Geographic Range
Amazon weasels (
Mustela africana
), also known as tropical weasels, are found in South America. Early scientific records
regarding Amazon weasels inaccurately described their native range as Africa, which
has led to some confusion about their scientific name. This species is believed to
be native to Bolivia, Brazil, Colombia, Ecuador and Peru, but their range may also
include the Amazon Basin in Brazil.
- Biogeographic Regions
- neotropical
Habitat
Amazon weasels have been found in humid areas, mainly in forests close to the banks
of rivers. Along with a few other weasels, they have interdigital webbing, which may
allow them to move through the water with more ease and could explain why they live
so close to river banks.
- Habitat Regions
- tropical
- Terrestrial Biomes
- rainforest
Physical Description
Amazon weasels are small animals, the area from the tip of their nose to their tail
is less than 400 mm. Along with other weasels, Amazon weasels have short legs and
long bodies. They are very similar in appearance to
long-tailed weasels
. Both are brown with a pale underside and neither have markings on their faces. The
only visually apparent difference between them is the dark brown stripe that runs
down the stomach of Amazon weasels.
- Other Physical Features
- endothermic
- bilateral symmetry
Reproduction
There is currently no mating information available specific to Amazon weasels, however;
in general, female weasels have been known to mate with multiple males.
- Mating System
- polyandrous
Reproduction information on Amazon weasels is scarce. However, well-known weasel species,
such as
least weasels
, have a 34 to 37 day gestation period. If food is plentiful, the females can quickly
go into heat again after taking care of their first litter. The breeding season usually
occurs during the warmer months. Offspring tend to become independent by about the
fifth week.
- Key Reproductive Features
- gonochoric/gonochoristic/dioecious (sexes separate)
- sexual
- viviparous
In general, weasels do not spend much time caring for their offspring, providing only
milk and some protection from predators. When food is plentiful, females are more
focused on producing another litter than spending time with their previous litter.
When there is not an overabundance of food, females will hunt and bring back prey
for her offspring without help from the male.
- Parental Investment
- female parental care
Lifespan/Longevity
Currently there is no specific information available regarding the lifespan of Amazon
weasels because they are difficult to find and study. However, similar species, such
as least weasels (
Mustela nivalis
) and long-tailed weasels (
Mustela frenata
), have a maximum captive lifespan of 9 years and 8 years, respectively.
Behavior
Since Amazon weasels are hard to find and observe, there is no information available
about their behavior. Other weasels, such as
least weasels
, stand on their hind legs, which allows them to observe their surroundings while
foraging. Weasels also perform a dance behavior, which is said to distract prey so
they do not expect an attack.
- Key Behaviors
- terricolous
- diurnal
- motile
- territorial
Home Range
Currently there is no information available regarding the home range size of Amazon weasels.
Communication and Perception
There is currently very little information available regarding Amazon weasels since
they are not very well known. However, in general, species in family
Mustelidae
exhibit enlarged scent glands. These glands are the source of a thick secretion known
as musk. This scent is used for communication with other species and for defense purposes.
Weasels also mark their home range to establish their territory. Amazon weasels may
also have many different ways of communicating using vocalizations like other members
of the weasel family. Weasels make a hissing sound when they feel threatened and a
high-pitched sound when encountering a mate. Overall, weasels have a good sense of
vision, hearing and smell. Many species of weasels depend mostly on hearing while
hunting but also use their sense of smell. Weasels are also able to detect ultrasonic
vocalizations. Their enhanced olfactory capabilities may be somewhat based on their
muzzle construction. The placement of their eyes allows them to see in front and on
the sides. They are able to see fairly well during the day and at night.
- Other Communication Modes
- scent marks
- Perception Channels
- visual
- tactile
- acoustic
- ultrasound
- chemical
Food Habits
There is no information available on the foraging habits of Amazon weasels specifically,
but the foraging behaviors other weasels have been documented. Weasels have an elaborate
foraging process. They use all of their senses to find prey. Since their bodies are
close to the ground, they tend to search under everything. Weasels usually search
for prey for a short amount of time and rest before trying again. Weasels are able
to carry their prey, which most likely means they take it back to their den. Weasels
are considered small predators and they usually go after smaller prey including rabbits,
squirrels, rats and voles. Weasels are good hunters and are able to go after and successfully
take down prey bigger then themselves.
