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The acoustic behaviour of the European spiny lobster Palinurus elephas (Fabricius, 1787) was examined in the absence or presence of predators or conspecifics. Observations were conducted in a tank equipped with digital video and acoustic monitoring and recording systems using 25 adult lobsters and 5 common octopuses Octopus vulgaris. Single lobsters or groups of 4 lobsters were studied for 2 h. These were left alone during the first hour and exposed to a single specimen of the common octopus during the second hour. The lobsters' signals were acoustically analysed. Signal duration, number of pulses per signal, pulse rate, bandwidth, peak intensity, and peak frequency were measured. Single lobsters emitted a higher number of signals than lobsters belonging to a group. The signal (rasp) was audible to humans only in the presence of a predator and was always associated with specific behavioural events. In the absence of a predator, the lobsters produced ultrasound signals (screech) having lower duration, number of pulses per signal, bandwidth, and peak intensity and higher pulse rate and peak frequency. Audible rasps were produced in an anti-predator context, whereas the ultrasound screeches were also emitted under non-stressful conditions. Thus, these signals may play a role in intraspecific communication. KEY WORDS: Acoustic behaviour · Palinurus elephas · Intraspecific communication · Antipredator behaviourResale or republication not permitted without written consent of the publisher OPEN PEN ACCESS CCESS

There is some evidence that the presence of Tursiops truncatus in fishing areas represents a real economic threat to fishermen due the dolphin feeding on the entangled fish, damaging the nets and reducing the fish catch. We have carried out experiments to assess the efficiency of a pinger in decreasing the interaction between the dolphins and fishing nets, in a fishing area off the coast of southern Italy, where Tursiops truncatus is frequently observed to interact with bottom gill nets. Two identical monofilament bottom gill nets (900 m long), one equipped with pingers and the other without, were used to measure the effect of these pingers on the abundance of the catch and net damage. For each haul (58 in total), data on dolphin sightings near the nets, damage judged to have been done by dolphins, weight and species composition of the catch were collected. All damage to the nets were recorded at the end of each haul. Dolphins in the fishing area were sighted 11 times out of 29 fishing activities (38%). The net equipped with pingers contained 28% more fish (biomass) than the net without pingers (t test, P \ 0.04) and was less damaged (-31%, t test, P \ 0.01). To assess whether the efficacy of these pingers remain constant over long period, long-term experiments should be carried out.

The aim of the present work was to reveal the behaviour of the European spiny lobster Palinurus elephas (Fabricius, 1787) during encounters with predators. The study was conducted in a tank, exposing lobsters individually or in groups to a single specimen of the European conger eel or the common octopus. The behaviours of the lobsters, their sounds and the behaviours of the predators were recorded using a digital audio-video underwater acquisition system and analysed. A behavioural event not found in literature, dubbed 'Alert' by the authors, was described. The results showed that the most recurrent events were Alert, Point and Whip, which have the function of controlling the predator with the antennae, while maintaining the predator-prey distance. Moreover, a strong association between Tail Flip and Lunge (events that were stimulated in response to an imminent danger to life) with the sounds emitted by lobsters was observed. Significantly more sounds were emitted during the tests with single lobsters compared to grouped lobsters. As a result of the present study, the European conger eel may also be considered a potential natural predator of the European spiny lobster.

Concentrations of trace elements (Cd, Pb, As, V, Cr, Ni, Cu and Zn) were determined in superficial sediments and in muscle and hepatopancreas tissues of the red swamp crayfish Procambarus clarkii from Lake Preola and Gorghi Tondi Natural Reserve (SW Sicily). In particular, hepatopancreas showed a decidedly higher content of all analysed trace elements with respect to muscles (two- to threefold higher for Cd, Cu, As, Zn and V; four- to fivefold higher for Pb and Cr and seven times higher for Ni). However, no statistically reliable differential accumulation pattern emerged with regard to length and weight for trace elements (except for Cd for which significant positive correlations with length were recorded). Trace element concentrations found in crayfish tissues were in the range considered harmful to human health (except for Cd and Cr). Moreover, the As and Pb concentrations, either in sediment or crayfish tissues, are clearly related to intense agricultural activities, with extensive use of fertilizers and pesticides, that significantly affect the levels of these toxic metals in the study area.

