , but with larger ears. These animals are approximately 150 to 200 mm in length. They can weigh up to 120 g.
This particular ochotonid has the largest pinnae of any member of the family, hence its common name. Like other lagomorphs, ochotonids have an extra pair of insisors behind the first. The pelage is thick, soft, and slightly silky. Unlike rabbits and hares, ochotonids have visible toe pads surrounded by well furred feet.
Among pikas in general, two molts occur yearly which vary in color, due to seasonal changes. Females often lose their fur later in the season than male ochotonids. It has been suggested that sexual differences in timing of molt is related to reproduction.
The metabolic rate of ochotonids is high, particularly those species such as
O. macrotis
, which experience harsh climates and conditions with much snow.
- Other Physical Features
- endothermic
- bilateral symmetry
Reproduction
These animals appear to mate polygynously. It is not known whether courtship exists
among ochotonids. As in other lagomorphs, ovulation is induced by copulation. Suprisingly,
aggressiveness among male ochotonids is reduced during the onset of female reproduction.
It is not until the young are slightly grown that males become territorial. The most
severe period of male agressiveness occurs during the fall, after reproduction has
occured. During mid-summer, males become highly territorial and aggressive male-male
chases occur once per hour.
- Mating System
- polygynous
Both male and female large-eared pikas become sexually mature around one year of age. Mating takes place during a short period in the early summer. Gestation lasts only 30 days. Reproductive capacity is low, with a typical litter of two pups. It has been suggested that this phenomenon is linked to the short mating season of O. macrotis . Large-eared pikas mature quickly, with time to weaning lasting only a month.
By one year of age, males stake out new territories and will often tresspass onto
those of an adjacent males. Females, on the other hand, usually remain in one area
until a mate is chosen.
- Key Reproductive Features
- iteroparous
- seasonal breeding
- gonochoric/gonochoristic/dioecious (sexes separate)
- sexual
- induced ovulation
- fertilization
- viviparous
As with most mammals, male pikas do not extend any care to their offspring. Instead,
females provide their young with protection, food, and grooming. By one week of age,
the newly born pikas begin walking and making vocalizations.
- Parental Investment
- altricial
-
pre-fertilization
- provisioning
-
protecting
- female
-
pre-hatching/birth
-
provisioning
- female
-
protecting
- female
-
provisioning
-
pre-weaning/fledging
-
provisioning
- female
-
protecting
- female
-
provisioning
Lifespan/Longevity
Although data for
O. macrotis
are lacking, it is thought that pikas in general have a lifespan of one to three
years. Long-earned pikas are likely to have a similar maximum lifespan.
Behavior
Like other pikas, large-eared pikas do not hibernate during the winter. Whereas other species are active throughout the day, O. macrotis is the most active around mid-day. The remainder of the day is spent crouching on prominent rocks, sun-bathing, or watching for predators. If the temperature is too high, animals take refuge for extended periods of time beneath the talus.
Unlike other pikas, O. macrotis does not perform the typical hay-gathering ritual that often comes to be associated with ochotonids. Hay-gathering involves the cutting and drying of grasses, which are stacked in piles among the rocks for later use as bedding and food.
Pikas are typically more alert of their surroundings after the snow has melted than at any other time of the year because of their prolonged absence from the outside world. The loss of the snow, which provided temoporary protection, makes the ochotonids more accessible to predators.
Behavior also changes through the course of the season, from the time of the breeding
season to after the offspring are born. Trespassers are often allowed to cross boundaries
during certain times of the year, but not during others.
- Key Behaviors
- terricolous
- diurnal
- motile
- sedentary
- solitary
- territorial
Communication and Perception
Ochontids typically use sharp, high-pitched whistles to communicate with each other.
Such calls are often used when predators are close at hand. Calls vary in range and
pitch for different classes of predators. Vocalizations are also used to advertize
territorial boundaries. Barks against invasive males are frequent during the mating
months. Like other Asiatic species, large-eared pikas have been known to give nocturnal
calls. Suprisingly, neither
O. macrotis
and
O. royalei
are as vocal as other pika species. Because thse animals rely less on vocalizations
as a means of communication, it has been suggested that
O. macrotis
uses other methods of communication, such as pheromones.
As in all diurnal species, visual communication, including body posture, is probably important between conspecifics. Tactile communication occurs between mates, rivals, and between mothers and their young.
- Other Communication Modes
- scent marks
Food Habits
In general, pikas eat all available plant vegetation such as grasses, sedges, twigs, and flowers. During the first month after winter, there is a great deal of competition to consume new vegetation. Consumption of grasses and other plant-foods occurs fromt the end of the matter that has been bitten off. Lichens and mosses are also eaten if they are present and nearby pika dwellings. Ochontids use pathways to travel between feeding grounds.
Because pikas do not hibernate and food storage often runs low during late winter, they typically forage continuously during the winter months. When snow cover is heavy, pikas dig tunnels from their burrows to tree trunks. In the absence of other forage, pikas may nibble away the tree bark.
