The northern pig-tailed macaque (''Macaca leonina'') is a vulnerable species of
macaque in the subfamily
Cercopithecidae.
It is found in
Bangladesh
Bangladesh (}, ), officially the People's Republic of Bangladesh, is a country in South Asia. It is the eighth-most populous country in the world, with a population exceeding 165 million people in an area of . Bangladesh is among the mos ...
,
Cambodia
Cambodia (; also Kampuchea ; km, កម្ពុជា, UNGEGN: ), officially the Kingdom of Cambodia, is a country located in the southern portion of the Indochinese Peninsula in Southeast Asia, spanning an area of , bordered by Thailan ...
,
China,
India
India, officially the Republic of India (Hindi: ), is a country in South Asia. It is the seventh-largest country by area, the second-most populous country, and the most populous democracy in the world. Bounded by the Indian Ocean on the so ...
,
Laos,
Myanmar
Myanmar, ; UK pronunciations: US pronunciations incl. . Note: Wikipedia's IPA conventions require indicating /r/ even in British English although only some British English speakers pronounce r at the end of syllables. As John Wells explai ...
,
Thailand
Thailand ( ), historically known as Siam () and officially the Kingdom of Thailand, is a country in Southeast Asia, located at the centre of the Indochinese Peninsula, spanning , with a population of almost 70 million. The country is b ...
, and
Vietnam
Vietnam or Viet Nam ( vi, Việt Nam, ), officially the Socialist Republic of Vietnam,., group="n" is a country in Southeast Asia, at the eastern edge of mainland Southeast Asia, with an area of and population of 96 million, making i ...
. Traditionally, ''M. leonina'' was considered a
subspecies of the
southern pig-tailed macaque
The southern pig-tailed macaque (''Macaca nemestrina''), also known as the Sundaland pig-tailed macaque and Sunda pig-tailed macaque, is a medium-sized macaque that lives in southern Thailand, Malaysia, and Indonesia. It is known locally as ber ...
(''M. nemestrina''), but is now classified as an individual species.
In the 21st century, the pig-tailed macaque was split into the northern pig-tailed macaque species ''Macaca leonina'' and the Sundaland pig-tailed macaque species ''M. nemestrina''.
This reclassification was aided by the observation of
sexual swelling
Sexual swellings are enlarged areas of genital and perineal skin occurring in some female primates that vary in size over the course of the menstrual cycle. Thought to be an honest signal of fertility, male primates are attracted to these swell ...
s and basic attributes that distinguish the two.
The northern pig-tailed macaque is
frugivorous
A frugivore is an animal that thrives mostly on raw fruits or succulent fruit-like produce of plants such as roots, shoots, nuts and seeds. Approximately 20% of mammalian herbivores eat fruit. Frugivores are highly dependent on the abundance an ...
and their social grouping is
matriarchal, where
sexual dimorphic traits can distinguish males and females.
Their adaptation to
omnivorous
An omnivore () is an animal that has the ability to eat and survive on both plant and animal matter. Obtaining energy and nutrients from plant and animal matter, omnivores digest carbohydrates, protein, fat, and fiber, and metabolize the nut ...
diets occur in periods of fruit scarcity, munching on wild vegetation and crops, human foods, and small insects and mammals.
Despite their adaptability, northern-pig tailed macaques experience viral threats such as the
human immunodeficiency virus type 1, pathogenic simian immunodeficiency, and coronavirus.
Human impacts are also present, such as agricultural expansions,
aquaculture, transportation infrastructure, hunting and logging for meat and trophies, and the illegal
pet trade
Wildlife trade refers to the of products that are derived from non-domesticated animals or plants usually extracted from their natural environment or raised under controlled conditions. It can involve the trade of living or dead individuals, ti ...
; that result in habitat loss, forest fragmentation, and a reduced well-being.
Physical characteristics
Appearance
Physical characteristics identifiers in distinguishing the northern and the southern pig-tailed macaques.
