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Copyright of Journal of Neotropical Mammalogy / Mastozoologia Neotropical is the property of Sociedad Argentina para el Estudio de los Mamiferos and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The present work documents the stratigraphic distribution of dinoflagellate cysts from the upper part (60–585 m) of the YPF.Ch. PV. es-1 borehole, Península Valdés, Argentina. The assemblages exhibit a relatively moderate to low diversity. Most samples are characterized by frequent to abundant taxa of the order Gonyaulacales, such as Spiniferites/Achomosphaera spp., Reticulatosphaera actinocoronata, Operculodinium centrocarpum, and Melitasphaeridium choanophorum. Furthermore, a continuous succession of Early Miocene–Late Miocene diagnostic dinoflagellate cyst events was recorded for the first time from the Península Valdés region. Eight diagnostic events of highest occurrences (HOs) of dinoflagellate cyst taxa are identified. These bioevents allowed a subdivision of the sedimentary succession into two well-defined stratigraphic sections: Early to Middle Miocene (Burdigalian–Langhian/probably Serravalian, 430/425–330/325 m) based on the HOs of Emmetrocysta urnaformis, Cannosphaeropsis quattrocchiae, Cousteaudinium auybriae, and Cleistosphaeridium ancyreum, and Late Miocene (Tortonian–Messinian, between 175–170 and 80/85 m) based on the HOs of Labyrinthodinium truncatum subsp. truncatum, Operculodinium piaseckii, and Reticulatosphaera actinocoronata. The ranges of these taxa are compared with well-documented information on Neogene dinoflagellate cysts recorded from different sites across the North and South Atlantic Ocean and adjacent seas. In general, the dinoflagellate cyst assemblages, as well as the selected diagnostic taxa, exhibit a clear similarity to those of the Northern Hemisphere. The only exception is Hystrichokolpoma rigaudiae, which is asynchronous, possibly indicating local paleoenvironmental conditions. [ABSTRACT FROM AUTHOR]

The southern elephant seal, Mirounga leonina, is one of the top predators inhabiting the Southern Ocean. Foraging at sea represents 80% of their annual cycle, during which they make extraordinary wide-ranging trips with long, deep, and continuous dives. Their feeding habits have been broadly studied using both traditional and advanced techniques, like stable isotope analysis. Here, we analyzed stable isotope ratios of C and N of host and sucking lice tissues to investigate the potential use of lice to infer the isotopic patterns of their host at a major scale while using a less invasive method. We collected samples of blood and lice, Lepidophthirus macrorhini, from 15 weaned pups in Península Valdés (Chubut, Argentina). C and N isotopic signals of lice and pups were correlated. The δ13C values of the lice were not different from those of their hosts, while the δ15N signals were statistically significantly enriched with respect to those of the pups. The isotopic composition of the lice would predictably mirror that of their hosts. However, the values of Δ13C and Δ15N (difference between lice and pup signals) differed from the literature-based reference values for hematophagous ectoparasites, indicating that lice could have changed the host recently or that the residence time in the pups has not been enough. Given that mothers and weaned pups differ isotopically due to lactation, the isotopic composition of lice could therefore be more representative of signals from females, implying a useful and a safe tool for identifying and measuring the magnitude of trophic interactions in this species. [ABSTRACT FROM AUTHOR]

Copyright of APUNTES - Journal of Cultural Heritage Studies is the property of Pontificia Universidad Javeriana and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Elephant seals, Mirounga spp., are highly dimorphic, having different energetic requirements according to age and sex, and foraging in various ecological and oceanographic contexts. Resource partitioning has been shown for the sub‐Antarctic populations of southern elephant seals, M. leonina, where colonies are surrounded by narrow shelves that deepen abruptly. In contrast, seals from Península Valdés (Argentina), in the northernmost extent of the breeding range, face an extended, shallow, temperate, and productive continental shelf. We integrated tracking data from 98 animals (juveniles and adults, males and females) gathered over more than two decades, and found that although all available habitats were used, individuals segregated by age and sex. Juvenile males favored shelf habitats, whereas subadult and adult males also used the shelf break. Juvenile females preferred the shelf and the more distant Argentine Basin used by postbreeding and postmolt adult females. Males showed the highest proportion of area‐restricted search locations, suggesting more spatially concentrated feeding activity, and likely reflecting a preference for foraging habitat and prey. Our results are consistent with those from other populations, implying that elephant seals show remarkable similarities in habitat use by age and sex classes, despite broad differences in the offshore habitats between sub‐Antarctic and temperate ecosystems. [ABSTRACT FROM AUTHOR]

