Arnthor Gardarsson 1938–2022

Abstract

Professor Arnthor Gardarsson (1938–2022) was an Icelandic ornithologist who made a major contribution to the studies of the bird fauna of Iceland and to the ecology of waterfowl and wetland conservation. After finishing a BSc in Zoology from the University of Bristol in 1962 he went to the University of California, Berkeley, for a PhD project under the supervision of Professor Frank A. Pitelka. His project, finished in 1971, was about the population and feeding ecology of the Icelandic Ptarmigan Lagopus muta islandorum. In 1971–73, working with the Icelandic Museum of Natural History, he conducted a research programme on the ecology of the Thjorsarver area. This tundra oasis in the otherwise desert-like Icelandic highlands harboured the world's largest breeding colony of the Pink-footed Goose Anser brachyrhynchus and was under serious threat by hydropower development. A part of this ecosystem-oriented study involved aerial surveys of birds, a method that was to become one of Arnthor's signature research tools. Waterfowl held a special place in Arnthor's heart. The opportunity to study them in detail came in 1974 when Lake Myvatn, the world-renowned waterfowl site in Iceland, was defined as a nature reserve. This was in the wake of a heated debate over a hydropower project that would have fundamentally altered the lake's ecology. In 1974, Arnthor became professor in zoology at the new biology department of the University of Iceland and he promptly focused his academic research effort on Lake Myvatn. The idea was to monitor the ecological situation of the lake by studying its many duck populations. Despite the newly acquired protection status, there was concern about ongoing industrial sediment extraction from the lake (continuing till 2004). Arnthor's efforts, with students and collaborators, soon developed into a full-scale ecological study of the lake's foodweb, benefiting from his deep insight into ecological processes. His research revealed immense fluctuations in the Lake Myvatn ecosystem, that still occur and continue to attract scientific interest. The studies resulted in a series of classic papers, demonstrating how the variable abundance of aquatic insects and crustaceans in a lake determined duckling production and subsequent changes in breeding populations. It was Arnthor's ambition to obtain a comprehensive picture of the bird populations of Iceland, their distribution, size, production, resources, and trends. It was a gargantuan task, considering the size, remoteness and ruggedness of the landscape and the sheer number of birds. But Arnthor was a daredevil who was quick to apply aerial surveys to the mapping and photographing of all the important bird areas, both coastal and inland, and he kept seeking new techniques to this effect. Estimating bird densities in the immense, towering seabird colonies of northwest Iceland was his biggest challenge. His final solution was to fly low over and then off the cliff edge, taking a rapid succession of photographs with a large-format camera aimed slightly backwards – a rather risky undertaking with the myriad of fast-flying birds around. His aerial endeavours, backed up by field studies, resulted in comprehensive population estimates of alcids, Black-legged Kittiwakes Rissa tridactyla, Northern Fulmars Fulmarus glacialis, Northern Gannets Morus bassanus, European Shags Gulosus aristotelis, Great Cormorants Phalacrocorax carbo, Common Eiders Somateria mollissima and other ducks, swans, geese and even passing migratory waders such as Red Knots Calidris canutus, Ruddy Turnstones Arenaria interpres and Sanderlings Calidris alba. Later he extended the surveying to cover all the Atlantic Puffin Fratercula arctica colonies of Iceland and developed methods to monitor seabird trends via ground-based observations. Arnthor also used his skills to reveal the details of the population dynamics of European Shags and Great Cormorants in the Breidafjördur archipelago, their central stronghold in Iceland. Spring field trips with his students to the impressive seabird colonies in the northwest of Iceland made an enduring impact on many, who are now continuing and expanding the monitoring work on birds in marine, freshwater and terrestrial habitats all over Iceland. Arnthor served as a chairman of the Nature Conservation Council in 1990–96, a government advisory body that also managed protected areas. Through this he became a leading figure in the protection of many of the ecosystems he had studied, in particular Thjorsarver and Myvatn, the crown jewels of inland wetland sites in Iceland. In addition to his extensive ornithological skills, Arnthor had a fascination for terrestrial and marine invertebrates, polychaetes in particular, and he was proficient in botany. He was also artistic and made a name for himself at a young age when illustrating papers on bird life. Arnthor's character may be described as an attractive mix of generousity, ambition and shyness, as well as being humble, friendly and joyful. In 1959 Arnthor married Gudrun Sveinbjarnardóttir (1937–2016), an economist from Reykjavik. They had two children, Soffia and Thrandur.