The reproductive and feeding biology of the lined seahorse, Hippocampus erectus, was studied in Chesapeake Bay. Seahorses are monogamous, and males incubate the eggs received from females in a closed brood pouch (= marsupium). Females do not play any parental care after mating. Total sex ratio and the operational sex ratio was strongly skewed toward females. Males and females had similar number of eggs/embryos and hydrated oocytes, respectively. The number of eggs/embryos found in the male brood pouch varied from 97 to 1,552 (fish from 80 to 126 mm TL), whereas the number of hydrated oocytes in female varied from 90 to 1,313 (fish from 60 to 123 mm TL). Both, the number of eggs/embryos and hydrated oocytes were better linearly correlated to total weight than to total length. The small snout and mouth size limits the feeding of the lined seahorse to small prey size. Amphypods were the predominant food items found in the guts, especially Ampithoe longimana, Gammarus mucronatus, and Caprella penantis. The lined seahorse is not abundant in Chesapeake Bay, but keeps a breeding population which is probably brought inside the bay by currents on drifting vegetation. Chances to find a partner may be difficult because of its low abundance, due to turbid waters, and its sedentary behavior.Key words: parental care, fecundity, fertility, amphipods, estuary. RESUMOReprodução e hábito alimentar do cavalo-marinho Hippocampus erectus (Teleostei: Syngnathidae) de Chesapeake Bay, Virgínia A biologia reprodutiva e alimentar do cavalo-marinho Hippocampus erectus foi estudada no estuário de Chesapeake Bay, Virgínia. Cavalos-marinhos são monógamos, sendo que o macho incuba os ovos recebidos da fêmea em uma bolsa incubadora fechada (= marsúpio). As fêmeas não desempenham qualquer cuidado com a prole após a fecundação. A razão sexual total e operacional foi fortemente direcionada para as fêmeas. sapeake Bay, mas mantém uma população reprodutiva. As chances para encontrar um parceiro são pequenas, devido à baixa abundância, às águas túrbidas e ao comportamento sedentário da espécie.Palavras-chave: cuidado paternal, fecundidade, fertilidade, anfípodas, estuário.

SynopsisThe northern pipefish, Syngnathus fuscus, and the dusky pipefish, S. floridae, co-exist in eelgrass beds in the lower York River . To compare the trophic ecology of both pipefishes, gut contents of 3488 northern pipefish, and 1422 dusky pipefish were examined and quantified by dry weight . Samples were taken with a dip net from May through November 1992 . Syngnathus fuscus fed mainly on amphipods (Gammarus mucronatus, Amphithoe longimana, and Caprella penantis), and to a lesser degree on copepods, and isopods (Edotea spp. and Erichsonella attenuata) . Syngnathus floridae fed mainly on grass shrimps (Palaemonetes pugio, P vulgaris, and Palaemonetes eggs), and to a lesser degree on copepods, isopods, and mysids (Mysidopsis bigelowi) . No seasonal trends were observed in the feeding habits of these pipefishes . Specimens of both species smaller than 100 mm TL fed mainly on copepods . Larger S. fuscus fed on amphipods, while larger S. floridae fed on grass shrimps . Schoener's diet overlap index revealed high consumption of the same prey type by both pipefish species only in July, but only for those specimens smaller than 110 mm TL . Food partitioning between both pipefish was associated with different snout sizes and shapes .

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Five species of anuran amphibians, all belonging to the family Hylidae, were collected at Praia das Neves, municipality of President Kennedy, southeastern Brazil. The species were represented by four genera: Scinax, Hyla, Aparasphenodon, and Trachycephalus. Four species (A. brunoi, Hyla albomarginata, Scinax altera, and S. cuspidatus) were found during the dry season (August 1999), and two (A. brunoi and Trachycephalus nigromaculatus) in the rainy season (February 2000). Aparasphenodon brunoi was the most abundant species in Praia das Neves. Some reproductive aspects and feeding habits of this hylid were investigated. Aparasphenodon brunoi was found mainly inside the bromeliad Aechmea lingulata, the largest plant analyzed. Fifteen specimens were collected during the dry season (August 1999) (11 males and 4 females). During the rainy season (February 2000), we collected 14 specimens (3 males, 10 females, and 1 juvenile). Sex-ratio was 1:1. Frogs ranged in snout-vent length from 31.2 to 69.3 mm. Females were larger than males. One female had 1,451 fully developed oocytes in her ovaries. The major groups of prey found in the stomachs were: Insecta, Myriapoda, and Arachnida. Blattodea, Orthoptera, Lepidoptera, and Hymenoptera (only ants) were the main food types in frequency, number, and weight. Aparasphenodon brunoi is a threatened species in many habitats of southeastern Brazil. Only natural vegetation protection may guarantee its survival during the immediate future.