Anisakid nematodes have a worldwide distribution and are associated with fishes, birds, and marine mammals from freshwater, brackish, and marine systems. The aims of this work are to report for the first time Contracaecum mirounga parasitizing the Magellanic penguin Spheniscus magellanicus, to report another Contracaecum species in the same host species, and to discuss the validity of Contracaeceum spheniscus. Several dead chicks, juveniles, and adults of S. magellanicus were collected along the Argentinean coast from 2002 to 2009. Nematodes were removed from digestive tracts and studied using both light and scanning electron microscopy. Nematode prevalences were 2.38% for C. mirounga and 12.5% for Contracaecum sp. Contracaecum mirounga was found in 1 penguin from Península Valdés, Chubut. This species is known as a specific parasite of marine mammals such as Pinnipedia, thereby suggesting that this nematode is not as specific as believed. Another species of Contracaecum sp. was found parasitizing 1 penguin from the Río de la Plata coast. It possessed an unusual interlabial morphology and arrangement of male caudal papillae. Despite the low prevalence, the distinct morphological features are convincing and support the presence of a new Contracaecum species. However, a formal description is not presented because sufficient male specimens are lacking. Finally, C. spheniscus is considered a junior synonym of Contracaecum pelagicum. Future molecular studies might be helpful to determine the real diversity of Contracaecum species parasitizing S. magellanicus considering the number of sibling species recognized among the anisakids. [ABSTRACT FROM AUTHOR]

Across modified landscapes, anthropic factors can affect habitat selection by animals and consequently their abundance and distribution patterns. The study of the spatial structure of wild populations is crucial to gain knowledge on species' response to habitat quality, and a key for the design and implementation of conservation actions. This is particularly important for a low-density and widely distributed species such as the mara (Dolichotis patagonum), a large rodent endemic to Argentina across the Monte and Patagonian drylands where extensive sheep ranching predominates. We aimed to assess the spatial variation in the abundance of maras and to identify the natural and anthropic factors influencing the observed patterns in Península Valdés, a representative landscape of Patagonia. We conducted ground surveys during the austral autumn from 2015 to 2017. We built density surface models to account for the variation in mara abundance, and obtained a map of mara density at a resolution of four km2. We estimated an overall density of 0.93 maras.km-2 for the prediction area of 3,476 km2. The location of ranch buildings, indicators of human presence, had a strong positive effect on the abundance of maras, while the significant contribution of the geographic longitude suggested that mara density increases with higher rainfall. Although human presence favored mara abundance, presumably by providing protection against predators, it is likely that the association could bring negative consequences for maras and other species. The use of spatial models allowed us to provide the first estimate of mara abundance at a landscape scale and its spatial variation at a high resolution. Our approach can contribute to the assessment of mara population abundance and the factors shaping its spatial structure elsewhere across the species range, all crucial attributes to identify and prioritize conservation actions. [ABSTRACT FROM AUTHOR]

This paper reports on aerial surveys conducted to estimate the relative abundance and trend in growth of the southern right whale (Eubalaena australis) population from Península Valdés. The number of whales counted tripled from 1999 to 2016. We modeled the number of whales, the number of calves, the number of solitary individuals and the number of individuals in breeding groups using as predictive variables the year, Julian day, and Julian day2 by means of generalized linear models. The rate of increase decreased from near 7% in 2007 to 0.06% and 2.30% for total number of whales and number of calves, respectively for 2016. Trends in the rates of increase for total number of whales and number of calves were negative (−0.732% and −0.376%, respectively). The habitat use of the whales changed along the years, with mothers and calves using more heavily the near‐shore strip, resulting in a decreasing trend for solitary individuals and breeding groups in near‐shore waters. We conclude that whales are still increasing their abundance, while the rate of increase is decreasing. Differences in the rates of increase of the group types and changes in habitat use are thought to be the consequence of a density‐dependence process. [ABSTRACT FROM AUTHOR]

Background: The Southern Right Whale (Eubalaena australis) population of the South–western Atlantic Ocean is recovering. In the breeding ground of Peninsula Valdés, as a consequence of the population growth, expansion to new areas by some types of groups and a change in the habitat use patterns at the coastal area were recorded. Methods: We analysed information gathered from aerial surveys conducted along the coast of Peninsula Valdés in 15 years of effective sampling in a 19-year span. These surveys were divided into four periods (1999–2000; 2004–2007; 2008–2012 and 2013–2016) and estimated the density of whales in a 620 km of coast divided into segments of five km. Results: The density of the whales increased to near three whales per km² (averaged over each period) in the high-density areas. When this mean number was reached, the significant changes in density in the adjacent areas were detected in the following period. These changes were a decrease in density in the high-density areas and an increase of density in the low-density areas. Discussion: We propose that a threshold in density elicits a response in habitat use, with the Mother-calf pairs remaining in the area, while the other groups are displaced to new areas. [ABSTRACT FROM AUTHOR]

