Mechanics Of Flight Feathers: Effects Of Captivity?

Mapping Intimacies ◽

10.1101/2020.04.14.038877 ◽

2020 ◽

Author(s):

Steven J. Portugal ◽

Robert L. Nudds ◽

Jonathan A. Green ◽

R. McNeil Alexander ◽

Patrick J. Butler ◽

...

Keyword(s):

Round Trip ◽

Flight Feather ◽

In The Wild ◽

Cyclical Loading ◽

Barnacle Geese ◽

Branta Leucopsis

ABSTRACTFeathers act as aerodynamic cantilevers, and to withstand the prolonged cyclical loading that occurs during flight, feathers must be stiff, lightweight and strong. We experimentally tested the differences in feather structure, primarily stiffness and size, between (a) wild and captive Barnacle Geese Branta leucopsis, and (b) primary feathers dropped during the annual flight feather moult, and those feathers freshly regrown during the moult process. We found that, despite having undergone a 5,000km round-trip migration, flight feathers dropped during moult in the wild geese were stiffer than those measured in the captive geese, both for those dropped during moult and those re-grown. We propose that this may be related to diet or stress in the captive geese.

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Flight feather moult drives minimum daily heart rate in wild geese

Biology Letters ◽

10.1098/rsbl.2018.0650 ◽

2018 ◽

Vol 14 (11) ◽

pp. 20180650 ◽

Cited By ~ 6

Author(s):

Steven J. Portugal ◽

Craig. R. White ◽

Jonathan A. Green ◽

Patrick J. Butler

Keyword(s):

Heart Rate ◽

Annual Cycle ◽

Heart Rate Data ◽

Flight Feather ◽

Individual Bird ◽

Data Loggers ◽

In The Wild ◽

History Of ◽

Barnacle Geese ◽

Wing Moult

Waterfowl undergo an annual simultaneous flight-feather moult that renders them flightless for the duration of the regrowth of the flight feathers. In the wild, this period of flightlessness could restrict the capacity of moulting birds to forage and escape predation. Selection might therefore favour a short moult, but feather growth is constrained and presumably energetically demanding. We therefore tested the hypothesis that for birds that undergo a simultaneous flight-feather moult, this would be the period in the annual cycle with the highest minimum daily heart rates, reflecting these increased energetic demands. Implantable heart rate data loggers were used to record year-round heart rate in six wild barnacle geese ( Branta leucopsis ), a species that undergoes a simultaneous flight-feather moult. The mean minimum daily heart rate was calculated for each individual bird over an 11-month period, and the annual cycle was divided into seasons based on the life-history of the birds. Mean minimum daily heart rate varied significantly between seasons and was significantly elevated during wing moult, to 200 ± 32 beats min −1 , compared to all other seasons of the annual cycle, including both the spring and autumn migrations. The increase in minimum daily heart rate during moult is likely due to feather synthesis, thermoregulation and the reallocation of minerals and protein.

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Use of foster parents in species conservation may cause conflicting objectives: hybridization between Lesser White-fronted Goose Anser erythropus and Barnacle Goose Branta leucopsis

Ornis Svecica ◽

10.34080/os.v31.22430 ◽

2021 ◽

Vol 31 ◽

pp. 125-138

Author(s):

Niklas Liljebäck ◽

Kees Koffijberg ◽

Christine Kowallik ◽

Johan Månsson ◽

Åke Andersson

Keyword(s):

Foster Parents ◽

Species Conservation ◽

Barnacle Goose ◽

Management Actions ◽

Conflicting Objectives ◽

In The Wild ◽

Barnacle Geese ◽

Branta Leucopsis ◽

Anser Erythropus ◽

Over Time

Following the use of Barnacle Geese Branta leucopsis as foster parents in a conservation program for the endangered Lesser White-fronted Goose Anser erythropus in Sweden 1981–1999, mixed breeding pairs of the two species were established in the wild. We find indications that this was related to shared moulting habits of the two species in the Bothnian Sea during late 1990s. Starting in 2003, five mixed pairs produced at least 49 free-flying hybrid offspring until 2013, when the last breeding was confirmed. Reported numbers of hybrids did not increase in parallel to the production of young hybrids over time. After 2013, the number of hybrids started to decrease in Sweden and the Netherlands. Lower numbers of hybrids than expected can partly be explained by management actions taken, but may also be associated with low survival due to genetic outbreeding. Mixed pairs and their offspring entirely adopted the migratory habits of Barnacle Geese, overlapping very little with sites used by Lesser White-fronted Geese. We find no evidence that the hybrids ever posed a serious threat to Lesser White-fronted Geese breeding in Fennoscandia.

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First finding of Tyzzeria parvula (Kotlán, 1933) Klimeš, 1963 (Protozoa: Coccidiida) in Barnacle Geese (Branta leucopsis Bechstein, 1803) on Spitsbergen

Zoosystematica Rossica ◽

10.31610/zsr/2006.15.2.214 ◽

2007 ◽

Vol 15 (2) ◽

pp. 214-214

Author(s):

O.V. Dolnik ◽

M.J.J.E. Loonen

Keyword(s):

The Arctic ◽

First Finding ◽

Breeding Grounds ◽

Barnacle Geese ◽

Branta Leucopsis

This is the first finding of Tyzzeria sp. in Barnacle Geese, as well as the first documentation of Tyzzeria parasites on Spitsbergen. Since goslings were highly infected, it can be concluded that transmission of Tyzzeria parasites takes place on the arctic breeding grounds.

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