Physiological toolkit to assess the health impacts on a Magellanic Penguin Spheniscus Magellanicus colony in a high-use touristic region of Patagonia, Argentina

We evaluated the health status of Magellanic Penguins Spheniscus magellanicus inhabiting a region on the Valdes Peninsula (Patagonia, Argentina) that is subject to extensive tourism. We compared individuals nesting along tour trails with others inhabiting non-touristic zones. Hematocrits, blood cell counts, glucose, cholesterol, total proteins, and heterophil/lymphocyte were considered as stress indices. Most parameters were not affected by tourism. Adults and chicks tested positive for bacterial pathogens in both the touristic and control areas. These data complemented a long-term database of systematic physiological monitoring on penguins and will be useful tools for future comparative analyses.Fil: D'Amico, Verónica L.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Centro para el Estudio de Sistemas Marinos; ArgentinaFil: Bertellotti, Néstor Marcelo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Centro para el Estudio de Sistemas Marinos; Argentin

RESIGHTINGS OF TWO-BANDED PLOVERS (CHARADRIUS FALKLANDICUS) DURING THE BREEDING SEASON IN COASTAL CHUBUT, PATAGONIA, ARGENTINA

Abstract · We report resightings of individually-marked Two-banded Plovers (Charadrius falklandicus) breeding in northern Patagonia across two consecutive seasons in two beaches separated by approximately 65 km in a straight line: Playas Blancas (Península Valdés) and Playa Paraná (Puerto Madryn), Chubut province, Argentina. We captured and banded 24 adults at the nest while incubating during 2016. Nineteen banded individuals (ca. 80%) were resighted in 2017, 17 on the same site where they were banded, while 2 moved between survey sites. Only 32% were found breeding again while the remaining 68% were resighted resting or foraging, solitarily or in mixed flocks with other shorebird species. Among the resighted breeders, two adults were found paired with a different banded partner as in the previous year. The remaining breeders were paired with unbanded partners, and hence mate fidelity could not be assessed. Our findings add information to the scarce data on the breeding biology of this species suggesting that Two-banded Plovers exhibit site fidelity.Resumen · Avistamientos de Chorlos Doble Collar (Charadrius falklandicus) durante el período reproductivo en la costa de Chubut, Patagonia, Argentina Presentamos avistamientos de Chorlos Doble Collar (Charadrius falklandicus) anillados en dos playas de la provincia de Chubut, Argentina: Playas Blancas (Península Valdés) y Playa Paraná (Puerto Madryn) separadas entre si aproximadamente 65 km en línea recta. En la temporada 2016, se capturaron y anillaron 24 individuos adultos durante la incubación. La mayoría de ellos (19, ca. 80%) fueron avistados en la temporada 2017, 17 en el mismo sitio donde fueron anillados y 2 en el otro sitio de estudio. El 32% se observó anidando mientras que, el 68% restante, se observó en el área descansando o alimentándose en forma solitaria o en bandadas mixtas con otras especies de aves playeras. Entre los individuos reproductores en 2017, dos anidaron con parejas también anilladas aunque diferentes al año anterior. Los reproductores restantes se observaron con parejas no marcadas, por lo que no se pudo evaluar si estaban apareados con el mismo individuo que en la temporada anterior. Estos resultados aportan nuevos datos sobre la biología reproductiva de esta especie que se suman a los estudios previos en la zona, sugiriendo que los Chorlos Doble Collar muestran fidelidad al sitio reproductivo

Antihelminthic treatment alters cellular, but not humoral immune components in Magellanic penguin (Spheniscus magellanicus Forster, 1781) chicks

We evaluate whether helminth parasites affect both cellular and humoral components of the immune system of Magellanic penguin (Spheniscus magellanicus Forster, 1781) chicks. We measured immune components after the administration of an antihelminthic drug to remove parasites. Cellular immune components included the complete white blood cell count (WBC) and the in vivo skin-swelling response to phytohemagglutinin (PHA). Humoral aspects assessed were the ability of plasma to agglutinate foreign particles and the bactericidal capacity of plasma. Antihelminthic treatment resulted in lower total WBC counts supporting the role of circulating leukocytes in fighting macroparasites. Deparasitized chicks showed a reduction in all types of leukocytes. Contrary to our expectation deparasitized Magellanic penguin chicks showed lower response to PHA injection than control chicks. The swelling response was positively correlated with body condition and with total WBC in circulation. We hypothesize that the specific helminth community naturally occurring in Magellanic penguin chicks might have an overall immunostimulatory effect on the PHA response. Antihelminthic treatment did not alter the innate humoral immune parameters measured. Our results support the prediction that, given their relatively low costs of use and maintenance, innate humoral components would not be as affected by antihelminthic treatment as more costly cellular responses.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author

Effects of antihelminthic treatment on cell-mediated immunity in Gentoo penguin chicks

