Sex inversion of Epinephelus microdon, a protogynous hermaphrodite was studied using light and electron microscopic criteria. The sex changes takes place within ex-ovarian lamellae in which, in addition to spermatogonia, numerous primordial germ cells (PGCs) were detected. These undifferentiated and bipotential early germ cells are involved, as well as spermatogonia, in the building up of the t...

The mangrove formations of Godavari estuary are due to silting over many centuries. The estuary covers an area of 62,000 ha of which dense Coringa mangrove forest spread in 6,600 ha. Satellite sensor data was used to detect change in the mangrove cover for a period of 12 years (1992-2004). It was found that an area of about 1,250 ha of mangroves was destroyed by anthropogenic interference like ...

During a predation event a juvenile grouper, rock hind Epinephelus adscensionis, fed upon the redlip blenny Ophioblennius trinitatis. It is important to highlight that both individuals had pretty much the same size during the predation event (around 5 cm); however, the grouper ingested the whole prey.

Tidal dynamics of shallow estuaries and lagoons is a complex matter that has attracted the attention of a large number of researchers over the last few decades. The main purpose of the present work is to study the intricate tidal dynamics of the Tagus estuary, which states as the largest estuary of the Iberian Peninsula and one of the most important wetlands in Portugal and Europe. Tagus has la...

A model describing macroalgal early life stages and adult dynamics was used to quantify the effects of non-adult forms on the productivity of adult macroalgae in a eutrophic estuary. Predictions indicate that during years with mild winters and low rainfall, spring blooms will occur at the expense of the growth and reproduction of overwintering adults and without the contribution of the spore ba...

The effect of macroalgal blooms and predation by wading on benthic macroinvertebrates was examined in the Mondego estuary, Portugal, during spring 1997. Introduced macroalgal cover and exclusion of predators were used to examine changes in density of macroinvertebrates using univariate and multivariate analyses. There was no evidence of changes in numbers of macroinvertebrates due to predation....