Pleistocene ducks of the Old Crow Basin, Yukon Territory, Canada

1991 ◽  
Vol 28 (10) ◽  
pp. 1561-1571 ◽  
Author(s):  
Gerald R. Fitzgerald
Keyword(s):  
Boreal Forest ◽  
Common Species ◽  
Yukon Territory ◽  
Common Eider ◽  
Somateria Mollissima ◽  
The Past ◽  
The Common ◽  
Melanitta Fusca ◽  
Clangula Hyemalis

Thirteen species of ducks, ranging in age from ?latest Illinoian to Holocene, have been identified from the Old Crow Basin. The most common species in the collection is the Oldsquaw (Clangula hyemalis), followed by the White-winged Scoter (Melanitta fusca). The genus Anas (six species) is well represented. The Ring-necked Duck (Aythya collaris) and the Black Scoter (Melanitta nigra) also occupied the area in the past. This shows that good habitat for ducks has existed in the area at times since the ?Illinoian and supports environmental reconstructions for the area suggesting that ?Sangamon conditions were as warm as, or warmer than, today, with ponds and streams and pockets of boreal forest. There is also evidence for inland migration of the Common Eider (Somateria mollissima).

Female sociality in the common eider duck during brood rearing

1982 ◽  
Vol 60 (12) ◽  
pp. 3326-3331 ◽  
Author(s):  
J. K. Schmutz ◽  
R. J. Robertson ◽  
F. Cooke
Keyword(s):  
Maternal Care ◽  
Adaptive Significance ◽  
Common Eider ◽  
Somateria Mollissima ◽  
Brood Rearing ◽  
The Common ◽  
Nutrient Reserves ◽  
Prolactin Hormone

This study investigates the potential adaptive significance of the behavior of female common eider ducks (Somateria mollissima) which have no young of their own ("aunts") but accompany other females and young. "Aunts" exhibited ambivalent aggression and protection toward ducklings. There was no evidence that the presence of "aunts" enhanced the survival of the ducklings they accompanied. Both females which had their clutch removed and females which had not laid eggs behaved as "aunts." The level of circulating prolactin hormone in "aunts" was lower than in incubating females and similar to the basal level of males. We therefore rejected the hypothesis that maternal care was misdirected during hormonal adjustment from breeding to nonbreeding. We suggest that "aunts" which have lost a clutch or brood, spend some time feeding away from the colony, and then return to the nesting grounds after replenishing their nutrient reserves. Upon returning, "aunts" may select sites for nesting in future years. During this time, they are temporarily attracted to broods. We propose that "aunts" flock and fend off predators during an attack in an attempt to seek safety in a flock rather than to protect ducklings of other females.

Sex and age structures of the White Sea endemic population of the common eider Somateria mollissima

2010 ◽  
Vol 435 (1) ◽  
pp. 435-437 ◽  
Author(s):  
Yu. V. Krasnov ◽  
M. V. Gavrilo ◽  
A. A. Shavykin ◽  
P. S. Vashchenko
Keyword(s):  
White Sea ◽  
Common Eider ◽  
Somateria Mollissima ◽  
The White Sea ◽  
Endemic Population ◽  
The Common ◽  
Age Structures

scholarly journals The importance of offshore areas in southern Öresund, Sweden, for staging and wintering sea ducks

Ornis Svecica ◽  
2015 ◽  
Vol 25 (1–2) ◽  
pp. 24-39
Author(s):  
Martin Green ◽  
Leif Nilsson
Keyword(s):  
Somateria Mollissima ◽  
Time Pattern ◽  
Sea Ducks ◽  
National Importance ◽  
Mergus Merganser ◽  
Winter Peak ◽  
International Importance ◽  
Melanitta Fusca ◽  
Clangula Hyemalis ◽  
General Time

