Ricardo Bastida

• Marine Biology Researcher
• Professor Emeritus at National University of Mar del Plata

The Franciscana dolphin (Pontoporia blainvillei) is facing significant threats in the Southwestern Atlantic Ocean, largely due to entanglement in artisanal fishing nets, which makes it the most threatened dolphin species in the region Its conservation calls for a standardised methodology that enables the detection and monitoring of dolphin populati...

Quaternary glaciations severely altered landscape/seascape at high latitudes and had major consequences on species geographical ranges, population sizes, genetic differentiation and speciation rates. The Magellan province in southern South America, constitutes an interesting area to evaluate the effect of glaciations over near-shore marine benthic...

La acústica pasiva ha sido empleada para estudiar las vocalizaciones de los mamíferos marinos a distancia mucho mayores de las que pueden ser observadas, incrementándose así el conocimiento de la presencia, densidad y uso de hábitat (Sayigh 2014). Los cetáceos usan el sonido de manera activa y pasiva para comunicarse y explorar el ambiente, cubrien...

Ex situ options for cetacean conservation a d a w n o f h o p e c ri tically en d a n g e r e d e x t i n c t endang e re d v u ln erable

Sightings and strandings of humpback whales (Megaptera novaeangliae) along the coast of Buenos Aires Province in Argentina were once sporadic but have increased by up to 640% since 2018. Here, we assess the trends and seasonality of occurrence and anthropogenic-derived mortality in this population between 2003 and 2021. Most of the humpback whales...

Franciscana dolphin (Pontoporia blainvillei) is the most affected dolphin species in the Southwestern Atlantic Ocean. It is classified as Vulnerable A3D by IUCN and SAREM (national level) and only in northern coast of Argentina (Buenos Aires Province) around 400 dolphins are entangled every year in coastal gillnets. However, until now little is kno...

The biggest conservation problem that Franciscana dolphin (Pontoporia blainvillei) are facing nowadays is bycatch. In Argentina has been classified as Vulnerable (SAREM), under the IUCN criteria, and only in northern coast (Buenos Aires Province) around 400 dolphins entangled every year in coastal gillnets. The reason why this dolphin is entangled...

Our main interest is to detect the acoustic presence of franciscana dolphins in an area free of fishing pressure and then compare it with the detections made in areas with active bycatch. To meet that objective, two acoustic detectors (FPODS) were first placed in Chapadmalal (Free fishing zone) and then in two artisanal fishing gillnets in Claromec...

Groups of male South American sea lions (Otaria flavescens; SSLs) congregate in harbours on the northern coast of Argentina. These groups are very dynamic, with a high degree of habituation to human activities and the ability to colonise different types of artificial substrates, making them an interesting subject for understanding individual associ...

La ballena jorobada solía tener una presencia esporádica a lo largo de la costa de la Provincia de Buenos Aires (PBA), Argentina. A partir del año 2018 los avistamientos y varamientos han aumentado notablemente. El objetivo del presente trabajo es realizar una recopilación de los registros de ballena jorobada en la PBA, identificando: tendencias, e...

Understanding the role of marine mammals in marine ecosystems provides a context to assess the potential effect of depredation on their prey populations and the structure of communities. Moreover, it helps to figure out the impacts that prey populations suffer from fisheries and other anthropic activities. This understanding can help to foster a ra...

Male-only hauling grounds occur in close association to breeding colonies in several otariids. The occasional use of human-built infrastructure by these groups is also common. We observed permanent male aggregations of southern sea lions, Otaria flavescens, in urban contexts, such as two of the main fishing harbors in Argentina and investigated how...

The main aim of this work was to evaluate historical changes in the foraging ecology of Lahille's bottlenose dolphin (Tursiops truncatus gephyreus) along its distributional range. Stable isotopes of carbon (δ¹³C) and nitrogen (δ¹⁵N) were analyzed in bone samples from specimens deposited in scientific institutions from Brazil (BR), Uruguay (UY) and...

In 2003 Mycobacterium pinnipedii was described as responsible for producing tuberculosis (TB) in living otariid pinnipeds from Argentina and Australia. It is the only member of marine origin within the Mycobacterium tuberculosis Complex (MTBC), which also affects other domestic and wild mammals, and humans. Based on several pre-Columbian records of...

