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Photos by Philippe J. R. Kok

REPTILIA 47 According to DALY et al. (1994b), the of the are unable to take up lipophilic alkaloids. Nonetheless, one species, (Cope, 1868), from Colombia, is known to be toxic (DALY et al., 1994a). Rocket are found from cen- tral Costa Rica to northern Peru and the Guianas (Guyana, Suriname, and French Guiana), and through the Amazon Basin to southeastern Brazil, as well as on the Caribbean island of Martinique (FROST, 2004). Colostethus species can be found at different elevations ranging from sea level to about 4,000 meters. Most rocket frogs are primarily diurnal, ground-dwelling inhabitants of the leaf litter in tropical forests. The genus Colostethus shows great interspecific variability in repro- ductive behavior. Tadpoles of some species are exotrophic (feeding on materials not derived from a parent); tadpoles of other species are endotrophic (deriving their develop- mental energy and nutrition from vitellogenic yolk or other parent- At least three golden rocket frogs inhabit this giant terrestrial bromeliad produced material) (ALTIG and JOHNSTON, 1989). to find. COLOMA (1995) presented (FRANK and RAMUS, 1995). The Guyana. NOBLE (1923) distin- Similarity in coloration, pattern, disturbing evidence of declines in male reaches 16.6 millimeters in guished the new species from other and morphology between different Ecuadorian populations of some length; the female 19 millimeters Colostethus species by its small size, species of Colostethus, combined Colostethus species. Habitat destruc- (BOURNE et al., 2001). The species brilliant coloration (extremely unusu- with conspecific color-pattern poly- tion and global warming are probably was first described from a single al for the genus), and short but well- morphism (variation within single the main causes of decline, but a com- female specimen collected in 1921 by defined webbing between the toes. species), has led to some taxonomic plex of factors including, diseases, William Beebe near Kaieteur Falls, BOURNE (2001) recognized five confusion, especially within the increased UV radiation, environmen- different color-pattern morphs, three species of the Guianas. For example, tal acidification, and agrochemicals of which are brilliantly colored. In Colostethus beebei (Noble, 1923), are also implicated (POUGH et al., June 2004, during the first phase of which does not occur in French 2004). The paucity of data on the sta- our sampling of the Kaieteur herpeto- Guiana, has been erroneously tus of populations is clearly a major logical richness, we collected two reported from there on several occa- limitation on our ability to monitor clearly distinct morphs: one bright A small micrantha, exclusive biotope of the golden rocket , with Kaieteur Falls in the background sions (LESCURE, 1976; LESCURE declines. Reliable data showing yellow (the most commonly seen), and MARTY, 2000; HOOGMOED trends in population numbers is need- and one brown. We observed the The genus Colostethus In fact, no fewer that 25 species and AVILA-PIRES, 1991; BOISTEL ed for accurately determining threat types of discrete variation within the Cope, 1866, a Neotropical have been described just since the and DE MASSARY, 1999; KOK, status. Colostethus populations seem yellow morph and brown morph as dendrobatid frog, encom- beginning of the 21st century, most- 2000; FROST, 2004). Colostethus to remain stable in protected areas, detailed by BOURNE (2001). passes more than 120 ly from Colombia, Brazil, and Peru. brunneus (Cope, 1887) has been but this must be confirmed by extant species (FROST, Colostethus species diversity appears reported from the Guianas, but field censuses. In any case, endemic Distribution and habitat 2004), commonly known as the rock- to be greatest in northwestern South the frogs seen probably belong to species with very restricted geograph- As far as we know, Colostethus et frogs (FRANK and RAMUS, America, decreasing to the east, one or more undescribed species ical ranges should always be consid- beebei is endemic to Guyana, and 1995) because of their explosive southeast, and north (into Central (MORALES, 2002). ered at risk (POUGH et al., 2004). occurs only in Kaieteur National jumping ability. Many new species America). Many Colostethus species have Park. Guyana is known as “Land of of Colostethus have been described Rocket frogs are usually small with suffered severe local population Description Many Waters” because of its numer- in the past few decades, and we cryptic coloration, lacking the toxins declines during the past 10 to 20 Colostethus beebei is a tiny, charis- ous rivers and streams. The country The most commonly seen bright-yellow morph assume that many others still await and aposematic coloration character- years, and some species that were matic frog commonly called the gold- was usually seen on live green leaves, but lies over part of the Guiana Shield discovery and scientific description. istic of most other dendrobatids. once very abundant are now difficult en rocket frog, or Beebe’s rocket frog sometimes also on dead brown leaves (or Guiana Highlands), one of the

