Insects in Svalbard: What is there and what do we know?
Top image: The collembola Ceratophysella. Photo: Steve Coulson.
There are over 500 species of insect, mite and other creepy crawly recorded from Svalbard. They play a vital role in the ecosystem, and it is therefore important to understand the biodiversity present in Svalbard so as to better understand ecosystem function and provide a baseline for future environmental change studies.
18 June 2012
Text: Steve Coulson, UNIS Associate Professor in Terrestrial Ecology
Despite appearances, there are over 500 species of insect, mite and other creepy crawly recorded from Svalbard. These can occur in vast numbers, for example Collembola (springtails) densities regularly exceeding 500,000 per quadrat metre.
But apart from their inherent interest and often great beauty, they play a vital role in the ecosystem, cycling nutrients and involved in the formation of organic soils. It is therefore important to understand the biodiversity present in Svalbard so as to, for example, better understand ecosystem function and provide a baseline for future environmental change studies.
Probably the most complete inventory of this fauna for any Arctic region is that for the Svalbard archipelago. However, this list is drawn from publications spanning the last 150 years and there is much uncertainty as taxonomists have been constantly revising the various groups of animals.
Classical taxonomy works by separating species on the basis of differences in morphology, for example, the position of location pores and setae (hairs) on the body surface. To successfully identify a species it is often necessary to be an expert in that particularly group since great skill is needed to evaluate the characters correctly.
Opinions as to what comprise good characters by which to distinguish two related species change as our knowledge of the groups improve. For example, a species previously considered to be only one species may be divided into two species on the basis of developments in taxonomy, improved microscopes and so on. Similarly, two species once considered to be separate may be revised into one morphologically diverse species. This has resulted in some species being referred in the inventories of Svalbard by various names.
Mistaken identity common
Some species have only been recorded from Svalbard once. These may well be mistakenly identified. In an ideal world identified material is deposited in museums available for inspection by the next generation of taxonomists. In the real world, such collections may never by assembled or they become lost. Personalities come into play as well.
As is the case of the collection of Sig Thor. Thor was a Norwegian mite taxonomist who identified and named several new species from Svalbard during the 1930’s. Some have not been found since. Are these true species or was Thor mistaken? It is hard to know since after his death his entire collection was destroyed in accordance with his will. He did not wish his treasured collection falling into the hands of his Swedish competitor who had criticised his descriptions and who had the temerity to suggest that specimens in Thor’s collection should be re-examined. Other species not often seen are beginning to occur more regularly, often for unclear reasons such the sea bird tick, while new species are constantly being recorded, such as the mite Thinoseius spinosus.
So, many questions concerning the invertebrate inventory of Svalbard arise. For example, how many species are there really? How do we know what is actually present in Svalbard? How do we study the functioning of the ecology of the archipelago without a good knowledge of the community and, not least, how do we construct a baseline by which to observe the effects of climate change on the community?
Work at UNIS is focussed at resolving as many of these conundrums as possible. One approach is that of DNA-barcoding. This and other molecular techniques may reveal the occurrence of cryptic species, that is groups of animals morphologically identical and considered one species but with distinct genetic lineages. Others use traditional taxonomy studying how the animal looks, for example the presence and position of hairs (setae) of pores on the body surface. One project is aimed at resolving some of these issues by examining fresh material collected during numerous field campaigns and often with collaboration from non-biologists. These samples are then sorted and identified by qualified taxonomists using up-to-date techniques and, critically, the animals are deposited in museum collections – here at UNIS and at the institution of the taxonomist involved. These samples are logged and available for future examination when new taxonomy issues arise.
Through initiatives such as these, our view of the complexity and diversity of the invertebrate community in Svalbard is gradually becoming clearer, improving our understanding of ecosystem function in this archipelago and hence the Arctic in general.
S.P.I.D.E.R. – Svalbardinsects.net