The common coquí or coquí (''Eleutherodactylus coqui'') is a species of

frog A frog is any member of a diverse and largely Carnivore, carnivorous group of short-bodied, tailless amphibians composing the order (biology), order Anura (ανοὐρά, literally ''without tail'' in Ancient Greek). The oldest fossil "proto-f ...

endemic to

Puerto Rico Puerto Rico (; abbreviated PR; tnq, Boriken, ''Borinquen''), officially the Commonwealth of Puerto Rico ( es, link=yes, Estado Libre Asociado de Puerto Rico, lit=Free Associated State of Puerto Rico), is a Caribbean island and Unincorporated ...

belonging to the family

Eleutherodactylidae The Eleutherodactylidae are a family of direct-developing frogs native to northern South America, the Caribbean, and southernmost North America. They are sometimes known under the common name rain frogs. Formerly the subfamily Eleutherodactylina ...

. The species is named for the loud call the males make at night. This sound serves two purposes. "CO" serves to repel other males and establish territory while the "KEE" serves to attract females. Since the auditory systems of males and females respond preferentially to different notes of the male call, this is an example of a sex difference in a sensory system. The common coquí is a very important aspect of

Puerto Rican culture The culture of Puerto Rico is the result of a number of international and indigenous influences, both past and present. Modern cultural manifestations showcase the island's rich history and help to create an identity which is uniquely Puerto Rica ...

, and it has become an unofficial territorial symbol of Puerto Rico.

Taxonomy

The common coquí was described as a species new to science by Richard Thomas in 1966. It belongs to the genus ''

Eleutherodactylus ''Eleutherodactylus'' is a genus of frogs in the family Eleutherodactylidae.Hedges, S. B., W. E. Duellman, and M. P. Heinicke . 2008. New World direct-developing frogs (Anura: Terrarana): molecular phylogeny, classification, biogeography, and co ...

'' which in Greek means ''free toes''. This family is also known as the "robber" or "thief" frogs. This genus contains 185 species, which are found in the

Southern United States The Southern United States (sometimes Dixie, also referred to as the Southern States, the American South, the Southland, or simply the South) is a geographic and cultural region of the United States of America. It is between the Atlantic Ocean ...

Central America Central America ( es, América Central or ) is a subregion of the Americas. Its boundaries are defined as bordering the United States to the north, Colombia to the south, the Caribbean Sea to the east, and the Pacific Ocean to the west. ...

South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere at the northern tip of the continent. It can also be described as the southe ...

, and the

Caribbean The Caribbean (, ) ( es, El Caribe; french: la Caraïbe; ht, Karayib; nl, De Caraïben) is a region of the Americas that consists of the Caribbean Sea, its islands (some surrounded by the Caribbean Sea and some bordering both the Caribbean Se ...

. It is part of the Order Anura, which includes all frogs and toads. The scientific name of the Common coquí, Eleutherodactylus coqui, was first described by Spanish naturalist José Félix de Arroyo de la Cuesta in 1875 (Arroyo de la Cuesta, 1875). The genus Eleutherodactylus, of which the Common coquí is a member, is the largest genus of frogs in the world, with over 700 known species. The Common coquí is closely related to other members of the Eleutherodactylidae family, including the Eleutherodactylus jasperi and the Eleutherodactylus portoricensis. These species are all native to Puerto Rico and are distinguished from each other by their physical characteristics and vocalizations (Joglar and López, 1997). This taxonomic classification reflects the evolutionary relationships between the Common coquí and other species within the animal kingdom.

Description

Appearance and Lifespan

Full-grown male coquís measure, from

snout A snout is the protruding portion of an animal's face, consisting of its nose, mouth, and jaw. In many animals, the structure is called a muzzle, rostrum, or proboscis. The wet furless surface around the nostrils of the nose of many mammals is c ...

to vent, from 30 to 37 mm, with an average of 34 mm, while full-grown females measure from 36 to 52 mm, with an average of 41 mm. The location of the frog also effects the size, for example the higher the elevation, the larger the coquis become. The size differences between sexes are a result of additional energy consumption related to breeding behavior by males.Henderson and Schwartz, p. 42. Coquís are muddy-brown in

mottle Mottle is a pattern of irregular marks, spots, streaks, blotches or patches of different shades or colours. It is commonly used to describe the surface of plants or the skin of animals. In plants, mottling usually consists of yellowish spots o ...

d coloration on the top with rust-tan flanks and a light-gray

belly Belly may refer to: Anatomy * The abdomen, the part of the body between the pelvis and the thorax; or the stomach ** A beer belly, an overhang of fat above the waist, presumed to be caused by regular beer drinking ** Belly dance * The fleshy, cen ...

