Miguel Motas

Concentration of trace elements in feathers of three Antarctic penguins: Geographical and interspecific differences

Antarctica is often considered as one of the last pristine regions, but it could be affected by pollution at global and local scale. Concentrations of Al, Cr, Mn, Fe, Ni, Cu, Zn, As, Se, Cd and Pb were determinated by ICP-MS in feathers (n = 207 individuals) of gentoo, chinstrap and Adélie penguin collected in 8 locations throughout the Antarctic Peninsula (2006-2007). The highest levels of several elements were found in samples from King George Island (8.08, 20.29 and 1.76 μg g(-1) dw for Cr, Cu and Pb, respectively) and Deception Island (203.13, 3.26 and 164.26 μg g(-1) dw for Al, Mn and Fe, respectively), where probably human activities and large-scale transport of pollutants contribute to increase metal levels. Concentrations of Cr, Mn, Cu, Se or Pb, which are similar to others found in different regions of the world, show that some areas in Antarctica are not utterly pristine.

Accumulation and tissue distribution of heavy metals and essential elements in loggerhead turtles (Caretta caretta) from Spanish Mediterranean coastline of Murcia

Sea turtles are of increasing interest as potential bioindicators of the heavy metal pollution in marine ecosystems. In the present work, concentrations of heavy metals and essential elements (As, Cd, Hg, Pb, Se, Zn) in different organs and tissues (liver, kidney, muscle, bone, blood, central nervous system and skin) of loggerhead sea turtles (Caretta caretta) were determined from stranded animals found along the Spanish Mediterranean coastlines of Murcia. Relatively high average levels of As (skin: 52.13 microg g(-1) dry weight; muscle: 40.95 microg g(-1) dry weight), and especially high individual levels of Zn in muscle tissue (1002.4 microg g(-1) dry weight) were detected. Furthermore, a significant degree of organotrophism of Cd was observed in kidney tissue. The concentrations detected, the distribution among the tissues and the differences observed between juvenile and adult specimens are generally compatible with chronic exposure to the elements studied, whilst levels produced by acute exposure were ruled out.

Pollution and physiological variability in gentoo penguins at two rookeries with different levels of human visitation.

Abstract Human activity and specifically tourism has been increasing in Antarctica over the last few years. Few studies have examined the indirect effects of human visits on Antarctic penguin rookeries. This work aims to study the differences between a highly visited (Hannah Point) and a rarely visited (Devils Point, Byers Peninsula) gentoo penguin rookery on Livingston Island. Our results suggest that potential indirect effects of human impact are observed in gentoo penguins at Hannah Point, a colony heavily visited by tourists. Penguins at Hannah Point showed a higher presence of heavy metals such as Pb and Ni and a higher number of erythrocytic nuclear abnormalities than penguins at Devils Point. Immunological parameters showed different results depending on whether we consider the cellular response - the number of lymphocytes being higher in penguins from Hannah Point - or the humoral response - the level of immunoglobulins being higher in penguins from Devils Point. Measurements of corticosterone levels in feathers and heterophil/lymphocyte (H/L) ratio in blood showed lower levels in the heavily visited rookery than in the rarely visited rookery. Finally, we did not detect Campylobacter jejuni, a bacteria potentially transmitted by humans in either of the populations and we did not find any difference in the prevalence of Campylobacter lari between the populations.

Gastrointestinal parasites in Chinstrap Penguins from Deception Island, South Shetlands, Antarctica

Knowledge about parasites of Antarctic birds is fragmented and scarce. The aim of this work is to contribute to the knowledge of gastrointestinal parasites of the Chinstrap Penguin (Pygoscelis antarctica) from Deception Island (South Shetlands, Antarctica). Gastrointestinal tracts of 64 fresh dead individuals (61 chicks and three adults) were collected from December 2006 to February 2009 and examined for macroparasites. Three adult parasite species were found: two Cestoda species (Parorchites zederi and Tetrabothrius pauliani) and one Nematoda species (Stegophorus macronectes). Also, immature acanthocephalans (Corynosoma sp.) were found in one penguin. The low parasite richness observed could be related to the stenophagic and pelagic diet of the host species. False negatives were found in coprological studies.

Seabird ticks (Ixodes uriae) distribution along the Antarctic Peninsula

The distribution of the tick Ixodes uriae is studied in the South Shetlands and different locations along the Antarctic Peninsula. Ticks were found beneath stones close to penguin rookeries of chinstrap, gentoo and adelie penguin, although no individuals were found parasitized. Our results showed that ticks are not distributed evenly along the Antarctic Peninsula being more common and abundant in the northern part with relative abundances of ticks ranging from 1 to 57 individuals per stone and from 2 to 26% of the stone inspected. Ticks are probably absent in the south.

Age-Related Differences in the Gastrointestinal Microbiota of Chinstrap Penguins (Pygoscelis antarctica)

The gastrointestinal tract microbiota is known to play very important roles in the well being of animals. It is a complex community composed by hundreds of microbial species interacting closely among them and with their host, that is, a microbial ecosystem. The development of high throughput sequencing techniques allows studying the diversity of such communities in a realistic way and considerable work has been carried out in mammals and some birds such as chickens. Wild birds have received less attention and in particular, in the case of penguins, only a few individuals of five species have been examined with molecular techniques. We collected cloacal samples from Chinstrap penguins in the Vapour Col rookery in Deception Island, Antarctica, and carried out pyrosequencing of the V1-V3 region of the 16S rDNA in samples from 53 individuals, 27 adults and 26 chicks. This provided the first description of the Chinstrap penguin gastrointestinal tract microbiota and the most extensive in any penguin species. Firmicutes, Bacteoridetes, Proteobacteria, Fusobacteria, Actinobacteria, and Tenericutes were the main components. There were large differences between chicks and adults. The former had more Firmicutes and the latter more Bacteroidetes and Proteobacteria. In addition, adults had richer and more diverse bacterial communities than chicks. These differences were also observed between parents and their offspring. On the other hand, nests explained differences in bacterial communities only among chicks. We suggest that environmental factors have a higher importance than genetic factors in the microbiota composition of chicks. The results also showed surprisingly large differences in community composition with other Antarctic penguins including the congeneric Adélie and Gentoo penguins.

