Kolguyev expedition 2008 - report of 2nd period
The weather in July up to the beginning of August (first nights below zero from the 2nd to the 3rd of August) was rather warm and not much windy, as only two strong storms challenged the camp equipment, but so far no serious damages were done to the tents, except of complete destroy of old “mountain-3” tents. Precipitation level was also moderate and water level in creeks and rivers was always low.
The second part of the expedition was started on June 25-th 2008, after arriving of two new participants – Alena Dolgova, and Egor Yacuk. Six participants continued their research until 27 July, when Jury Anisimov and Dmitri Ochinasko returned back from Peschanka delta, so the last days of July and 19 days of August 8 participants worked together. Bugrino village citizen Albert Ardeev and his son Denis visited the camp in a period of 30 June – 14 July and took part in some of the team work during density plots and female catching.
Our main task for summer 2008
- to establish plots for estimating breeding density of WFG and Bean Geese,
- to locate and describe all existing colonies of Barnacles Geese in the central part of Kolguev,
- to catch females on the nests and supply 10 of them with neckbands with radio transmitters,
- to explore the most southern and the most northern boggy plateaus of Kolguev along with locating PTT-supplied geese (Kees and Marco),
- to check the breeding success of all found geese nests,
- to collect data on breeding biology (phenology, breeding density, clutch size, breeding success) of Barnacle geese in Peschanka delta and compare data with those from 2006,
- to catch nonbreeders and breeders during flight feather moulting for neck-banding of them,
- to locate known fox dens and count number of pups,
- to perform behavioral observations during brood-rearing period,
- to perform regular brood counts in different habitats.
- to perform further checks on 32 vegetation plots containing Carex aquatilis -types or Puccinellia phryganodes / Carex subspathacea -types
- to conduct end of the season measurements in order to assess grazing intensity on specially chosen lakes
Trips to Northern area of the island (Northern lapta), Southern area (Southern lapta), Western area and Northern, Southern and Western mountain areas were made to check nest density there. Altogether more than 600 nests of White-fronted Geese, 87 nests of Bean Geese and 81 nests of Barnacle Geese were found and described in the central part of Kolguev. Additional 150 nests of White-fronted Geese were found and described in Peschanka Delta area. 13 control plots for estimating breeding density were established in the central part, 2 in the north coast and 5 more plots – in Delta area. Estimated breeding density varied from 30 to 80 nests per sq. km and also corresponded well with the percent of snow-free and dry area within the plots during nest initiation. The least density was observed in the boggy parts of southern boggy plateau, and also in Hilly areas of central “Mountains”. The highest density was recorded at the central and northern boggy plateaus.
Late breeding season
Timing of breeding in 2008 was much more delayed in compare with 2006 and 2007, but markedly more synchronous, so the majority of the nests hatched during the period 10 – 20 July. Hatching started on June 26 and finished on July 25 according to our calculations. The mean hatching date is July 13. Clutch size varied from1 to 15 eggs (recorded on one of Peregrine colonies, and in only 5 eggs hatched in that nest. The mean clutch size was 3,54 +/- 0,07 eggs.
Transmittering breeding geese
Intensive catching affair was done during these days in order to mark incubating females during goslings hatching. 12 females were altogether caught and neck banded out of 16 catching trials. 10 of them were supplied with radio transmitters, but it lately appeared that radio signal in depressions where the birds were usually situated, was so weak, that it was practically not possible to follow transmitted bird during their travels. Altogether 18 records were registered for 8 transmitter females, but mainly during first week after marking, when their travels were in the nearest vicinity to the nesting area. Some further registrations could be done in a distance of 2 - 4 km SSE of the camp during the process of accumulating geese flocks at the lake shores and in the vicinity of clustered lakes. As it was obvious after observations of colour-banded geese with known nesting sites, they could lead broods to a distance of 6-7 kilometers during first 3 days after hatching (B73-lime example).
