Tropical and deep sea fish are the frontiers of our knowledge of fisheries, with new species reported at frequent intervals. Despite the fact that these environments contain the majority of fish species, we know very little about their ecology and physiology. A meeting was held in the Hotel Tropicale in Manaus, Brazil in September 1994, to summarize our present state of knowledge of the Physiology and Biochemistry of the Fishes of the Amazon. Then in 1995, Adalberto Val and Vera Maria Fonseca de Almeida e Val wrote “FISHES OF THE AMAZON AND THEIR ENVIRONMENT, Physiological and Biochemical Aspects,” published by Springer Verlag as volume 32 of their Zoophysiology series. In the current symposium, we have broadened the subject matter to include all aspects of tropical fish biology. Our knowledge of function in tropical fish is still rudimentary and this is reflected in the eclectic nature of this symposium. We hope, however, that the symposium will prove an interesting introduction to the many intriguing aspects of tropical fish biology. (Introduction)

Amazon fishes and their environment. Val, AL,VMFA Val, DJ Randall and DD MacKinlay

Relationships between oxygen uptake and activity levels in parrot fish from the Anderman Sea, Phuket. Taylor, EW, DJ Randall, JF Steffensen and NJ Bernier

The effects of plasma acid-base status on urea excretion in Nile tilapia. McKenzie, DJ, G Piraccini, P Bronzi and CL Bolis

Urea excretion in the erythrinidae, a tropical fresh water teleost fish. Moraes, G, VLP Polez, RHS Souza and JV Choudhuri

Ammonia and urea fluxes in Potamotrygon hysrix , a freshwater stingray of the Amazon. Barcellos, JFM, CM Wood and AL Val

Nitrogen metabolism in the tropical fresh water teleost Piaractus mesopotamicus submitted to environmental pH changes. Moraes G, PS Monzani, RHS Souza and AE Autran

Metabolic responses of tilapias with special reference to ambient oxygen. Kutty, MN

Gonad morphology of nile tilapia: Thailand and Taiwan strains. Del Mundo, RC

Aquatic surface respiration and cardiorespiratory responses of Piaractus mesopotamicus during graded and acute hypoxia. Rantin, FT and AL Kalinin

Respiratory aspects of fish of the Amazon. Val, AL

Hydrogen sulfide tolerance in Amazon fish. Affonso, E, and AV Waichman

The quality of the detritus used by Amazonian fish during the low water season. Yossa-Perdomo, MI and C Araujo-Lima

Histopathology of gills and accessory air-breathing organ of Lipostarcus pardalis exposed to crude oil. Ferreira da Costa, OT and ARL Farias

Influence of environmental factors on larval transport and coastal recruitment success in the silver mullet. Marin, BJ, A Quintero and JJ Dodson

Respiratory organs in erythrinid fishes. Fernandes, MN and SE Moron

Intraerythrocytic phosphates in Colossoma macropomum and Astronotus ocellatus of the Amazon. Marcon, JL and AL Val

Effects of nitrite on hematological aspects of Astronotus ocellatus of the Amazon. Silva, MNP, OTF da Costa, VMFA Val and AL Val

Gain and loss of heat resistance in the tropical fish, Astvanax bimaculatus of Venezuela. Chung, KS

Ion regulation in ion poor, acidic waters of the Rio Negro. Gonzalez, RJ

Gill morphology of the neon tetra. Wilson, J, W Vogl and DJ Randall

Ecological implications of metabolic profiles of heart and skeletal muscles of fishes of the Amazon. Val, VMFA and LLL de Paneppucci

Characterization of arginase from the tropical fresh water teleost fish Hoplerithrinus unitaeniatus . Moraes, G, VLP Polex, RHS Souza and AE Altran

Cardiac energy metabolism in Amazonian fish. Driedzic, WR, VMF De Almeida-Val