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RESPONDENT
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Gilles Gauthier
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SITE NAME
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Bylot Island, Nunavut, Canada
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| Contact details
(phone/fax//e-mail//address): |
| // Gilles.Gauthier@bio.ulaval.ca // Departement de biologie & Centre d'etudes nordiques, Universite de Laval, St. Foy, Quebec City, Quebec, G1K 7P4 Canada
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PROJECT DETAILS |
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Project name:
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POPULATION STUDY OF GREATER SNOW GEESE ON BYLOT ISLAND (NUNAVUT) IN 2003
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Start of survey:
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End
of survey: |
Team
size: |
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30.05
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21.08
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WEATHER
CONDITIONS
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Weather conditions: |
| The spring 2003 was characterized by an early snowmelt due to a very thin snow-pack and mild temperatures. Snow depth on 2 June was 7 cm compared to a long-term average of 32 cm. Temperature in spring was also relatively mild with an average air temperature of 0.45øC between 20 May and 20 June compared to a long-term average of -0.08øC. Consequently, the rate of snowmelt was rapid and comparable to the earliest years such as 1997 and 1998. Precipitation was extremely low for the first half of the summer (only 8 mm from 1 June to mid-July) with very long spells of sunshine and warm temperature. This weather, in combination with the limited spring run off, lead to almost drought conditions in early July. However, there was a dramatic turnaround in weather conditions as the rest of the summer was cool with little sunshine and very high precipitations (35 mm of rain from mid- to late July and 49 mm from 1 to 20 August), including a precipitation record for a single day (24 mm on 4 August). This resulted in extensive flooding of lowlands in August, especially polygon tundra which was covered by several cm of water for several days. Finally, the ground was partially or totally covered by snow from 13 August until camp closure due to frequent snow showers.
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| Season temperature: |
average
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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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Breeding activity of Arctic Foxes was low. Given the absence of lemmings this year, not a single nest of Snowy Owls was found despite extensive searches.
Arrival of geese on Bylot Island was relatively early in 2003 compared to previous years, which is in accordance with the favourable weather conditions prevailing in spring on Bylot Island. Median egg-laying date was 9 June, which is a few days earlier than normal. Reproductive effort of geese was very high at the main breeding colony. Average clutch size was 3.90, which is above the long-term average. As with nest initiation date, it is the first year that clutch size is higher than the long-term average since the instauration of the spring hunt in 1999. Nesting success (proportion of nests hatching at least one egg) was very good this year (82%), and among the highest values ever reported. Activity of predators at goose nests, especially Arctic foxes, was low even if the lemming population (the main prey of predators) was still very low on Bylot Island following the peak of 2000. Peak hatch was on 6 July, also earlier than normal. The gosling:adult ratio among geese captured at banding (1.31:1) and mean brood size (2.74 young, SD = 1.14, n = 54) were both above the long-term average. By combining information on brood size and young:adult ratio at banding, we estimated that 96% of the adults captured were accompanied by young. All these values are indicative of a very good production of young on Bylot Island this year. Indeed, the value of 27% young in the fall flock in Quebec was slightly above average (24%).
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Rodent dynamics:
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| For our small-mammal survey, we accumulated 1648 trap-nights in three trapping sites, but no lemmings were captured. Therefore, they were still in the low phase of their cycle on the island following the peak of 2000 at the Base-camp Valley and 2001 at Camp-2. Based on the 3 to 4-year cycle of abundance that prevail on Bylot Island since 1993, we expect a peak in lemming abundance in 2004.
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Rodent species recorded:
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Summary
of fauna studies: |
| The study of reproductive ecology of Greater Snow Geese continued at the Bylot Island breeding colony in 2003.
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