In 2003 Mycobacterium pinnipedii was described as responsible for producing tuberculosis (TB) in living otariid pinnipeds from Argentina and Australia. It is the only member of marine origin within the Mycobacterium tuberculosis Complex (MTBC), which also affects other domestic and wild mammals, and humans. Based on several pre-Columbian records of...

There are still unanswered questions about the centers of origin and the spread mechanisms of Tuberculosis (TB) throughout the population of different regions of the world. Molecular and immunological bone lesions studies in Southern Andes mummies indicate that TB was present in South America before the arrival of the Europeans. This work, set in a...

In South-western Atlantic waters, individuals of the southern right whale (SRW) Eubalaena australis spend part of the year (the austral winter and spring) in northern inshore waters where they breed and then migrate to southern feeding grounds during the summer. Mar del Plata (MDP) is located between two main reproductive areas (Península Valdés-Ar...

In Southwestern Atlantic waters, individuals of the southern right whale (SRW) Eubalaena australis spend part of the year (the austral winter and spring) in northern inshore waters where they breed and then migrate to southern feeding grounds during the summer. Mar del Plata (MDP) is located between two main reproductive areas (Península Valdés-Arg...

Communication in Porpoises (Cetacea: Phocoenidae) has been little studied. They usually produce narrow band high frequency clicks for echolocation, which have likely evolved to take advantage of a window of low ambient noise, and/or of the reduced hearing sensitivity of killer whales at these high frequencies (100+ kHz). Evidences for clicks emitte...

Bottlenose dolphins produce varied types of sound, including clicks, whistles, and bursts. We know that dolphins in nature have more click production at night during feeding activities and a peak occur at crepuscular/dawn hours, but dolphins in captivity are involved in several training/feeding sessions per day that are diurnal. To better understan...

La colección biológica del Grupo de Investigación “Biología, Ecología y Conservación de Mamíferos Marinos” del Instituto de Investigaciones Marinas y Costeras (IIMyC, UNMdP- CONICET, Argentina), reúne material óseo, diversos órganos, datos biométricos y fotográficos de mamíferos marinos colectados principalmente en la costa de la provincia de Bueno...

In Southwestern Atlantic waters, individuals of the Southern Right Whale (SRW) Eubalaena australis travel each year from their southern summer feeding grounds to their northern calving areas: Península Valdés (PV-Argentina) and Santa Catarina (SC-Brazil). The coast of Mar del Plata (MDP) is located between these two main reproductive areas. The pur...

Signature whistles are stereotyped and individually distinctive acoustic signals used as individual recognition calls, for maintaining group cohesion and during stressful situations. Here, it’s proved the occurrence of stereotyped whistles and how it changes, by an isolated adult female of short-beaked common dolphin (Delphinus delphis) kept in reh...

ABSTRACT Signature whistles are stereotyped and individually distinctive acoustic signals used as individual recognition calls, for maintaining group cohesion and during stressful situations. Here, it’s proved the occurrence of signature whistles and how it change, by an isolated adult female of short-beaked common dolphin (Delphinus delphis) kept...

ABSTRACT Signature whistles are stereotyped and individually distinctive acoustic signals used as individual recognition calls, for maintaining group cohesion and during stressful situations. Here, it’s proved the occurrence of stereotyped whistles and how it changes, by an isolated adult female of short-beaked common dolphin (Delphinus delphis) ke...

En el espacio intermareal del litoral marítimo argentino se localiza evidencia arqueológica de diverso origen. En este escenario costero intervienen factores ambientales específicos, generalmente más complejos que aquellos que ocurren en tierra o bajo el agua. Constituyen entornos dinámicos y ampliamente diversificados, por lo que el estudio del re...

Although bottlenose dolphins Tursiops truncatus are among the most common delphinid species, global population trends remain poorly understood. To improve the knowledge of the species in the Southwest Atlantic Ocean, thispaper reviews all available data related to the distribution and occurrence, abundance, residency and ranging patterns, group siz...

