Pollutants in Antarctic ecosystems are largely attributed to long range atmospheric transport. However, previous studies confirmed seabird colonies as relevant secondary sources of organic and ...inorganic pollutants. When comparing these data, higher trophic level seabird colonies, small and sparse, did not influence results as strongly as lower trophic level birds large dense colonies. Thus, we cross examined results of stable isotopes and pollutants from lichens, moss and soil samples from Antarctic seabird colonies with their data for population parameters to understand how these variables influence each other. Results showed colonies clearly supplying As, Cd, Hg, Se, Zn, HCB and PCBs and corroborated other local sources. Penguin colonies were the most important pollutants sources hereby studied due to their sheer size and also their recent relative growth. Finally, results suggest climate change should likely increase the concentration of contaminants and the overall burden trapped in Antarctic terrestrial ecosystems.
•Seabird colonies function as relevant secondary pollutants source at a local level.•Results of vegetation and soil around colonies were compared with populational data.•Population size and dynamics were more important than trophic level.•Results suggest climate change to increase pollutant burden in terrestrial Antarctica.
Seabirds are amongst the most affected organisms by plastic pollution worldwide. Ingestion of marine debris has been reported in at least 122 species, and owing to the increasing global production ...and persistence of these anthropogenic materials within the marine environment, it is expected to be a growing problem to the marine fauna. Here we report evidence of an increasing frequency in marine debris ingestion and a decrease in the amount of plastic pellets ingested by White-chinned Petrels attending south Brazilian waters during the last three decades. Future studies comprising large temporal scales and large sample sizes are needed to better understand the trends of marine debris ingestion by seabirds. We expect our findings to highlight the need for prevention policies and mitigation measures to reduce the amount of solid litter in the oceans.
•We reported evidence of an increasing frequency of marine debris ingestion by White-chinned Petrels in southern Brazil.•We also found a decrease in the amount of virgin pellets ingested per individual over the past three decades.•The amount of user plastics ingested per individual did not show any temporal trend.
Five of the seven extant sea turtle species in the world forage on the coast of Southern Brazil at least in some stage of their life cycle. The green turtle Chelonia mydas frequently strands on ...beaches of Rio Grande do Sul State. The species is currently classified as vulnerable to extinction in the region, and pollution by marine debris is one of the most conspicuous threats to its conservation. In this study, we quantified and characterized plastic ingestion by juvenile green turtles in waters off the southern Brazilian coast between 2013 and 2016. We analysed the gastrointestinal content of 17 beached carcasses and registered debris ingestion in 15 individuals (88%). On average, each green turtle ingested 38.4 ± 88.5 plastic fragments. White and transparent plastic bags and plastic sheets were predominant. Our results indicate a high interaction between juvenile green turtles and marine debris off the coast of Southern Brazil.
•Sea turtles are one of the most affected organisms by marine debris ingestion.•We analyzed plastic ingestion by juvenile green turtles in southern Brazil.•A prevalence of 88% of debris ingestion was found.•The most ingested items were plastic sheets and hard plastic fragments.•No correlation was found between the size of turtles and the amount of plastic.
Past research during the breeding season in the Antarctic Peninsula region indicates that gentoo penguins (
Pygoscelis papua
) are generalist foragers whereas Adélie (
P. adeliae
) and chinstrap (
P. ...antarcticus
) penguins tend to specialize on Antarctic krill (
Euphausia superba
). However, little is known about the degree of temporal consistency in the diets and foraging habitats of these three species, particularly at the individual level. Such year-round and inter-annual dietary understanding is important to help interpret contrasting trends in their populations. We used carbon and nitrogen stable isotope analysis of blood and feathers to evaluate seasonal shifts in diet and individual foraging consistency within
Pygoscelis
penguin species breeding in the South Shetland Islands as well as among three geographically distinct gentoo penguin populations in the western Antarctic Peninsula and South Shetland Islands. We found that gentoo penguins exhibited a generalist foraging strategy with individual consistency, Adélie penguins exhibited an intermediate generalist foraging strategy with little individual consistency, and chinstrap penguins exhibited a specialized diet with little inter-individual variation. Our results also indicated that all three species have greater variation in foraging habitat use during the post-breeding season compared to the breeding season. Finally, we observed differences in the degree of seasonal shifts in population level diet and consistency in foraging strategies at the individual level across the three gentoo penguin populations examined. This suggests that
Pygoscelis
penguins can differ in diets and foraging habitat use not only at the population level among species, sites, and seasons, but also in the level of variation within populations, and in the degree of seasonal consistency among individuals.