REPTILIA 48 REPTILIA 49 world’s oldest geological formations, renowned for its rich . The higher, central parts of the Guiana Shield are covered with sandstone remnants of the Roraima formation (HOOGMOED, 1979), a breathtaking landscape marked by more or less flat-topped peaks called “tepuis.” Sir Arthur Conan Doyle’s The Lost World was inspired by this area. The Pakaraima Mountains of central-western Guyana are part of the Roraima sandstone formation. Kaieteur Park, one of the first national parks established in South America (in 1929 by the British Commonwealth) has recently been expanded to encompass an area of 62,680 hectares (154,882 acres) Mist rising from the falls forms a cloud-forest habitat occupied by specialized species along the rim of the gorge (KELLOFF, 2003). The centerpiece of the park is the impressive Kaieteur Falls situated where the Pakaraima Mountains give way to the coastal lowlands. With a volume of 600,000 liters per second going over an unin- terrupted single drop of 226 meters, Kaieteur is one of the most powerful waterfalls on Earth. This pounding Portrait of a bright orange-yellow morph of Colostethus beebei behemoth has carved a huge gorge, and expels millions of liters of water dead brown leaves, whereas the breeding in the water-filled leaf axils, amicable visits (social interactions as mist. In conjunction with prevail- bright yellow morph is more com- or tanks, of the bromeliads they without aggression) between neigh- ing winds, this mist appears to influ- monly seen on live green leaves. We inhabit — they do not gather at other bors. This is the first report of non- ence the densities of Colostethus made similar observations, occasion- aquatic sites for mating, as many oth- reproductive sociality for unrelated beebei (BOURNE et al., 2001). A ally finding a few of the bright yellow er anurans do. Social behavior in individuals in any frog species. cloud-forest environment formed by frogs on dead brown leaves, but very generally involves inter- BOURNE (unpublished data) rising mist along the crest of the rarely finding brown frogs on live actions only in conjunction with mat- induced group-living and changes of gorge also harbors endemic flora green leaves. ing, but our observations and earlier residence in captive Colostethus bee- Aerial view of Brocchinia micrantha glades on the Kaieteur Tepui, where golden rocket frogs still abound (KELLOFF, 2003). The Kaieteur plateau supports experiments by BOURNE (unpub- bei by manipulating the temporal and Colostethus beebei is the only unique and interesting habitat types. lished data) indicate that golden rock- spatial distribution of water — find- species of its genus known to be a Brocchinia spp. dominated savannas, et frogs also interact with their con- ings supported the hypothesis that bromeliad specialist — it lives and for example, harbor another endem- specific neighbors on an everyday sociality allows individuals to monitor breeds exclusively on the giant ic frog, Tepuihyla talbergae, recent- basis. On the premise that group-liv- spatial and temporal distribution of terrestrial bromeliad Brocchinia ly described by DUELLMAN and ing naturally accrues costs but not water, thereby minimizing mortality micrantha (BOURNE et al., 2001). YOSHPA (1996). During the day- necessarily benefits to individuals, we by desiccation. We speculate that the These giant bromeliads grow in time Tepuihyla talbergae often takes investigated why golden rocket frogs daily visits between neighbors humus caught in rock crevices, and refuge in the much smaller, insectivo- should remain together beyond the increases recognition of individuals can reach 3.5 meters in height rous terrestrial bromeliad Brocchinia time required for reproduction. and thereby reduces energy expend- (KELLOFF, 2003). Golden rocket reducta, but can sometimes also be The number of golden rocket frogs ed competing for access to pools. frogs are found in open glades where found in the giant bromeliads with living on a single bromeliad was pre- Colostethus beebei courtship (as in the giant bromeliads are abundant. Colostethus beebei. dicted to