{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,22]],"date-time":"2026-09-22T21:10:35Z","timestamp":1790111435080,"version":"4.0.1"},"reference-count":42,"publisher":"MDPI AG","issue":"17","license":[{"start":{"date-parts":[[2026,8,28]],"date-time":"2026-08-28T00:00:00Z","timestamp":1787875200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Animals"],"abstract":"<jats:p>Cadmium (Cd) concentrations in Atlantic puffin Fratercula arctica droppings were assessed during chick rearing using non-invasive sampling at nine Icelandic colonies. One fresh dropping was collected immediately after directly observed defecation from each of 159 different individuals in June\u2013July 2018, and Cd was quantified by graphite furnace atomic absorption spectrometry on a dry-weight basis. Reported Cd concentrations were strongly right-skewed (median, 155.2 \u00b5g kg\u22121 dry weight; range, 1.1\u20133539.2 \u00b5g kg\u22121) and differed among colonies in the primary unadjusted comparison (Kruskal\u2013Wallis, p &lt; 0.001), with Holm-adjusted Dunn tests identifying 9 of 36 significant colony pairs. In a secondary model including dry sample mass, the colony effect remained strong (Wald \u03c72(8) = 108.75, p &lt; 0.001), and adjusted geometric means spanned 24.2\u2013506.9 \u00b5g kg\u22121 dry weight (20.9-fold). Variance partitioning yielded an ICC of 0.261 (95% confidence interval, 0.104\u20130.519), which is interpreted as a model-dependent estimate given the nine colonies. No association with chick-provisioning prey composition or breeding performance remained detectable after false-discovery-rate correction. The 2018 dataset therefore shows pronounced colony-scale contrasts in reported Cd concentrations in droppings. Mechanistic attribution requires direct prey measurements and multi-year replication.<\/jats:p>","DOI":"10.3390\/ani16172689","type":"journal-article","created":{"date-parts":[[2026,8,28]],"date-time":"2026-08-28T18:33:52Z","timestamp":1787942032000},"page":"2689","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Non-Invasive Sampling Reveals Colony-Scale Spatial Heterogeneity in Cadmium Concentrations in Atlantic Puffin Fratercula arctica Droppings in Iceland"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6899-701X","authenticated-orcid":false,"given":"Jakub","family":"Skorupski","sequence":"first","affiliation":[{"name":"Institute of Marine and Environmental Sciences, University of Szczecin, Mickiewicza 16 St., 70-383 Szczecin, Poland"},{"name":"The Centre for Molecular Biology and Biotechnology, University of Szczecin, W\u0105ska 13 St., 70-415 Szczecin, Poland"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"conceptualization","vocabulary":"credit"},{"role":"investigation","vocabulary":"credit"},{"role":"visualization","vocabulary":"credit"},{"role":"methodology","vocabulary":"credit"},{"role":"resources","vocabulary":"credit"},{"role":"supervision","vocabulary":"credit"},{"role":"project-administration","vocabulary":"credit"},{"role":"data-curation","vocabulary":"credit"},{"role":"software","vocabulary":"credit"},{"role":"validation","vocabulary":"credit"},{"role":"writing-original-draft","vocabulary":"credit"},{"role":"funding-acquisition","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"},{"role":"formal-analysis","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6094-3647","authenticated-orcid":false,"given":"Arkadiusz","family":"N\u0119dzarek","sequence":"additional","affiliation":[{"name":"Faculty of Food Sciences and Fisheries, West Pomeranian University of Technology in Szczecin, Kazimierza Kr\u00f3lewicza 4 St., 71-550 Szczecin, Poland"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"investigation","vocabulary":"credit"},{"role":"methodology","vocabulary":"credit"},{"role":"resources","vocabulary":"credit"},{"role":"software","vocabulary":"credit"},{"role":"validation","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"}]},{"given":"Remigiusz","family":"Panicz","sequence":"additional","affiliation":[{"name":"Faculty of Food Sciences and Fisheries, West Pomeranian University of Technology in Szczecin, Kazimierza Kr\u00f3lewicza 4 St., 71-550 Szczecin, Poland"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"data-curation","vocabulary":"credit"},{"role":"validation","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7220-5484","authenticated-orcid":false,"given":"Piotr","family":"Eljasik","sequence":"additional","affiliation":[{"name":"Faculty