Available information about seabird breeding population trends on Stinker Point (Elephant Island, Maritime Antarctic Peninsula) is outdated by decades. This study reports current numbers of breeding ...species, and evaluates population trends over 28 years. We counted breeding pairs of seabirds along all ice-free areas on Stinker Point during two distinct periods (summers of 1985/86–1991/92 and 2009/10–2013/14). Thirteen species currently breed in the area: four Sphenisciformes, four Procellariiformes, one Suliforme and four Charadriiformes. Chinstrap penguin Pygoscelis antarcticus has the highest number of breeding pairs (4971±590), followed by gentoo penguin Pygoscelis papua (1242±339). Comparisons between the two intervals showed declining trends for almost all breeding populations, although southern giant petrels Macronectes giganteus are experiencing a subtle population growth. Population decreases in locations with low human disturbance, such as Stinker Point, may indicate sensibility to climate and environmental change and need further investigation.
Many seabird species forage at night and potentially interact with nocturnal fishing activities. Jigging fisheries use powerful lights to attract squid, and such high intensity lights can be recorded ...using global location-sensing loggers (geolocators) attached to seabirds. We use this potential source of information as evidence for interaction of southern giant petrels
Macronectes giganteus
with night fisheries during the non-breeding season. We compared the number of light spikes at night between sexes and evaluated whether the intensity of the light on those geolocator records matched periods of water immersion (wet–dry) of geolocators, as a measure of foraging activity. Females had more night light spikes than males, and although the activity on water was higher during nights with light spikes than nights without light spikes for both sexes, females had a higher probability to be resting on the water when peaks of light were higher. Females moved further north than males and used areas of higher squid fishery activities within Patagonian waters. This type of information is useful to record potential interactions with night fisheries and proposes that future studies should relate the accurate distribution of individuals (from GPS loggers) with light information (geolocators data) to highlight this undocumented interaction. Southern giant petrels are recognized as interacting intensively with fisheries off Patagonia waters with consequences for population dynamics (e.g. mortality through bycatch events).
Literature reports that body size can be associated with latitudinal distribution, for instance larger animals inhabit higher latitudes and colder habitats. This rule can be applied for species and ...populations within a species. The potential influence of body size on non-breeding distribution and habitat use at the intra-population level was investigated for southern giant petrels Macronectes giganteus (Gmelin) from Elephant Island, South Shetland Islands. The non-breeding distribution of 23 individuals was tracked, and total body length, culmen length, wing length, wing load and body mass were measured. Positions of core areas were used to estimate the latitudinal distribution of each individual. Smaller individuals were found to be associated more with lower latitudes, where warmer conditions and more coastal and productive waters prevail, whereas large males were associated more with higher latitudes, with colder conditions near sea ice caps, presumably feeding on carrion or preying on penguins. This association reflects a latitudinal gradient, with smaller individuals positioning themselves towards the north, and larger individuals towards the south. In this case, body size, individual distribution and habitat use were found to be associated, highlighting the importance of studying potential effects of individual body size on the ecology of seabirds.
