Patagonian Coast Research Articles

Heteromorphic phases of Leathesia marina (Ectocarpales, Ochrophyta) over time from northern Patagonia, Argentina

:The emergence and evolution of the heteromorphic life history in algae has been considered as a response to the selective pressures of changing environments. The brown alga Leathesia marina has a typical heteromorphic life history, alternating between microscopic branched filaments (gametophytic phase) and a macroscopic erect stage (sporophytic phase). The first aim of this study was to describe vegetative and reproductive morphologies of sporophytes (macrothalli and diploid phase) of L. marina and their relationship with environmental factors in an annual cycle. The second aim was to report the discovery of gametophytes (microthalli and haploid phase) in the natural environment on northern Patagonian coasts, and to describe their morphology, abundance and reproductive output. The macroscopic phase was observed over 8 months, from September to April during the warm season. The microscopic phase was observed in two periods, March–April and September–October. A temporal overlap was observed between the microscopic and macroscopic phases. The population of macrothalli had a type III survivorship curve. The cover, density and size of macrothalli were associated with warmer months, but the abundance of microthalli and reproductive output of both phases were higher in temperate periods. Demographic parameters, including mortality rate, survivorship, reproductive output and the morphological characteristics of L. marina are used to evaluate the adaptation of this species to a changing environment, typical of the temperate coasts of northern Patagonia in Argentina.

Jesuits at Sea: José Quiroga and José Cardiel – Two Complementary Views of Patagonia (1745–1746)

Jesuit José Quiroga (1707–1784) was a naval officer and a navigator whose experience influenced his activity as a Jesuit. José Cardiel (1704–1781) was a Jesuit from a different educational and professional background. After sixteen years as a missionary among the Abipones and Guaraní, he joined forces with Quiroga, and they sailed the South Atlantic to have the adventure of their lifetimes. During 1745–1746, together with another Jesuit, Matthias Strobel (1696–1769), Cardiel and Quiroga led a maritime expedition along the Patagonian coast as part of an effort to expand the Jesuit missions in the region south of Río de la Plata. The final goal, however, was more ambitious: the exploration of Patagonia, the Strait of Magellan, and Cape Horn. A comparative analysis of Cardiel’s and Quiroga’s manuscript maps and their narratives offers two different but complementary views of Patagonia.

Development of the axial, paired and unpaired fin skeleton in three species of Patagonian zoarcids

Zoarcids are abundant in the intertidal zone of the Argentine Patagonian coast. However, their osteological development has not yet been described. Thus, the aim of this work is to describe the ontogeny of the axial skeleton and that of the paired and unpaired fins of the zoarcids Iluocoetes elongatus, Phucocoetes latitans and Dadyanos insignis. The three species studied showed a high degree of development at hatching and meristic counts coincide with those of the adults. At hatching, most of the structures showed that the appearance of bones was in progress. In the three species studied, this process occurred in a cephalo-caudal direction and, in most of the structures, the appearance of bones is observed from the middle to the rim.

Undercover speciation of wentletraps (Caenogastropoda: Epitoniidae) in the Southwestern Atlantic

Despite being one of the most speciose families, Epitoniidae still remains at present as one of the least understood gastropod families worldwide. This is a consequence of most of the species being only known from shell morphology, added to the wide intraspecific variability of this character and the fact that shell morphology has proven to have frequent examples of parallelisms and convergences among different (unrelated) species. Knowledge of other morphological and anatomical characters in this group is still in its first steps, and such information is currently available for a limited number of species, thus being difficult (when not impossible) to evaluate its taxonomic value. The aim of this study is to re-evaluate the diversity of Epitoniidae occurring in the Atlantic coast of Patagonia. As part of this study, the validity of only four of the six species described / reported from this area could be confirmed: Epitonium georgettinum, E. striatellum, E. fabrizioi and “Cirsotrema” magellanicum. In addition, three new species were recognized and are described herein: Epitonium evanidstriatum, “Cirsotrema” ctenodentatum and “Cirsotrema” strebeli. Information on the shell (including the protoconch), operculum, radula and jaw for these species is here provided, in most cases for the first time. A neotype for Scalaria magellanica is here designated. Furthermore, “Cirsotrema” georgeanum is here proposed as a replacement name for Scalaria fenestrata Strebel, 1908 (not Meneghini in de Stefani, 1875, nor Scalaria fenestrata Wöhrmann, 1889); and that taxon is regarded as a full species, instead of as a synonym of “Cirsotrema” magellanicum, as suggested in some previous publications. This study reveals that the usage of isolated (either morphological or anatomical) characters is usually insufficient for identifying some of the species from Patagonia; however, if these characters are combined, all species may be clearly recognized.

