The goal of this preliminary research was to provide an ethogram of social interactions among white sharks at Dyer Island's Nature Reserve (Gansbaai, South Africa) in the presence of bait. Eighty-three social interactions were observed, both from a boat and from a cage. Seven different interaction types were recognized: swim by; follow give way; follow; parallel swimming; give way; splash fights; and piggybacking. The preliminary data analysis did not reveal any significant relationship between the behavioural patterns and the sex of the sharks, but a strong correlation between behavioural patterns and the size of the animals was found. The observed displays were more often performed by animals of the same length than by animals of different size.

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The Mediterranean Large Elasmobranchs Monitoring (MEDLEM) database contains over 3000 records (more than 4000 individuals) of large elasmobranch species from 20 different countries around the Mediterranean and Black seas, observed from 1666 to 2017. The main species included in the archive are the devil fish (1 813 individuals), the basking shark (939 individuals), the blue shark (585 individuals) and the great white shark (337 individuals).In the last decades other species such as the shortfin mako (166 individuals), the spiny butterfly ray (138) and the thresher shark (174 individuals) were reported with an increasing frequency. This was possibly due to an increased public awareness on the conservation status of sharks, and a consequent development of new monitoring programmes. MEDLEM does not have a homogeneous reporting coverage throughout the Mediterranean and Black seas and it should be considered as a database of observed species presence. Scientific monitoring efforts in the south-eastern Mediterranean and Black seas are generally lower than in the northern sectors and the absence in our database of some species does not imply their actual absence in these regions. Some considerations are made on the frequency and spatial distribution of records, size structure of the observed individuals for selected species, general area coverage and species involved as by-catch by fishing gear.

1. Cage diving is the most important activity for the sustainable use of white sharks (Carcharodon carcharias). However, information related to their behaviour during ecotourism is scarce.2. This study provides useful information for monitoring C. carcharias during cagediving activities around Guadalupe Island, Mexico. Surface behaviour of 106 white sharks was recorded for 87 days on-board six cage-diving boats in 2012, 2013, and 2014.3. Of the observed sharks, 63% were immature specimens (n = 67) and 37% were considered mature (n = 39). Seventy-one per cent were males (n = 75) and 29% were females (n = 31). 4.Interactions were classified into one of the 11 behaviours: parading, close inspection, horizontal attack, vertical attack, bait catching, feeding, not feeding, buoy catching, encounter, escape, and staying. 5. Parading, close inspections, and horizontal attacks were performed more often by mature males, whereas immature females performed more vertical attacks, with no differences between mature and immature males. 6. A total of 1,542 ethograms were registered. Each ethogram consisted on average of 6.3 ± 5.6 behaviours with a significant transitional pattern from horizontal attacks to parading and close inspections, and from vertical and horizontal attacks to bait being caught. 7. A pattern related to feeding in a simple stimulus response reflex was observed. The shark's length seems to play an important role in the efficiency of the attacks, presumably resulting from the experience of mature individuals. Intentional feeding should be avoided to prevent negative effects related to ecotourism.8. This study constitutes a baseline for future research on white shark behaviour. It can be applied in other regions regardless of environmental conditions, quantity and size of the boats, and types of bait. Using this standard method could improve the monitoring, management, and conservation of this vulnerable species.

Based on recent biodiversity studies carried out in different parts of the Mediterranean, the following 19 species are included as new records on the floral or faunal lists of the relevant ecosystems: the green algae Penicillus capitatus (Maltese waters); the nemertean Amphiporus allucens (Iberian Peninsula, Spain); the salp Salpa maxima (Syria); the opistobranchs Felimida britoi and Berghia coerulescens (Aegean Sea, Greece); the dusky shark Carcharhinus obscurus (central-west Mediterranean and Ionian Sea, Italy); Randall's threadfin bream Nemipterus randalli, the broadbanded cardinalfish Apogon fasciatus and the goby Gobius kolombatovici (Aegean Sea, Turkey); the reticulated leatherjack Stephanolepis diaspros and the halacarid Agaue chevreuxi (Sea of Marmara, Turkey); the slimy liagora Ganonema farinosum, the yellowstripe barracuda Sphyraena chrysotaenia, the rayed pearl oyster Pinctada imbricata radiata and the Persian conch Conomurex persicus (south-eastern Kriti, Greece); the blenny Microlipophrys dalmatinus and the bastard grunt Pomadasys incisus (Ionian Sea, Italy); the brown shrimp Farfantepenaeus aztecus (north-eastern Levant, Turkey); the blue-crab Callinectes sapidus (Corfu, Ionian Sea, Greece). In addition, the findings of the following rare species improve currently available biogeographical knowledge: the oceanic pufferfish Lagocephalus lagocephalus (Malta); the yellow sea chub Kyphosus incisor (Almuñécar coast of Spain); the basking shark Cetorhinus maximus and the shortfin mako Isurus oxyrinchus (north-eastern Levant, Turkey).