Two fecal types are produced, including a gelatinous, green excrement. To obtain vitamin
B and other nutrients, pikas, like all lagomorphs, will consume their feces.
- Plant Foods
- leaves
- wood, bark, or stems
- seeds, grains, and nuts
- flowers
- bryophytes
- lichens
- Other Foods
- dung
- Foraging Behavior
- stores or caches food
Predation
Pikas are particularly vulnerable to weasels, canines, hawks, and owls and calling
has evolved to alert nearby indivuals of approaching danger. Generally, there is a
sentinel on the alert for strange sounds and movements. This individual often watches
from a slope with an adequate view. Barks are initiated at the first sign of danger.
Sentinals can escape to a nearby crevice for their own safety. Pikas usually take
cover in the rocky debris when two short, distinctive calls, typical of an aerial
predator, are given by the sentinel. When weasles are spotted, vocalization is generally
restrained, and pikas hearing the call will silently escape and take cover. The strategy
is different for avian and terrestrial predators because runways and tunnels are differentially
accessible by these predators.
Ecosystem Roles
To the extent that these animals serve as prey, they have impact in local food webs. In addition, they are likely to influence local plant communities through their foraging behavior.
Economic Importance for Humans: Positive
These pikas have no known positive impact on human economies. Although other pikas
make hay piles that can be used by domestic animals grazing in the area, this species
is not known to make such hay piles.
Economic Importance for Humans: Negative
Large-eared pikas have been known to creep in and live among the walls of homes near
their territory. In such circumstances, unattended food around the house is often
nibbled at or stolen away to the nests.
- Negative Impacts
- household pest
Conservation Status
This species is not a conservation concern.
Other Comments
Ochotona macrotis
and
O. royalei
have in the past been classified by taxonomists as the same species. However, modern
day genetics suggests that they are separate species.
Ochotona macrotis
occurs at a higher elevation than its sister group,
O. royalei
.
Additional Links
Contributors
Dana Jordan (author), Humboldt State University, Brian Arbogast (editor, instructor), Humboldt State University.
Nancy Shefferly (editor), Animal Diversity Web.
- Palearctic
-
living in the northern part of the Old World. In otherwords, Europe and Asia and northern Africa.
- native range
-
the area in which the animal is naturally found, the region in which it is endemic.
- temperate
-
that region of the Earth between 23.5 degrees North and 60 degrees North (between the Tropic of Cancer and the Arctic Circle) and between 23.5 degrees South and 60 degrees South (between the Tropic of Capricorn and the Antarctic Circle).
- terrestrial
-
Living on the ground.
- mountains
-
This terrestrial biome includes summits of high mountains, either without vegetation or covered by low, tundra-like vegetation.
- polygynous
-
having more than one female as a mate at one time
- iteroparous
-
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).
- seasonal breeding
-
breeding is confined to a particular season
- sexual
-
reproduction that includes combining the genetic contribution of two individuals, a male and a female
- induced ovulation
-
ovulation is stimulated by the act of copulation (does not occur spontaneously)
- fertilization
-
union of egg and spermatozoan
- viviparous
-
reproduction in which fertilization and development take place within the female body and the developing embryo derives nourishment from the female.
- altricial
-
young are born in a relatively underdeveloped state; they are unable to feed or care for themselves or locomote independently for a period of time after birth/hatching. In birds, naked and helpless after hatching.
- diurnal
-
- active during the day, 2. lasting for one day.
- motile
-
having the capacity to move from one place to another.
- sedentary
-
remains in the same area
- solitary
-
lives alone
- territorial
-
defends an area within the home range, occupied by a single animals or group of animals of the same species and held through overt defense, display, or advertisement
- visual
-
uses sight to communicate
- tactile
-
uses touch to communicate
- acoustic
-
uses sound to communicate
- chemical
-
uses smells or other chemicals to communicate
- scent marks
-
communicates by producing scents from special gland(s) and placing them on a surface whether others can smell or taste them
- visual
-
uses sight to communicate
- tactile
-
uses touch to communicate
- acoustic
-
uses sound to communicate
- chemical
-
uses smells or other chemicals to communicate
- stores or caches food
-
places a food item in a special place to be eaten later. Also called "hoarding"
- herbivore
-
An animal that eats mainly plants or parts of plants.
- folivore
-
an animal that mainly eats leaves.
- endothermic
-
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.
- bilateral symmetry
-
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.
References
MacDonald, D. 1984. The Encyclopedia of Mammals . New York: Facts on File, Inc..
Orr, R. 1977. The Little-Known Pika . New York: Macmillan Publishing Co., Inc..
Yidong, N., W. Fuwen, L. Ming, L. Xiaoming, F. Zuojian. 2004. Phylogeny of pikas (Lagomorpha, Ochotona) inferred from mitochondrial cytochrome b sequences. Folia Zool. , 53(2): 141-155.