Northern pig-tailed macaques have a round greyish
pelage
Fur is a thick growth of hair that covers the skin of mammals. It consists of a combination of oily guard hair on top and thick underfur beneath. The guard hair keeps moisture from reaching the skin; the underfur acts as an insulating blanket ...
from the side of their cheeks all the way around to the top of their head and beneath their chin, which is called a crown.
A brown pelage patch is found on the centre of their crowns followed by white triangular forms beneath this patch and along the top of their eyes.
One red stripe is found at each exterior corner of their eyes which are angled upwards and diagonally meeting at the ending point of the white triangular eye extremities.
Their elongated muzzle is still shorter when compared to southern pig-tailed macaques.
On their backs, for mostly males, a black streak is found at the centre; and can sometimes have a red hue towards the top and black towards the bottom.
Moving downwards, their tails are composed of a thin pelage in a dark blackish hue and are shorter and skinner than southern pig-tailed macaques.
Tail shapes vary, however, the most common is a 90 degree point to the back, followed by a 45 degree, a forward and parallel, a forward arch meeting its back, pointed downwards.
Beneath their tail, on their backside, there are oval shaped thick sitting pads that cover their hip bones, known as
ischial callosities.
Sex Differences
The northern-pig tailed macaques have
sexual dimorphic traits.
Body weight is the most obvious indicator to distinguish males from females, where males are found over eight kg give or take, and females below six kg.
Adult males are identified with defined shoulder musculature and exhibit red coloured sexual organs, such as their penis and anus.
Their tails are also found to be longer relative to females and their pelage has more darker contrast to it.
Adult females are smaller in size and are found to have
sexual swelling
Sexual swellings are enlarged areas of genital and perineal skin occurring in some female primates that vary in size over the course of the menstrual cycle. Thought to be an honest signal of fertility, male primates are attracted to these swell ...
in the same regions, yet are more vibrant red than in males.
Male teenagers, known as subadult males, do not have red coloured sexual organs, yet have dropped testicles.
Infants fit into the age range of five to eight weeks old and are usually found eating solid foods, yet those older than nine weeks are studied to be independent of their mothers until a certain distance is travelled.
Newborns are up to four weeks old usually found feeding on breast milk, and are usually near their mother's stomachs while in motion or are cradled in their arms.
Distribution and Habitat
China
The ''Macaca leonina'' can also be found in tropical forests in
southwestern China
Southwest China () is a region in the south of the People's Republic of China.
Geography
Southwest China is a rugged and mountainous region, transitioning between the Tibetan Plateau to the west and the Chinese coastal hills (东南丘陵) and ...
.
A study conducted in the Naban River Watershed National Nature Reserve found that the species has a wider distribution and greater niche breath than ''Macaca mulatta'' based on camera trapping data within the area.
Groups of ''Macaca leonina'' were found scattered in forests with higher elevations, more specifically broadleaved
evergreen forest
An evergreen forest is a forest made up of evergreen trees. They occur across a wide range of climatic zones, and include trees such as conifers and holly in cold climates, eucalyptus, Live oak, acacias, magnolia, and banksia in more temperate zo ...
s when compared to the other species.
Yet, they avoided rubber plantations as a result of their habitat being severely reduced in size, which restricted their ability to access food resources and blocked travel to other regions of the reserve.
With extensive data collection, the results showed that both species were well adapted to their degraded environment by consistently following daily activity budgets, including the regions chosen for preferred elevation and vegetation.
However, the season had an impact on both species activity budgets as it altered due to the presence of rainfall within
monsoon
A monsoon () is traditionally a seasonal reversing wind accompanied by corresponding changes in precipitation but is now used to describe seasonal changes in atmospheric circulation and precipitation associated with annual latitudinal osci ...
al periods.
In the dry-hot season, the space became more restricted to both species because the once vegetation rich region became limited and required a change of activity patterns for both species.
India
In India, the northern pig-tailed macaque is found south of the
Brahmaputra River, in the northeastern part of the country. Its range in India extends from Assam and Meghalaya to eastern Aruanchal Pradesh, Nagaland, Manipur, Mizoram and Tripura. A detailed report on the ecology and behaviour of northern pig-tailed macaque has been published in 2008.
