Panama Research Articles

Sponge-feeding by the Caribbean starfish Oreaster reticulatus

The common Caribbean starfish Oreaster reticulatus (Linnaeus) feeds on sponges by everting its stomach onto a sponge and digesting the tissue, leaving behind the sponge skeleton. In the San Blas Islands, Republic of Panama, 54.2% of the 1549 starfish examined from February 1987 to June 1990 at eight sites were feeding, and 61.4% of these were feeding on sponges, representing 51 species. Sponges were fed on disproportionately heavily in comparison to their abundance, which was only 9.7% of available prey. In feeding choice experiments, 736 pieces of 34 species of common sponges from a variety of shallow-water habitats, and also 9 ind of a coral, were offered to starfish in individual underwater cages. Acceptance or rejection of sponge species was unambiguous for 31 of the 34 species, and there was a clear relationship between sponge acceptability and sponge habitat. Starfish ate 16 of 20 species that normally grow only on the reefs, but only 1 of 14 species that live in the seagrass meadows and rubble flats surrounding the reefs. The starfish live in the seagrass meadows and rubble flats, and avoid the reefs, and so the acceptable reef sponges are generally inaccessible until a storm fragments and transports them into starfish habitat. After Huricane Joan washed fragments of reef sponges into a seagrass meadow in October 1988, starfish consumed the edible species. When the seagrass meadow was experimentally seeded with tagged reef sponge fragments in June 1994, O. reticulatus consumed edible species and accumulated in the area seeded. Reef sponges that were living in a seagrass meadow, from which O. reticulatus had been absent for at least 4 yr (from 1978 to 1982), were eliminated when the starfish migrated into the area, and the sponges have been unable to recolonize up to June 1994. O. reticulatus feeding and habitat preferences appear to restrict distributions of many Caribbean reef sponge species to habitats without O. reticulatus and may have exerted significant selective pressure on defences of those sponges that live in O. reticulatus habitats.

The canopy gap regime in a secondary Neotropical forest in Panama

ABSTRACTWe mapped the occurrence of canopy gaps periodically between 1978 and 1990 in a 1.5 ha study plot within a 70-year-old (in 1978) Neotropical forest on Barro Colorado Island (BCI), Republic of Panama. The total area of the forest under canopy gaps in the plot averaged 4.3% (3.1% to 5.7%, 95% CI). There was high year-to-year variability in the rate of new gap formation. On the basis of repeated observations for four yearly intervals, the annual rate of new gap formation ranged from 0.45% y−1to 6.5% y−1. Most gaps were small. The mean size of individual gaps originally was 79 m2(range: 8-604 m2). However, large gaps (≥150 m2) occurred more frequently than expected for a secondary forest on BCI. Gaps closed rapidly the first year after formation but the rate of closure slowed thereafter. Despite the absence of any obvious environmental gradients, gaps were spatially clustered. Even in this relatively small plot, there seemed to be distinct gap-prone and gap-free areas.

Insects of Panama and Mesoamerica—Selected Studies

Insects of Panama and Mesoamerica—Selected Studies

High rates of photosynthesis in the tropical pioneer tree, Ficus insipida Willd.

Summary Diurnal courses of CO 2 and water-vapour exchange of canopy leaves of mature trees of Ficus insipida W illd . (Moraceae) were studied under natural conditions in the tropical dry forest of Parque Metropolitano near Panama City, Republic of Panama. Measurements were conducted from early January 1993 (dry season) until July 1993 (wet season). Rates of net CO 2 uptake were high throughout the study period, with up to 33.1 μmol m − 2 S −1 in the early dry season. During the dry season, gas exchange was characterized by strong reductions (“midday-depressions”) of net CO 2 uptake and stomatal conductance at noon. However, daily carbon gain and diurnal water-use efficiency of CO 2 uptake did not differ between seasons. East-exposed leaves that received direct sunlight during early morning hours showed higher CO 2 uptake rates and lost less water per CO 2 fixed than west-exposed leaves. As previously demonstrated for several canopy species from a tropical moist forest, the maximum rate of net CO 2 uptake was a good predictor of daily carbon gain.

Additions to the Acanthaceae of Panama

Additions to the Acanthaceae of Panama

Three New Species of Rustia (Rubiaceae, Condamineeae) from Panama and Ecuador

Three new species of Rustia are de- scribed, two from Ecuador (R. alba and R. viri- diflora) and one from Panama (R. dressleri). Illus- trations of the three species are provided.

The Panama Deception.

