The present work on the feeding ecology of Scorpaena porcus according to season, sex and size, is the first study carried out in the rocky intertidal in the NE Atlantic. Previous studies were carried out with fish collected in fishing grounds from Mediterranean areas. A total of 106 fish were caught in monthly samplings from April 2008 to July 2010 in three areas of the rocky intertidal zone in the Gulf of Cadiz. The diet composition varied with season, size and sex. Shrimps were the main diet resource during all year, but other prey were also important depending on the season. As the size of fish increased, predation on smaller crustaceans decreased and consumption of larger crustaceans and fish augmented. Females and males based their diet on shrimps, while indeterminate fish fed largely on amphipods. No significant differences were found between feeding intensity and season, size and sex. Nevertheless, the PERMANOVA results showed that the number of prey is affected by the interaction between sex and size class. Our results highlight that S. porcus is a stenophagic species that shows a gradual segregation in the use of resources as it grows, which indicates there is no intraspecific competition in the rocky intertidal.

The stomach contents of 1096 specimens of Chelidonichthys lucerna were examined in order to analyse their diet composition according to fish size, sex, depth and season. Sampling was carried out from May 2005 to March 2007 during several bottom trawl surveys in the Adriatic Sea (north-east Mediterranean). Feeding activity was more intense in juveniles than in adults. The most important prey was Crustacea (mainly Decapoda: Brachyura, such as Goneplax rhomboides, Liocarcinus spp., Philocheras spp.) and Teleostei (mainly European anchovy Engraulis encrasicolus and black goby Gobius niger). There was no difference between male and female diet. Feeding habits varied with size, with fish dominating the stomach contents of larger specimens. Finally, fish increased in winter and crustaceans in summer. Chelidonichthys lucerna shows a generalist and opportunistic foraging behaviour, preying mainly epibenthic and nectobenthic organisms.

A recently developed technique in soil ecology is the use of the bait lamina method, for assessing the feeding activity of soil animals in situ. Here the bait lamina method (slightly adapted to tropical conditions) was used for the comparison of four closely situated sites (a primary rain forest, a secondary rain forest and two mixed-species tree plantations) in the Brazilian Amazon (project SHIFT ENV-52). The total feeding activity (portion of empty apertures in a set of laminae) and the vertical distribution of the feeding activity were evaluated for differences between the sites. The feeding activities in the primary and secondary forest were at the same level and significantly lower than in the two plantations. Feeding activity in subplots where surface litter has been experimentally removed was significantly lower than in the controls with the litter layer intact, at all four sites. The abundance of soil macrofauna or Enchytraeidae was not correlated with the results of the bait lamina tests, while the abundance of mesofauna (probably mainly Oribatida) was consistent with the pattern of feeding activity. The feeding activities as determined with bait laminae did not correlate with the decomposition activities determined with litterbags. Due to the easy applicability in combination with its feasibility for statistical evaluation and its consistent responses to site differences in experimental treatments we consider the bait lamina method to be a promising approach for the biological assessment of tropical soils.

Pacific oysters and king scallops placed individually in a recirculating flume were fed for 2 weeks with a constant concentration (120 cell ml–1) of a toxic strain of Alexandrium minutum. Fluorescence at the outlet of each experimental unit was measured continuously, and biodeposits were recovered twice daily to evaluate feeding time activity (FTA) and rates of organic filtration (OFR), ingestion (OIR) and organic absorption (OAR). Ion-pairing high performance liquid chromatography (IP-HPLC) was performed concurrently to quantify paralytic phycotoxins both (i) individually in shellfish at the end of the contamination period and (ii) in A. minutum cultures to estimate cellular toxin concentration. These data allowed comparison of the actual tissue toxin concentration (TOX) with the theoretical toxin accumulation rate (TAR) calculated from the linear relations between OAR, cell number, fluorescence and cell toxicity. The results show high FTA/TAR and FTA/TOX correlations (R2 = 0.78) for both oysters and scallops. The TAR/TOX relation, though not yet clearly defined, suggests the minimum quantity of absorbed toxin at which the accumulation process is induced.

We analysed Baltic Sea pelagic fish (herring and sprat) spatial and temporal distribution, size distribution at different depths and time of the day and diel feeding pattern. In 1995 the study area was investigated by acoustic survey for 3 d, 3, 4 and 11 October, to investigate spatial and temporal distribution of pelagic fish. The area was divided in four different transects forming a survey quadrate of 15 nautical miles of side. The survey quadrate was ensonified each day four times in the 24 h. In 1997 the acoustic survey was conducted in the same area and in the same week of the year to analyse the diel feeding cycle of herring and sprat and their size distribution by depth and time of the day using pelagic trawls. Fish abundance, from 1995 survey, was statistically different among days and survey quadrates. However, from our data it is not clear whether the variation stems from random dispersion or directed movements occurring at the temporal small-scale. Pelagic fish were dispersed during the night at the surface and aggregated during the day at the bottom. They aggregated at dawn and dispersed at dusk at the surface. For herring this distribution pattern coincided with peaks of stomach fullness analysed in the 1997 survey, while sprat seemed to continue feeding during the whole day time. Larger herring were deeper in the water column than smaller individuals. Diel vertical migrations (DVM) of pelagic fish likely mirrored zooplankton diel vertical movements and it was reasonably in response to optimal predation conditions in the sea and possibly intertwined with predation avoidance and bioenergetic optimisation.

Most dissected Nezara viridula (91.6%) from night catches had their stomach filled (half-full-full) with food, and females had a higher feeding activity than males. Females outweighed males at the ratio 1.3: 1, and an individual was heavier in October than in May. Ovarian development corresponded closely with decreasing fat body of females, and immature individuals had maximum fat in the abdomen. The spent individuals with empty stomach and fat thinly spread over the venter were relatively abundant in April and May, implicating the possibility of large-scale oviposition during these seasons.

This paper briefly discusses insect pest responses in mixed crop stands, their peculiarities and possible crop protection advantages. Results on the effects of a bean–oat diculture on the movements and feeding activity of the adult pea leaf weevil, Sitona lineatus L. are presented and discussed. Mixtures of these crops were found to significantly reduce the amount of notching of the bean leaflets by the weevil and weevil relative populations are compared to the sole bean crops, and to increase emigration from the more diverse plots.