Re-observing marked geese
16 different previously marked Whitefronted geese with neckbands were seen in 2008, and in 14 cases the neckband code was successfully read. MARCO’s nest was also found in the southern part of Kolguev and lately checked for the nesting success during special long 5 days trips. KEES was not seen and might be possibly considered as non- or failed breeder in 2008.
Breeding success 2008
Nest checks for the nesting success was performed for all control plots and for the majority of the other nests in the area, and the average nesting success in 2008 was estimated to be 83%, which might be considered as high, but comparable with the same data for 2007. Similar figures (80% of nesting success) were received for Bean geese.
Much lower breeding success was observed in 2008 in Barnacle geese – 57% at average, with variations from 0% in some “abandoned” Peregrine colonies (Peregrine nests were unsuccessfull) to 90% in “Good colonies”. Several “No-raptor” colonies were also described along the bluffs of Peschanka river.
Continuing banding of geese
After finishing checking of nesting success on 25 July, neck-banding and brood-counting period has started. 83 more White-fronted geese were supplied with black neck-bands and 53 gosling were also ring with only metal rings. Of Bean Geese 15 birds were neck-banded (one was determined as Taiga Bean Goose Anser fabalis fabalis) and two goslings were metal-ringed only. 33 Barnacle geese were supplied with individually coded plastic leg-rings and 24 Barnacles received only metal rings. 15 chicks of Peregrine falcons, 3 chick of Rough-legged Buzzards and 1 Glaucous Gull received metal rings.
Lower number of raptors
Raptors were nor abundant in 2008, especially in the central part of Kolguev, and quite many pairs of Peregrine falcons either skipped breeding or had small clutches of 1-2 eggs, and lately lost their clutches. Only 2 pairs of Rough-legged Buzzards were nesting in the vicinity of the camp area, and only 1 was successful.
Moderate density of predators
Investigation of moulting flocks
Brood and non-breeding moulting flock counts were conducted during July-August period in entire central part of Kolguev. More than 200 km of counts were made and more then 120 lakes were checked. Number of moulting Bean Geese was rather low in the vicinity of the camp area, and was only found high in the southern part of the hilly area, where also the majority of Bean geese broods were concentrated. Concentrations of up to 100 birds were seen on the lakes. White-fronted geese, on the opposite, were more numerous in central and north-western parts of the hilly area. Concentrations up to 120 nonbreeders and 50 broods were found on the lakes. Moulting non-breeding White-fronted geese were only abundant in the north-western part of Kolguev. Barnacle geese were very abundant in all areas (their number was noticeably higher than in 2007). Concentrations up to 200 birds were seen on Peschanka river and on the lakes.
First non-breeders started to fly after 4 August, and after 10 August they moved around in flocks of 10 – 30 individuals.
15 hours of behavior scans of geese were made on the 3 lakes. The majority of geese fed on Puccinellia on moss bogs of lake valleys. Some of geese fed on aquatic sedge Carex aquatilis on the slopes of lakes valleys on willow moss tundra. Influence of reindeers and arctic foxes on geese behavior was recorded. When reindeers or arctic foxes approached, geese stopped feeding and kept a distance of 100-200 m from the animals. Pecking rates on Puccinella and Carex aquatilis biotope type were measured for 72 birds (broods and nonbreeders). Time budgets of geese feeding on different distances from the lakes were defined for 40 birds. Dropping samples were collected for analyses of feeding behaviour.
The plant data of vegetational surveys are yet to be assessed by coming diploma thesis of Christian, as the large database and taken samples require further lab work and statistical data analysis. It is possible to display the process of accumulating geese near the lakes during brood rearing, but deeper understanding of mechanisms is still to be reached.
Departure from Kolguyev
The helicopter to pick up all expedition participants except Alexander Kondratyev and Elya Zainagutdinova reached Kolguev in time on 19th of August. And during 21st and 22nd all participants left Naryan-Mar towards Moscow, Saint Petersburg and Germany. Alexander and Elya will stay on Kolguev until 10th of September to observe starting migration of geese to the wintering grounds.