IntroductionSuspension-feeding behavior of the adult barnacle Semibalanus balanoides (L.), collected at Woods Hole, USA, in 1987 and, was studied in variable conditions of unidirectional and oscillating water flow. Barnacles growing on rocks were placed in a laboratory flume and exposed to precise patterns of water flow created with a specially designed electronic-circuit controlling a motor-driven propeller submersed in the flume. Laser darkfield and brightfield illumination were used to video-record the movement of suspended particles and dye in the flume and barnacle activity. When water was accelerated unidirectionally past feeding barnacles, they consistently changed feeding behavior from actively sweeping their thoracic appendages (cirri) through the water in slow-flow to passively holding cirri into the current in faster flow. The mean water velocity at which this behavioral switch occurred was 3.10 cm s -~. In slow-flow, each active sweep of the cirri created a feeding vortex that caused suspended particles to swirl into the capture zone of the following sweep. Barnacles in simulated wave-action conditions (oscillatory flow) fed passively, and orientated extended cirri to flow direction. Cirri were rapidly reoriented with the same frequency at which flow direction reversed. Slow-motion analysis of one barnacle feeding in oscillating flow (0.65 Hz) indicated that reversal of the orientation of the cirri began 0.19 s before the water itself started to reverse direction. In additional experiments, barnacles were exposed to a repetitive pattern of accelerating-decelerating flow. During each flow cycle, barnacles switched from active to passive feeding as water accelerated. Repeated exposure of an individual to the same flow-cycle caused a consistent decrease in the water-velocity threshold at which the behavioral switch occurred.

Mosquito-borne diseases represent a deadly threat for millions of people worldwide. However, the use of synthetic insecticides to control Culicidae may lead to high operational costs and adverse non-target effects. Plant-borne compounds have been proposed for rapid extracellular synthesis of mosquitocidal nanoparticles. Their impact against biological control agents of mosquito larval populations has been poorly studied. We synthesized silver nanoparticles (AgNP) using the aqueous leaf extract of Mimusops elengi as a reducing and stabilizing agent. The formation of AgNP was studied using different biophysical methods, including UV-vis spectrophotometry, TEM, XRD, EDX and FTIR. Low doses of AgNP showed larvicidal and pupicidal toxicity against the malaria vector Anopheles stephensi and the arbovirus vector Aedes albopictus. AgNP LC50 against A. stephensi ranged from 12.53 (I instar larvae) to 23.55 ppm (pupae); LC50 against A. albopictus ranged from 11.72 ppm (I) to 21.46 ppm (pupae). In the field, the application of M. elengi extract and AgNP (10 × LC50) led to 100 % larval reduction after 72 h. In adulticidal experiments, AgNP showed LC50 of 13.7 ppm for A. stephensi and 14.7 ppm for A. albopictus. The predation efficiency of Gambusia affinis against A. stephensi and A. albopictus III instar larvae was 86.2 and 81.7 %, respectively. In AgNP-contaminated environments, predation was 93.7 and 88.6 %, respectively. This research demonstrates that M. elengi-synthesized AgNP may be employed at ultra-low doses to reduce larval populations of malaria and arbovirus vectors, without detrimental effects on predation rates of mosquito natural enemies, such as larvivorous fishes.

The rapid spread of highly aggressive arboviruses, parasites, and bacteria along with the development of resistance in the pathogens and parasites, as well as in their arthropod vectors, represents a huge challenge in modern parasitology and tropical medicine. Eco-friendly vector control programs are crucial to fight, besides malaria, the spread of dengue, West Nile, chikungunya, and Zika virus, as well as other arboviruses such as St. Louis encephalitis and Japanese encephalitis. However, research efforts on the control of mosquito vectors are experiencing a serious lack of eco-friendly and highly effective pesticides, as well as the limited success of most biocontrol tools currently applied. Most importantly, a cooperative interface between the two disciplines is still lacking. To face this challenge, we have reviewed a wide number of promising results in the field of green-fabricated pesticides tested against mosquito vectors, outlining several examples of synergy with classic biological control tools. The non-target effects of green-fabricated nanopesticides, including acute toxicity, genotoxicity, and impact on behavioral traits of mosquito predators, have been critically discussed. In the final section, we have identified several key challenges at the interface between "green" nanotechnology and classic biological control, which deserve further research attention.

Several coral reefs of Nanwan Bay, Taiwan have recently undergone shifts to macroalgal or sea anemone dominance. Thus, a mass-balance trophic model was constructed to analyze the structure and functioning of the food web. The fringing reef model was comprised of 18 compartments, with the highest trophic level of 3.45 for piscivorous fish. Comparative analyses with other reef models demonstrated that Nanwan Bay was similar to reefs with high fishery catches. While coral biomass was not lower, fish biomass was lower than those of reefs with high catches. Consequently, the sums of consumption and respiratory flows and total system throughput were also decreased. The Nanwan Bay model potentially suggests an overfished status in which the mean trophic level of the catch, matter cycling, and trophic transfer efficiency are extremely reduced.

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