Muntiacus reevesi and other members of the Cervinae subfamily are interesting to geneticists due to their strange genetic history. It appears that while M. reevesi is 2n=46, M. feae is 2n=14 F/13 M, M. crinifrons and M. gongshanenis are 2n=8 F/9 M, and M. muntjak is 2n=6 F/7 M, the smallest known chromosome number for any mammal. It is also noted that evolution from the more primitive to more derived Muntiacus species was rapid, with the fastest evolution occurring in M. feae, where two different karyotypes emerged in only 0.5 Myr. Taxonomists recently added a potential new genus Megamuntjacus to the subfamily Cervinae, although it is still being disputed whether or not this new species should be its own genus or should fall under the genus Muntiacus.
Muntiacus reevesi, as a member of the Muntiacus genus, is often known as a barking deer, yet the function of barking may be overestimated by casual observers. While it was originally thought that muntjacs used their barks to communicate with other muntjacs to communicate danger or location information, it appears that the barks of muntjacs have a more limited function than expected. Barks are primarily used in two circumstances; when predators are suspected in the environment and during social encounters when subordinate and dominant animals come into contact. The hypothesis that barks are used as a part of reproductive processes has not been substantiated. Likewise, expectations that barks were used to communicate danger to other muntjacs could not be corroborated in studies. The frequency of the barks of muntjacs prevents them from traveling any substantial distance, particularly in dense vegetation, so it is unlikely that barks evolved as a warning response. It has been hypothesized that the barking of muntjacs is actually a vocalization of inner anxiety that accompanies being hunted by predators or challenged by a dominant individual and that it has little to do with mating, defending territory, food procurement or identification of individuals. Evidence supporting this hypothesis is found in the observations of increased barking by the muntjac at dawn and dusk and in environments that have decreased visibility, such as very dense grassland environments.
Chinese muntjacs send signals to others about their identity, their territory and their sexual state using a combination of non-bark vocalizations and chemicals. The non-bark vocalizations that may be emitted by Muntiacus reevesi are used in reproductive situations where the male makes a buzzing sound and a female that is willing will make a cat-like whine. A main form of communication in M. reevesi comes through chemicals emitted by the preorbital gland. These chemicals are used as scent markers to define territories and to advertise presence of an individual. Studies have shown that the chemical composition of these secretions would permit muntjacs to identify an individual’s age, sex and population of origin, but the mere presence of these capabilities within the chemical does not mean that the muntjac are using chemical communication in that way.
Communication Channels: acoustic ; chemical
Other Communication Modes: pheromones ; scent marks
Perception Channels: tactile ; acoustic ; chemical
Muntiacus reevesi is common in southeast China, therefore it is not listed as a threatened or endangered species. It appears not to have been studied by many conservation organizations, which most likely indicates that it is not a species of concern for those involved in protecting biodiversity.
US Federal List: no special status
CITES: no special status
IUCN Red List of Threatened Species: least concern
Muntiacus reevesi does not have any reported negative impacts in its native habitat because its populations are controlled by predator species and because it tends to live in forest environments. In England, however, M. reevesi, unchecked by predators, has become the most widely distributed deer and has been found to inhabit urban and suburban areas, as well as forests. They may be a nuisance to farmers and foresters due to their browsing on vegetation, particularly coppice.
Negative Impacts: crop pest
Muntiacus reevesi has positive impacts for humans in both China and western European feral populations. In both environments, M. reevesi is hunted for meat (and in Britain, for sport). They have also been appreciated in their native environments for warning humans in the woods of the presence of a predator animal, such as a tiger or leopard, with their barks.
Positive Impacts: food
The alarm barks of Chinese muntjacs are excellent warnings for other small mammals that a predator, such as a tiger or leopard, is in the area. In China, the behavior and distribution of M. reevesi is interdependent with the behavior and distribution of other Cervinae species, especially M. crinifrons, M. muntjak and Elaphodus cephalophus. As the most generalized in its food habits of the muntjacs, M. reevesi has the widest range, preferring subtropical forest areas and tending to occur near water. The other Cervinae species have become distributed in either higher elevations, drier, open environments, or wetter, denser environments. These habitat types have led the other Cervinae to become more specialized in their diet and behavior than M. reevesi.
