Gold Arrow Poison Frog

Dendrobates auratus can be identified by their calligraphic brillant green markings on a black background on their dorsal side (Caldwell and Summers 2003). Ventrally, they are marbled or spotted with yellow, blue, or green on dark background (Guyer and Donnelly 2005). Among populations there are variation in both hue (ranging from white to blue-green) and pattern (from thick stripes to dots) (Caldwell and Summers 2003). Dendrobates auratus has a smooth upper surface with a head that is relatively long. The snout truncates to slightly rounded (Savage 2002). Dendrobates auratus is the largest poison-dart frog in Costa Rica, with adult females ranging from 27.0-42.0 mm and adult males ranging from 25.0-39.5 mm (Leenders 2001).A Spanish-language species account can be found at the website of Instituto Nacional de Biodiversidad (INBio) (http://darnis.inbio.ac.cr/FMPro?-DB=UBIpub.fp3&-lay=WebAll&-Format=/ubi/detail.html&-Op=bw&id=4396&-Find).This species was featured as News of the Week on 15 February 2016:Birds and mammals are well-known for their behavioral flexibility and learning aptitudes, but these traits are not as well-characterized in amphibians. Liu et al. (2016) investigated these traits in the poison frog Dendrobates auratus, a species with complex reproductive strategies that may favor highly flexible forms of learning. Experiments on serial reversal learning using a two-sided maze with distal visual cues revealed that the frogs could learn to identify the correct exit. Probe trials in which visual cues were switched demonstrated that the frogs relied on these cues. Serial reversals demonstrated that the frogs learned to learn more rapidly across trials, employing rule-based strategies to solve the maze with increasing rapidity, thus demonstrating high levels of behavioral flexibility and learning ability in an amphibian (written by Kyle Summers).This species was featured as News of the Week on 3 June 2019:Amphibian genomes can be extraordinarily large, making it difficult to connect the genotype to the phenotype using large-scale genome-sequencing methods. One approach to this challenge is to take a transcriptomic approach, focusing on differential gene expression across different phenotypes in specific tissues. Stuckert et al. (2019) take this approach to investigate differential gene expression across distinct color pattern morphs in the green and black poison frog (Dendrobates auratus). These morphs vary in both background color (brown to black) and foreground (green to blue). They sequenced transcripts from skin tissue taken from tadpoles just reaching metamorphosis, an active period for pigment deposition and skin color development. A number of candidate color pattern genes were found to be differentially expressed between morphs, including genes involved in melanin production and melanosome development in basal skin layers (e.g. the tyrosinase-related protein 1, which catalyzes several key steps in melanogenesis, and affects dark coloration in a variety of vertebrates), genes involved in the development of iridophores (middle layer organelles containing reflective structures associated with blue-green coloration), and genes involved in yellow, orange and red pigment production in xanthophores (e.g. genes in pteridine pigment production pathways). These results will begin to provide insights into the genetic underpinnings of color variation in the brightly colored Neotropical poison frogs (Written by Kyle Summers).

This species can be found on the Caribbean slopes from southern Nicaragua to extreme eastern Panama, and on the Pacific slopes from the Osa Peninsula, Costa Rica to Colombia (Guyer and Donnelly 2005). It lives in lowlands, primarily rainforest (Caldwell and Summers 2003). It is a shy species, found deep in the forest interior (Leenders 2001).

This species is not threatened (Caldwell and Summers 2003).

