Seabird guano boosts body size of water bears (Tardigrada) inhabiting the arctic tundra
(1) During the Arctic summer, little auks (Alle alle) deposit considerable amounts of guano on land. Ecosystems subsidised in nutrients are known to hold greater biodiversity and to produce grander biomass of plants and animals compared with areas where seabirds do not nest. (2) The aim of this study was to look into the relationship between guano fertilisation and body size of invertebrates inhabiting tundra. (3) The specimens of Macrobiotus islandicus islandicus Richters, 1904, a tardigrade dwelling in mosses and lichens of the Arctic, from six different populations from Spitsbergen (Hornsund fjord) were measured. Tardigrades were collected from areas different in terms of seabird guano effects on the tundra ecosystem. An overall body size index for tardigrades was calculated using a principal component analysis. (4) Here, we show that the body size of M. i. islandicus is larger in vicinities of the little auk colonies than in areas devoid of bird nesting sites. (5) Given that fitness of many invertebrates is positively correlated with their condition, our study underlines the ecological importance of a side effect of seabirds biology—the transfer of nutrients from the sea to the land.
KeywordsAlle alle Ecosystem subsidy Macrobiotus islandicus islandicus Svalbard
Sampling was conducted within the project “Research in Svalbard” (RIS No. 5326) and supported financially by a National Science Centre grant no. NN305376438 to JS, NN304014939 to ŁK, JS, ŁM and KZ and by the Polish Ministry of Science and Higher Education via the “Diamond Grant” programme (Grant No. DI2011 035241) to KZ.
- Coulson SJ, Convey P, Aakra K, Aarvik L, Ávila-Jiménez ML, Babenko A, Biersma EM, Boström S, Brittain JE, Carlsson AM, Christoffersen K, De Smet WH, Ekremj T, Fjellberg A, Füreder L, Gustafssonm D, Gwiazdowicz DJ, Hansen LO, Holmstrup M, Hullé M, Kaczmarek Ł, Kolicka M, Kuklin V, Lakka HK, Lebedeva N, Makarova O, Maraldo K, Melekhina E, Ødegaard F, Pilskog HE, Simon JC, Sohlenius B, Solhøy T, Søli G, Stur E, Tanasevitch A, Taskaeva A, Velle G, Zawierucha K, Zmudczyńska-Skarbek K (2014) The terrestrial and freshwater invertebrate biodiversity of the archipelagoes of the Barents Sea; Svalbard, Franz Josef Land and Novaya Zemlya. Soil Biol Biochem 68:440–470Google Scholar
- Dastych H (1985) West Spitsbergen Tardigrada. Acta Zool Crac 28:169–214Google Scholar
- Dubiel E, Olech M (1992) Ornithocoprophilous plant communities of the southern slope of Ariekammen (Hornsund region, Spitsbergen) Landscape, Life World and Man in High Arctic. Institute of Ecology PAS, Warszawa. pp 167–175Google Scholar
- Isaksen K, Gavrilo MV (2000) Little Auk Alle alle. In: Anker-Nilssen T, Bakken V, Strøm H, GolovkinAN, Bianki VV, Tatarinkova I P (eds) The status of marine birds breeding in the barents sea region. Norsk Polarinstitutt Rapportserie Nr. 113, Norwegian Polar Institute, TromsøGoogle Scholar
- Jakubas D, Zmudczyńska K, Wojczulanis-Jakubas K, Stempniewicz L (2008) Faeces deposition and numbers of vertebrate herbivores in the vicinity of planktivorous and piscivorous seabird colonies in Hornsund, Spitsbergen. Pol Polar Res 2:45–58Google Scholar
- Myrcha A, Tatur A (1991) Ecological role of the current and abandoned penguin rookeries in the land environment of the maritime Antarctic. Pol Polar Res 12:3–24Google Scholar
- Porazinska DL, Wall DH, Wirginia RA (2002) Invertebrates in ornithogenic soils on Ross Island, Antarctica. Polar Biol 25:569–574Google Scholar
- Ramazzotti G, Maucci W (1983) II Phylum Tardigrada (III. edizione riveduta e aggiornata). Mem Ist Ital Idrobiol 41:1–1016Google Scholar
- Stempniewicz L (2005) Keystone species and ecosystem functioning. Seabirds in polar ecosystems. Ecol Quest 6:129–134Google Scholar