The impacts of muntjacs and other deer on plant diversity and woodland invertebrates in England have been studied and it appears that with natural deer populations, vegetation browsing may create more habitats for invertebrates and the presence of dung may allow for an increased diversity of invertebrates. This is contrasted with high-density deer populations, where deer will overbrowse an area and leave minimal plant diversity and reduce remaining plant quality for invertebrates. Similar impacts have been observed on small mammal populations, where muntjacs may act as direct competitors for resources or act as habitat modifiers. Just as with the invertebrate study, observations made about Chinese muntjacs’ impact on small mammals are density-dependent. Essentially, at high densities, the competition for resources and habitat modification through loss of cover will cause a decline in the populations of small mammals (such as Apodemus sylvaticus, Micromys minutus, Sorex anareus, Sorex minutus, Myodes glareolus, Apodemus flavicollis, Muscardinus avellanarius) that ripples through the food chain, especially affecting the predators of small mammals: Mustela nivalis, Mustela erminea and Vulpes vulpes.
Ecosystem Impact: creates habitat; keystone species
Muntiacus reevesi is surprisingly omnivorous. It eats bamboo, seeds, bark, fruit and foliage, as most other deer species, but it has also been found to eat eggs and carrion and is reported to be able to hunt small mammals and ground-nesting birds. It is reported to eat hunters' snared pheasants in China. In China, M. reevesi tends to be aggressively defensive of its territory because while food is available year-round, it is not plentiful.
Animal Foods: birds; mammals; eggs; carrion
Plant Foods: leaves; wood, bark, or stems; seeds, grains, and nuts; fruit; flowers
Other Foods: fungus
Primary Diet: omnivore
Muntiacus reevesi has a native range that extends throughout the subtropical forests of southeastern China and Taiwan. It has also become established in England after being introduced at Woburn, England (located in the middle of Bedfordshire county) around 1900. Feral populations may also exist in France, where introduced individuals escaped gardens and zoos.
Biogeographic Regions: palearctic (Introduced ); oriental (Native )
Muntiacus reevesi is a forest creature in its native country of China. It creates paths through the subtropical rainforests at moderate elevations, which is why it has been termed by some as a bush hugger. It was observed that muntjacs in general tend to prefer habitats near streams, but evidence of this preference is not strongly demonstrated in the literature for this particular species of muntjac. Chinese muntjacs will fight to defend a fairly specific territory, but males have been shown to tolerate the presence of a subordinate male in their territory so long as that male is not in rut.
In England, M. reevesi exhibits slightly different preferences for habitat. It appears that the feral muntjacs of Britain are equally happy in habitats with and without cover; that is, muntjacs have been found in deciduous and coniferous forests as well as agricultural land, and even suburban and urban areas. In some respects, it is difficult to consider habitat preferences when a number of the metapopulations within the British population were specifically released into certain environments, so their presence in some habitats may not actually be an indication of a preference.
Reliable information on elevation preferences could not be found for the British population of M. reevesi, but in its native environment, it appears that M. reevesi prefers moderate elevations (moderate was not defined).
Habitat Regions: temperate ; tropical
Terrestrial Biomes: forest ; rainforest ; scrub forest
Other Habitat Features: urban ; suburban ; agricultural
Little is known about the lifespan of M. reevesi in the wild. Anecdotal evidence would indicate that Chinese muntjacs, which are described as a duiker-like (for example, Cepalophus niger) organism due to its rapid development and its generalist tendencies, would probably have a similar life expectancy: 10 to 12 years. In England, with a lack of predators and abundant food sources, it may be expected that Chinese muntjacs may live even longer.
Range lifespan
Status: wild: unknown (low) hours.
Range lifespan
Status: captivity: 18 (high) years.
Average lifespan
Status: wild: 10-12 years.
Average lifespan
Status: captivity: 23.2 years.
Muntiacus reevesi has a chestnut-colored coat with a 4-inch tail that is black above and white below. It has been reported that the females tend to be slightly lighter in color than males, but these observations were mainly made on captive and feral M. reevesi in England and have not been corroborated with observations of M. reevesi in its native China. Chinese muntjacs stand 43 to 45 cm in height at the shoulder.
