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Endemic Westland petrels ( Procellaria westlandica ) are a remnant of extensive seabird populations that occupied the forested hill country of prehuman New Zealand. Because seabird guano is rich in Se, an often-deficient essential element, we proposed that Westland petrels enhance Se concentrations in ecosystems associated with their breeding grounds. We sampled terrestrial (soil, plants, riparian spiders) and freshwater (benthic invertebrates, fish) components from Westland petrel-enriched and non-seabird forests on the western coast of New Zealand's South Island, an area characterised by highly leached, nutrient-poor soils. Median seabird soil Se was an order of magnitude higher than soil from non-seabird sites (2.2 mg kg − 1 compared to 0.2 mg kg − 1 ), but corresponding plant foliage concentrations (0.06 mg kg − 1 ; 0.05 mg kg − 1 ) showed no difference between seabird and non-seabird sites. In streams, Se ranged from 0.05 mg kg − 1 (riparian foliage) to 3.1 mg kg − 1 (riparian spiders and freshwater mussels). However, there was no difference between seabird and non-seabird streams. Stoichiometric ratios (N:Se, P:Se) showed Se loss across all ecosystem components relative to seabird guano, except in seabird colony soil where N was lost preferentially. Seabirds therefore did not enrich the terrestrial plants and associated stream ecosystems in Se. We conclude that incorporation of trace elements brought ashore by seabirds cannot be assumed, even though seabirds are a significant source of marine-derived nutrients and trace elements to coastal ecosystems world-wide. [ABSTRACT FROM AUTHOR]

Ornithogenic sediments are rich in toxic As (arsenic) compounds, posing a potential threat to local ecosystems. Here we analyzed the distribution of As speciation in three ornithogenic sediment profiles (MB6, BI and CC) collected from the Ross Sea region, East Antarctica. The distributions of total As and total P (phosphorus) concentrations were highly consistent in all three profiles, indicating that guano input is a major factor controlling total As distribution in the ornithogenic sediments. The As found in MB6 and CC is principally As(V) (arsenate), in BI As(III) (arsenite) predominates, but the As in fresh guano is largely composed of DMA (dimethylarsinate). The significant difference of As species between fresh guano and ornithogenic sediment samples may be related to diagenetic processes after deposition by seabirds. Based on analysis of the sedimentary environment in the studied sediments, we found that the redox conditions have an obvious influence on the As speciation distribution. Moreover, the distributions of As(III) and chlorophyll a in the MB6 and BI profiles are highly consistent, demonstrating that aquatic algae abundance may also influence the distribution patterns of As speciation in the ornithogenic sediments. [ABSTRACT FROM AUTHOR]

Differential distribution of nutrients within an ecosystem can offer insight of ecological and physical processes that are otherwise unclear. This study was conducted to determine if enrichment of phosphorus (P) in tree island soils of the Florida Everglades can be explained by bird guano deposition. Concentrations of total carbon, nitrogen (N), and P, and N stable isotope ratio (δ 15 N) were determined on soil samples from 46 tree islands. Total elemental concentrations and δ 15 N were determined on wading bird guano. Sequential chemical extraction of P pools was also performed on guano. Guano contained between 53.1 and 123.7 g-N kg − 1 and 20.7 and 56.7 g-P kg − 1 . Most of the P present in guano was extractable by HCl, which ranged from 82 to 97% of the total P. Total P of tree islands classified as having low or high P soils averaged 0.71 and 40.6 g kg − 1 , respectively. Tree island soil with high total P concentration was found to have a similar δ 15 N signature and total P concentration as bird guano. Phosphorus concentrations and δ 15 N were positively correlated in tree island soils (r = 0.83, p < 0.0001). Potential input of guano with elevated concentrations of N and P, and 15 N enriched N, relative to other sources suggests that guano deposition in tree island soils is a mechanism contributing to this pattern. [ABSTRACT FROM AUTHOR]

Lake Ellasjøen and Lake Øyangen are two high Arctic lake ecosystem located on the island Bjørnøya (74°30′ N, 19°00′ E) in the Barents Sea. High levels of persistent organic pollutants (POPs), especially PCB and p,p′-DDE, were found in sediment and biota from Lake Ellasjøen while levels were several times lower in Lake Øyangen. Stable isotope signatures (δ15N) in comparable organisms (e.g. zooplankton, Arctic char) collected from both the lakes were also significantly different. The values of δ15N were 6–10‰ higher in the organisms from Ellasjøen than from Øyangen. In both Ellasjøen and Øyangen, a statistically significant correlation (P<0.05) was found between the levels of PCB and DDT, and δ15N values in organisms indicating enhanced bioaccumulation for higher trophical level lake organisms. As the lakes on Bjørnøya are remote, more than 500 km from any known point source, the presence of POPs is most likely the result of long-range transport of contaminants to the area. The observed higher contaminant concentrations associated with the Ellasjøen ecosystem is attributed to two factors. Ellasjøen is located in the southern, mountainous part of Bjørnøya and it is likely that this area receives more precipitation, and thereby more airborne contaminants, than the flatter areas further north on the island (i.e. the area around Øyangen). In addition, higher δ15N-levels in organisms from Ellasjøen as compared to Øyangen indicate the input of guano from seabirds using the lake as a resting area as an additional source of POPs to Ellasjøen. [Copyright &y& Elsevier]