Distribution of metals and trace elements in adult and juvenile penguins from the Antarctic Peninsula area

The presence of metals in the Antarctic environment is principally a natural phenomenon caused by geochemical characteristics of the region, although some anthropogenic activities can increase these natural levels. Antarctic penguins present several of the characteristics of useful sentinels of pollution in Antarctica such as they are long-lived species situated at the top of food web. The concentrations of Al, Cr, Mn, Fe, Ni, Cu, Zn, As, Se, Cd, and Pb were determined by inductively coupled plasma–mass spectrometry in samples of liver, kidney, muscle, bone, feather, and stomach contents of gentoo, chinstrap, and Adélie penguin (12 adults, five juveniles) from carcasses of naturally dead individuals collected opportunistically in the Antarctic Peninsula area. The obtained results showed that accumulation and magnification of several elements can be occurring, so that Cd and Se reached levels potentially toxic in some specimens. The presence of human activities seems to be increasing the presence of toxic metals such as Mn, Cr, Ni, or Pb in penguins.

Monitoring trace elements in Antarctic penguin chicks from South Shetland Islands, Antarctica

UNLABELLED The concentration of human activities in the near-shore ecosystems from the northern Antarctic Peninsula area can cause an increasing bioavailability of pollutants for the vulnerable Antarctic biota. Penguin chicks can reflect this potential impact in the rookeries during the breeding season. They also can reflect biomagnification phenomena since they are on the top of the Antarctic food chain. The concentrations of Al, Cr, Mn, Fe, Ni, Cu, Zn, As, Se, Cd and Pb were measured by ICP-MS in samples of liver, kidney, muscle, bone, feather and stomach content of gentoo, chinstrap and Adélie penguin chicks (n=15 individuals) collected opportunistically in the Islands of King George and Deception (South Shetland Islands, Antarctica). The detected levels of some trace elements were not as low as it could be expected in the isolated Antarctic region. Penguin chicks can be useful indicators of trace elements abundance in the study areas. CAPSULE Carcasses of Antarctic penguin chicks were used to evaluate the bioavailability of trace elements in the Islands of King George and Deception.

A study of the influence on diabetes of free and conjugated bisphenol A concentrations in urine: Development of a simple microextraction procedure using gas chromatography-mass spectrometry.

The association between bisphenol A (BPA) exposure and adult health status is examined by measuring the urinary BPA concentration using a miniaturized technique based on dispersive liquid-liquid microextraction (DLLME) in combination with gas chromatography-mass spectrometry (GC-MS). Both the free bioactive and the glucuronide conjugated forms of BPA were measured, the glucuronide form usually being predominant. The main analogs of BPA, including bisphenol Z (BPZ), bisphenol F (BPF) and biphenol (BP) were also determined. Several parameters affecting enzymatic hydrolysis, derivatization by in-situ acetylation and the DLLME stages were carefully optimized by means of multivariate designs. DLLME parameters were 2mL urine, 1mL acetone and 100μL chloroform, and hydrolysis was performed using β-glucuronidase and sulfatase at pH 5. No matrix effect was observed and quantification was carried out by aqueous calibration with a surrogate standard. Detection limits were in the range 0.01-0.04ngmL(-1). The intraday and interday precisions were lower than 11% in terms of relative standard deviation. Satisfactory values for all compounds were obtained in recovery studies (92-117%) at two concentration levels. Other bisphenols (BPF, BPZ and BP) were not detected in the urine samples, while BPA was the only bisphenol detected in the free form (creatinine adjusted) at concentration levels ranging from the detection limit to 15.9ngg(-1), and total BPA was detected at concentrations ranging from 0.46 to 24.5ngg(-1) levels. A comparison of the BPA content for both groups of patients revealed that slightly higher mean values were obtained for both free BPA and total BPA for diabetic patients, than for non-diabetic patients. However, a statistical comparison of the contents of BPA revealed that there were no significant differences. The procedure was validated using a certified reference material.

Morphological, molecular and phylogenetic analyses of the spirurid nematode Stegophorus macronectes (Johnston & Mawson, 1942).

Stegophorus macronectes (Johnston & Mawson, 1942) is a gastrointestinal parasite found in Antarctic seabirds. The original description of the species, which was based only on females, is poor and fragmented with some unclear diagnostic characters. This study provides new morphometric and molecular data on this previously poorly described parasite. Nuclear rDNA sequences (18S, 5.8S, 28S and internal transcribed spacer (ITS) regions) were isolated from S. macronectes specimens collected from the chinstrap penguin Pygoscelis antarctica Forster on Deception Island, Antarctica. Using 18S rDNA sequences, phylogenetic analyses (maximum likelihood, maximum parsimony and Bayesian inference) of the order Spirurida were performed to determine the phylogenetic location of this species. Primer pairs of the ITS regions were designed for genus-level identification of specimens, regardless of their cycle, as an alternative to coprological methods. The utility of this molecular method for identification of morphologically altered specimens is also discussed.