Trace metal concentrations were measured in different tissues of Sabella spallanzanii, Styela plicata, and Mytilus galloprovincialis collected in the Termini Imerese Harbor (Sicily, Italy) to evaluate the potential use of these species as bioindicators. Higher bioaccumulation factors (BAFs) were calculated in the tube of S. spallanzanii, except for As, which had a higher BAF in the branchial crown of the same species. Regarding the other species analyzed, higher BAFs were found in the digestive gland of M. galloprovincialis. An exception was Pb, which was significantly more concentrated in the branchial basket and tunic of S. plicata. The BAFs calculated in the present study show that all the species analyzed accumulate a certain amount of metals as a consequence of filter feeding mechanisms, and thus it was possible to assess the suitability of S. plicata, S. spallanzanii, and M. galloprovincialis as indicators of water quality. In particular, the tube of S. spallanzanii is an important compartment in terms of metal retention and is more suitable for the evaluation of contamination from trace elements. Environ Toxicol Chem 2016;35:3062-3070. © 2016 SETAC.

of carbon and nitrogen stable isotopes to study the feeding ecology of small coastal cetacean populations in southern Brazil. Biota Neotrop. 13(4): http://www.biotaneotropica.org.br/v13n4/en/abstract?article+bn01413042013Abstract: Samples from individuals of the populations of Sotalia guianensis (Guiana) and Pontoporia blainvillei (Franciscana) dolphins living in the Babitonga Bay estuary (26° 28' S/48° 50' W), and samples from individuals of a second population of P. blainvillei from a nearshore area (26° 38' S/48° 41' W), were collected and analyzed along with their prey between 2000 and 2006, to determine the carbon and nitrogen stable isotope ratios and to verify differences in their feeding ecology. No differences were found in the median ð 15 N values of Guiana (15.2‰) and Franciscana (15.9‰) dolphins living in Babitonga Bay, nor of nearshore Franciscana (15.0‰) individuals, suggesting no variation in the trophic level of these populations. However, the lack of more information on the isotopic compositions of their putative prey in the nearshore areas prevents the ability to draw definitive conclusions on this issue. The estuarine Franciscana and Guiana dolphin populations presented mean ð 13 C values of approximately -15.7‰, which were not statistically different from nearshore Franciscana individuals (-14.8‰). Based on stomach content analyses of these species from a previous study, it was reported that there was little overlap in the diet of estuarine Franciscanas and Guiana dolphins. However, based on the similarity of the ð 13 C values between these two species and of their putative prey, it appears that in fact there is an overlap in the diet of these two species. Based solely on stable isotope analysis, it was not possible to differentiate between estuarine and nearshore Franciscana populations, making it difficult to conclude whether captured nearshore specimens were indeed yearlong residents of these areas. Finally, this study suggests that Franciscana and Guiana dolphin populations are sharing the same resources, mostly L. brevis, D. rhombeus, and S. rastrifer. Therefore, the combination of resource sharing and commercial exploitation of their prey makes these two cetacean species vulnerable. Keywords: Pontoporia blainvillei, Sotalia guianensis, Babitonga Bay, feeding ecology, trophic level.HARDT, F.A.S., CREMER, M.J., TONELLO JUNIOR, A.J., BELLANTE, A., BUFFA, G., BUSCAINO, G., MAZZOLA, S., BARRETO, A.S., MARTINELLI, L.A. & ZUPPI, G.M. O uso dos isótopos estáveis de carbono e nitrogênio para o estudo da ecologia de populações de pequenos cetáceos costeiros no sul do Brasil. Biota Neotrop. 13(4): http://www.biotaneotropica.org.br/v13n4/pt/abstract?article+bn01413042013Resumo: Amostras de tecido de indivíduos pertencentes às populações de Sotalia guianensis (boto-cinza) e Pontoporia blainvillei (toninha) que vivem no estuário da Baía da Babitonga (26° 28' S/48° 50' W) e de uma segunda população de P. blainvillei da área costeira (26° 38' S/48° 41' W) foram coletadas entre os anos 2000 e 2006 para ...