. As

tree frog A tree frog (or treefrog) is any species of frog that spends a major portion of its lifespan in trees, known as an arboreal state. Several lineages of frogs among the Neobatrachia have given rise to treefrogs, although they are not closely relat ...

s, Coquís possess sticky pads on the tips of their toes which help them adhere to moistened or slippery surfaces They do not possess

webbed feet The webbed foot is a specialized limb with interdigital membranes (webbings) that aids in aquatic locomotion, present in a variety of tetrapod vertebrates. This adaptation is primarily found in semiaquatic species, and has convergently evolved m ...

and are not adapted to swimming. The known lifespan of the common coquí is up to 6 years in the wild, but the majority of adults do not live past one year. It is generally thought that the species has a relatively short lifespan, with most individuals living for less than a year. In a study of the population dynamics of the Common coquí, researchers found that the species has a high mortality rate, with only a small proportion of individuals surviving to reach adulthood. This high mortality is likely due to a variety of factors, including predation, disease, and competition for resources. Overall, the Common coquí is thought to have a short lifespan, with most individuals living for less than a year. This is due to a combination of factors that affect the species' survival in its natural environment.

Behavior

The common coquis are nocturnal and their behavior is influenced by the surrounding environment, specifically the moisture levels. When humidity levels rise at night they emerge and begin climbing to their homes in the canopy. As these humidity levels decrease they move back down to lower levels where the humidity is higher. The younger coqui populations live in the understory on leaves during the drier periods. The leaves are particularly common with this population because they provide protection from invaders. As they grow into adulthood, the coquis journey up to the canopy and begin the process stated above. A comparative behavioral study between frog species identified possible explanation for jump and hydration level correlations. The paper, "Water loss, cutaneous resistance, and effects of dehydration on locomotion of Eleutherodactylus frogs," examines the effects of water loss and dehydration on two species of neotropical frogs, the common coquí and the cave coquí (Eleutherodactylus cooki). The researchers found that jumping performance declined with an increase in water loss and a longer duration of exposure to dehydrating conditions. The common coquí, which occupies a wider range of habitats, including dry forests, had a slightly higher rate of water loss and lower cutaneous resistance than the cave coquí. However, these differences were not significant enough to explain the different geographic distributions of the two species. The study suggests that behavioral adaptations, rather than physiological differences, may play a role in the common coquí's ability to survive in drier habitats.

Habitat

Native Disruption

Common coquís are native to the islands of Puerto Rico,

Vieques Vieques (; ), officially Isla de Vieques, is an island and municipality of Puerto Rico, in the northeastern Caribbean, part of an island grouping sometimes known as the Spanish Virgin Islands. Vieques is part of the Commonwealth of Puerto Rico, ...

and Culebra, where they are widespread and abundant; the only notable exception occurs in

Puerto Rican dry forests The Puerto Rican dry forests are a tropical dry forest ecoregion located in southwestern and eastern Puerto Rico and on the offshore islands. They cover an area of . These forests grow in areas receiving less than of rain annually. Many of the ...

, where the species is rarer. The common coquí is the most abundant frog in Puerto Rico, with densities estimated at 20,000 individuals/ha. Densities fluctuate depending on the season and habitat. Generally, densities are higher during the latter half of the wet season and decrease during the dry season. The species is considered a habitat generalist, occurring in a wide range of habitats, including mesic broadleaf forests, mountains, and urban areas, found in

bromeliad The Bromeliaceae (the bromeliads) are a family of monocot flowering plants of about 80 genera and 3700 known species, native mainly to the tropical Americas, with several species found in the American subtropics and one in tropical west Africa, ...

s, tree holes, and under trunks, rocks or trash. Since the species does not require bodies of water to reproduce, they can be found on most altitudes, provided sufficient moisture is available. In Puerto Rico, they are found from sea level to a maximum of . Adults generally tend to be found at higher altitudes than juveniles. The common coquís are often found in cohabitation with humans. Because of their unrestricted habitat use, ''E. coquí'' can commonly be found in homes and parks. ''E. coquí'' are found in natural habitats including the human mountain forest at elevations less than 1,200 meters and in the dry forest. They are found specifically within the under story of forests at all elevations up to the canopy.

Distribution as an Invasive Species

The species has been introduced to

Colombia Colombia (, ; ), officially the Republic of Colombia, is a country in South America with insular regions in North America—near Nicaragua's Caribbean coast—as well as in the Pacific Ocean. The Colombian mainland is bordered by the Car ...

Hawaii Hawaii ( ; haw, Hawaii or ) is a state in the Western United States, located in the Pacific Ocean about from the U.S. mainland. It is the only U.S. state outside North America, the only state that is an archipelago, and the only stat ...

in the

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territorie ...