Seabirds play an important role as top consumers in the food web and can be used as biomonitors of exposure to pollutants. Contamination studies involving non-destructive sampling methods are of ...considerable importance, allowing better evaluation of the levels of pollutants and their toxic effects. In the present study, organohalogen contaminants were analyzed in 113 blood samples from Southern Giant Petrel (Macronectes giganteus) adults and chicks collected in the austral summer of 2011/2012 and 2012/2013 from colonies on Elephant and Livingston Islands, South Shetland, Antarctica. Polychlorinated biphenyls (PCBs), hexachlorobenzene (HCB), pentachlorobenzene (PeCB), mirex, dichlorodiphenyltrichloroetane and derivatives (DDTs) and chlordanes were detected in all birds, whereas polybrominated diphenyl ethers (PBDEs) were not detected in any blood samples. No significant differences were found in organochlorine levels between sampling events. Adults exhibited significantly higher levels than chicks, except for PeCB. PCBs, HCB, mirex and DDTs were statistically similar in males and females from Elephant Island. Females on Livingston Island exhibited higher HCB values than males, but no sex differences were found regarding other organochlorines. The similarity in organochlorine levels between sexes in birds with very marked sexual segregation in feeding habits during the breeding season may indicate that significant amounts of contaminants are acquired during migration to lower latitudes, when the diets of males and females are similar. Birds sampled on Livingston Island exhibited significantly lower levels of PCBs, HCB, DDTs, mirex and chlordanes in comparison to those on Elephant Island, which could be the result of distinct foraging patterns between the two colonies. Organochlorine levels were similar between years in birds captured in two consecutive breeding seasons. Blood samples from Southern Giant Petrels adults and chicks proved to be useful for the comparison of intraspecific contamination levels and appear to be adequate for the long-term assessment of organohalogen contaminants in antarctic top predators.
Organochlorine contaminants in blood samples of Southern Giant Petrels reflected intra-specific differences and suggested distinct foraging patterns between colonies.
•Organohalogen contaminants were assessed in blood samples of Southern Giant Petrels.•Mirex, DDTs, PCBs and HCB were the predominant compounds in blood samples.•Levels of most organochlorines were similar between males and females.•Adults exhibited significantly higher levels than chicks.•Geographic differences between colonies were detected in contamination levels.
Population growth of the southern giant petrel Macronectes giganteus from South America has been linked with an increase in fishing activities. It was demonstrated recently that a population from ...Elephant Island, Antarctic Peninsula, largely overlaps its non-breeding distribution with zones of high fishing intensity off South America. This study investigated the assumption that the increase in this population since the 1980s is related to an increase in fisheries off South America. Our results show that the population size is proportional to the increase in demersal and squid fisheries. These fisheries produce a considerable amount of discards, which can be used by non-breeding southern giant petrels as a food source during unfavourable conditions in winter. This may enhance the adult survival rates with potential carry-over effects on population size. Our study shows that we need to further understand the effects of fishery discards/offal on scavenging seabirds of the Southern Ocean, and highlights the importance of understanding the carry-over effects of seabird–fisheries interactions during the non-breeding phase in population dynamics.
Since pristine Atlantic Forest remnants are vanishing, and biological reserves are in short, conservation of biodiversity will largely depend on proper management of the anthropogenic matrix. Here, ...we test (1) the effectiveness of ecologically-managed tree monocultures in maintaining Araucaria Forest biodiversity, (2) how this effectiveness change among taxa, and (3) we discuss management principles that can be used by the forestry industry in order to contribute positively to biodiversity conservation. The study was conducted in the São Francisco de Paula National Forest, southern Brazil, an environmental mosaic composed mostly of patches of Araucaria Forest and ecologically-managed monocultures of Araucaria, Pinus and Eucalyptus. Using standardized sampling methods in these four main habitats, we have recorded the richness and species composition of small mammals, birds, leaf-litter frogs, butterflies, galling insects, spiders, opiliones, flatworms, woody plants, epiphytic angiosperms, epiphytic ferns, lichens, and fruit-body producing fungi. Overall, we recorded 506 species in Araucaria Forest, 181 (36%) of which were exclusive of this habitat while 325 (64%) could be found in at least one monoculture. Distribution patterns of species richness and number of records across taxonomic groups showed that a large biodiversity can be found inside ecologically-managed plantations of Araucaria, Pinus, and Eucalyptus. For all studied taxa, except for epiphytic angiosperms and fruit-body producing fungi, more than half of the Araucaria Forest species could be found living on monocultures. We discuss how the actual management practices of the forest industry can be improved to contribute positively to the conservation of the Atlantic Forest biodiversity.
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