These frogs forage during the day (Guyer and Donnelly 2005). They move by a series of hops, stopping briefly and hopping again when disturbed. They are excellent climbers with individuals climbing to 45 m above the ground (Savage 2002). Males are territorial at high population densities but may not be at low populaton densities (Caldwell and Summers 2003). The male call is a high-pitched, insect-like buzz sounding like "cheez-cheez-cheez" (Leenders 2001). The call averages 3.5 kHz in frequency, and can last from two to four seconds followed by a five-second pause (Savage 2002). Males can mate with many females and care for offspring of different females simultaneously (Caldwell and Summers 2003). Females court the males and wrestle other females and chase them from their territories (Savage 2002). This behavior increases male reproductive success but puts survival success of offspring in jeopardy, since females do not defend their territories (Caldwell and Summers 2003). A single male can mate with up to six females (Savage 2002). After being selected by the females, the males then lead the females to the nest site made from leaf litter and the females lay four to six eggs there (Guyer and Donnelly 2005). The male visits the eggs periodically over the incubation period to shed water, remove fungus, and rotate the eggs. After the eggs hatch, the tadpoles crawl up on the male's back (Savage 2002). The male then transports the tadpoles to small pools of water, usually found in tree holes (Caldwell and Summers 2003). If some eggs hatch earlier than others, the tadpoles that are born first may practice cannibalism by eating the smaller tadpoles. The tadpoles' diet consist of algae, detritus, protozoans, insect larvae, and each other (Leenders 2001). Tadpoles are moderate-sized and can reach 30 mm (Savage, 2002). The adults' diets consist mainly of tiny ants and mites but they also prey on beetles, flies, and springtails (Caldwell and Summers 2003). They are known to have a life-span of eight years in captivity but it is much lower in the wild (Leenders 2001).

This species is popular in the pet trade due to its bright colors (Leenders 2001).

Maximum longevity: 20.5 years (captivity) Observations: Record longevity of this species belongs to a 20.5-years-of-age specimen at Woodland Park Zoo in Seattle (http://www.zoo.org/).

Longevity is not well-known.

Average lifespan
Status: captivity: 8.3 years.

Dendrobates auratus avoids predation through their aposematic coloration and extremely toxic skin secretions.

Anti-predator Adaptations: aposematic

Dendrobates auratus has many color variants. Most of them are black and either green or light blue, with the black in bands or spots. The Hawaiian frogs are metallic green or brownish-black. The adults are approximately 4 cm long. As is true of most frogs, adults have a fused head and trunk with no tail. Tadpoles use gills to breathe, unlike the adults, which breathe through lungs. Tadpoles also lack legs and have tails, which is appropriate for their watery habitat. Another important physical characteristic of D. auratus is the poison glands located throughout the surface of their body. Their bright colors are believed to encourage predators with color vision to avoid the frogs. The boldly contrasting patterns may be aposematic to predators that lack color vision, although this has not been proven. Approximately 90 alkaloids have been identified from all species of dendrobatids <.. (Myers & Daly, 1976)

Average length: 4 cm.

Other Physical Features: ectothermic ; heterothermic ; bilateral symmetry ; polymorphic ; poisonous

Sexual Dimorphism: sexes alike

Dendrobates auratus adults are found on the floor of rain forests. They prefer locations near small streams or pools. The tadpoles live in these small pools or streams. Where the frogs live in the heavily populated areas of Hawaii, the eggs are often deposited in broken beer bottles or old cans instead of the usual puddle. (Whitfield 1984)

Habitat Regions: tropical ; terrestrial

Terrestrial Biomes: rainforest

Aquatic Biomes: rivers and streams; temporary pools

Dendrobates auratus can be found in Central and South America, from Nicaragua and Costa Rica to southeastern Brazil and Bolivia. They were also introduced in Hawaii by humans, and have flourished there. ( http://ecology.miningco.com/library/weekly/aa012598.htm)

Biogeographic Regions: neotropical (Native ); oceanic islands (Introduced )

Dendrobates auratus individuals prey on small invertebrates. Most notably, these frogs eat ants that have high quantities of alkaloids in their tissues. The frogs can sequester those alkaloids in their skin, which is what makes them poisonous. Dendrobates auratus individuals kept in captivity and fed a diet of insects without alkaloids will lose their toxicity. These frogs capture their prey by using their sticky, retractible tongues as well as their excellent eyesight. (Obst 1988)

Animal Foods: insects; terrestrial non-insect arthropods

Primary Diet: carnivore (Insectivore , Eats non-insect arthropods)

Poison dart frogs are important predators of small invertebrates.