of Food Sciences and Fisheries, West Pomeranian University of Technology in Szczecin, Kazimierza Kr\u00f3lewicza 4 St., 71-550 Szczecin, Poland"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"data-curation","vocabulary":"credit"},{"role":"validation","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5918-0868","authenticated-orcid":false,"given":"Natalia","family":"\u015amietana","sequence":"additional","affiliation":[{"name":"Faculty of Food Sciences and Fisheries, West Pomeranian University of Technology in Szczecin, Kazimierza Kr\u00f3lewicza 4 St., 71-550 Szczecin, Poland"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"investigation","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6899-2817","authenticated-orcid":false,"given":"Erpur Sn\u00e6r","family":"Hansen","sequence":"additional","affiliation":[{"name":"South Iceland Nature Research Centre, \u00c6gisgata 2, 900 Vestmannaeyjar, Iceland"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"conceptualization","vocabulary":"credit"},{"role":"data-curation","vocabulary":"credit"},{"role":"formal-analysis","vocabulary":"credit"},{"role":"funding-acquisition","vocabulary":"credit"},{"role":"investigation","vocabulary":"credit"},{"role":"methodology","vocabulary":"credit"},{"role":"software","vocabulary":"credit"},{"role":"project-administration","vocabulary":"credit"},{"role":"resources","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"}]}],"member":"1968","published-online":{"date-parts":[[2026,8,28]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"153","DOI":"10.1023\/A:1025560805788","article-title":"Seabirds as indicators of changes in marine ecosystems: Ecological monitoring on Machias Seal Island","volume":"88","author":"Diamond","year":"2003","journal-title":"Environ. Monit. Assess."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"263","DOI":"10.1007\/s10393-004-0096-4","article-title":"Marine birds as sentinels of environmental pollution","volume":"1","author":"Burger","year":"2004","journal-title":"EcoHealth"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"142","DOI":"10.1080\/24750263.2020.1853264","article-title":"Potential of invasive alien top predator as a biomonitor of nickel deposition\u2014The case of American mink in Iceland","volume":"88","author":"Skorupski","year":"2021","journal-title":"Eur. Zool. J."},{"key":"ref_4","doi-asserted-by":"crossref","unstructured":"Eeva, T., Raivikko, N., Esp\u00edn, S., S\u00e1nchez-Virosta, P., Ruuskanen, S., Sorvari, J., and Rainio, M. (2020). Bird feces as indicators of metal pollution: Pitfalls and solutions. Toxics, 8.","DOI":"10.3390\/toxics8040124"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"201","DOI":"10.1016\/j.taap.2009.04.020","article-title":"Current status of cadmium as an environmental health problem","volume":"238","year":"2009","journal-title":"Toxicol. Appl. Pharmacol."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"37","DOI":"10.1016\/j.scitotenv.2007.08.037","article-title":"Assessment and management of risk to wildlife from cadmium","volume":"389","author":"Burger","year":"2008","journal-title":"Sci. Total Environ."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"153322","DOI":"10.1016\/j.scitotenv.2022.153322","article-title":"Understanding the combined effects of multiple stressors: A new perspective on a longstanding challenge","volume":"821","author":"Pirotta","year":"2022","journal-title":"Sci. Total Environ."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"1772","DOI":"10.1093\/icb\/icaf123","article-title":"A collaborative multiple stressor approach for identifying spatial heterogeneities in wildlife health and conservation priorities","volume":"65","author":"Simonis","year":"2025","journal-title":"Integr. Comp. Biol."},{"key":"ref_9","doi-asserted-by":"crossref","unstructured":"Berglund, \u00c5.M.M., Rainio, M.J., and Eeva, T. (2015). Temporal trends in metal pollution: Using bird excrement as an indicator. PLoS ONE, 10.","DOI":"10.1371\/journal.pone.0117071"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"1198","DOI":"10.1016\/j.envpol.2017.10.031","article-title":"Evaluating blood and excrement as bioindicators for metal accumulation in birds","volume":"233","author":"Berglund","year":"2018","journal-title":"Environ. Pollut."