The occurrence of wintering and spring-staging sea ducks in the southern part of Swedish Öresund was surveyed from air and ship during the period 2001–2011. Altogether 22 air and 20 boat surveys were made during the months November–May and here we present the results regarding five commonly recorded sea ducks. We present the numbers recorded and the general time pattern of occurrence during winter and spring in the area. Recorded numbers are then used for evaluating the importance of the area, both in relation to national wintering totals as well as to international (Baltic) totals. Southern Swedish Öresund is of no larger importance for Long-tailed Duck Clangula hyemalis in winter and spring. The area is however of national importance for both Velvet Scoter Melanitta fusca and Common Scoter Melanitta nigra in winter. Peak numbers of Common Scoters do also reach international importance. Southern Swedish Öresund is of large national and international importance for both wintering and spring-staging Eider Somateria mollissima and Red-breasted Merganser Mergus merganser.

scholarly journals Helminthes of the Common Eider (Somateria mollissima) on the Eastern Murman, its impact on the digestive activity and physiological state

2019 ◽  
Vol 487 (1) ◽  
pp. 107-110
Author(s):  
M. M. Kuklina ◽  
V. V. Kuklin
Keyword(s):  
Small Intestine ◽  
Species Composition ◽  
Intestinal Mucosa ◽  
Physiological State ◽  
Common Eider ◽  
Somateria Mollissima ◽  
Control Parameters ◽  
Hematological Indices ◽  
The Common ◽  
Digestive Activity

An ecological and physiological study of Common Eider (Somateria mollissima) nesting on the coast of Eastern Murman was carried out. The species composition of helminthofauna of birds and the quantitative parameters of the infection were studied. It is established that trematodes of the genus Microphallus, three species of cestodes - Lateriporus teres (Cestoda: Dilepididae), Fimbriarioides intermedia (Cestoda: Hymenolepididae), Microsomacanthus diorchis (Cestoda: Hymenolepididae) and one species of acanthocephalan - Polymorphus phippsi (Palaeacanthocephala: Polymorphidae) parasitized in the small intestine of Common Eider. It is shown that the activity of proteases decreased at the locations of F. intermedia and M. diorchis in the intestines of birds, with infestation with the acanthocephalan P. phippsi, on the contrary, increased. The activity of glycosides in the intestinal mucosa was reduced in comparison with the control values by infection cestodes M. diorchis. There was an increase in the values of hematological indices in infected individuals relative to the control parameters.

An ultrastructural study of reproduction in the parthenogenetic metacercariae of Cercaria margaritensis Ching, 1982 (Digenea: Gymnophallidae)

Parasitology ◽  
2003 ◽  
Vol 126 (3) ◽  
pp. 261-271 ◽  
Author(s):  
S. W. B. IRWIN ◽  
K. V. GALAKTIONOV ◽  
I. I. MALKOVA ◽  
D. H. SAVILLE ◽  
S. M. FITZPATRICK
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Embryo Development ◽  
Ultrastructural Study ◽  
Definitive Host ◽  
Parent Body ◽  
Common Eider ◽  
Somateria Mollissima ◽  
Transmission Electron ◽  
The Common

The parthenogenetic metacercarial stages of the gymnophallid trematode Cercaria margaritensis are found in the extrapallial cavity of the subtidal prosobranch mollusc Margarites helicinus. The primary metacercariae (M1) produce second-generation metacercariae (M2) which become independent and give rise to M3 metacercariae which are infective to the definitive host, the common eider (Somateria mollissima). This study used transmission electron microscopy to follow the development of M2 inside M1 organisms and M3 inside M2 organisms. The process is similar in both cases with embryos developing from individual cells from the parent body walls. In each case the brood sac was divided into brood chambers by multilaminated cells and both M2 and M3 embryos developed inside embryonic membranes that originated from specialized blastomeres. The tegument of M2 and M3 embryos developed in a similar manner underneath the embryonic membrane. Both the multilaminated cells and the embryonic membranes possessed features that indicated that they are involved in transport of nutrients. It is suggested that the continuous nature of M2 and M3 embryo development may well be similar to that postulated for ancestral digeneans.

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