Dendrobates auratus have long been used by local peoples to provide poison for their weapons. Currently the possibility of various medicines being derived from the frogs is being explored. Pharmaceutical companies are investigating the possibilities of a painkiller, ABT-594, being developd from a compound called epibatidine, which is found in D. auratus. The drug has the potential to be approximately 200 times more potent than morphine in blocking pain in animals, yet shows no sign of side effects of addiction. Since there have been over 80 alkaloids discovered from the 20 species of dendrobatids, there is much more research being conducted, especially on the effects of the alkaloids on neurological and muscular disorders. These frogs are also bred in captivity and sold extensively in the exotic pet trade. People enjoy them as pets because they are so colorful, and although they provide a challenge to owners, they do fairly well in captivity. (Merickel 1998)

Positive Impacts: pet trade ; body parts are source of valuable material; source of medicine or drug ; research and education

There are no negative impacts of these frogs on humans, although the skin of these frogs is highly toxic and unprotected contact can be dangerous.

Negative Impacts: injures humans (poisonous )

Development - Life Cycle: metamorphosis

Dendrobates auratus are not currently listed as in danger. However, with the destruction of their habitat, tropical rain forests, it is now likely that in a short time they will be in trouble. In fact, it is speculated that members of the genus Dendrobates will be the first poison dart frogs to be put on the endanged list of a major conservation organization such as CITES or ESA.

( http://ecology.miningco.com/library/weekly/aa012598.htm)

US Federal List: no special status

CITES: appendix ii

IUCN Red List of Threatened Species: least concern

Little is known of communication in this species. Males use vocalizations to attract females for mating and advertise territories. It is also possible that visual displays, tactile stimuli, and chemical cues are involved. They use their excellent vision to capture prey.

Communication Channels: visual ; tactile ; acoustic ; chemical

Perception Channels: visual ; tactile ; acoustic ; vibrations ; chemical

Poison dart frogs appear to be highly adaptabe, since they do well in aquariums, and they were successfully introduced in Hawaii. They make excellent pets for decoration, although they can't be touched because of their toxicity. They are colorful and lively, as well as being relatively easy to maintain. They do, however, tend to lose their toxicity when kept in captivity, possibly because of the loss of wild food sources. With the rain forests disappearing every day, the danger to the frogs is evident. Although scientists are studying their toxins and the possibility of obtaining medicines from D. auratus, the time is fast approaching when it may not be possible to take advantage of all the frogs have to offer us. (Hundt 1997)

Male frogs go through an elaborate ritual to attract mates. The male first fight among themselves to establish territories, which are then fixed for the remainder of the mating season. The male then attracts a female with vocalizations consisting of trilling sounds. Part of mating behavior involves the frogs rubbing against each other.

Mating System: polygynous

Once the courtship ritual is completed, the female lays up to six eggs in a small pool of water. The eggs are encased in a gelatinous substance for protection. The mating season of D. auratus occurs throughout the entire rainy season of the rain forest, from mid-July through mid-September.

Breeding interval: Breeding may occur more than once yearly.

Breeding season: Reproduction occurs during the rainy season, July to September.

Range number of offspring: 6 (high) .

Average time to independence: 8 weeks.

Key Reproductive Features: iteroparous ; seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; fertilization (External ); oviparous

During the two week development period, the male returns to the eggs periodically to check on them. Once the tadpoles hatch, they climb onto the males back and he carries them to a place suitable for further development, such as a lake or a stream. For the duration of this trip, the tadpoles are attached to the males back by a mucus secretion, which is soluble only in water so that there is no chance of them accidentally falling off. Once they are at their final destination, the tadpoles are on their own. They take an additional six weeks to develop into adult frogs. (Mattison 1987)

Parental Investment: altricial ; male parental care

The green-and-black poison dart frog (Dendrobates auratus), also known as the green-and-black poison arrow frog and green poison frog (among others), is a brightly colored member of the order Anura native to Central America and northwestern parts of South America. This species has also been introduced to Hawaii. It is one of the most variable of all poison dart frogs next to Dendrobates tinctorius and some Oophaga spp. It is considered to be of least concern from a conservation standpoint by the International Union for Conservation of Nature.