, and the

Virgin Islands The Virgin Islands ( es, Islas Vírgenes) are an archipelago in the Caribbean Sea. They are geologically and biogeographically the easternmost part of the Greater Antilles, the northern islands belonging to the Puerto Rico Trench and St. Croix ...

. It has become a densely populated

invasive species An invasive species otherwise known as an alien is an introduced organism that becomes overpopulated and harms its new environment. Although most introduced species are neutral or beneficial with respect to other species, invasive species ad ...

in the Hawaiian Islands, where it was accidentally introduced in the late 1980s, most likely as a stowaway on potted plants, and quickly established itself on all four major islands. It is now considered a pest species by the State of Hawaii, and is on a list of 100 of the world's worst

invasive alien species An invasive species otherwise known as an alien is an introduced species, introduced organism that becomes overpopulated and harms its new environment. Although most introduced species are neutral or beneficial with respect to other species, i ...

. As an invasive species, it can reach up to 91,000 individuals/ha, almost 5 times its maximum density in its native Puerto Rico. Higher densities in its invaded range are likely bolstered by a release from native predators, lack of interspecific competitors, and abundant food availability. In Hawaii, they have been found at a maximum of above sea level. They were previously introduced in the

Dominican Republic The Dominican Republic ( ; es, República Dominicana, ) is a country located on the island of Hispaniola in the Greater Antilles archipelago of the Caribbean region. It occupies the eastern five-eighths of the island, which it shares wit ...

and to

Louisiana Louisiana , group=pronunciation (French: ''La Louisiane'') is a state in the Deep South and South Central regions of the United States. It is the 20th-smallest by area and the 25th most populous of the 50 U.S. states. Louisiana is borde ...

and

Florida Florida is a state located in the Southeastern region of the United States. Florida is bordered to the west by the Gulf of Mexico, to the northwest by Alabama, to the north by Georgia, to the east by the Bahamas and Atlantic Ocean, and to ...

, but these populations have now been eradicated. Common coquís in areas where their density exceeds 51,000/ha could consume over 300,000 invertebrates per night. Because of their large populations, Hawaii worries about both economic and ecological impacts. The common coquí currently costs this state nearly 3 million dollars a year. Its spread has been commonly through the nursery trade, and as a result many people are reluctant to buy plants from nurseries that might be infected. Those began to perform quarantines and de-infestations in order to improve their prospects. Coquis also affect real estate values in residential neighborhoods, as many refrain from buying houses where their sleep would be disturbed by the up to 73 dB call of the common coquí.

Invasive Management Strategies

Invasive management practices against the Common coquí frog aim to control and reduce the population of this species in areas where it has been introduced, such as Hawaii. Preventative measures include banning the intentional transport of frogs, as well as the implementation of hot-water shower treatments on ornamental plants to kill coquí eggs, subadults, and adults. This can reduce the potential spread of the species through the trade of plants. Physical control methods, such as hand-capture, can be effective for small populations of Common coquí frogs. Chemical control methods, such as the use of caffeine and water solutions, are also being tested for their efficacy in controlling the species on a larger scale. Citric acid has also been suggested as a potential control method, although its efficacy has not been demonstrated. Overall, a variety of management practices are being explored and implemented in order to control and reduce the population of Common coquí frogs in invaded areas.

Diet

The common coquí is a generalist nocturnal

predator Predation is a biological interaction where one organism, the predator, kills and eats another organism, its prey. It is one of a family of common feeding behaviours that includes parasitism and micropredation (which usually do not kill th ...

, which can consume, as a population, 114,000 invertebrates each night per hectare. Diets vary depending on age and size, but are primarily composed of

arthropod Arthropods (, (gen. ποδός)) are invertebrate animals with an exoskeleton, a Segmentation (biology), segmented body, and paired jointed appendages. Arthropods form the phylum Arthropoda. They are distinguished by their jointed limbs and Arth ...

s. Juveniles consume smaller prey, such as

ant Ants are eusocial insects of the family Formicidae and, along with the related wasps and bees, belong to the order Hymenoptera. Ants evolved from vespoid wasp ancestors in the Cretaceous period. More than 13,800 of an estimated total of 22 ...

s, while adults consume more varied diets that include

spider Spiders ( order Araneae) are air-breathing arthropods that have eight legs, chelicerae with fangs generally able to inject venom, and spinnerets that extrude silk. They are the largest order of arachnids and rank seventh in total species ...

moth Moths are a paraphyletic group of insects that includes all members of the order Lepidoptera that are not butterflies, with moths making up the vast majority of the order. There are thought to be approximately 160,000 species of moth, many of w ...

crickets Crickets are orthopteran insects which are related to bush crickets, and, more distantly, to grasshoppers. In older literature, such as Imms,Imms AD, rev. Richards OW & Davies RG (1970) ''A General Textbook of Entomology'' 9th Ed. Methuen 8 ...

snail A snail is, in loose terms, a shelled gastropod. The name is most often applied to land snails, terrestrial pulmonate gastropod molluscs. However, the common name ''snail'' is also used for most of the members of the molluscan class Gastro ...

s, and small

s. The frogs are opportunistic sit-and-wait predators, and will forage on any abundant prey items. Males will occasionally consume eggs from their own clutch, likely to provide supplemental nourishment while guarding their nests. Calling males eat less prey than quiet males, which consume most of their food by midnight, while calling males had eaten only 18% of their food by the same hour.

