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Rivers serve many societal functions and are one of the most intensively human influenced ecosystems worldwide, and, due to their importance, are included under the monitoring programs of the Water Framework Directive across Europe. Macroinvertebrates play an important role when monitoring running waters for the assessment of their environmental quality due to their reliability as bioindicators and utility in long-term studies. Macroinvertebrates do not constitute a systematic unit but they are formed by a set of different taxa, grouped according to taxonomic ranks, size and habitat preferences. They represent the base of the aquatic food chain, serving as a food source for amphibians, birds, reptiles, fish and humans, and contributing in the organic matter processing. Despite the large amount of data collected on Italian river macroinvertebrates and the increased interest in the study of this group, only few data are available for research scientist and managers. In this paper, we collected and homogenized knowledge on the presence, distribution and abundances of macroinvertebrates taxa inhabiting the River Po catchment (Northern Italy) in the last decade. The data set includes 130,727 records collected between 2007 and 2018 including 143 taxa of macroinvertebrates, mostly identified at family rank level. Moreover, the data set provides information on the geographic distribution of these families and their abundance by sub-catchment, altitude, meso- and micro-habitat.

The study of mammal acoustic communication was revolutionized hy the application of the source--filter theory, originally developed for human speech. The theory states that the vocal tract is constrained by body anatomy and, therefore, creates a structural link between phenotype and acoustic formants, providing a basis for honest signaling. The phenotype--formant link was validated in many species, but the phenotype--vocal tract link was rarely assessed. We used two dimensional (2D) videogrammetry to estimate the vocal tract length of wild southern elephant seal (Mirounga leonina (Linnaeus, 1758)) males during their normal vocalization behavior. We showed that (i) the vocal tract can be measured noninvasively in a large wild mammal; (ii) the vocal tract depends on the structural phenotype (age, body length, and skull size); (iii) the nasal tract is more related to the structural phenotype than the buccal tract; and (iv) the dependence on size, and body length in particular, is stronger than the dependence on age. Altogether, the phenotypic constraint on the vocal tract provides the anatomical basis for honest signaling in elephant seals. Key words: vocal tract, age, body length, skull size, vocalizations, source--filter theory, honest signaling, marine mammals, southern elephant seal, Mirounga leonina L'application de la théorie source--filtre, proposée à l'origine pour la parole humaine, a révolutionné l'étude de la communication acoustique chez les mammifères. Cette théorie postule que le tractus vocal est contraint par l'anatomie du corps et établit donc un lien structural entre le phénotype et les formants acoustiques, fournissant ainsi une base pour la signalisation honnête. Si le lien phénotype--formants a été validé chez de nombreuses espèces, le lien phénotype--tractus vocal a rarement été évalué. Nous utilisons la vidéogrammétrie bidimensionnelle (2D) pour estimer la longueur du tractus vocal d'éléphants de mer austraux (Mirounga leonina (Linnaeus, 1758)) mâles à l'état sauvage durant leur comportement de vocalisation normal. Nous démontrons que (i) le tractus vocal peut être mesuré de manière non invasive chez un grand mammifère à l'état sauvage, (iï) le tractus vocal dépend du phénotype structural (âge, longueur du corps et taille du crâne), (iii) le tractus nasal est plus étroitement relié au phénotype structural que le tractus buccal, (iv) la relation à la taille et la longueur du corps en particulier est plus forte que la relation à l'âge. Dans l'ensemble, la contrainte imposée par le phénotype sur le tractus vocal fournit le fondement anatomique de la signalisation honnête chez les éléphants de mer. [Traduit par la Rédaction] Mots-clés : tractus vocal, âge, longueur du corps, taille du crâne, vocalisations, théorie source--filtre, signalisation honnête, mammifères marins, éléphant de mer austral, Mirounga leonina, Introduction Acoustic signals may convey honest information about the emitter's phenotypic traits, such as body size or age, and can be used for assessment by the receiver (Taylor and Reby [...]

