Dear colleagues,
We are pleased to announce our last three articles published by our research team. *1:* Giménez, J., Louis, M., Barón, E., Ramírez, F., Verborgh, P., Gauffier, P., Esteban, R., Eljarrat, E., Barceló, D., Forero, M.G., and de Stephanis, R. (2017) Towards the identification of ecological management units: A multidisciplinary approach for the effective management of bottlenose dolphins in the southern Iberian Peninsula. Aquatic Conservation: Marine and Freshwater Ecosystems. *2:* Giménez, J., Marçalo, A., García‐Polo, M., García‐Barón, I., Castillo, J. J., Fernández‐Maldonado, C., Saavedra, C., Santos, M.B., and de Stephanis, R. (2017). Feeding ecology of Mediterranean common dolphins: The importance of mesopelagic fish in the diet of an endangered subpopulation. Marine Mammal Science. *3:* Giménez, J., Marçalo, A., Ramírez, F., Verborgh, P., Gauffier, P., Esteban, R., Nicolau, L., González-Ortegón, E., Baldó, F., Vilas, C., Vingada, J., Forero, M.G., and de Stephanis, R. (2017). Diet of bottlenose dolphins (*Tursiops truncatus*) from the Gulf of Cadiz: Insights from stomach content and stable isotope analyses. PloS one, 12(9), e0184673. You can find the abstracts below. ABSTRACTS 1: Determining discrete and demographically independent management units within wildlife populations is critical for their effective management and conservation. However, there is a lack of consensus on the most appropriate criteria to delimit such management units. A multi‐ disciplinary, multi‐scale approach that combines tools informing in the short‐term (i.e. photo-identification), with mid‐term ecological tracers (stable isotopes–δ13C, δ15N and δ34S– and persistent organic pollutants –POPs–), and mid‐ to long‐term genetic markers (microsatellites and mitochondrial DNA), was used to define management units within bottlenose dolphins (*Tursiops truncatus*) inhabiting the southern Iberian Peninsula. Although genetically indistinguishable, individuals inhabiting the Strait of Gibraltar and the Gulf of Cadiz showed differences in their isotopic composition and the concentrations of certain POPs. Accordingly, the lack of photographic recaptures between the two sites pointed to the existence of at least two different ecological management units that segregate spatially and may require different conservation strategies. Different time‐scale approaches can reveal different management units. The results highlighted the use of medium‐ and short‐term approaches for properly identifying ecologically different units for effective management and conservation. Furthermore, these results have important management implications as European legislation promotes specific management plans for this species. 2: The Mediterranean subpopulation of common dolphin (*Delphinus delphis*) is classified as endangered by the IUCN. Still, information about their diet in the Mediterranean is scarce. Stomach contents of 37 common dolphins stranded in the Alboran Sea and Strait of Gibraltar were analyzed. A total of 13,634 individual prey of 28 different taxa were identified. For fish, Myctophidae was the most important family as indicated by the highest index of relative importance (IRI =8,470), followed by the family Sparidae (IRI =609). The most important Myctophidae species was Madeira lantern fish (*Ceratoscopelus maderensis*) and for Sparids, the bogue (*Boops boops*). Cephalopods, instead, were found in low quantities only with 31 prey from the Loliginidae, Ommastrephidae, and Sepiolidae families. Overall, our results indicate that common dolphins are mainly piscivorous (99.77%N, 94.59%O, 99.73%W), feeding mostly on mesopelagic prey. Although common dolphins inhabit mainly coastal waters in the study area, the narrow continental shelf seems to facilitate the availability of Myctophids and other members of the mesopelagic assemblage to dolphins when the assemblage migrates to the surface at night. Our results represent the first attempt at quantifying the diet of this predator in the Alboran Sea and Strait of Gibraltar. 3: The ecological role of species can vary among populations depending on local and regional differences in diet. This is particularly true for top predators such as the bottlenose dolphin (*Tursiops truncatus*), which exhibits a highly varied diet throughout its distribution range. Local dietary assessments are therefore critical to fully understand the role of this species within marine ecosystems, as well as its interaction with important ecosystem services such as fisheries. Here, we combined stomach content analyses (SCA) and stable isotope analyses (SIA) to describe bottlenose dolphins diet in the Gulf of Cadiz (North Atlantic Ocean). Prey items identified using SCA included European conger (*Conger conger*) and European hake (*Merluccius merluccius*) as the most important ingested prey. However, mass-balance isotopic mixing model (MixSIAR), using *δ*13C and *δ*15N, indicated that the assimilated diet consisted mainly on Sparidae species (*e*.*g*. seabream, *Diplodus annularis* and *D*. *bellottii*, rubberlip grunt, *Plectorhinchus mediterraneus*, and common pandora, *Pagellus erythrinus*) and a mixture of other species including European hake, mackerels (*Scomber colias*, *S*. *japonicus* and *S*. *scombrus*), European conger, red bandfish (*Cepola macrophthalma*) and European pilchard (*Sardina pilchardus*). These contrasting results highlight differences in the temporal and taxonomic resolution of each approach, but also point to potential differences between ingested (SCA) and assimilated (SIA) diets. Both approaches provide different insights, *e* .*g*. determination of consumed fish biomass for the management of fish stocks (SCA) or identification of important assimilated prey species to the consumer (SIA). Article available at: https://www.researchgate.net/profile/Joan_Gimenez2 Best Regards, Joan -- *Joan Giménez Verdugo* *PhD Student* *Severo Ochoa* Estación Biológica de Doñana (EBD-CSIC) Department of Conservation Biology Americo Vespucio Ave, s/n 41092 Sevilla (Spain) www.ebd.csic.es --- Research Gate: Joan Giménez <https://www.researchgate.net/profile/Joan_Gimenez2> Phone: +34 619 176 849 ü Please consider the environment before printing this E-mail
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