},{"key":"ref_11","doi-asserted-by":"crossref","unstructured":"Burger, J., Hansen, E.S., Ng, K., and Gochfeld, M. (2025). Element levels in feathers of Atlantic puffins (Fratercula arctica) in Iceland: Establishing background levels in an Arctic migratory species. Toxics, 13.","DOI":"10.3390\/toxics13020103"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"27","DOI":"10.1139\/facets-2015-0009","article-title":"Recent changes in the diet and survival of Atlantic puffin chicks in the face of climate change and commercial fishing in midcoast Maine, USA","volume":"1","author":"Kress","year":"2016","journal-title":"FACETS"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"1152","DOI":"10.1111\/1365-2656.13442","article-title":"Local prey shortages drive foraging costs and breeding success in a declining seabird, the Atlantic puffin","volume":"90","author":"Fayet","year":"2021","journal-title":"J. Anim. Ecol."},{"key":"ref_14","doi-asserted-by":"crossref","unstructured":"Kennerley, W.L., Clucas, G.V., and Lyons, D.E. (2024). Multiple methods of diet assessment reveal differences in Atlantic puffin diet between ages, breeding stages, and years. Front. Mar. Sci., 11.","DOI":"10.3389\/fmars.2024.1410805"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"10865","DOI":"10.5194\/acp-17-10865-2017","article-title":"Temporal and spatial variability of Icelandic dust emission and atmospheric transport","volume":"17","author":"Arnalds","year":"2017","journal-title":"Atmos. Chem. Phys."},{"key":"ref_16","unstructured":"Hansen, E.S. (2018). Stofnv\u00f6ktun Lunda 2018: Framvindusk\u00fdrsla Til Umhverfisstofnunar [Puffin Monitoring 2018: Progress Report to the Environment Agency of Iceland], South Iceland Nature Research Centre. Available online: https:\/\/nattsud.is\/wp-content\/uploads\/2021\/12\/Stofnvoktun-lunda-Framvindukyrsla-2018.pdf."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"357","DOI":"10.1038\/s41586-020-2649-2","article-title":"Array programming with NumPy","volume":"585","author":"Harris","year":"2020","journal-title":"Nature"},{"key":"ref_18","unstructured":"van der Walt, S., and Millman, J. (2010). Data structures for statistical computing in Python. Proceedings of the 9th Python in Science Conference, SciPy."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"261","DOI":"10.1038\/s41592-019-0686-2","article-title":"SciPy 1.0: Fundamental algorithms for scientific computing in Python","volume":"17","author":"Virtanen","year":"2020","journal-title":"Nat. Methods"},{"key":"ref_20","unstructured":"van der Walt, S., and Millman, J. (2010). Statsmodels: Econometric and statistical modeling with Python. Proceedings of the 9th Python in Science Conference, SciPy."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"241","DOI":"10.1080\/00401706.1964.10490181","article-title":"Multiple comparisons using rank sums","volume":"6","author":"Dunn","year":"1964","journal-title":"Technometrics"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"17","DOI":"10.1093\/biomet\/37.1-2.17","article-title":"Notes on continuous stochastic phenomena","volume":"37","author":"Moran","year":"1950","journal-title":"Biometrika"},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"199","DOI":"10.1111\/j.1095-8312.1978.tb00013.x","article-title":"Spatial autocorrelation in biology: 1. Methodology","volume":"10","author":"Sokal","year":"1978","journal-title":"Biol. J. Linn. Soc."},{"key":"ref_24","first-page":"65","article-title":"A simple sequentially rejective multiple test procedure","volume":"6","author":"Holm","year":"1979","journal-title":"Scand. J. Stat."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"289","DOI":"10.1111\/j.2517-6161.1995.tb02031.x","article-title":"Controlling the false discovery rate: A practical and powerful approach to multiple testing","volume":"57","author":"Benjamini","year":"1995","journal-title":"J. R. Stat. Soc. Ser. B"},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"90","DOI":"10.1109\/MCSE.2007.55","article-title":"Matplotlib: A 2D graphics environment","volume":"9","author":"Hunter","year":"2007","journal-title":"Comput. Sci. Eng."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"591","DOI":"10.1093\/biomet\/52.3-4.591","article-title":"An analysis of variance test for normality (complete samples)","volume":"52","author":"Shapiro","year":"1965","journal-title":"Biometrika"},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"583","DOI":"10.1080\/01621459.1952.10483441","article-title":"Use of ranks in one-criterion variance analysis","volume":"47","author":"Kruskal","year":"1952","journal-title":"J. Am. Stat. Assoc."