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^ШХР: П 3555 2010 7(2)
^АВТ: Коузов С.А. (Санкт-Петербургский гос. университет).; Кравчук А.В.
^ЗГЛ: Размножение серой утки (Anas strepera L.) в Ленинградской области = Gadwall breeding in Leningrad region
^ВЫХ: Вестник охотоведения, 2010; Т.7,N 2. - С. 254-258
^ДАТ: 2010
^ПРМ: Рез. англ..-Библиогр.:с.257
+Реферат:

^РЕФ: В работе обобщаются результаты наблюдений авторов в восточной части Финского залива и имеющиеся литературные данные. Приводятся материалы по срокам и скорости расселения серой утки в Ленинградской области, распространению в регионе, срокам прилета и размнонжения, биотопическому распределению, величине кладок и размерам яиц, биотопическому распределению и поведению выводков, репродуктивному успеху серой утки.

aref2 2 In the mid-20 th century, the only occasion of Gadwall (Anas strepera L.) nesting was reported from Rakovye Lakes in 1966 (Molis, 1967). The main wave of dispersal began in the 1990s and proнceeded along the Gulf of Finland southern coast via Kurgalsky Peninsula, where solitary birds apнpeared regularly in 1988-1994. In 1995, we observed 9 breeding occasions on the peninsula western coast; further on, we found 10 to 24 clutches there every year. In 1997, Gadwall started breeding on Seskar Island. Today, Gadwall is a common breeder at the Neva Bay, on Kotlin Island, at Lahtinsky and Sestroretsky Razlivs, on Beryozovye Islands, on islands and shores of the Vyborg Bay, and at some lakes of the Karelian Isthmus (Melkovodnoye and Rakovye Lakes), Ropshinskiye ponds; it is now regularly sighted also in the south-western part of Ladoga. Gadwall sticks to large eutrophic shallow-water reservoirs heavily overgrown with emergent vegetaнtion. The main reserve for the species is Kurgalsky Peninsula, where 151 Gadwall nests were found in 1995-1999 and 2005-2009. Most birds there start laying eggs on 16.05-05.06. (84.92%, n=126), but some clutches may be formed after May 5 th and until mid-June. A normal clutch size is 7-11 eggs, the mean being 9.27±1.28 (n=127). Egg dimensions are 48.9-59.1x34.9-40.7, mean - 53.12±2.12x37.77±1.79 (n=207). Mean clutch size on abundance rise yeas (1996, 1998-1999 and 2007) was slightly smaller (9.13±1.29, n=73) than in other seasons (9.48±1.08, n=54). The clutches started after 26.05 (8.79+0.96, n=15) were smaller than earlier ones (9.55+1.09, n=18). The incubation success for Gadwall in 2006-2009 was 85.37% (n=383 eggs), and most of the egg loss (78.57%, n=56) was due to discord of their laying in communal clutches or beнcause the incubating female abandoned such clutches. The proportion of communal clutches was high (18.46%, n=65 in 2006-2009): with Tufted Duck (8 nests), less often with Red-breasted Merнganser and Goosander, Garganey or conspecific (1 nest each). The broods stay reticent in emergent reed stands. One to three communal Gadwall or Gad-wall/Tufted Duck broods are found every year. Some 2-3-week-old Gadwall ducklings regularly stay apart from the broods. Part of the broods move to overflow land soon after taking to water, crossing 1-2 km of open water. Survival to fledging in 2006-2009 was 64.52% (n=327). Total reproductive success in Gadwall on Kurgalsky Peninsula in these years was 55.09 % (n=383).

^TRN: 1176522
^ВИД: Статья из журнала
^ЯЗК: Русский
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