Although bottlenose dolphins Tursiops truncatus are among the most common delphinid species, global population trends remain poorly understood. To improve the knowledge of the species in the Southwest Atlantic Ocean, this paper reviews all available data related to the distribution and occurrence, abundance, residency and ranging patterns, group si...

Knowledge of growth patterns of an animal species is fundamental to understand their life history. This information is also used to help define population boundaries of threatened cetaceans, such as the Franciscana dolphin, Pontoporia blainvillei . A total of 108 Franciscana dolphins incidentally captured in artisanal fishing nets in estuarine and...

This catalogue lists the materials of marine mammals housed in the Mammalogical collection of Museo de La Plata. This contribution is an update of the unpublished catalogue made by R. Bastida, J.B. Desojo, and L.H. Soibelzon in 1997. It includes all the specimens deposited in this collection, belonging to the superorder Cetartilodactyla, order Ceta...

ABSTRACT. This catalogue lists the materials of marine mammals housed in the Mammalogical collection of Museo de La Plata. This contribution is an update of the unpublished catalogue made by R. Bastida, J.B. Desojo, and L.H. Soibelzon in 1997. It includes all the specimens deposited in this collection, belonging to the Superorder Cetartilodactyla,...

The Franciscana dolphin Pontoporia blainvillei is characterized by a long rostrum, a feature that is shared with the families formerly classified as river dolphins (Pontoporiidae, Platanistidae, Iniidae, Lipotidae). Although there are occasional reports on the existence of beak deformations, very little published information exists describing this...

Knowledge of the real size of any wild population is an essential tool to take management and conservation measures and even more so when the population studied may have potential conflicts with humans. Because of this, the objective of this study was to estimate the population size of two South American sea lion male haul-outs using mark-resightin...

Southern sea lions (Otaria flavescens; SSL) have a polygynous mating system and a prolonged social-sexual maturation period for males. Male haulouts are common in this species, with some very distant from central breeding rookeries, although the functions of these aggregations are not clearly understood. To estimate the potential connectivity betwe...

El objetivo de este trabajo es presentar los resultados de la revisión de la colección ósea de Mamíferos Marinos perteneciente a la Universidad Nacional de Mar del Plata (UNMdP) La revisión consistió en la cuantificación del material óseo de cetáceos y pinnípedos y su clasificación al menor nivel taxonómico posible. La información complementaria ta...

This article presents the results of a summer survey of marine mammal occurrence at the BrazilMalvinas Confluence in the Argentine Sea shelf break. A total of 61 marine mammal sightings were recorded. The most frequent species recorded were South American fur seals (Arctocephalus australis; 75.4%; 78-4670m),followed by sperm whales (Physeter macroc...

The present work describes the structure of benthic polychaete association of the southermost part of Samborombón Bay and its relationship with sediment after two decades of the last study made in the same area. Three sampling stations were established: Punta Rasa, Tapera de López and Arroyo San Clemente. Four species of polychaetes were identified...

ABSTRACT. Benthic polychaete association and their relationship with sedimentary parameters at south of Samborombón Bay (Buenos Aires province, Argentina): The present work describes the structure of benthic polychaete association of the southermost part of Samborombón Bay and its relationship with sediment after two decades of the last study made...

The ovaries of 31-franciscana dolphins (19 immature and 12 mature) by-caught in coastal waters of Argentina were examined to describe the reproductive biology. No ovarian polarity was found, both ovaries were functional and showed similar amount of corpora. A positive trend was observed between the number of corpora and age (3–8 yr old), indicating...

Nacella magellanica, the most abundant limpet in the Magellanic biogeographic Province of Argentina and Chile, is characterized by a noticeable variability in shell morphology and color patterns. Ecological as well as evolutionary features make this limpet an interesting species for evolutionary and population genetic studies. Here, arbitrary nucle...

Modern strains of Mycobacterium tuberculosis from the Americas are closely related to those from Europe, supporting the assumption that human tuberculosis was introduced post-contact. This notion, however, is incompatible with archaeological evidence of pre-contact tuberculosis in the New World. Comparative genomics of modern isolates suggests that...

