Sea-ice and density-dependent factors affecting foraging habitat and behaviour of Adélie penguins throughout the breeding season

Sentinel species, like Adélie penguins, have been used to assess the impact of environmental changes, and their link with sea ice has received considerable attention. Here, we tested if foraging Adélie penguins from 2 colonies in East Antarctica target the distant sea-ice edge or take advantage of closer open waters that are readily available near their colony. We examined the foraging behaviour of penguins during the incubation trips of females in 2016 and males in 2017, using GPS tracking and diet data in view of daily sea-ice data and bathymetry. In 2016-2017, sea-ice cover was extensive during females’ trips but flaw leads and polynyas were close to both study sites. Sea ice receded rapidly during males’ trips in 2017-2018. Despite close open water near both colonies in both years, females and males preferentially targeted the continental slope and the sea-ice edge to forage. In addition, there was no difference in the diet of penguins from both colonies: all penguins fed mostly on Antarctic krill and males also foraged on Antarctic silverfish. Our results highlight the importance of the sea-ice edge for penguins, an area where food abundance is predictable. It is likely that resource availability was not sufficient in closer open water areas at such an early stage in the breeding season. The behaviours displayed by the penguins from both colonies were similar, suggesting a common behaviour across colonies in Terre Adélie, although additional sites would be necessary to confirm this hypothesis.

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Scale matters: sea ice and breeding success of Adélie penguins

Polar Biology ◽

10.1007/s00300-019-02531-2 ◽

2019 ◽

Vol 42 (7) ◽

pp. 1405-1410 ◽

Cited By ~ 1

Author(s):

Emmanuelle Barreau ◽

Yan Ropert-Coudert ◽

Karine Delord ◽

Christophe Barbraud ◽

Akiko Kato-Ropert

Keyword(s):

Sea Ice ◽

Breeding Success ◽

Adélie Penguins

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The Weddell seals of Larsen Harbour, South Georgia: a unique but apparently declining colony

Polar Record ◽

10.1017/s0032247414000953 ◽

2015 ◽

Vol 51 (6) ◽

pp. 667-671 ◽

Cited By ~ 1

Author(s):

Robert Burton

Keyword(s):

Sea Ice ◽

Breeding Season ◽

Small Population ◽

Single Observation ◽

South Georgia ◽

Weddell Seals ◽

Cruise Ships

ABSTRACTThe small population of Weddell seals at Larsen Harbour, South Georgia, is isolated from the rest of the species and is unique because nearly all pups are born on land rather than on sea-ice. Observations of seals in Larsen Harbour during the breeding season are summarised. These have been infrequent until cruise ships started to visit. With often only a single observation in a year, accurate estimates of pup production are impossible but it appears that the population has decreased over the last three decades.

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Factors affecting breeding season survival of red-headed woodpeckers in South Carolina

Journal of Wildlife Management ◽

10.1002/jwmg.282 ◽

2011 ◽

Vol 76 (2) ◽

pp. 328-335 ◽

Cited By ~ 21

Author(s):

John C. Kilgo ◽

Mark Vukovich

Keyword(s):

South Carolina ◽

Breeding Season ◽

Factors Affecting

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Littoral Stratification in Growth form and Fecundity of the Rock Barnacle, Semibalanus Balanoides

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315400028733 ◽

1988 ◽

Vol 68 (4) ◽

pp. 591-599 ◽

Cited By ~ 2

Author(s):

R. W. Rangeley ◽

M. L. H. Thomas

Keyword(s):

