OVERLAP IN DIETS AND FORAGING OF COMMON MURRES (URIA AALGE) AND RHINOCEROS AUKLETS (CERORHINCA MONOCERATA) AFTER THE BREEDING SEASON

AbstractCommon Murres (Uria aalge; hereafter “murres“) and Rhinoceros Auklets (Cerorhinca monocerata; hereafter “auklets“) breed and forage sympatrically over much of their range. They have similar diets during the breeding season, which suggests that they partition prey during the breeding season by foraging (1) at different locations, (2) at different times of day, (3) at different water depths, (4) on different proportions of the same prey species, or (5) some combination of the four. We examined possible mechanisms of niche partitioning during late summer and fall in Puget Sound, Washington, in 1993-1996. Murres and auklets fed mainly on Pacific herring (Clupea pallasii, occurring in 74.2% and 48.1%, respectively, of gastrointestinal tracts with contents), Pacific sand lance (Ammodytes hexapterus; 45.8% and 62.3%), and salmonid (Oncorhynchus spp.) species (21.9% and 9.7%). Auklets also consumed considerable amounts of threespine stickleback (Gasterosteus aculeatus; 26.6%). Murres and auklets did not differ significantly (1) in their diet (between age classes or sexes of either species, or among years); (2) in mean lengths of Pacific herring (101 and 109 mm, respectively) and Pacific sand lance (82 and 86 mm) they consumed; or (3) in the mean depth (7–8 m) at which they were entangled in gill nets. Dietary diversity was low, with most gastrointestinal tracts containing only one or two prey species in both murres and auklets. Murres were caught and therefore presumably feed more frequently in the afternoon and evening; whereas auklets were entangled more often in early morning. We found differences between murres and auklets in the diel chronology of prey taken, which may partly explain how murres and auklets coexist during the breeding season and months thereafter, prior to auklet emigration from Puget Sound.Chevauchement du Régime Alimentaire et de la Quête Alimentaire chez Uria aalge et Cerorhinca monocerata après la Saison de Reproduction

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A Comparison of Feeding Areas Used by Individual Common Murres (Uria aalge), Razorbills (Alca torda) and an Atlantic Puffin (Fratercula arctica) during the Breeding Season

Colonial Waterbirds ◽

10.2307/1521416 ◽

1990 ◽

Vol 13 (1) ◽

pp. 16 ◽

Cited By ~ 31

Author(s):

S. Wanless ◽

M. P. Harris ◽

J. A. Morris

Keyword(s):

Breeding Season ◽

Uria Aalge ◽

Alca Torda ◽

Fratercula Arctica ◽

Common Murres ◽

Atlantic Puffin

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Ecological interactions and habitat modification in nesting Common Murres, Uria aalge

Bird Conservation International ◽

10.1017/s0959270900003154 ◽

1996 ◽

Vol 6 (3) ◽

pp. 261-269 ◽

Cited By ~ 8

Author(s):

Julia K. Parrish ◽

Robert T. Paine

Keyword(s):

Reproductive Output ◽

Habitat Modification ◽

Haliaeetus Leucocephalus ◽

Uria Aalge ◽

Ecological Interactions ◽

Bald Eagles ◽

Predator Removal ◽

Common Murre ◽

Corvus Caurinus ◽

Common Murres

SummarySeabird populations suffer from a variety of natural and human-induced sources of mortality and loss of lifetime reproductive output. On the outer coast of Washington State, Common Murre Uria aalge populations have been in decline for approximately the last decade and are currently reproductively active only at Tatoosh Island. These murres nest in two basic habitat types: crevices (25% of the population) and larger cliff-top subcolonies (75%). Murres in cliff-top subcolonies have suffered dramatic reductions in reproductive success in recent years relative to conspecifics nesting in the crevices, primarily due to egg predation by Glaucous-winged Gulls Larus glaucescens and Northwestern Crows Corvus caurinus, facilitated by the presence of Bald Eagles Haliaeetus leucocephalus. Because predator removal is not feasible and creation of additional crevice habitat is difficult, expensive and potentially ineffective, we have designed a temporary habitat modification (the “silk forest”) which replaces the natural vegetation cover and modifies the interaction between murres and eagles. Within the test subcolony, murres nesting under and immediately adjacent to the silk forest produced nearly twice as many eggs per square metre as their conspecifics nesting in adjacent exposed-ground areas.