depend on the volume of other dendrobatids) is long and elab- The frog population densities are water, amount of dissolved oxygen, orate, including close-range vocal, highest in close proximity to Kaieteur Ecology and behavior and (negatively) accumulation of leaf visual, and tactile stimulation. The Falls, but the species has also been BOURNE (2001) and BOURNE litter in the bromeliad tanks. Water female lays a clutch of three to seven observed as far as about 1 kilometer et al. (2001) studied the ecology and was found to be an important resource eggs on leaves just above the water- away on the Potaro plateau. behavior of the golden rocket frog on for non-breeding golden rocket frogs. filled axil of the bromeliad. There is a BOURNE (2001) reported that the Kaieteur plateau. They found Although males and females estab- correlation between the number of the brown morph of the golden rock- that male and female golden rocket lished individual all-purpose territo- clutches laid and the distance from et frog is more commonly seen on Typical habitat of Colostethus beebei on the Potaro River plateau frogs live together in stable groups, ries, they exhibited a pattern of daily the waterfall. More clutches were

REPTILIA 50 REPTILIA 51 tat alteration within the small range enthusiastic field assistance. C. M. YASUMOTO. 1994a. First occurrence of Herpetofauna of Petit Saut, Sinnamary River, of Colostethus beebei. Fortunately, Bourne and anonymous colleagues tetrodotoxin in a dendrobatid frog French Guiana. Zoologische Mededelingen the populations of this species in Kai- provided constructive comments that (Colostethus inguinalis), with further reports 65: 53–88. for the bufonid genus Atelopus. Toxicon KELLOFF, C. L. 2003. The Use of Biodi- eteur National Park appear to be improved this article. 32(2): 279–285. versity Data in Developing Kaieteur National healthy and quite stable at present. DALY, J. W., S. I. SECUNDA, H. M. Park, Guyana for Ecotourism and Conserva- Golden rocket frogs are fascinating Bibliography GARRAFFO, T. F. SPANDE, A. WIS- tion. Contributions to the Study of Biological creatures, which might attract hobby- ALTIG, R., and G. F. JOHNSTON. 1989. NIESKY, and J. F. COVER, Jr. 1994b. An Diversity 1: 1–44. uptake system for dietary alkaloids in poison KOK, P. J. R. 2000. A Survey of the Anu- ists to keep them in captivity. This Guilds of Anuran Larvae: Relationships among developmental modes, morphologies, frogs (Dendrobatidae). Toxicon 32(6): ran Fauna of Montagne Belvédère, County of article is certainly not meant to pro- and habitats. Herpetological Monographs 3: 657–663. Saül, French Guiana: Field List with Com- mote the exploitation of Colostethus 81–109. DUELLMAN, W. E., and M. YOSHPA. ments on and Ecology. The British beebei for the pet trade. Kaieteur BOISTEL, R., and J-C. DE MASSARY. 1996. A new species of Tepuihyla (Anura: Herpetological Society Bulletin 71: 6–26. National Park is a protected area, 1999. Les amphibiens vénéneux de la famille ) from Guyana. Herpetologica 52: LESCURE, J. 1976. Contribution à l’étude des dendrobatidés. Le Courrier de la Nature 275–281. des amphibiens de Guyane française. VI. within which it is illegal to collect or 176: 38. FRANK, N., and E. RAMUS. 1995. A Liste préliminaire des anoures. Bulletin du even disturb wildlife of any species, BOURNE, G. R. 2001. Color Pattern, Complete Guide to Scientific and Common Museum national d’Histoire. Naturelle de or . Our aim is primarily Predator Avoidance, and Foraging Behavior Names of Reptiles and Amphibians of the Paris (3) 265: 475–525. to promote Colostethus beebei as a in the Golden Frog Colostethus beebei (Anu- World. N. G. Publishing, Pottsville, Pennsylva- LESCURE, J., and C. MARTY. 2000. ra: Dendrobatidae). Herpetological Review nia. Atlas des Amphibiens de Guyane. charismatic representative of the bio- 32(4): 225–228. FROST, D. R. 2004. Species of SPN/MNHN, Paris, Patrimoines naturels 45: ta of Kaieteur — an ambassador for BOURNE, G. R., A. C. COLLINS, A. M. the World: an Online Reference. Version 3.0 1–388. increased awareness, education, and HOLDER, and C. L. McCARTHY. 