The present study provides information about the diet composition of franciscana dolphin, Pontoporia blainvillei, from southern Buenos Aires coast, Argentina. From 2003 to 2011 we collected 66 franciscana dolphins that were incidentally entangled in artisanal fishing nets. We analyzed the stomach contents and estimated the prey size in order to eva...

Benthic monitoring programs can be used to investigate the relationship between shore birds and their intertidal food supply, and are particularly helpful in areas of rapid habitat fragmentation and deterioration resulting from human disturbance. Samborombon Bay in Buenos Aires Province, Argentina is an area of importance for migratory shorebirds t...

Hair bleaching marking technique in South American sea lions Otaria flavescens: Description and evaluation of method. The aim of this paper is to describe and evaluate the use of the hair discoloration method in South American sea lions, with an emphasis on its advantages and its potential use in future studies. For marking, stamp removable letters...

Beach debris, defined as solid waste materials of anthropogenic origin discarded at sea or reaching the sea through other ways, is one of the most highly visible expressions of human impact on the marine environment.

The Commerson’s dolphin (Cephalorhynchus c. commersonii, Lacépède, 1804) is the most common endemic dolphin of the coastal waters of Tierra del Fuego incidentally caught in artisanal coastal gill nets. A better understanding of its trophic ecology is essential to facilitate the effective management and conservation of its population. The aim of thi...

Birth, lactation, and maternal investment have been described and measured in many species of terrestrial and marine mammals that nurse their young on land such as pinnipeds, aquatic mustelids, and polar bears (Siniff & Ralls, 1991; Derocher & Stirling, 1995; Trillmich & Weissing, 2006). Because of their fully aquatic life cycle, information about...

The aim of this paper is to describe and evaluate the use of the hair discoloration method in South American sea lions, with an emphasis on its advantages and its potential use in future studies. For marking, stamp removable letters and numbers were used, connected to an extensible rod. The bleached marks obtained had a maximum duration of 347 days...

Resumen Por su particular dinámica, los sitios arqueológicos subacuáticos presentan características diferentes a aquellos localizados en tierra. Esto se debe en gran medida al rol fundamental que ejercen los sustratos del fondo en los ambientes acuáticos, tanto en lo que hace a los procesos de formación de sitio como a la conservación de los materi...

San Jorge Gulf, located in northern Patagonia, is characterized by extensive soft bottoms and large tidal ranges. A marine bot-tom section of 3 x 2 km, located off Caleta Olivia (Santa Cruz Province, Argentina) was sampled intensively during August 2008, covering a total of 35 oceanographic stations, with depths ranging from 25 to 48 m. Despite the...

a b s t r a c t At-sea behavior and effects of hydrographic conditions on the pelagic habitat use of South American fur seals (Arctocephalus australis) seasonally inhabiting the surrounding waters of shallow rocky reefs off Punta Mogotes (Mar del Plata, Argentina) were analyzed integrating geographic locations of fur seal groups (FSGs) with coastal...

We review the records of published and unpublished sightings and strandings for Risso's dolphin (Grampus griseus) in subantarctic waters of the Southwestern South Atlantic Ocean. Based on 59 sighting (n = 521 individuals) and 33 stranding records (n = 88 individuals), we identified three main areas of Risso's dolphin concentration in Patagonian wat...

We review the records of published and unpublished sightings and strandings for Risso's dolphin (Grampus griseus) in subantarctic waters of the Southwestern South Atlantic Ocean. Based on 59 sighting (n = 521 individuals) and 33 stranding records (n = 88 individuals), we identified three main areas of Risso's dolphin concentration in Patagonian wat...

We review the records of published and unpublished sightings and strandings for Risso’s dolphin (Grampus griseus) in subantarctic waters of the Southwestern South Atlantic Ocean. Based on 59 sighting (n = 521individuals) and 33 stranding records (n = 88 individuals), we identified three main areas of Risso’s dolphin concentration in Patagonian wate...

Permanent non-breeding Southern sea lion (Otaria flavescens) male rookeries are found in Mar del Plata (38º 02’ S, 57º 31’ W) and Quequén (38º 35’ S, 58º 42’ W) harbors in northern Argentina. These rookeries are located in an intermediate area between two main breeding sites (Uruguay and Patagonia) with a gap of 1,000 kilometers, and a significant...