Although no global population estimate is available, some site-based estimates are, including
Keo Seima Wildlife Sanctuary
Keo Seima Wildlife Sanctuary ( Khmer: ដែនជម្រកសត្វព្រៃកែវសីមា) is a protected area of mixed seasonal tropical forest in eastern Cambodia, located in Mondulkiri and Kratié provinces. The area was f ...
in Cambodia, where an increasing population of almost 4,000 is reported.
Thailand
Northern pig-tailed macaques are also found in
Northeastern Thailand
Northeast Thailand or Isan (Isan/ th, อีสาน, ; lo, ອີສານ; also written as Isaan, Isarn, Issarn, Issan, Esan, or Esarn; from Pali ''īsānna'' or Sanskrit ईशान्य ''īśānya'' "northeast") consists of 20 provin ...
shown to be impacted by anthropogenic influences such as deforestation and forest alterations.
Their home range sizes vary from 62 to 828 hectares, similar to the southern pig-tailed macaques ''Macaca nemestrina.''
However, their ability to travel is often limited due to habitat degradation and transformation with no limit to elevation unless there is less canopy cover per area.
In the Sakaerat Biosphere Reserve, the region was about eighty kilometres of
dry evergreen forest
An evergreen forest is a forest made up of evergreen trees. They occur across a wide range of climatic zones, and include trees such as conifers and holly in cold climates, eucalyptus, Live oak, acacias, magnolia, and banksia in more temperate zon ...
,
old growth acacia forest, and
dry dipterocarp forest; yet it slowly transformed into fragments of
eucalyptus
''Eucalyptus'' () is a genus of over seven hundred species of flowering trees, shrubs or mallees in the myrtle family, Myrtaceae. Along with several other genera in the tribe Eucalypteae, including '' Corymbia'', they are commonly known as e ...
plantations, agricultural expansions, highway constructions, and human settlements.
This change of native habitat eventually led to a study in 2017 and 2018 by Gazagne et al., observing a range of 128 and 150 northern pig-tailed macaques and their selection of 107 sleeping sites.
Some examples of potential predators in this region are the clouded leopard ''
Neofelis nebulosa'' and two species of pythons known as ''
Python reticulatus
The reticulated python (''Malayopython reticulatus'') is a python species native to South and Southeast Asia. It is the world's longest snake, and is among the three heaviest. It is listed as least concern on the IUCN Red List because of its w ...
'' and ''
Python bivittatus''.
The authors found that the macaques still preferred sleeping sites with two layers of
canopy
Canopy may refer to:
Plants
* Canopy (biology), aboveground portion of plant community or crop (including forests)
* Canopy (grape), aboveground portion of grapes
Religion and ceremonies
* Baldachin or canopy of state, typically placed over an ...
for protection, however no predator conflicts were recorded nor impacting site selection.
The authors then concluded that food proximity had a larger influence on the sleeping site selection than canopy, since food sites were often found near their sleeping sites or they were sleeping within them.
The scattered food availability and reduced sleeping sites also contributed to forming the largest social group of northern pig-tailed macaques observed.
Ecology and Behaviour
Diet
Northern pig-tailed macaques are
frugivorous
A frugivore is an animal that thrives mostly on raw fruits or succulent fruit-like produce of plants such as roots, shoots, nuts and seeds. Approximately 20% of mammalian herbivores eat fruit. Frugivores are highly dependent on the abundance an ...
as they tend to forage for hundreds of fruit species such as fleshy and dry; as well as flowers and buds, piths, leaves, and shoot species that makeup more than fifty percent of their diet.
Due to limited fruit availability in colder seasons or with habitat degradation, the macaques are found to become more
omnivorous
An omnivore () is an animal that has the ability to eat and survive on both plant and animal matter. Obtaining energy and nutrients from plant and animal matter, omnivores digest carbohydrates, protein, fat, and fiber, and metabolize the nut ...
due to reliance on human food resources such as "rice, bread, biscuits"; and can also be found munching on fungi, ants, termites, spiders, stickbuds, grasshoppers, caterpillars, beetles, mushrooms, barks, eggs, lizards, and squirrels.