2001. (22 August, 2004). http://research.amnh.org/ MORALES, V. R. 2002. Sistemática y Bio- conservation. We feel it is important Vocal Communication and Reproductive herpetology/amphibia/index.html. American geografía del grupo trilineatus (Amphibia, Tepuihyla talbergae, another frog species endemic to Kaieteur National Park, is sometimes found with to share information on this poorly Behavior of the Frog Colostethus beebei in Museum of Natural History, New York. Anura, Dendrobatidae, Colostethus), con Colostethus beebei in the same bromeliads Guyana. Journal of Herpetology 35(2): HOOGMOED, M. S. 1979. The her- descripción de once especies nuevas. Publica- known species, and to emphasize the 272–281. petofauna of the Guianan region. In: W. ciones de la Asociación de Amigos de Doñana found in bromeliads near the water- also prey on the juvenile and adult importance of Kaieteur National COLOMA, L. A. 1995. Ecuadorian Frogs E. Duellman (ed.). The South American 13: 1–59. fall than in bromeliads away from the frogs. Park as a protected area. The conser- of the Genus Colostethus (Anura: Dendro- herpetofauna: Its origin, evolution, and NOBLE, G. K. 1923. New batrachians influence of the mist, suggesting that The golden rocket frog is primarily vation value of any region increases batidae). Miscellaneous Publication of the dispersal. Monograph of the Museum of from the Tropical Research Station British University of Kansas Natural History Museum Natural History, University of Kansas 7: Guiana. Zoologica 3(14/15): 288–305. the species depends on the high a sit-and-wait predator. It feeds with the extent of endemic species 87: 1–72. 241–279. POUGH, F. H., C. M. JANIS, and J. B. humidity provided by the mist. mainly on emerging mosquito and there, and we are convinced that DALY, J. W., F. GUSOVSKY, C. W. HOOGMOED, M. S., and T. C. S. AVILA- HEISER. 2004. Vertebrate Life. Pearson Both parents provide care of off- midge imagoes, but also on ants, intelligent management of parks and MYERS, M. YOTSU-YAMASHITA, and T. PIRES. 1991. Annotated Checklist of the Prentice Hall, Upper Saddle River, NJ. spring. During times of low humidity, mites, small spiders, and on the same protected areas is the best way to the male squirts fluid from his cloaca unidentified drosophilid fly whose ensure the survival of endemic onto eggs to moisten them. larval stage depredates the eggs of the species and their landscapes. On hatching, the tadpoles slide into frog (BOURNE, 2001). The golden the bromeliad tank (phytotelmatum) rocket frog apparently owes its bril- Acknowledgments where they feed on algae, detritus, liant coloration to diet-derived We gratefully acknowledge the and mosquito and midge larvae. carotenes. BOURNE (2001) noted financial support of the Directorate Occasionally, if there is no food in the that in his captive research specimens General of Development Coopera- pool, the male may transport tadpoles the brilliant yellow faded in a few tion (Belgian Development Coopera- on his back (one or two at a time) to months. When fed on paprika-forti- tion), the Smithsonian Institution’s another pool. The tadpoles may also fied fruit flies, the frogs regained their Biodiversity of Guianas Program, and be supplied with unfertilized eggs to bright coloration. CEIBA Biological Center. Permis- eat — the paternal male displays sion to conduct this study was grant- renewed courtship behavior but does Conservation ed by the Prime Minister of not fertilize the eggs laid by the An endemic species with a small Guyana, the Honorable Samuel female, this time directly into the geographic range and a high degree Hinds, and S. Nockta and I. Nathoo water instead of onto the leaf. Larval of habitat specialization, it is espe- of the Guyana National Parks Com- cannibalism occurs but seems to be cially vulnerable to extinction should mission. Research and collection per- rare. Duration of larval development its particular habitat be disturbed. mits were issued by the Guyana Envi- is still unknown, but metamorphosed Anthropogenic effects such as habitat ronmental Protection Agency. Mar- juvenile frogs attain sexual maturity alteration, fragmentation, and loss garet and Malcolm Chan-A-Sue han- within 4–6 months. The species are probably the most important dled the logistics and coordinated our appears to have a life span of about 5 threats facing endemic species. The travels to Kaieteur National Park, years. endemic golden rocket frog has a very and the Nyron Rahaman family An unidentified graspid crab, the restricted distribution and is also opened up their home to us, thereby colubrid tree snake Imantodes cen- highly specialized, living and breeding making our work much easier and choa (Linnaeus, 1758), and the larva exclusively in giant bromeliads. It is more enjoyable. We thank Paul Ben- of an unidentified drosophilid fly are therefore very important that the jamin, Simone Clarke, Festus, known to feed on the eggs of the gold- government of Guyana continue Reuben, Joy, Margaret, Ann, Jane, en rocket frog; the crab and snake enforcing laws that penalize any habi- Frederick, Sammy, and Sabatini for

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