Geographic Range
Macaya breast-spot frogs (
Eleutherodactylus thorectes
) live in the Neotropics. They live in a very restricted area of Haiti. They are endemic
to the Massif de la Hotte mountain range, on the peaks of Forman and Macaya. This
habitat is critical to their survival because of their incredibly small size and critically
endangered population.
- Biogeographic Regions
- neotropical
- Other Geographic Terms
- island endemic
Habitat
Macaya breast-spot frogs inhabit the subtropical climate of the Massif de la Hotte
mountain range. This habitat is referred to as a cloud forest, at an elevation of
1,700 to 2,340 m above sea level. This landscape consists of pines, ferns, shrubs,
and bamboo. They are primarily terrestrial and do not need large bodies of water in
which to lay their eggs. Macaya breast-spot frogs have such a specific habitat because
their survival depends on such specific conditions.
- Habitat Regions
- tropical
- terrestrial
- Terrestrial Biomes
- forest
Physical Description
Macaya breast-spot frogs are some of the smallest amphibians in the world, with an
average snout-vent length (SVL) of 12 to 15 mm. Their bodies are slimmer than their
heads, and they are longer in length than they are in width. Macaya breast-spot frogs
have brown and orange coloring to blend into their terrestrial surroundings. Since
they are critically endangered, there is not much information on their appearance
in the wild, but female and males seem to share most of the same characteristics.
Macaya breast-spot frogs have dark, spotted patterns on their heads, backs, and even
their breasts, which is where they get their nickname.
- Other Physical Features
- ectothermic
- homoiothermic
- bilateral symmetry
- Sexual Dimorphism
- sexes alike
Development
Macaya breast-spot frogs go through direct development. They hatch from eggs looking like a smaller version of adults and grow until they reach their mature size of about 12 to 15 mm. Sex is determined in a homomorphic process, which means that sex is determined in the early stages of development.
Most amphibians, including Macaya breast-spot frogs, can switch from one sex to another
by stimulation with sex steroids. The gender of these frogs can be changed in a relatively
short amount of time if environmental pressures call for either more females or males
to balance a population.
- Development - Life Cycle
- metamorphosis
- indeterminate growth
Reproduction
Macaya breast-spot frogs are polygynandrous, meaning both males and females have multiple
different mates within one lifetime. Females lay their eggs on the damp forest floor.
Researchers have discovered that Macaya breast-spot frogs are the smallest of all
oviparous (egg-laying) amphibians.
- Mating System
- polygynandrous (promiscuous)
There is barely any information on the mating habits of Macaya breast-spot frogs.
It is extremely hard to observe them in the wild because of their critically endangered
status and their very small size. Upon birth, young are immediately independent.
- Key Reproductive Features
- seasonal breeding
- gonochoric/gonochoristic/dioecious (sexes separate)
- sexual
Macaya breast-spot frogs do not exhibit any parental investment. After she lays her
eggs, mothers will leave and not return. Once eggs hatch, offspring separate from
their siblings and go off to develop into adults and mate on their own.
- Parental Investment
- no parental involvement
- pre-hatching/birth
Lifespan/Longevity
Not much is known about the lifespan of Macaya breast-spot frogs, since they are very
hard to track and observe over long periods of time. Macaya breast-spot frogs are
critically endangered, primarily from habitat loss. This habitat loss is due to the
pressure on Haiti to produce charcoal, lumber, and agricultural land. Statistical
data from 2016 stated that there would be an 80% decline in the Macaya breast-spot
frog population in the next 10 years.
Behavior
Macaya breast-spot frogs are a solitary species. They have long, muscular legs, which
help them move through their environment. Macaya breast-spot frogs can jump almost
20 times their own body length. At night they forage, move to safer grounds, or lay
eggs.
- Key Behaviors
- terricolous
- saltatorial
- nocturnal
- motile
- sedentary
- solitary
Home Range
Macaya breast-spot frogs live in the Massif de la Hotte mountain range in Haiti. Since
they are so small, they do not cover a large amount of land in their lifetimes. From
what researchers say, Macaya breast-spot frogs are able to live in a range with other
frogs of the same species.
Communication and Perception
Macaya breast-spot frogs primarily use acoustic communication, but this is mostly
restricted to mating calls. These mating calls can only be produced by males, and
resemble a soft clucking produced at a fast frequency.
- Communication Channels
- acoustic
- Other Communication Modes
- duets
- Perception Channels
- visual
Food Habits
The diet of Macaya breast-spot frogs mainly consists of small insects that also reside in the Massif de la Hotte region of Haiti. They forage nocturnally and do not need very feed often.
- Primary Diet
- carnivore
- Animal Foods
- insects
Predation
The extremely small size of Macaya breast-spot frogs is their biggest anti-predator
adaptation. They are able to blend into surrounding terrain and not be seen by predators.
During the day, Macaya breast-spot frogs use their surroundings to hide on land and
rest while diurnal predators.
- Anti-predator Adaptations
- cryptic
Ecosystem Roles
The effect that Macaya breast-spot frogs play on their environment is hard to measure. Since The Massif de la Hotte region in Haiti is threatened by coal mining and slash and burn agriculture, their habitat is already under stress and change. Without a stable environment, differences in the ecosystem made by one small species cannot be determined, due to the larger scale changes occurring simultaneously.