Intertidal Zone ◽

Growth Form ◽

Base Length ◽

Nucella Lapillus ◽

Semibalanus Balanoides ◽

Factors Affecting ◽

Intertidal Zones ◽

Density Dependent ◽

Low Incidence ◽

High Intertidal Zone

The population dynamics of rock barnacles, Semibalanus balanoides (L.), residing in low and high intertidal zones are affected by conspicuously different factors. The barnacle population in the high intertidal zone tends to show longterm stability due to a low incidence of both predation and interspecific competition. Wave exposure, desiccation and intraspecific competition are more important factors affecting abundance and size distribution in this zone (Menge, 1976). In the low intertidal zone, barnacle predation by the dogwhelk, Nucella lapillus (L.) is intense (Menge, 1976) and both the adults and larvae are smaller than in the high intertidal zone (Barnes, 1953). The growth form of S. balanoides is density dependent with taller, more columnar individuals predominating at high densities and short conical barnacles at low densities. Lower fecundity of conical individuals may be due to lower internal shell volume compared with columnar forms (Wethey, 1984). Fecundity increases both with increasing age and base length (Arnold, 1977) and is positively density dependent (Wethey, 1984).

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Field margins as foraging habitat for skylarks (Alauda arvensis) in the breeding season

Agriculture Ecosystems & Environment ◽

10.1016/j.agee.2013.03.001 ◽

2013 ◽

Vol 170 ◽

pp. 10-15 ◽

Cited By ~ 17

Author(s):

M.W. Kuiper ◽

H.J. Ottens ◽

L. Cenin ◽

A.P. Schaffers ◽

J. van Ruijven ◽

...

Keyword(s):

Breeding Season ◽

Field Margins ◽

Foraging Habitat ◽

Alauda Arvensis

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Incubation temperatures of the northern shoveler

Canadian Journal of Zoology ◽

10.1139/z79-133 ◽

1979 ◽

Vol 57 (5) ◽

pp. 1052-1056 ◽

Cited By ~ 21

Author(s):

Alan D. Afton

Keyword(s):

Regression Analysis ◽

Body Temperature ◽

Multiple Regression Analysis ◽

Cooling Rate ◽

Breeding Season ◽

Factors Affecting ◽

Ground Temperatures ◽

Air Temperatures ◽

Temperature Records ◽

Incubation Temperatures

Egg air cell and nest air temperatures, measured in nests of wild northern shovelers near Delta, Manitoba, Canada, averaged 36.1 and 32.0 °C, respectively. Mean brood patch temperature of one captive incubating hen was 39.5 °C. Body temperature of 16 wild incubating hens averaged 41.1 °C. An egg cooling rate of 0.22 °C/1 °C h−1 was calculated from temperature records of 170 incubation recesses. Factors affecting egg cooling during recesses were investigated using multiple regression analysis. Statements in the literature that incubation by Anatidae begins upon termination of laying are not supported by available data. Incubation by waterfowl, as in passerines, apparently begins gradually during the laying period. Air and ground temperatures, by influencing egg cooling rates during incubation, may have been important ultimate factors determining the breeding range and timing of the breeding season for the northern shoveler.

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Do flocks of great cormorants and goosanders avoid spatial overlap in foraging habitat during the non-breeding season?

Aquatic Ecology ◽

10.1007/s10452-017-9630-7 ◽

2017 ◽

Vol 51 (3) ◽

pp. 473-483

Author(s):

Łukasz Kajtoch ◽

Peter Lešo ◽

Marcin Matysek ◽

Mirosław Kata ◽

Stanisław Gacek ◽

...

Keyword(s):

Breeding Season ◽

Foraging Habitat ◽

Spatial Overlap ◽

Great Cormorants

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Solidification of Sea Ice

Journal of Glaciology ◽

10.1017/s0022143000018050 ◽

1960 ◽

Vol 3 (28) ◽

pp. 745-761 ◽

Cited By ~ 21

Author(s):

Clyde M. Adams ◽

David N. French ◽

W. David Kingery

Keyword(s):

Sea Ice ◽

Solidification Process ◽

Ice Formation ◽

Transient Heating ◽

Cold Air ◽

Factors Affecting ◽

Heating And Cooling

AbstractThermal considerations affecting the rate of formation of sea ice are discussed showing the effects of the major variables. The natural solidification process (freezing downward from contact with cold air) is contrasted with freezing of layers cast on the surface of sea ice. Transient heating and cooling of solid ice during and after flooding are analyzed. Procedures for maximizing the rate of ice formation and minimizing base-ice heating are discussed, along with factors affecting brine segregation.

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