The Panama Deception.

The Pre‐Columbian Art of Panama at the Bowers Museum

(1994). The Pre‐Columbian Art of Panama at the Bowers Museum. The Historian: Vol. 57, No. 2, pp. 341-341.

Republic of Panama v. Air Panama Internacional Sa and Others

Governments — Change of government — Effects — Change of government effected by unlawful or questionable means — New regime not recognized by neighbouring State — Control of State assets located abroad — Assets located in State not recognizing new regime — Panama — Ownership of Panamanian assets in United StatesRecognition — Governments — Effect of recognition and non-recognition — Effects in law of recognizing State — Whether unrecognized government has standing to intervene in case — Dispute between recognized and unrecognized government over ownership of State assets abroadRelationship of international law and municipal law — Conduct of foreign relations — Conclusiveness of recognition of foreign government by Executive — Political question doctrineRelationship of international law and municipal law — Act of State and non-justiciability — United States act of State doctrine — Principle that United States courts will not question validity of act of foreign State performed within jurisdiction of foreign State — Head of foreign government appointing managerial personnel to State-owned national airline — Whether inquiry into legitimacy of appointments permitted under act of State doctrine44Relationship of international law and municipal law — Treaties — Effect in municipal law — Whether conferring rights upon individuals — United Nations Charter, 1946 — Charter of the Organization of American States, 1948 — The law of the United States

Checklist and bibliography of the amphibians and reptiles of Panama

Checklist and bibliography of the amphibians and reptiles of Panama

Dispersion and Mortality of Colonies of the Tropical Ant Paraponera clavata

Between 1984 and 1987 we located and recensused 217 Paraponera clavata colonies on a 50 ha plot of lowland rain forest located on Barro Colorado Island, Republic of Panama. In this study we describe patterns of dispersion of colonies of P. clavata with respect to habitat type, topography, and intercolony distance. We then used colony mortality data to determine if differential mortality contributes to observed patterns of dispersion. Colony density was 4.34/ha. Colonies were overdispersed, but were not significantly associated with habitat type or slope. Colony mortality was not significantly related to habitat type, slope, or tree species or size class. Colonies c 20 m from another colony had significantly higher mortality rates than colonies found at greater distances. Mean life expectancy of a colony was 2.5 yr. Intercolony aggression appears to be a major factor contributing to colony mortality in this species. Patterns of colony-tree association reported by Belk et al. (1989) cannot be fully explained by differential mortality, and thus appear to be due to selection by founding queens.

Insects of Panama and Mesoamerica: selected studies

Contributors The scenario Collembola Ephemeroptera Odonata Plecoptera Embiidina Orthoptera Dermaptera Isoptera Zoraptera Psocoptera Homoptera and heteroptera Thysanoptera Coleoptara Strepsiptera Neuroptera Hymenoptera Trichoptera Lepidoptera Mecoptera Diptera Abstracts Resumenes Author index Subject index.

Contributions to Avian Biogeography From the Archipelago and Lowlands of Bocas Del Toro, Panama

-New distributional information is summarized from avifaunal surveys conducted from 1987 to 1991 in the ornithologically unknown islands of the province of Bocas del Toro, Panama, and points on the adjacent mainland. These establish the region of the Laguna de Chiriqui to be of great biogeographic interest and complexity. New records include 3 species new to Panama, and 11 species and 3 subspecies new to Bocas del Toro. Two taxa of birds (Platyrinchus cancrominus and a form of Chlorophanes spiza) are relicts on islands and are not resident on the Panamanian mainland. Four pairs of species or subspecies (Anthracothorax prevostiilA. veraguensis, Glaucis aenea/G. hirsuta, Gymnopithys bicolor olivascensIG. b. bicolor, and Tangara inornata rava /T. i. languens) are shown for the first time to change abruptly over a narrow distance along the southern shore of the Laguna de Chiriqui. Received 6 January 1992, accepted 22 April 1992. THE PROVINCE of Bocas del Toro occupies the western quarter of the Caribbean coast of Panama. Its most distinctive physiographic feature is a large embayment (Laguna de Chiriqui/Bahia de Almirante) encompassing many islands, some quite large (Fig. 1). Along the southern shore of this embayment, lowland habitats are very restricted because of the proximity of mountains to the sea. Other factors that may have biogeographic significance are the presence of a deep channel (20 to 30 fathoms) between the Valiente Peninsula and Cayo Agua, and an extensive area of swamp at the southeastern corner of the Laguna de Chiriqui. Systematic ornithological collecting in Bocas del Toro began in 1926 (Kennard and Peters 1928) and continued actively for a few years, but then fell off for a quarter century (Eisenmann 1957). Alexander Wetmore made substantial collections for the Smithsonian Institution in 1958, but with minor exceptions almost exclusively near Almirante. In the 1960s, the Gorgas Memorial Laboratory operated hundreds of mist nets near Almirante in connection with epidemiological research, which added considerably to ornithological knowledge of the

The Speech of the Negros Congos of Panama

The Speech of the Negros Congos of Panama

Incidence and antimicrobial resistance of Salmonella serotypes in southern Taiwan from 1978 through 1987.

