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RESPONDENT
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Benoit Sittler
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SITE NAME
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Traill Island, Karupelv Valley, Greenland, Denmark
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| Contact details
(phone/fax//e-mail//address): |
| (49-761)2033629/(49-761)2033638 // sittler@ruf.uni-freiburg.de // Institut fur Landespflege Albert-Ludwigs-Universitat Freiburg D-79085 Freiburg, Germany
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PROJECT DETAILS |
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Project name:
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Long term study on lemmings in Karupelv Valley
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Start of survey:
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End
of survey: |
Team
size: |
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WEATHER
CONDITIONS
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Weather conditions: |
| Observations on snow melt chronology in June indicated that it occurred a few days earlier than in 2006, and this was in line with the trend becoming apparent from our long-term observations.
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| Date of ice-break on
rivers: |
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| Date of final loss of
snow: |
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BIOTIC
CONDITIONS
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| Rodents abundance evaluation: |
low
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Breeding conditions:
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Compared to 2006, the figure of 214 lemming winter nests recorded was less than one third compared to that registered in 2006. This was regarded as typical for classical lemming lows, and this figure matched well with the output of the trapping session started in the end of June. The density, evaluated as being of the order of 1 to 2 lemming /10 hectare, was well reflected in the response of the predators. The most striking was the complete absence of Snowy Owls. Long-tailed Skuas were present according to their usual migration pattern, but birds observed in the restricted study area apparently gave up territorial behaviour soon after their arrival, as large flocks (nearly hundred birds) were seen during the earliest surveys. The rarity of lemmings as their main prey is further reflected in the fact that of 8 Arctic Fox dens checked, only one showed evidence of reproduction, but a single pup observed early in the season was not recorded later. The extreme rarity of direct observations of foxes also deserves mentioning, and could be related to increased mortality in the previous winter.
The pattern exhibited by Ermines is of special interest in two major respects. The 34 lemming nest taken over and used are the highest absolute figure ever recorded during this long-term monitoring and also the relative proportion of one Ermine nest/per 6 lemming nest is the highest ratio recorded. Therefore, the situation experienced by lemmings in their subnivean retreat could have hardly produced any other density.
Breeding proved among Rock Ptarmigans (at least 4 cases) also deserve a special mention when compared to previous years. Waders were breeding more or less in average numbers but non-systematic observations late in the season suggest poor breeding success.
Observations made by another team in adjacent areas in August (around Kong Oscars Fjord) suggest that these areas shared similar lemming and predator patterns to those recorded on Traill Island.
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Rodent dynamics:
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Rodent species recorded:
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Summary
of fauna studies: |
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