Group Strategies
Despite their limited and varied accessibility to their main food resources and habitat transformations, the northern pig-tailed macaques adapt to their environments by altering how their social groups are formed and composed.
Group sizes are shown to increase as a response to low
connectivity
Connectivity may refer to:
Computing and technology
* Connectivity (media), the ability of the social media to accumulate economic capital from the users connections and activities
* Internet connectivity, the means by which individual terminal ...
within feeding sites, and tend to become more
sedentary
Sedentary lifestyle is a lifestyle type, in which one is physically inactive and does little or no physical movement and or exercise. A person living a sedentary lifestyle is often sitting or lying down while engaged in an activity like soci ...
when relying on human food resources for nutrition.
The opposite is true for their group sizes and lifestyle within more wild environments, where smaller groups and
nomad
A nomad is a member of a community without fixed habitation who regularly moves to and from the same areas. Such groups include hunter-gatherers, pastoral nomads (owning livestock), tinkers and trader nomads. In the twentieth century, the po ...
ic patterns are more common.
Groups are fairly large within this species which can exceed over one hundred fifty individuals.
However, they split into smaller groups when feeding and rejoin for larger group travel.
They are also found to vary their home range depending on the season, as the fruit availability and quality varies.
In low fruit abundance periods, the macaques are shown to travel to human settlements, which Gazagne et al., say is a practice of a "high-cost, high yield foraging strategy" as seen within plantation forests.
Northern pig-tailed macaques are found to prefer fruits from
plantation forests when wild ones are scarce.
Their home range, however, increases as a result of high fruit abundance periods, where they are found settling near specific fruits species within forest habitats.
Therefore, they use different strategies to forage for food depending on what environments show abundance or low abundance, and their
seasonality
In time series data, seasonality is the presence of variations that occur at specific regular intervals less than a year, such as weekly, monthly, or quarterly. Seasonality may be caused by various factors, such as weather, vacation, and holidays a ...
.
When plantations are abundant, they are found using more energy costs to travel to the region due to its high yields, therefore they are likely to increase their travels and trajectories.
When wild resources are abundant, such as within
dry evergreen forests, the species uses less energy costs as they remain in smaller ranges to gain more yields.
However, with low abundance in both regions, the strategy is to create a balance between both strategies described above.
Mating & Reproduction
Social groups are
matriarchal just like all macaque species are, therefore females exercise dominance within social groups.
Mating occurs when females attract males with reddened sexual skin swellings which occur due to hormone fluctuations during
ovulation
Ovulation is the release of eggs from the ovaries. In women, this event occurs when the ovarian follicles rupture and release the secondary oocyte ovarian cells. After ovulation, during the luteal phase, the egg will be available to be fertilize ...
, their receptive period.
Female swellings are common signs of fertility that can continue past the
periovulatory period.
The receptive period is identified with continuous mating patterns, where males practice a single or multiple mount process, within a few days in a row.
A visible
sperm plug can also be identified during this period of
copulation
Sexual intercourse (or coitus or copulation) is a sexual activity typically involving the insertion and thrusting of the penis into the vagina for sexual pleasure or reproduction.Sexual intercourse most commonly means penile–vaginal penetra ...
.
The duration of female pregnancies exceed the eight-month period for a single
offspring
In biology, offspring are the young creation of living organisms, produced either by a single organism or, in the case of sexual reproduction, two organisms. Collective offspring may be known as a brood or progeny in a more general way. This ca ...
and are followed by
lactation
Lactation describes the secretion of milk from the mammary glands and the period of time that a mother lactates to feed her young. The process naturally occurs with all sexually mature female mammals, although it may predate mammals. The proces ...
for feeding newborns and infants up to two years of age.
Threats
Viruses
Viruses are a common threat among northern pig-tailed macaques within degraded environments. For example, nonpathogenic
human immunodeficiency virus type 1 (HIV-1NL4-3) and pathogenic simian immunodeficiency (SIVmac239) viruses present in northern pig-tailed macaques can determine their survival rates.