The presence and persistence of microplastics in the environment is increasingly recognized, however, how they are distributed throughout environmental systems requires further understanding. Seabirds have been identified as vectors of chemical contaminants from marine to terrestrial environments, and studies have recently identified seabirds as possible vectors of plastic pollution in the marine environment. However, their role in the distribution of microplastic pollution in the Arctic has yet to be explored. We examined two species of seabirds known to ingest plastics: northern fulmars (Fulmarus glacialis ; n = 27) and thick-billed murres (Uria lomvia ; n = 30) as potential vectors for the transport of microplastics in and around breeding colonies. Our results indicated anthropogenic particles in the faecal precursors of both species. Twenty-four anthropogenic particles were found in the fulmar faecal precursor samples (M = 0.89, SD = 1.09; 23 fibres and one fragment), and 10 anthropogenic particles were found in the murre faecal precursor samples (M = 0.33, SD = 0.92; 5 fibres, 4 fragments, and one foam). Through the use of bird population surveys and the quantification of anthropogenic particles found in the faecal precursors of sampled seabirds from the same colony, we estimate that fulmars and murres may deposit between 3.3 (CI boot 1.9 × 106–4.9 × 106) and 45.5 (CI boot 9.1 × 106–91.9 × 106) million anthropogenic particles, respectively, per year into the environment during their breeding period at these colonies. These estimates indicate that migratory seabirds could be contributing to the distribution and local hotspots of microplastics in Arctic environments, however, they are still likely a relatively small source of plastic pollution in terms of mass in the environment and may not contribute as much as other reported sources such as atmospheric deposition in the Arctic. Unlabelled Image • Arctic colonial seabirds were examined to assess microplastic deposition via guano. • Microplastics were found in the faecal precursors of two species of seabirds. • Colonial seabirds could be an important source of microplastics in the Arctic. [ABSTRACT FROM AUTHOR]

Seabirds, with approximately 1 billion specimens, are the main exchangers of nutrients between Terrestial and Marine Systems and they have become an emerging interest group because of their effects on the planet's ecosystem. This review paper aims to highlight the impact of seabird droppings at different trophic levels, their occurrence, ecological risks and effects on soil, water, atmosphere and biota at global and local level to try to understand the ecological and climatic changes associated with the activities of these birds. Seabirds they have a very marked influence on the ecosystems where they form their colonies since, in addition to their function as predators, alongside with their depositions, they condition the primary producers and, consequently, the rest of the food chain. Their excrements contain large amounts of N, P and trace elements, most of which are bioavailable. In this study, besides bringing together the different works on nutrients and trace elements in excrements and differentiating some terms referring to these excrements, a brief historical overview of their importance for agriculture is made. In addition, the impacts produced by these birds on the ecosystem are also analysed according to two levels, at a global and local level. At each of these levels, a current state of the effects on the different compartments of the ecosystems is made, from the biota to the soils, the water or the atmosphere. This review supports the idea that more studies are needed both at the atmospheric level and in the terrestrial or marine environment for a better understanding of the changes these birds generate. Unlabelled Image • This review discusses the effects of seabird droppings on a local and global scale. • Seabird droppings disrupt the world' s biogeochemical cycles and ecosystems. • Seabirds affect all steps of the food chain, both on land and at sea. • Seabirds can promote the emergence or disappearance of species and ecosystems. • Reference values are presented for different elements produced or contained in seabirds. [ABSTRACT FROM AUTHOR]

• δ15N of TN and inorganic N (NH 4 + and NO 3 −) in soil, moss and aquatic microbial mat were investigated. • δ15N values of soil far outside the penguin colonies resembled those in penguin colonies. • The moss impacted by guano was more enriched in δ15N than in guano-free areas. • Aquatic microbial mat near penguin colonies was 15N-enriched, while 15N-depleted at upland sites. Penguin colonies in Antarctica offer an ideal "natural laboratory" to investigate ecosystem function and the nitrogen (N) cycle. This study assessed the spatial distribution of penguin-derived N from guano and quantitatively assessed its impact on plant N utilization strategies in Victoria Land, Ross Sea region, Antarctica. Soil, moss, and aquatic microbial mats were collected inside and outside an active Adélie penguin (Pygoscelis adeliae) colony and analyzed for δ15N of total and inorganic nitrogen (NH 4 +-N and NO 3 −-N). The soil total nitrogen (TN), NH 4 +-N, and NO 3 −-N concentrations, as well as their δ15N values were significantly higher in guano-impacted areas than those in guano-free areas, verifying that guano is an important N source at and near penguin colonies. However, even far from the penguin colonies, soil δ15N values resembled those in penguin colonies, suggesting strong spatial impacts of penguin-derived N. The moss impacted by guano was more enriched in δ15N than in guano-free areas. The δ15N values of NH 4 +-N and NO 3 −-N in soils covered with moss revealed that the moss might prefer inorganic N in the absence of guano, while the dissolved organic N would become an important source for moss growing on ornithogenic soils. Aquatic microbial mat samples near penguin colonies were 15N-enriched, but 15N-depleted at upland sites. [ABSTRACT FROM AUTHOR]