Intestinal parasites suppose a cost to hosts as they compete directly for nutritional resources. Therefore, hosts must defend themselves against intestinal parasites by mounting an immune response. Many penguin species acquire parasites through their diet and transfer these parasites to their chicks when feeding them. High parasite loads in penguin chicks could have effects on their growth and body condition, and ultimately on their survival. Here, we evaluated the effect of parasites on the cell-mediated immune system in Gentoo penguin (Pygoscelis papua) chicks at Stranger Point (25 de Mayo/King George Island, South Shetland Islands). To this end, 12 chicks were experimentally deparasitized with a mixture of anthelminthic drugs (albendazole and praziquantel), whereas 10 others were kept as control. We measured cutaneous cell-mediated immunity in response to immunization with phytohemagglutinin (PHA). We also analyzed the leukocyte profile in both treated and control groups before and after the treatment. After the treatment, deparasitized birds showed larger foot-web swelling in response to PHA injection than control birds. Deparasitized penguins also showed lower eosinophil and monocyte counts than controls, whereas heterophils, lymphocytes, and total white blood cell counts did not differ between groups. Our results suggest that Gentoo penguin chicks parasitized with intestinal parasites suffer a cost in terms of reduced cell-mediated immune responses that could ultimately affect their survival.AB was supported by the Project CTM2011-24427 funded by the Spanish Ministry of Economy and Competitiveness.Peer Reviewe

Physiological differences between two overlapped breeding Antarctic penguins in a global change perspective

This article is an invited contribution on Life in Antarctica: Boundaries and Gradients in a Changing Environment as the main theme of the XIth SCAR Biology Symposium. J.-M. Gili and R. Zapata Guardiola (Guest Editors).Global change has affected the Antarctic Peninsula influencing the abundance of krill, one of the main preys of penguins. In areas where breeding penguin populations overlap, species with a more diverse diet have generally been less affected than krill-specialist species, which have shown population declines. Human activities can add to these changes, as penguins are sensitive to anthropic impacts such as contamination. Our objective was to assess whether selected physiological parameters of Adélie and Gentoo penguins reflect their contrasting population trends in a colony located at Punta Stranger (25 de Mayo Island/King George, South Shetland Islands) where they breed sympatrically. During 2012, we assessed the leukocyte profile, heterophil to lymphocyte ratio (H/L), erythrocytic nuclear abnormalities (ENAs), hematocrit, biochemical profile, and a measure of immune function (bacterial agglutination) in adults and chicks of both species. Higher values of ENAs, indicative of genotoxic damage caused by contaminants, are in accordance with a greater sensitivity to ongoing global changes by Adélie penguins. Levels of cholesterol and triglycerides strengthen this idea since individuals could be investing more resources in energy reserves to successfully cope with challenging environmental conditions during the breeding season. The remaining physiological parameters did not provide a clear picture. Furthermore, some results could be related to differences in diet. Gentoos show greater prey diversity than Adélie penguins, incorporating a richer parasite fauna, which could explain their higher heterophils and H/L. The physiological parameters measured here serve as baseline for a sustained monitoring of these rapidly changing populations. Further physiological variables, including stress hormone and indices of oxidative stress, remain to be assessed as potential indicators of population susceptibility to global change in this system.AB was supported by the project CTM2011-24425.Peer Reviewe

Kelp gulls attack Southern right whales: a conservation concern?

Kelp gulls (Larus dominicanus) feed on pieces of skin and blubber they rip from Southern right whales’ (Eubalaena australis) backs in their breeding areas at Península Valdés, Argentina, producing injuries. This behavior has increased since the first record in 1972, and some authors have suggested that constant gull harassment could have a negative effect on right whale population. The main goal of this study is to assess the variables that most affect the gull attacks. We analyzed 5359 whale-watching sightings made during trips from Puerto Pirámides (42º34′S, 64º16′W) along the whale breeding seasons (June–December) 2005 to 2007. The most important factors affecting the attacks include the presence of a mother–calf pair, the time within the season, the distance to the coast and the wind velocity. There is also concern of possible transmission of infectious diseases in the attacks since increasing number of whales with different patterns of skin lesions have been observed.Fil: Fazio, Ana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; ArgentinaFil: Bertellotti, Néstor Marcelo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; Argentina. Wild Earth Foundation; ArgentinaFil: Villanueva, María Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; Argentin

In vitro effects of lead ions on peripheral benzodiazepine receptors and adenylyl cyclase activity in the mantle of Mytilus galloprovincialis

As an extension of our previous work, where the density of peripheral benzodiazepine receptors (PBR) increased in mantle mitochondria of the marine mollusk Mytilus galloprovincialis Lmk. under chronic exposure to lead, the present study investigates the in vitro effects of an exogenous source of lead ions on PBR and on adenylyl cyclase (AC) complex in mantle membranes of mussels collected from a non-polluted coastal area. PBR binding experiments used the specific isoquinoline carboxamide derivative [H-3]PK 11195, and AC activity was measured using a modified procedure adapted to M. galloprovincialis. Lead ions (Pb2+) dose-dependently decreased either the [H-3]PK 11195 specific binding in mitochondria or basal AC velocity in plasma membranes of mussel mantle. The IC50 values for lead ions were 10 muM with [H-3]PK 11195 binding and 25 muM with AC activity, with maximal inhibition values of 60% and 70%, respectively. Moreover, lead behaved as a non-competitive inhibitor on [H-3]PK 11195 binding and as a 'mixed' inhibitor on AC activity The present results suggest that some of the early effects induced by lead in mussel cell metabolism consist in significant changes of the PBR density and cyclic AMP production in the mantle of M. galloprovincialis. (C) 2004 Elsevier Inc. All rights reserved