The phylogeography of two sympatric Magellanic limpets of the genus Nacella was studied. The historical and contemporary processes underlying their intraspecific patterns in Argentina were inferred using the mitochondrial cytochrome oxidase I gene. Results indicate different evolutionary histories in the two species. A recent geographic and demogra...

resuMen A partir del análisis de 73 cráneos de Arctocephalus australis se deter-minó el patrón y orden de cierre de 12 suturas craneanas utilizando cuatro estadios de cierre sutural (1: sutura abierta, 2: sutura menos del 50 % cerrada, 3: sutura más del 50 % cerrada y 4: sutura cerra-da). Las suturas presentaron patrones de cierre diferentes según...

Aún persisten importantes interrogantes sobre los centros de origen y mecanismos de dispersión de la Tuberculosis (TB) a lo largo del poblamiento de las diversas regiones del mundo. Estudios moleculares e inmunológicos de lesiones óseas en momias de los Andes Meridionales indican que la TB estaba presente en América del Sur antes de la llegada de l...

Especialistas em Mamíferos Aquáticos da América do Sul (RT) 8º Congresso da Sociedade Latinoamericana de Especialistas em Mamíferos Aquáticos (SOLAMAC) Florianópolis (SC), 24 a 28 de outubro de 2010 Sociedade Latinoamericana de Especialistas em Mamíferos Aquáticos – SOLAMAC Several factors make the identification of stranded rorquals (Cetacea: Bala...

Introducción El origen y la antigüedad de la tuberculosis (TB) en el hombre ha sido motivo de intensos estudios y controversias por parte de la comunidad científica y fundamentalmente por los especialistas en paleopatología (Buikstra 1981; Santos 2000; Roberts y Buikstra 2003; Santos y Roberts 2006). Pese a que la TB está presente en América del Su...

Several species of the genus Nacella show high phenotypic intraspecific variability and only a few morphological characters can be used to identify them, so that their taxonomic status is unclear. In this work molecular markers were used to determine if the most frequent forms of the genus observed along the coast of Patagonia and Tierra del Fuego...

In marine mammals, the transition period between lactation and independent feeding provides an opportunity to evaluate the influence of the first solid food on heavy metal concentrations in their tissues at early stages of their life cycle. The aim of the present study was to compare mercury, cadmium, zinc and copper levels in lactating and recentl...

This paper describes the diet of the Red Knot (Calidris canutus) at Punta Rasa; the southern extreme of the Ramsar Site at Bahía Samborombón, in the Buenos Aires province, Argentina. Data presented here are mostly based on fecal analysis. We also used gizzard content analyses of four casualties that occurred during the catching operations. Remains...

Undaria pinnatifida was registered in Ría Deseado (47º45´S, 65º55´W - southern Patagonia) by the first time in spring 2005, colonizing the intertidal and shallow subtidal. A seasonal survey in 2006 showed that U. pinnatifida was established in a sheltered zone inside the estuary, along a coastal fringe of 8 km between Punta Cascajo and Cañadón del...

Undaria pinnatifida was registered in Ría Deseado (47°45′S, 65°55'W - southern Patagonia) by the first time in spring 2005, colonizing the intertidal and shallow subtidal. A seasonal survey in 2006 showed that U. pinnatifida was established in a sheltered zone inside the estuary, along a coastal fringe of 8 km between Punta Cascajo and Cañadón del...

The role of the benthic communities at Ría Deseado in the diet of the Patagonian blenny (Eleginops maclovinus) was analyzed in order to increase the understanding of the coastal food web in southern Patagonia. Subtidal benthic communities were surveyed between spring 2005 and autumn 2006 in areas of E. maclovinus sport fishing. Simultaneously, the...

A benthic survey was carried out from November 1998 to December 1999 in the tidal flats of Bahía Samborombón (Río de la Plata estuary, Argentina), in order to study the population structure, reproductive aspects, growth and secondary production of Capitella capitata (Fabricius, 1780). Growth was analyzed using ELEFAN routine, and the secondary prod...