These two viruses were evaluated by Wen-Quiag et al. (2022), to understand how
interferon (IFN)-a had an impact on both viruses.
The result of both infections were taken from tissue samples from either
euthanized
Animal euthanasia ( euthanasia from el, εὐθανασία; "good death") is the act of killing an animal or allowing it to die by withholding extreme medical measures. Reasons for euthanasia include incurable (and especially painful) conditi ...
individuals with chronic infection or those who experienced natural death.
The researchers found that HIV-1 performed better, meaning that the infectious qualities and viral activity were less replicated within the immune system with (IFN)-a when compared to the pathogenic simian immunodeficiency virus.
They hypothesized that HIV's lower impact on the immune system in northern pig-tailed macaques can explain how HIV-1 does not reproduce and evolve into AIDS within the species.
The results show that naturally derived
IFN-a
The type-I interferons (IFN) are cytokines which play essential roles in inflammation, immunoregulation, tumor cells recognition, and T-cell responses. In the human genome, a cluster of thirteen functional IFN genes is located at the 9p21.3 cyto ...
is effective at preventing
HIV-1
The subtypes of HIV include two major types, HIV type 1 (HIV-1) and HIV type 2 (HIV-2). HIV-1 is related to viruses found in chimpanzees and gorillas living in western Africa, while HIV-2 viruses are related to viruses found in the sooty mangabey ...
from further long term reproduction, yet SIVmac239 needs to be monitored to prevent further chronic illness.
Northern pig-tailed macaques were also reported to be affected by
coronavirus 2 (SARS-CoV-2) and was shown to be fatal and highly transmissible.
Human Impacts
According to the ICUN red list, the northern pig-tailed macaque is considered vulnerable and declining.
This species is affected by human impacts such as agricultural expansions, aquaculture, transportation infrastructure, hunting and logging for meat and trophies, and the illegal pet trade; that result in habitat loss and forest fragmentation.
With these influences, this species is found raiding crops and their main sources of fresh nutrition are limited, minimally available, and less accessible depending on the season.
Pet trade
A study done between 2015 and 2019 in
Vietnam
Vietnam or Viet Nam ( vi, Việt Nam, ), officially the Socialist Republic of Vietnam,., group="n" is a country in Southeast Asia, at the eastern edge of mainland Southeast Asia, with an area of and population of 96 million, making i ...
, reported that the illegal
pet trade
Wildlife trade refers to the of products that are derived from non-domesticated animals or plants usually extracted from their natural environment or raised under controlled conditions. It can involve the trade of living or dead individuals, ti ...
of hundreds of primates were confiscated, released, and rescued and kept specific species at higher risk of physical and emotional threats.
The study reported that "32 Assamese macaques (''
Macaca assamensis''), 158 long-tailed macaques (''
Macaca fascicularis
The crab-eating macaque (''Macaca fascicularis''), also known as the long-tailed macaque and referred to as the cynomolgus monkey in laboratories, is a cercopithecine primate native to Southeast Asia. A species of macaque, the crab-eating macaque ...
''), 291 Northern pig-tailed macaques (''Macaca leonina''), 65 rhesus macaques (''
Macaca mulatta
The rhesus macaque (''Macaca mulatta''), colloquially rhesus monkey, is a species of Old World monkey. There are between six and nine recognised subspecies that are split between two groups, the Chinese-derived and the Indian-derived. Generally ...
''), and 110 stump-tailed macaques (''
Macaca arctoides
The stump-tailed macaque (''Macaca arctoides''), also called the bear macaque, is a species of macaque native to South Asia and Southeast Asia. In India, it occurs south of the Brahmaputra River, in the northeastern part of the country. Its ran ...
'')" were involved; showing that macaques are subject to the highest threats to pet trade in Vietnam.
The rare distribution of illegal pet permits can be one consequence, however the widespread misinformation on keeping smaller non-human primates as pets was found to be the underlying reason for such trades.
Macaques were also observed to be the least protected due to the misconception of their abundance and invasive qualities in human settlements.