Península Valdés ( PV) in Argentina is an important calving ground for southern right whales ( SRWs, Eubalaena australis). Since 2005, right whale mortality has increased at PV, with most of the deaths (~90%) being calves <3 mo old. We investigated the potential involvement of harmful algal blooms ( HABs) in these deaths by examining data that include: timing of the SRW deaths, biotoxins in samples from dead SRWs, abundances of the diatom, Pseudo-nitzschia spp., and the dinoflagellate, Alexandrium tamarense, shellfish harvesting closure dates, seasonal availability of whale prey at PV and satellite chlorophyll data. Evidence of the whales' exposure to HAB toxins includes trace levels of paralytic shellfish toxins ( PSTs) and domoic acid ( DA) in tissues of some dead whales, and fragments of Pseudo-nitzschia spp. frustules in whale feces. Additionally, whales are present at PV during both closures of the shellfish industry (due to high levels of PSTs) and periods with high levels of Pseudo-nitzschia spp. and A. tamarense. There is a positive statistical relationship between monthly Pseudo-nitzschia densities (but not A. tamarense) and calf deaths in both gulfs of PV. [ABSTRACT FROM AUTHOR]

Copyright of Intersecciones en Antropología is the property of Universidad Nacional del Centro de la Provincia de Buenos Aires, Facultad de Ciencias Sociales and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

ABSTRACT Penguin colonies are highly visited worldwide. Although several studies have addressed how penguins behaviorally respond to tourist visitation at a point in time, nothing is known about their response across the entire breeding season. Furthermore, behavioral responses are driven by complex physiological processes and the basal physiological state of the individual might affect the way it responds to stimuli. To test the hypothesis that annual changes in corticosterone result from animals having different requirements for expressing (or not) the glucocorticoid-mediated behaviors at different times of the year in the context of tourist visitation, we examined circulating and stress-induced corticosterone in Magellanic penguins ( Spheniscus magellanicus) from non-visited areas from the San Lorenzo colony, Peninsula Valdes, Argentina across the breeding season. We also examined the behavioral responses of penguins to a pedestrian approach in tourist-visited and non-visited areas of the colony across the season. Our results showed that circulating levels of corticosterone did not vary across the season; however, stress-induced corticosterone was lowest during molt. Our behavioral results showed that penguins displayed different behavior responses at varying distances depending on the area (visited or non-visited) and stage in the season. Penguins in the tourist area were more tolerant to a human approach than penguins in the non-tourist area. During settlement and molt, penguins showed higher occurrence of behaviors related to self-survival (such as standing, moving farther into the nest, and fleeing), whereas during incubation and chick rearing, penguins displayed mostly a behavior associated with defense and vigilance (such as alternate head turns). Furthermore, penguins allowed a closer approach during incubation, but elicited a subsequent behavior quicker than in the rest of the stages, suggesting that they would be particularly sensitive in this stage. Overall, our results suggest that corticosterone release across the season is more associated with penguins' survival in an extreme environment than with behavioral regulation. From a conservation perspective, we identified that penguins were more sensitive to human approach during incubation, but also molt should be considered as a vulnerable stage because corticosterone secretion is suppressed. © 2014 The Wildlife Society. [ABSTRACT FROM AUTHOR]

The objective of this study was to describe associations between several species of seabirds and dusky dolphins. We investigated during what dolphin activities seabirds were most commonly associated, and the size of flock in relation to the number of dolphins in a group. Since both seabirds and dolphins may display different feeding strategies, we also investigated if benefits differed among seabird species. Data were collected in Golfo Nuevo (42°20′S65°00′W) on-board a research vessel between 2001 and 2008. A total of 224 mixed groups of seabirds were encountered during this study. The seabird–dolphin associations were mainly observed during dusky dolphin surface feeding. Shearwaters and kelp gulls were mainly observed in flocks that were associated with dolphins, while Magellanic penguins and cormorants were mainly observed without dolphins. Seabirds may be conditioned to the foraging strategy of dolphins, since birds are associated with dolphins only during dolphin surface feeding. This association probably helped seabirds to find prey, but there were no obvious benefits to dolphins. [ABSTRACT FROM PUBLISHER]