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"103","DOI":"10.1111\/j.2041-210X.2010.00012.x","article-title":"Simple means to improve the interpretability of regression coefficients","volume":"1","author":"Schielzeth","year":"2010","journal-title":"Methods Ecol. Evol."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"935","DOI":"10.1111\/j.1469-185X.2010.00141.x","article-title":"Repeatability for Gaussian and non-Gaussian data: A practical guide for biologists","volume":"85","author":"Nakagawa","year":"2010","journal-title":"Biol. Rev."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"72","DOI":"10.2307\/1412159","article-title":"The proof and measurement of association between two things","volume":"15","author":"Spearman","year":"1904","journal-title":"Am. J. Psychol."},{"key":"ref_32","doi-asserted-by":"crossref","unstructured":"Seber, G.A.F., and Lee, A.J. (2003). Linear Regression Analysis, John Wiley & Sons. [2nd ed.].","DOI":"10.1002\/9780471722199"},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"582","DOI":"10.1111\/j.2517-6161.1968.tb00759.x","article-title":"A simplified Monte Carlo significance test procedure","volume":"30","author":"Hope","year":"1968","journal-title":"J. R. Stat. Soc. Ser. B"},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"3753","DOI":"10.1111\/gcb.15665","article-title":"Centennial relationships between ocean temperature and Atlantic puffin production reveal shifting decennial trends","volume":"27","author":"Hansen","year":"2021","journal-title":"Glob. Change Biol."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"1923","DOI":"10.1007\/s00227-015-2735-4","article-title":"Individual specialization in the foraging and feeding strategies of seabirds: A review","volume":"162","author":"Ceia","year":"2015","journal-title":"Mar. Biol."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"188","DOI":"10.1007\/s00227-024-04502-6","article-title":"Evidence of colony- and individual-level variation in habitat usage of Atlantic puffins (Fratercula arctica): Effect of wintering area and sex","volume":"171","author":"Cleasby","year":"2024","journal-title":"Mar. Biol."},{"key":"ref_37","unstructured":"Whitacre, D. (2013). Do Cd, Cu, Ni, Pb, and Zn biomagnify in aquatic ecosystems?. Reviews of Environmental Contamination and Toxicology, Springer."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"20586","DOI":"10.1007\/s11356-024-32268-3","article-title":"Contrasting trophic transfer patterns of cadmium and mercury in the Arctic marine food web of east Hudson Bay, Canada","volume":"31","author":"Rohonczy","year":"2024","journal-title":"Environ. Sci. Pollut. Res."},{"key":"ref_39","first-page":"181","article-title":"Temporal trends of contaminants in cod from Icelandic waters","volume":"476\u2013477","year":"2014","journal-title":"Sci. Total Environ."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"1675","DOI":"10.1093\/icesjms\/fsm152","article-title":"Diet studies of seabirds: A review and recommendations","volume":"64","author":"Barrett","year":"2007","journal-title":"ICES J. Mar. Sci."},{"key":"ref_41","first-page":"85","article-title":"Mercury, lead, cadmium, selenium, and arsenic in liver, kidney, and feathers of gulls: A review","volume":"Volume 247","year":"2018","journal-title":"Reviews of Environmental Contamination and Toxicology"},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"104","DOI":"10.1080\/02772248.2021.1872574","article-title":"Levels of zinc, cadmium, and lead in liver, kidney, and feathers of Atlantic puffins (Fratercula arctica) from Spain","volume":"103","author":"Barrales","year":"2021","journal-title":"Toxicol. Environ. Chem."}],"container-title":["Animals"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2076-2615\/16\/17\/2689\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,8,30]],"date-time":"2026-08-30T04:27:22Z","timestamp":1788064042000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2076-2615\/16\/17\/2689"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,8,28]]},"references-count":42,"journal-issue":{"issue":"17","published-online":{"date-parts":[[2026,9]]}},"alternative-id":["ani16172689"],"URL":"https:\/\/doi.org\/10.3390\/ani16172689","relation":{},"ISSN":["2076-2615"],"issn-type":[{"value":"2076-2615","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,8,28]]}}}