Mid-Holocene relative sea-level changes along Atlantic Patagonia: New data from Camarones, Chubut, Argentina

This paper concerns the relative sea-level changes associated with the Atlantic Patagonian coast derived from sea-level index points whose elevation was determined by a differential global position system (DGPS). Bioencrustations from outcrops located near Camarones, Chubut, Argentina, consist of autochthonous deposits characterized by Austromegabalanus psittacus (Molina, 1782), encrusting acervulinid foraminifera, coralline red algae and bryozoans. The association of the different organisms is interpreted as being associated with an intertidal environment, and they have been used as index points to establish the relative sea-level position. The main conclusion is that the relative sea-level between c. 7000 and 5300 cal. yr BP was in the range of c. 2–4 m a.s.l., with a mean value of c. 3.5 m a.s.l. Our data seem to support the existence of different rates of relative sea-level fall in different sectors of Atlantic Patagonia during the Holocene and highlight the importance of a more precise and accurate relative sea-level estimation by producing new data and revisiting the indicative meaning of most of the indicators so far used in the area.

Occurrence of bottlenose dolphins (Tursiops truncatus) in the Río Negro Estuary, Argentina, and their mid-distance movements along the northeastern Patagonian coast

A systematic study was carried out on bottlenose dolphins (Tursiops truncatus) in the Río Negro Estuary (RNE), Patagonia, Argentina, to analyze their occurrence and activity patterns in this region. The photo-identification data of this study was further compared to data from an adjacent region to gain information on the animals' movements along the northeastern Patagonian coast. Information was gathered through land-based observations between the months of March and July of 2008 up to 2011. Data on dolphin activity patterns were collected via an ad libitum focal-group sampling mode. At the same time, dorsal fin images were obtained from as many dolphins as possible for identification and subsequent re-identification of individuals. Total effort equaled 188h, resulting in 58h of observation of 124 dolphin groups [sightings per unit effort (SPUE) = 0.66 group/h]. Most of the groups observed contained between one and five individuals, and two main activity states could be determined, namely traveling (65%) and foraging (26%). The photo-identification effort, which started opportunistically in 2006, resulted in a catalogue of 17 individual dolphins, with a total mean re-identification rate of nine days (max. = 24 days). When comparing these pictures to the existing catalogue of Bahía San Antonio (BSA; approximately 200km west from the study area) dorsal fins of 15 individuals could be matched and most (n = 12) could be subsequently re-identified in both areas, indicating their long distance movements along the northeastern Patagonian coast during the austral autumn months. This season coincides with the lowest dolphin abundance and feeding activity in BSA. This study indicates that bottlenose dolphins enter the RNE to forage at least during autumn. It further suggests that the search for food resources is the main trigger for their movement patterns along the northeastern Patagonian coast during this season, at least for certain individuals. More research is needed to accurately confirm these hypotheses.

In Memoriam

In Memoriam

Sobre los objetivos y resultados de la expedición paleontológica de Handel T. Martin (1903-04) a la Formación Santa Cruz en Patagonia austral.