- possibly parasitic nematodes
Economic Importance for Humans: Positive
Macaya breast-spot frogs play a small role in the immense diversity of the Massif
de la Hotte mountain range. They bring in eco-tourists from all over the world looking
for an experience in the natural habitat. Now that this habitat is being destroyed,
tourism is declining and creating an economic disparity for the companies and businesses
that rely on revenue obtained from eco-tourists.
- Positive Impacts
- ecotourism
Economic Importance for Humans: Negative
There are no known negative economic effects of Macaya breast-spot frogs.
Conservation Status
Macaya breast-spot frogs are a critically endangered species according to the IUCN Red List. Their population has not been counted since some time between 1980 and 1990. However, there have been predictions of massive decline in the remaining amphibian populations in the Massif de la Hotte mountain region. Scientists think that more than 80% of the Macaya breast-spot frog has become extinct since 1990.
Other Comments
There is not much information on Macaya breast-spot frogs because they are extremely hard to observe in the wild. Most of the information known about them is from capture, observation, and research in lab conditions.
Additional Links
Contributors
Anna Waddell (author), Colorado State University, Brooke Berger (editor), Colorado State University, Galen Burrell (editor), Special Projects.
- 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.
- island endemic
-
animals that live only on an island or set of islands.
- tropical
-
the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.
- terrestrial
-
Living on the ground.
- forest
-
forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.
- ectothermic
-
animals which must use heat acquired from the environment and behavioral adaptations to regulate body temperature
- 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.
- metamorphosis
-
A large change in the shape or structure of an animal that happens as the animal grows. In insects, "incomplete metamorphosis" is when young animals are similar to adults and change gradually into the adult form, and "complete metamorphosis" is when there is a profound change between larval and adult forms. Butterflies have complete metamorphosis, grasshoppers have incomplete metamorphosis.
- indeterminate growth
-
Animals with indeterminate growth continue to grow throughout their lives.
- polygynandrous
-
the kind of polygamy in which a female pairs with several males, each of which also pairs with several different females.
- 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
- saltatorial
-
specialized for leaping or bounding locomotion; jumps or hops.
- nocturnal
-
active during the night
- motile
-
having the capacity to move from one place to another.
- sedentary
-
remains in the same area
- solitary
-
lives alone
- acoustic
-
uses sound to communicate
- duets
-
to jointly display, usually with sounds in a highly coordinated fashion, at the same time as one other individual of the same species, often a mate
- visual
-
uses sight to communicate
- cryptic
-
having markings, coloration, shapes, or other features that cause an animal to be camouflaged in its natural environment; being difficult to see or otherwise detect.
- ecotourism
-
humans benefit economically by promoting tourism that focuses on the appreciation of natural areas or animals. Ecotourism implies that there are existing programs that profit from the appreciation of natural areas or animals.
- carnivore
-
an animal that mainly eats meat
- insectivore
-
An animal that eats mainly insects or spiders.
References
Green, D., S. Sessions. 1991. The influence of life history on karyotypic evolution in frogs . San Diego, California: Academic Press INC.. Accessed February 09, 2020 at https://books.google.com/books?The+influence+of+life+history+on+karyotypic+evolution+in+frogs .
Hedges, S., R. Thomas, R. Powell. 2010. "Eleutherodactylus thorectes" (On-line). Red List. Accessed February 09, 2020 at https://www.iucnredlist.org/species/57004/11563733 .
Hedges, S., R. Powell. 1998. Eleutherodactylus thorectes. Catalogue of American Amphibians and Reptiles (CAAR) , 677: 1-2.
Hedges, S. 1988. A new diminutive frog from Hispaniola (Leptodactylidae: Eleutherodactylus). Copeia , Issue 3: 636-641. Accessed March 01, 2020 at http://search.proquest.com/docview/15580697/ .
Moore, R. 2008. "Eleutherodactylus thorectes" (On-line). Accessed February 09, 2020 at https://www.iucnredlist.org/species/57004/11563733 .
Rittmeyer, E., A. Allison, M. Gründler, D. Thompson, C. Austin, W. Etges. 2012. Ecological Guild Evolution and the Discovery of the World's Smallest Vertebrate. PLoS ONE , Volume 7(1): all. Accessed March 01, 2020 at https://doi.org/10.1371/journal.pone.0029797 .
Sartore, J. 2020. "Photo: Macaya breast-spot frog (Eleutherodactylus thorectes) at the Philadelphia Zoo. This species is found in Haiti and is critically endangered. ANI101-00268" (On-line). Joel Sartore. Accessed February 09, 2020 at https://www.joelsartore.com/ani101-00268/ .
Smith, R., W. Sutherland. 2014. Amphibian Conservation: Global evidence for the effects of interventions . University of Cambridge: Pelagic Publishing. Accessed February 09, 2020 at https://books.google.com/books?id=4Ep_BAAAQBAJ&printsec=frontcover&dq=Amphibian+Conservation:+Global+evidence+for+the+effects+of+interventions .
Darrel Frost and The American Museum of Natural History. 2020. "Eleutherodactylus thorectes Hedges, 1988" (On-line). American Museum of Natural History. Accessed February 09, 2020 at http://research.amnh.org/vz/herpetology/amphibia/Amphibia/Anura/Brachycephaloidea/Eleutherodactylidae/Eleutherodactylinae/Eleutherodactylus/Eleutherodactylus-thorectes .
2010. "Taxonomy browser (Eleutherodactylus thorectes)" (On-line). NCBI. Accessed February 09, 2020 at https://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?id=448498 .