Sexual dimorphism in M. reevesi leads to larger, heavier males that have short antlers (125 to 150 mm) that grow from their pedicles and that have long, tusk-like canines (1 to 2 inches long). The canines are not entirely fixed to the premaxilla so they are less likely to be broken off during a fight. Both the male and female Chinese muntjacs have bony ridges on their faces that are lined with black hair along the inside. These ridges extend into hair-covered pedicles from which antlers (male) or black tufts of hair (females) project. Both the male and female Chinese muntjacs also have preorbital glands that produce a creamy liquid used for chemical communication.
As with all Muntiacus species, M. reevesi has only the upper parts of the 2nd and 5th digit metacarpals present, a physiology known as plesiometacarpalia. However, unlike other deer species that have 2 hooves of the same size and shape, M. reevesi has one hoof that is smaller than the other and that is lined with hairs that are visible in its footprints.
Range mass: 11 to 28 kg.
Average mass: 18 kg.
Range length: 700 to 1130 mm.
Average length: 800 mm.
Other Physical Features: endothermic ; homoiothermic; bilateral symmetry
Sexual Dimorphism: male larger; sexes colored or patterned differently; ornamentation
Muntiacus reevesi is predated upon by a number of larger mammals and reptiles in southeast China. These natural enemies include leopards, tigers, dholes, jackals, crocodiles and pythons. In the introduced populations in England, the only potential predator is the fox. Behavioral differences may be noted between the English populations and those of China as the lack of predators leads M. reevesi to be much less vigilent in England and is therefore considered to be comfortable with the presence of man and human-altered surroundings.
When alarmed, Chinese muntjacs will bark for up to one hour. This distress call, however, does not appear to be meant to warn others but may simply be a vocalized expression of internal anxiety. This is mainly evidenced by the fact that muntjac barks tend to be emitted within a frequency range that would not carry through the dense vegetation that they inhabit.
Known Predators:
Males gain access to females by defending territory that overlaps that of females. The males will fight with the tusk-like canines for access to females in estrous. The males do not use their antlers in offensive moves while fighting like the white-tailed deer Odocoileus virginianus, but they spar extensively while still young, and use the horns in defensive moves while fighting.
Mating System: polygynous
Muntiacus reevesi has year round breeding in its natural habitat in China. In England, Chinese muntjacs appear to have a more seasonal breeding cycle that occurs between late October and early March. Both sexes of M. reevesi develop rapidly so that they may reach their reproductive threshold weights (12 kg for bucks, 10 kg for does) within a few months of birth (36 weeks for bucks, 24 weeks for does). It is unlikely that very young males will be able to gain access to a doe in estrus, but younger males tend to be more reproductively successful than older males due to the quality of their canines.
Unlike other antlered deer, muntjacs use tusk-like canines to defend territory and gain access to females. When a doe in estrus is located, the male will make a buzzing sound and the female will respond by lying flat, weaving her head and emitting a cat-like whine that is a sign of submission. After copulation, male are no longer involved with the females and once the rut is over, males lose their antlers. Males may grow antlers in a period as rapid as 103 days, which is useful for a species that can breed year-round.
Breeding interval: The mean inter-birth interval is approximately 233 days.
Breeding season: Breeding can occur year round in the subtropics, but in England, the breeding tends to be somewhat seasonal, occuring between late October and early March.
Range number of offspring: 1 to 2.
Average number of offspring: 1.
Range gestation period: 6.97 to 7.33 months.
Average gestation period: 7 months.
Average weaning age: 2 months.
Average time to independence: 6 months.
Range age at sexual or reproductive maturity (female): 24 (low) weeks.
Range age at sexual or reproductive maturity (male): 36 to 59 weeks.
Key Reproductive Features: iteroparous ; year-round breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; viviparous ; post-partum estrous
Average birth mass: 1050 g.
Average number of offspring: 1.
Parental investment is minimal in M. reevesi. The young develop extremely rapidly and are weaned early enough so that by the time that the caloric needs of the young really begin to escalate, they have begun to eat solid foods and are no longer dependent on their mother’s milk. Lactation generally occurs for only the first 17 weeks. Because the young become independent so early, there is no extra cost to a female to produce males (which would generally cost more in nutritional needs from a mother). By the age of 6 months, adulthood is reached and the young must leave the mother's territory.
Parental Investment: precocial ; pre-weaning/fledging (Provisioning: Female, Protecting: Female); pre-independence (Protecting: Female)