Entre enero y junio de 1904, Handel T. Martin (1862-1931), de la Universidad de Kansas (KU), colectó vertebrados fósiles de la Formación Santa Cruz (Mioceno temprano) a lo largo del Río Gallegos y la costa atlántica de Patagonia, como una iniciativa privada de Martin. En reporte de la expedición, Martin afirmó que cuando él y su compañero llegaron a Buenos Aires, visitaron a Florentino Ameghino en el (entonces) Museo Nacional. Su álbum de fotografías muestra que también visitó el Museo de La Plata y la casa de Ameghino en La Plata. Antes de dirigirse a la Patagonia, Martin organizó su equipo en Bahía Blanca, donde su hermano se había establecido. No hay certeza de si Martin recogió un total de 235 o 395 ejemplares. Claramente, su principal objetivo fue recoger fósiles para comercializar. Muchos especímenes fueron vendidos a instituciones en los Estados Unidos y Europa por Martin y Robert Ferris Damon, un comerciante de fósiles y minerales. Se han identificado cerca de 170 especímenes en colecciones formales. Gran parte de la colección - unos 130 de los mejores ejemplares - se mantuvo en KU, constituyendo una de las mayores colecciones de vertebrados santacrucenses fuera de Argentina (además de las del Museo Peabody de Yale en New Haven, el Museo Field de Chicago y el Museo Americano de Nueva York). Aunque la colección en KU es en gran medida ignorada por los paleontólogos y poco estudiada, contiene una buena representación de la fauna santacrucenses, con muchos ejemplares de calidad.

Raman spectroscopic analysis of archaeological specimens from the wreck of HMS Swift, 1770.

Specimens from underwater archaeological excavations have rarely been analysed by Raman spectroscopy probably due to the problems associated with the presence of water and the use of alternative techniques. The discovery of the remains of the Royal Navy warship HMS Swift off the coast of Patagonia, South America, which was wrecked in 1770 while undertaking a survey from its base in the Falkland/Malvinas Islands, has afforded the opportunity for a first-pass Raman spectroscopic study of the contents of several glass jars from a wooden chest, some of which had suffered deterioration of their contents owing to leakage through their stoppers. From the Raman spectroscopic data, it was possible to identify organic compounds such as anthraquinone and copal resin, which were empirically used as materia medica in the eighteenth century to treat shipboard diseases; it seems very likely, therefore, that the wooden chest belonged to the barber-surgeon on the ship. Spectra were obtained from the wet and desiccated samples, but several samples from containers that had leaked were found to contain only minerals, such as aragonite and sediment.This article is part of the themed issue 'Raman spectroscopy in art and archaeology'.

Larval digenean preferences in two sympatric snail species at differing tidal levels off the Atlantic coast of Patagonia.

Larval stages of the trematodes Maritrema madrynense and Hemiuroidea fam. gen. et sp. differentially parasitized Siphonaria lessonii and S. lateralis, two sympatric pulmonate snail species on the rocky intertidal shore at Puerto Deseado, south-western Atlantic coast of Patagonia, Argentina. Snail specimens were collected at two sampling sites with contrasting physical-chemical characteristics. One site, in the upper intertidal, was exposed to sewage from fish-processing plants, greater hydrodynamic forcing and desiccation, a wider temperature range, longer exposure to ultraviolet radiation and higher abundance of birds. The second site, in the lower intertidal, was generally characterized by less stressful environmental conditions. At both sites, S. lateralis showed a markedly higher density than S. lessonii (55.13 vs. 5.87 snails/m2, respectively). Despite this, the prevalence of both digeneans was higher in S. lessonii (17.37% and 3.52% for M. madrynense and Hemiuroidea, respectively) than in S. lateralis (0.09% and 0% for M. madrynense and Hemiuroidea, respectively). This study demonstrates high parasite specificity for the host. Low densities of S. lessonii are attributed to castration of parasitized hosts and reduction of their physiological condition. The prevalence and intensity of infection of both digenean parasites were higher at the more stressful, upper intertidal site, thus suggesting that a higher abundance of birds and exposure to sewage pollution may promote the transmission of trematodes.

