scholarly journals STUDIES OF THE TIME BUDGET AND DAILY ACTIVITY OF COMMON EIDER SOMATERIA MOLLISSIMA DURING INCUBATION

2021 ◽  
Author(s):  
GRIGORI M. TERTITSKI ◽  
EVGENY V. SEMASHKO ◽  
ALEXANDER E. CHERENKOV ◽  
VLADIMIR Y. SEMASHKO

In the Common Eider Somateria mollissima, only females incubate the clutch over a period of 25–28 days. Determining their schedule of nest absence, how long they are away, how often, and where they go can be problematic. They must also avoid nest predation while tending to their own needs. We used geolocators to investigate the behavior of incubating females on forested islands in Dolgaya Guba Bay (65°03′N, 035°47′E), White Sea, Russia. Data were obtained for 12 females: three in 2015 and 2016, four in 2017, and two in 2018. During the entire incubation period, females left their nests for the sea 12–28 times. The average duration at sea was 331.0 ± 53.8 min, including 261.1 ± 47.9 min during the darkest hours in otherwise 24-hour daylight. The patterns are similar to those of eiders nesting in lower, nonpolar latitudes, where nights are dark.

2010 ◽  
Vol 435 (1) ◽  
pp. 435-437 ◽  
Author(s):  
Yu. V. Krasnov ◽  
M. V. Gavrilo ◽  
A. A. Shavykin ◽  
P. S. Vashchenko

2009 ◽  
Vol 427 (1) ◽  
pp. 343-345 ◽  
Author(s):  
Yu. V. Krasnov ◽  
G. A. Shklyarevich ◽  
Yu. I. Goryaev

1982 ◽  
Vol 60 (12) ◽  
pp. 3326-3331 ◽  
Author(s):  
J. K. Schmutz ◽  
R. J. Robertson ◽  
F. Cooke

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.


2019 ◽  
Vol 487 (1) ◽  
pp. 107-110
Author(s):  
M. M. Kuklina ◽  
V. V. Kuklin

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.


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

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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