A total of 3,269 Salmonella strains, isolated from patients suffering from salmonellosis, was divided into 43 different serotypes during the period between 1978 and 1987. The commonest ten serotypes in the order of prevalence were S. typhimurium (43.7%), S. muenchen (13.7%), S. panama (9.0%), S. krefeld (8.1%), S. bovis-morbificans (6.3%), S. derby (4.0%), S. anatum (2.7%), S. braenderup (1.6%), S. typhi (1.2%), and S. dumfries (0.7%). Norfloxacin was found highly effective against Salmonella isolates in vitro. Moxalactam and cefotaxime were more effective than cephalothin against strains tested. Nalidixic acid and trimethoprim-sulfamethoxazole inhibited 81-100% strains of Salmonella isolates, except S. bovis-morbificans and S. typhimurium. In general, S. typhimurium showed high incidence of multiple drug resistance. Among 1,430 strains of S. typhimurium, 158 isolates showed a uniquely high level resistance to a number of antimicrobial agents, including ampicillin, amikacin, carbenicillin, cephalothin, chloramphenicol, gentamicin, kanamycin, tetracycline and trimethoprim-sulfamethoxazole. It was noted that all S. typhi isolates in this study were sensitive to all drugs tested.

Gian Singh Sahota, Poverty Theory and Policy: A study of Panama (Baltimore and London: The Johns Hopkins University Press, 1990), pp. xvii+393, £39.50.

Gian Singh Sahota, Poverty Theory and Policy: A study of Panama (Baltimore and London: The Johns Hopkins University Press, 1990), pp. xvii+393, £39.50.

Grooming behavior of spider monkeys (Ateles geoffroyi) on barro colorado Island, Panama

Quantitative grooming data are presented for free-ranging black-handed spider monkeys (Ateles geoffroyi) on Barro Colorado Island, Republic of Panama. A total of 126 grooming sessions was recorded, with an average session length of 2.0 min (range, 0.1 to 10.0 min). Grooming was an infrequent behavior; on average, individuals allocated only 2.5% of their daily activity to grooming. Two daily peaks of grooming activity were observed, one near midday and another in the late aftermoon between 1600 and 1700. Adult females groomed most frequently, followed by males and then juveniles. Juveniles were the most frequent recipients of grooming, followed by females and then males. Individual preferences were observed primarily between mother-offspring, male-male, and juvenile-male grooming partners in this male-bonded fission-fusion, species. Grooming interactions reflect many of the social characteristics of spider monkey societies: intraclass grouping preferences, long period of juvenile dependence, male philopatry, and female dispersal.

Review of Lipski (1989): The speech of the negros congos of Panama

Review of Lipski (1989): The speech of the negros congos of Panama

The Speech of the Negros Congos of Panama

The Speech of the Negros Congos of Panama

The effect of the density of flowering individuals on the mating systems of nine tropical tree species

Mating systems were examined through allozyme analysis for nine tropical tree species that occur on Barro Colorado Island, Republic of Panama. Estimates of outcrossing rates, using a mixed mating model, ranged from 0.35 to 1.08. Most species were highly outcrossed but two species that occurred at low densities had outcrossing rates below 0.7. Heterogeneity among trees in pollen allele frequencies contributing to progeny arrays was significant. The degree of heterogeneity in pollen allele frequencies was measured by Wright's FST, treating progeny arrays as populations. Mean FST values were negatively correlated with flowering tree density, which indicates that trees at low density sample pollen from fewer individuals than trees in denser populations. Among-year heterogeneity in pollen allele frequencies for two species was also related to the density of flowering individuals; years with lower flowering tree density had greater heterogeneity and/or more selfing. These results indicate that several population parameters, such as inbreeding, genetic relatedness of progeny arrays, gene flow and effective population size are associated with the density of flowering individuals and thus vary from year to year and among locations.