Reintroduction strategy for the Andean Condor Conservation Program, Argentina

The Andean condor Vultur gryphus is the largest bird in the world with flight capacity. For thousands of years the Andean condor has been honoured as a sacred link between space and humans by indigenous communities. In the last 100 years, the range of this emblematic species contracted rapidly and the Andean condor was pronounced extinct at both ends of its endemic South American range, in Venezuela and on the Atlantic coast of Patagonia. The Andean condor appears in Appendix I of the Convention on International Trade in Endangered Species of Wild Fauna and Flora and is listed as in ‘Danger of Extinction’ by the United States Fish and Wildlife Service. In addition, according to the International Union for Conservation of Nature, this species is classified as Near Threatened. In 1991, the Andean Condor Conservation Program (PCCA: Programa Conservación Cóndor Andino) was founded in Argentina. The PCCA started by performing genetic analyses and documenting the condor population in zoological institutions in a Latin American regional studbook. The PCCA then developed artificial‐incubation programmes and techniques for hand rearing birds without human contact, and worked to rescue and rehabilitate wild condors. The PCCA has succeeded in rearing 57 chicks and rescuing 197 wild condors. This paper describes the strategy used by the PCCA to reintroduce 160 condors throughout South America.

Status of the names of some hydroid species (Cnidaria, Hydrozoa), described from the Atlantic coast of Patagonia.

Thirty new species of benthic leptothecate hydroids were described and named from Patagonia in a 1991 PhD dissertation by Mohamed El Beshbeeshy. Although constituting nomina nuda under provisions of the International Code of Zoological Nomenclature (ICZN), the names of some species were used in several scientific publications between 1991 and 2011. In 2011, the dissertation of El Beshbeeshy was published in accordance with Article 8 of the ICZN. Several species-group names appearing in that work nevertheless fail to fully comply with certain articles of the code. The goal of this contribution is to review the nomenclatural availability of the names of those 30 new taxa, and to clearly establish the current status of El Beshbeeshy's material. Two of them were made available in 1999 as part of studies other than those of El Beshbeeshy, and correct authorship and date is here noted. Twenty-one of the nomina nuda were made available in a work published by El Beshbeeshy in 2011, although some constitute junior synonyms. Six of the new species-group names appearing in both the 1991 and 2011 works, established following a literature review of Patagonian species, were proposed without re-description, or designation of name-bearing types, or locations of such types. Most of them do not meet criteria of availability and remain nomina nuda. The status of each is discussed to avoid additional nomenclatural errors and continued taxonomic confusion.

First record along the Uruguayan coast of the largest sea nettle jellyfish, Chrysaora plocamia (Lesson, 1830) (Cnidaria: Scyphozoa)

Chrysaora plocamia is one of the 15 species of the jellyfish genus Chrysaora. This species has an unusual distribution pattern, occurring on both Atlantic and Pacific coasts of South America. It is distributed along the southeastern Pacific Ocean, encompassing coastal areas of Peru and Chile, and reaching the Patagonian coast of Argentina in the southwestern Atlantic. During two separate events, two large specimens of Chrysaora were collected on the east coast of Uruguay at La Paloma. Based on morphology and molecular data, these specimens were identified as Chrysaora plocamia. These records are de­scribed along with oceanographic features observed at that time. Unusual oceanographic and atmospheric conditions may explain the presence of these specimens 1,100 km north of the current northernmost known distribution.

From Colonial Representation to Materiality: Spanish Settlements on the Valdés Peninsula, Patagonian Coast (1779–1810)

Fil: Buscaglia, Silvana. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Oficina de Coordinacion Administrativa Saavedra 15. Instituto Multidisciplinario de Historia y Ciencias Humanas; Argentina

Relaciones interétnicas en el Fuerte San José (Patagonia, siglo XVIII). Una aproximación comparativa

This paper present the first approach to the inter-ethnic relationships in the context of «San Jose» Fort and the «Puesto de la Fuente», from a historical and archaeological perspective. In particular, the first results of historical research about the problematic mentioned are introduced, based on unpublished data analyzed. The focus is over the first ten years of the fort (1779-1789) and a comparison is established with the other two settlements that were part of the Spanish colonization plan of the Patagonian coast (18th Century): «Nuestra Senora del Carmen» Fort and the «Nueva Colonia y Fuerte de Floridablanca», in order to highlight the peculiarity of San Jose Fort as part of the variability of the of inter-ethnic relationships estructuration at the Patagonian colonies.