- Primary Diet
-
carnivore
- eats terrestrial vertebrates
- Animal Foods
- mammals
- Foraging Behavior
- stores or caches food
Predation
Weasels are generally hunted by larger predators such as
foxes
,
coyotes
,
owls
and hawks. However, predators that do kill weasels may not eat them because they
do not taste good.
Ecosystem Roles
There is not sufficient information for Amazon weasels specifically. However,
least weasels
are found in temperate farmlands and forests and have been known to consume large
amounts of small prey species in their territories. Least weasels can also carry skin
parasites such as
lice
,
ticks
and
mites
. Amazon weasels likely encounter these same skin parasites.
Economic Importance for Humans: Positive
Weasels kill many rodents and store the ones they don’t eat for later, this may help
control the pest population.
- Positive Impacts
- controls pest population
Economic Importance for Humans: Negative
Weasels sometimes raid birds' nests and eat the eggs and kill any adults that are
present. Birders may have a very negative reaction to this type of predation.
Conservation Status
Amazon weasels are listed as a 'Least Concern' species on the IUCN Redlist of Threatened
Species because scientists believe they still have a sizable population living in
the Amazonian forest. This weasel is also considered a
Data Deficient
species because scientists do not know much about them. It is not known whether this
species can handle anthropogenic disturbances in the environment.
Additional Links
Contributors
Ashley Mattice (author), Northern Michigan University, John Bruggink (editor), Northern Michigan University, Leila Siciliano Martina (editor), Texas State University.
- Neotropical
-
living in the southern part of the New World. In other words, Central and South America.
- native range
-
the area in which the animal is naturally found, the region in which it is endemic.
- tropical
-
the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.
- rainforest
-
rainforests, both temperate and tropical, are dominated by trees often forming a closed canopy with little light reaching the ground. Epiphytes and climbing plants are also abundant. Precipitation is typically not limiting, but may be somewhat seasonal.
- polyandrous
-
Referring to a mating system in which a female mates with several males during one breeding season (compare polygynous).
- sexual
-
reproduction that includes combining the genetic contribution of two individuals, a male and a female
- viviparous
-
reproduction in which fertilization and development take place within the female body and the developing embryo derives nourishment from the female.
- female parental care
-
parental care is carried out by females
- diurnal
-
- active during the day, 2. lasting for one day.
- motile
-
having the capacity to move from one place to another.
- 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
- 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
- ultrasound
-
uses sound above the range of human hearing for either navigation or communication or both
- 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"
- carnivore
-
an animal that mainly eats meat
- 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
Emmons, L., K. Helgen. 2012. " Mustela africana " (On-line). IUCN Redlist of Threatened Species. Accessed March 17, 2013 at www.iucnredlist.org .
Emmons, L. 1997. Neotropical Rainforest Mammals . Chicago, Illinois: University of Chicago Press.
Erlinge, S., M. Sandell. 1988. Coexistence of Stoat, Mustela erminea , and Weasel, M. nivalis : Social Dominance, Scent Communication, and Reciprocal Distribution. Nordic Society Oikos , 53: 242-246.
Feldhamer, G., L. Drickamer, S. Vessey, J. Merritt, C. Krajewski. 2007. Mammalogy . Baltimore, Maryland: The John Hopkins University Press.
Harding, L., F. Smith. 2009. Mustela or Vison? Evidence for the taxonomic status of the American mink and a distinct biogeographic radiation of American weasels. Molecular Phylogenetics and Evolution , 52: 632-642.
King, C., R. Powell. 2007. The Natural History of Weasels and Stoats . New York: Oxford University Press.
Mares, M., D. Schmidly. 1991. Latin American Mammalogy. History, Biodiversity, and Conservation . Publishing Division of the University: University of Oklahoma Press.
Tacutu, R., T. Craig, A. Budovsky, D. Wuttke, G. Lehmann, D. Taranukha, J. Costa, V. Fraifeld, J. de Magalhaes. 2013. " Mustela frenata " (On-line). AnAge: The Animal Ageing and Longevity Database. Accessed August 28, 2013 at http://genomics.senescence.info/species .
Tacutu, R., T. Craig, A. Budovsky, D. Wuttke, G. Lehmann, D. Taranukha, J. Costa, V. Fraifeld, J. de Magalhaes. 2013. " Mustela nivalis " (On-line). AnAge: The Animal Ageing and Longevity Database. Accessed August 28, 2013 at http://genomics.senescence.info/species .