5 research outputs found
Feeding Habits of Dwarf Goatfish (Upeneus parvus: Mullidae) on the Continental Shelf in the Gulf of Mexico
Feeding habits of dwarf goatfish on the continental shelf off Alvarado, Veracruz, Mexico, were analyzed to determine seasonal variation and size-class changes in diet composition and trophic overlap between size classes. Food was found in 63% of the 1,437 dwarf goatfish guts analyzed. The 52 dietary items identified consisted mainly of crustaceans, with Solenocera vioscai being the most important prey. Dwarf goatfish exhibited seasonal and size-class changes in prey consumption. Despite the high number of prey items, low values of diversity and diet breadth were found in the trophic spectrum. A high trophic overlap between size classes was observed in the north-winds season between length classes (92-111 vs 112-130 mm) (λ = 0.81) and (92-111 vs 131-150 mm) (λ = 0.80), and (112-131 vs 131-150 mm) (λ = 0.67). In the rainy season high overlaps were obtained between (92-111 vs 112-131 min) (λ = 0.73) and (112-131 vs 131-150 mm) (λ = 0.84) length classes. Dwarf goatfish appear to be opportunistic carnivorous predators that impact benthic and epibenthic invertebrates
Trophic biology contributions of the slender-spined catfish Arius platypogon (Günther, 1864), in San Ignacio Lagoon, Baja California Sur, México
Feeding Habits and Trophic Morphology of Inshore Lizardfish (Synodus foetens) On the Central Continental Shelf off Veracruz, Gulf of Mexico
The inshore lizardfish, Synodus foetens, is one of the most common coastal demersal predators on the continental shelf of the Gulf of Mexico (GOM), but the biology and feeding ecology of this species is virtually unknown. Between November 2001 and January 2003 (10 collections), 603 individuals of S. foetens ranging from 112 to 420 mm standard length (SL) and 13 to 630 g (wet weight) were collected from the continental shelf of Alvarado, Veracruz, Mexico. About 60% of the individuals had empty stomachs with the stomach fullness of the remaining individuals being distributed as follows: 5% full (24.8%), 50-75% full (13.5%), and completely full (1.7%). The mean (+/- SD) wet weight of stomach contents was 12.1 +/- 10.8 g during the rainy season, and 19.0 +/- 13.0 g during the nortes season. Seventeen prey items were identified, with the majority thereof being fish. The most important prey items were Upeneus parrus, Loligo pealei, Engyophrys senta, Trachurus lathami, and Anchoa hepsetus. Seasonal changes in the diet were observed, with U. parrus and L. pealei being the most important prey during the nortes season, whereas E. senta and L. pealei were the main items during the rainy season. Prey size selection was evident among size classes of S. foetens, although no trophic overlap was observed among size classes (C-lk \u3c= 0.004). High trophic level values were determined for all size classes by season (rainy season = 4.67, nortes season = 4.84), and indicated this species belongs to the piscivorous trophic guild that preys upon both demersal and pelagic species
Brotações adventícias de abacaxizeiro ornamental sob o efeito de benzilaminopurina, ácido naftalenoacético e períodos de subcultivo Adventitious shoot of ornamental pineapple under benzylaminopurine, naphthalene acetic acid and subculture period effect
O objetivo deste trabalho foi avaliar os efeitos da adição de benzilaminopurina (BAP), em combinação com o ácido naftalenoacético (ANA), e dos períodos de subcultivo, na formação de brotações in vitro de abacaxizeiro ornamental. O meio básico líquido consistiu de sais minerais MS e vitaminas. O delineamento experimental utilizado foi o inteiramente casualizado, em esquema fatorial 6x2x4, com seis concentrações de BAP (0, 0,125, 0,25, 0,5, 1 e 2 mg L-1) e duas de ANA (0 e 0,1 mg L-1), e quatro períodos de subcultivo (30, 60, 90 e 120 dias). Os explantes consistiram de brotações individuais de 1 cm de comprimento, oriundas da cultura in vitro. A formação de novas brotações foi observada em meio suplementado com BAP, em todos os períodos de subcultivo. O maior número médio de brotos por explante foi obtido em meio com a concentração de 1,2 mg L-1 de BAP e 120 dias de subcultivo.<br>The objective of this work was to evaluate the effect of benzylaminopurine (BAP) additions, in combination with naphthaleneacetic acid (NAA), and of subcultures periods on in vitro shoot formation of ornamental pineapple. The basal liquid medium consisted of MS salts and vitamins. The experiment was a completely randomized design, in a factorial arrangement 6x2x4, with six concentrations of BAP (0, 0.125, 0.25, 0.5, 1, e 2 mg L-1) and two of NAA (0 and 0.1 mg L-1), and four subculturing periods (30, 60, 90 e 120 days). The explants consisted of individualized shoots with 1 cm length from in vitro cultures. Shoot formation was observed in medium supplemented with BAP in all subculturing periods. The greatest average number of shoots per explant was obtained with BAP concentration of 1.2 mg L-1 and 120 days of subcultive