The Role of Ancient Fishing on the Desert Coast of Patagonia, Argentina

ABSTRACTThis article explores latitudinal and chronological variations in the exploitation of marine fish by the hunter-gatherers who occupied the Atlantic coast of continental Patagonia, Argentina, since the mid-Holocene. Results indicate a spatial gradient in the importance of fish. A significant reduction in the frequency of fish remains in the archaeological sites occurs at higher latitudes. The chronological trends identified also suggest differences between the assemblages of the northern and southern coasts of this long littoral area. The results obtained are further discussed in relation to identified environmental and cultural variation.

New Results Concerning Expanded Networks of Obsidian Procurement in San Matías Gulf, Río Negro, Patagonia, Argentina

ABSTRACTIn this article we characterize the obsidian types present along the San Matías Gulf coast through geochemical analyses and we perform a techo-morphological analyses of the recovered artifacts. Also, we present a new obsidian type that has been found for the first time in the Atlantic coast of Patagonia. By this means we hope to better evaluate trends in the circulation and use of this raw material in the San Matías Gulf during the Middle and Late Holocene. As a result, we propose that there is a differential distribution between northern and southern Patagonia and among coastal sites (black and gray obsidians). This disparity could be mainly related to spatial distance, or to different mobility patterns of the human groups or to differential availability of the sources during the year. Growing evidence also suggests different raw material circulation.

GENETICS AND DEMOGRAPHY OF KELP GULLS IN PATAGONIA

The Kelp Gull (Larus dominicanus), a common seabird in coastal Patagonia, has recently increased in overall abundance and distribution, creating some concerns for the protection and conservation of other native, threatened species. We combined genetic and demographic data of four large Kelp Gull colonies distributed along 1800 km of the northern Patagonian coast of Argentina to further understand patterns of population growth and migration of the species. DNA analysis of variable intron sequences of two separate genes (myelin proteolipid protein, β-fibrinogen) revealed similar intra-colony levels of DNA sequence diversity. Pairwise FST comparisons revealed significant differentiation of the northernmost colony, Islote La Pastosa, from the two southern colonies, Punta Tombo and Isla Vernaci Sudoeste (p < 0.05). Indirect estimates of gene flow suggest significant mixing among colonies (Nm > 6). Demographic estimates revealed that Islote La Pastosa showed an increase in the number of breeding individuals over time (λ = 1.075), representing an area of potential population expansion. This is consistent with previous studies that have suggested that the demographic connectivity among Kelp Gull colonies in Patagonia may follow a source-sink dynamics, where growth rates of growing colonies are fuelled by the immigration of individuals from nearby colonies. The observed pattern also reflects the overall expansion of the species in the Patagonian region. This study suggests that proper management strategies for the Kelp Gull should take into account the genetic and demographic dynamics of this species.

New species of Chaetonema (Nematoda, Anoplostomatidae) and Admirandus (Nematoda, Oncholaimidae) from Patagonia, Río Negro and Santa Cruz, Argentina

Two new species are described from the Patagonia coast of Argentina, South Atlantic, and written keys to both genera are given. Chaetonema patagonica sp. nov. can most easily be differentiated from the other four species of the genus by the amphid shape and by the absence of a precloacal organ. Admirandus sanjuliensis sp. nov. is characterized by position of the Demanian pores, one preanal and two postanal, the configuration of pre- and postcloacal papillae and setae and by having the shortest stoma in the genus.

El procesamiento de ballenas varadas en las costas de la Patagonia occidental [a propósito de un grabado de mediados del siglo XIX

For canoe peoples of southernmost American, the stranding of a whale was “a great gift of nature”. The news of his presence, somewhere along the Patagonian coast, was transmitted very fast and people came from far places to share their products. In this paper we analyze the ethnographic information provided by a nineteenth-century engraving showing “an unusual yet ultimately practical way of carrying slippery blocks of whale blubber ashore”. The engraving was published by English novelist Thomas Mayne Reid in his Odd People (1860), but the original information is in the texts generated by the expeditions of HMS Beagle in Fuego-Patagonian coast between 1831 and 1836. We make some