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.anbehav.2006.08.005 Byline: Simona Sanvito, Filippo Galimberti, Edward H. Miller Abstract: In the most common models of communication, it is assumed that animals provide reliable information about phenotype, and hence can settle competitive contests without physical interactions like fights. This assumption has rarely been tested for wild mammals. Recent studies of mammals have revealed relationships of vocal attributes to age and body size. Here, we analyse relationships of frequency attributes of agonistic vocalizations to phenotype (age, body size, proboscis size and agonistic behaviour) in males of the southern elephant seal, Mirounga leonina, a species with intense male competition for access to females, and in which vocalizations are used frequently to settle male-male contests. We analysed formant structure and vocal tract size, and found that nasal and oral components of the vocal tract contribute separately to vocal formants; hence, the male's proboscis serves to elongate the vocal tract. We also found that formants in the upper part of the frequency spectrum (fourth and fifth in particular) and formant dispersion convey significant information about age, size and resource holding potential at large, and, therefore, can be honest signals of a vocalizer's phenotype. Explained variance was statistically significant in our study and in similar studies but was not high, so formant structure cannot serve as the sole basis of acoustic assessment. Other possible sources of information exchanged in elephant seal contests are nonvocal acoustic signals (e.g. vibrations) and optical displays. Author Affiliation: (a) Department of Biology, Memorial University of Newfoundland, St John's, Canada (a ) Elephant Seal Research Group, Sea Lion Island, Falkland Islands Article History: Received 28 April 2006; Revised 30 June 2006; Accepted 10 August 2006 Article Note: (miscellaneous) MS. number: A10434

Abstract: The proboscis of male elephant seals (Mirounga Gray, 1827) has been suggested as an example of a secondary sexual trait since Darwin. There has been much speculation about its [...]

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.anbehav.2005.11.024 Byline: Anna Fabiani, Filippo Galimberti, Simona Sanvito, A. Rus Hoelzel Abstract: Southern elephant seals are highly gregarious during the breeding season, and both sexes show fidelity to the colony. We used microsatellite DNA analysis to assess kinship among seals in the main colony on the Falkland Islands. Specifically, we investigated whether females tend to cluster with close kin and avoid mating with male kin. We also tested expectations for kinship patterns based on sex differences in site fidelity and philopatry. Relatedness within a harem was significantly greater than between harems for only two of seven harems and was not related to harem size. Some long-term associations of female kin were found within harems, including associations of up to 5 years, but kinship among these females was not significantly higher on average than among dyads of other returning females. There was no pattern suggesting that females tended to choose harems with harem holders that were either more or less related to them than alternative harem holders. Overall, pairwise comparisons of females showed significantly greater kinship than pairwise comparisons of males, consistent with previous studies suggesting greater male dispersal. Author Affiliation: (a) School of Biological and Biomedical Sciences, University of Durham, U.K. (a ) Elephant Seal Research Group, Milano, Italy (a ) Department of Biology, Memorial University of Newfoundland, Canada Article History: Received 14 April 2005; Revised 13 July 2005; Accepted 11 November 2005 Article Note: (miscellaneous) MS. number: 8532R

The article discusses the integration of rapid invasive field estimation in assessing the body length of female elephant seals. Topics include the importance of body size estimation as a research component on foraging ecology, conservation and parental investment and the growing tendency in integrating noninvasive methods that based on photogrammetry in wildlife study. The various benefits of using photogrammetry-based methods in assessing the female elephant seals' body length are also noted.

The article presents a study that investigated the causes of death of northern elephant seal (NES) pups of the San Benito (SB) Islands in Baja, California, Mexico. The study involved marking pups and recovering the dead ones during the December 2006 to February 2007 breeding season, conducted postmortem examination of 21 dead pups, and revealed that female aggression and pup abandonment are the main causes of NES pup mortality of the SB colony.

The article discusses a study which shows that Phoca vitulina concolor 74 (Pvc74) is sex linked in both species of elephant seals, from genus Mirounga. The study used DNEasy Blood and Tissue kit to extract DNA from skin samples of Northern elephant seals (NES). The study found that harbor seals show a modest degree of sexual dimorphism and that sex detection in the field is not always easy.