The Natural Protected Area Peninsula Valdés, located in Northeastern Patagonia, is one of the largest conservation units of arid lands in Argentina. Although this area has been in the UNESCO World Heritage List since 1999, it has been continually exposed to sheep grazing and cattle farming for more than a century which have had a negative impact on the local environment. Our aim is to describe the first dataset of tenebrionid beetle species living in Peninsula Valdés and their relationship to sheep grazing. The dataset contains 118 records on 11 species and 198 adult individuals collected. Beetles were collected using pitfall traps in the two major environmental units of Peninsula Valdés, taking into account grazing intensities over a three year time frame from 2005-2007. The Data quality was enhanced following the best practices suggested in the literature during the digitalization and geo-referencing processes. Moreover, identification of specimens and current accurate spelling of scientific names were reviewed. Finally, post-validation processes using DarwinTest software were applied. Specimens have been deposited at Entomological Collection of the Centro Nacional Patagónico (CENPAT-CONICET). The dataset is part of the database of this collection and has been published on the internet through GBIF Integrated Publishing Toolkit (IPT) (http://data.gbif.org/datasets/resource/14669/). Furthermore, it is the first dataset for tenebrionid beetles of arid Patagonia available in GBIF database, and it is the first one based on a previously designed and standardized sampling to assess the interaction between these beetles and grazing in the area. The main purposes of this dataset are to ensure accessibility to data associated with Tenebrionidae specimens from Peninsula Valdés (Chubut, Argentina), also to contribute to GBIF with primary data about Patagonian tenebrionids and finally, to promote the Entomological Collection of Centro Nacional Patagónico (CENPAT- CONICET) and its associated biodiversity data. For these reasons, we believe that this information will certainly be useful for future faunistic, ecological, conservational and biogeographical studies. [ABSTRACT FROM AUTHOR]

This paper reports on sightings and dispersion of individual southern elephant seals (Mirounga leonina) along the Atlantic and Pacific coasts of South America based on reports of tagged/marked seals from Patagonia and of animals of unknown origin. From 154 sightings, encompassing at least 354 individuals, we found that individuals dispersed to subequatorial latitudes on both sides of the continent, and to more temperate sites, in the Magellanic region of Tierra del Fuego. Nineteen sites were visited by tagged seals from the established colony of Peninsula Valdés (PV, Argentina). PV and the smaller seal population of the Falklands/Malvinas were regularly connected by adults of both sexes. There were more sightings of males than females. No incipient new breeding colonies were found along the Atlantic coast of South America. Some observations coincided with places where elephant seals had been recorded or exploited in the seventeenth and eighteenth centuries. A shortage of suitable habitat for expansion and proximity to predictable food could act as a stabilizing process preventing colonization of new areas from PV. Dispersion data, coherent with population genetics, support a Patagonian elephant seal stock. [ABSTRACT FROM AUTHOR]

The development of software able to provide individual recognition of southern elephant seals, as a tool to study colonies. This analysis was performed within a framework of studies concerning environmental dispersion produced by the El Niño Southern Oscillation effect in the Southern Ocean Ecosystem. Digital photographs of reproductive female elephant seals were taken at Punta Norte (Península Valdés, Patagonia; 42°05′ S, 63°45′ W) during the 2002 breeding season (August to November). The data set under analysis is composed of 96 elephant seal images for a population of 56 individuals. Identification of specimens was carried out using digital pictures taken with a digital video camera, and processed through the‘ Eigenfaces’ method, which is based on principal components analysis. Special care was taken to control possible variations among images of the same individual, like distance, angle, light intensity, etc. To deal with these variations, an initial alignment procedure is proposed to have all images framed; in addition an initial histogram equalization was used which attenuates any potential variation in light intensity. The software was developed in IDL5.5 language. A complete set of empirical results is displayed showing the potential effectiveness of this technique. Individual recognition and pertinence to different population subsets (harems) tests have been carried out. A principal result of this work is that all 96 elephant seal images (representing 56 individuals) were correctly identified. The Eigenfaces method can be used successfully for identification of elephant seals. With the appropriate preparatory treatment of images, high performance results can be expected. [ABSTRACT FROM AUTHOR]

The study describes the annual cycle of southern elephant seals for the increasing colony of Peninsula Valdés, and compares it to the haul-out pattern reported for stable or decreasing sub-Antarctic colonies of the species. Data were collected during censuses of the entire colony (nine breeding seasons, two moulting seasons and one autumn--winter haul-out), monthly surveys of coastline and mark-recapture of pups. Pup production during the study period grew from 12 113 to 14 621 animals (1995-2003). Most relevant events of the cycle were similar for all colonies studied, independent of the geographical location, size or population trend. Compared with other locations where southern elephant seals breed and moult, distinct features for Peninsula Valdés were: i) breeding occurs earlier in the spring, and ii) most adult females reproduce and moult in the same colony. The increasing number of animals ashore was correlated with the expansion in pup production. Population trends and stability of demographic events could be related to a consistent physical environment (ocean fronts) during foraging phases of the annual cycle. [ABSTRACT FROM AUTHOR]