Reproduction

Common coquís reproduce over the entire year, but breeding activity peaks around the

wet season The wet season (sometimes called the Rainy season) is the time of year when most of a region's average annual rainfall occurs. It is the time of year where the majority of a country's or region's annual precipitation occurs. Generally, the sea ...

. Females usually lay between 16 and 40 eggs, four to six times each year, at about eight-week intervals. Eggs are guarded from predators—other common coquís and '' Subulina'' snails—by the males. The

gestation period In mammals, pregnancy is the period of reproduction during which a female carries one or more live offspring from implantation in the uterus through gestation. It begins when a fertilized zygote implants in the female's uterus, and ends once it ...

of coquís is from 17 to 26 days. The maturation period, the time from egg to reproductive coquí, is around eight months. Unlike most frogs, which lay their eggs in water, coquís lay their eggs on palm tree leaves or other terrestrial plants. Abandoned bird nests are also used as nests by ''E. coqui''. The

bananaquit The bananaquit (''Coereba flaveola'') is a species of passerine bird in the tanager family Thraupidae. Before the development of molecular genetics in the 21st century, its relationship to other species was uncertain and it was either placed with ...

Puerto Rican bullfinch The Puerto Rican bullfinch (''Melopyrrha portoricensis'') is a small bullfinch tanager endemic to the archipelago of Puerto Rico. The species can be commonly found in heavy forests throughout Puerto Rico, except on the easternmost tip of the isl ...

and

Puerto Rican tody The Puerto Rican tody (''Todus mexicanus'') is a bird endemic to Puerto Rico. It is locally known in Spanish as "San Pedrito" ("little Saint Peter") and "medio peso" ("half-dollar bird"). Taxonomy Todies are the closest relative to the motmots ...

share nests with the coquí. This method of reproduction allows the coquí to live in forests, mountains and other

habitat In ecology, the term habitat summarises the array of resources, physical and biotic factors that are present in an area, such as to support the survival and reproduction of a particular species. A species habitat can be seen as the physical ...

s without direct dependency on water. Since eggs are laid on land, coquís bypass the

tadpole A tadpole is the larval stage in the biological life cycle of an amphibian. Most tadpoles are fully aquatic, though some species of amphibians have tadpoles that are terrestrial. Tadpoles have some fish-like features that may not be found i ...

stage, proceeding to develop limbs within their eggs, rather than going through a

metamorphosis Metamorphosis is a biological process by which an animal physically develops including birth or hatching, involving a conspicuous and relatively abrupt change in the animal's body structure through cell growth and differentiation. Some inse ...

as a larva in water. Thus, a fully independent froglet emerges from the egg, with a small tail that is lost shortly after. This stage of direct development has allowed the coqui to become a successful terrestrial colonizer in tropical areas. Eggs hatch within eight weeks and reach reproductive maturity within one year. The common coqui releases their young from the egg using an egg tooth that the genus ''Eleutherodactylus'' forms. Both males and females fight off intruders from their nests by jumping, chasing and sometimes biting. The males are the primary caretakers of the eggs. They offer protection and moist environments through skin contact. They will leave during very dry periods in order to collect more moisture for their offspring. Males begin their

mating call A mating call is the auditory signal used by animals to attract mates. It can occur in males or females, but literature is abundantly favored toward researching mating calls in females. In addition, mating calls are often the subject of mate choic ...

s by perching above ground level.Listen to this species's mating cal
here
The coqui's call (or ''canto'' in Spanish) is used both as a way of attracting a mate and to establish a territorial boundary. A coqui may enter another's territory and challenge the incumbent by starting his call, at which point they may engage in a sort of singing duel (which can last for several minutes). The first to falter in keeping up with the cadence is considered the loser and leaves the area without resorting to physical violence. This behavior is consistent across different species (which have distinctive calls), so it is possible to hear a duel where one coqui sings "COQUI" and another "COQUIRIQUI".

References

Bibliography

External links

Hawaiian Ecosystems at Risk project (HEAR): ''Eleutherodactylus coqui''

Control of Coqui Frog in Hawaii

Children Story About Coqui; El Coqui De Madagascar
{{DEFAULTSORT:Common Coqui Amphibians described in 1966 Eleutherodactylus Coqui, Common Coqui, Common