The psychological impacts vary, however the researchers evaluated common roots of the cause such as
maternal deprivation
Maternal deprivation is a scientific term summarising the early work of psychiatrist and psychoanalyst John Bowlby on the effects of separating infants and young children from their mother (or primary caregiver). Although the effect of loss of t ...
and
social isolation
Social isolation is a state of complete or near-complete lack of contact between an individual and society. It differs from loneliness, which reflects temporary and involuntary lack of contact with other humans in the world. Social isolation ...
.
In consequence, macaques were found to have "
neophobia, persistent abnormal or stereotypical behaviors,
anaclitic depression and withdrawal, negatively affect plasma-cortisol levels,
cell-mediated immunity
Cell-mediated immunity or cellular immunity is an immune response that does not involve antibodies. Rather, cell-mediated immunity is the activation of phagocytes, antigen-specific cytotoxic T-lymphocytes, and the release of various cytokines in ...
, and
survivorship" (Aldrich & Neale, 2021).
Additionally, northern pig-tailed macaques were observed as the highest kept macaque out of the range of captive macaque species in Vietnam; and were found in various locations from cages on personal property to hotels and restaurants.
Due to exposure from non-governmental organizations, this issue started to gain awareness among the public and authorities, yet rescue centres are often at full capacity; which continues the cycle of releasing macaques without proper identification, protection, and disease screening.
The authors suggest data collection on the macaque species within Vietnam to address the severity of the pet trade on their survival and conservation, increasing the accessibility of confiscation and release records, training on confiscation and rehabilitation, and improving the global spread of information addressing the impacts of the pet trade on non-human primates survival and well-being.
Gallery
File:Northern pig-tailed macaque, Macaca leonina - khao yai national park.webm, Mother with infant in Khao Yai National Park
Khao Yai National Park ( th, อุทยานแห่งชาติเขาใหญ่, , ) is a national park in Thailand. Established in 1962 as Thailand's first national park, it is the third largest national park in Thailand.
Descri ...
, Thailand
Thailand ( ), historically known as Siam () and officially the Kingdom of Thailand, is a country in Southeast Asia, located at the centre of the Indochinese Peninsula, spanning , with a population of almost 70 million. The country is b ...
File:Northern pig-tailed macaque.JPG, Male adult in Khao Yai National Park, Thailand
File:Northern Pigtailed macaque at Koh Lanta Yai Monkey School.JPG, Female adult at a monkey school on Ko Lanta Yai
Ko Lanta Yai ( th, เกาะลันตาใหญ่) is an island in the Strait of Malacca off the west coast of Thailand, between the Phi Phi Islands and the mainland. It is administratively part of Krabi Province, most of which is on the ...
, Thailand
File:Macaca leonina at Gibbon WLS.jpg, Female adult at Hoollongapar Gibbon Sanctuary, India
India, officially the Republic of India (Hindi: ), is a country in South Asia. It is the seventh-largest country by area, the second-most populous country, and the most populous democracy in the world. Bounded by the Indian Ocean on the so ...
File:Monkey and Chicken - Don Khon - Laos.JPG, Pet juvenile grooming household chicken on Khong Island
Khong may refer to:
* Khong District, Laos, a district of Champasak Province
** Khong Island, in Laos
* Khong District, Nakhon Ratchasima, Thailand
* Khong, Iran (disambiguation), places in Iran
People with the surname
* Lawrence Khong (born 19 ...
, Laos
File:Northern pig-tailed macaque, Satchari National Park 03.jpg, Female by the tree trunk in her natural habitat
File:Macaca leonina, Northern pig-tailed macaque - Khao Yai National Park (11669396224).jpg, Female and an infant breastfeeding
References
External links
* ARKive
images and movies of the northern pigtail macaque ''(Macaca leonina)''
{{Taxonbar, from=Q913765
northern pig-tailed macaque
Mammals of Bangladesh
Mammals of India
Fauna of Tibet
Fauna of Yunnan
Primates of Southeast Asia
Articles containing video clips
northern pig-tailed macaque
northern pig-tailed macaque
Taxonomy articles created by Polbot