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Investigating post-breeding moult locations and diets of Common Guillemots (Uria aalge) in the North Sea using stable isotope analyses

10.1101/2020.09.01.276857 ◽

2020 ◽

Author(s):

Alec P. Christie

Keyword(s):

Stable Isotope ◽

Breeding Season ◽

North Sea ◽

Cost Effective ◽

Uria Aalge ◽

Age Classes ◽

Stable Isotope Analyses ◽

The North ◽

The North Sea ◽

Isotope Analyses

AbstractSeabird movements and diet during the non-breeding season are poorly studied, yet understanding these aspects of seabird ecology is extremely important to effectively conserve these protected species. Stable isotope analyses (SIA) provide a cost-effective solution to filling these knowledge gaps, yielding information on diet and foraging locations of animals. This study aimed to use SIA to investigate whether Common Guillemots (Uria aalge) from different age classes and locations in the UK had contrasting diets and foraging areas during the post-breeding moult (July-September). SIA of secondary feathers and a newly-developed North Sea isoscape were used to identify the likeliest foraging areas and diets of deceased guillemots recovered from beaches in eastern Scotland and mixed fisheries in Cornwall and the Celtic Sea. Overall, guillemots foraged widely in the western, eastern and southern North Sea, consuming a variety of clupeid, gadoid and invertebrate prey. There were negligible dietary differences between age classes and birds from different recovery locations. Juveniles showed a wider range in foraging areas, but both age classes foraged in similar parts of the North Sea. Guillemots recovered from Scotland may have foraged further north, only overlapping with guillemots recovered from the southwestern UK in the southern and eastern North Sea. Their winter recovery locations also implied that they exhibited different movement strategies during the non-breeding season, meriting further investigation. Conservation efforts should target foraging areas in the southern and eastern North Sea which are highly threatened by gillnet fishing, shipping traffic and oil infrastructure.

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Exceptional variation in the appearance of Common Murre eggs reveals their potential as identity signals

The Auk ◽

10.1093/ornithology/ukab049 ◽

2021 ◽

Author(s):

Tim R Birkhead ◽

Jamie E Thompson ◽

Amelia R Cox ◽

Robert D Montgomerie

Keyword(s):

Uria Aalge ◽

Quantitative Evidence ◽

Breeding Group ◽

Common Murre ◽

Trimodal Distribution ◽

Common Murres ◽

Egg Traits ◽

Breeding Groups ◽

Different Parts

Abstract We studied the ground colors and maculations of 161 Common Murre (Uria aalge) eggs laid by 43 females in 3 small breeding groups on the cliffs of Skomer Island, Wales, in 2016–2018. Both the colors and maculations varied much more among than within females, providing quantitative evidence for the egg traits that might facilitate the parents’ ability to identify their own eggs on the crowded breeding ledges where the density is typically ~20 eggs m–2. Ground colors had a trimodal distribution of hue values (whitish to pale brown, pale blue, or vivid blue-green) and maculations ranged from none to complex squiggles and blotches. The eggs laid by each female in different years were similar to one another, and replacement eggs laid by females within years were also more similar to their first egg than to other eggs in the same breeding group. Egg appearance did not differ among the 3 breeding groups that we studied. Our findings thus support anecdotal observations that, within and between years, female Common Murres lay eggs that have similar ground colors and maculations. We do not, however, find evidence that there is much difference among the eggs laid in different parts of a colony.

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Post-fledging migration of common murres Uria aalge in the Baltic Sea: management implications

Ecography ◽

10.1111/j.1600-0587.1999.tb00497.x ◽

1999 ◽

Vol 22 (3) ◽

pp. 233-239 ◽

Cited By ~ 9

Author(s):

Olof Olsson ◽

Thord Fransson ◽

Kjell Larsson

Keyword(s):

Baltic Sea ◽

Uria Aalge ◽

The Baltic Sea ◽

Management Implications ◽

Common Murres ◽

The Baltic

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Restriction fragment analysis of mitochondrial DNA in Common Murres, Uria aalge, from four Norwegian seabird colonies

Canadian Journal of Zoology ◽

10.1139/z91-221 ◽

1991 ◽

Vol 69 (6) ◽

pp. 1577-1584 ◽

Cited By ~ 13

Author(s):

Truls Moum ◽

Kjell Einar Erikstad ◽

Eirik Bjørklid

Keyword(s):

Mitochondrial Dna ◽

Restriction Analysis ◽

Sequence Divergence ◽

Ancestral Population ◽

Population Divergence ◽

Uria Aalge ◽

Population Bottlenecks ◽

Geographic Population ◽

Common Murres ◽

Seabird Colonies

Alcid species (auks) breed in a restricted number of large seabird colonies and are considered highly philopatric. Mitochondrial DNA (mtDNA) of Common Murres, Uria aalge, from four Norwegian colonies was investigated by restriction analysis to assess the amount of geographic population structure and genetic variability in a colonial breeder. Eleven restriction endonucleases revealed 13 mtDNA genotypes among 51 individuals. Genetic diversity was low, with an average of 0.11% (range 0.0–0.55%) sequence divergence between all individuals. Population divergence within the surveyed region seems to be minimal, demonstrated by the low levels of sequence divergence between colonies and lack of spatial structuring of genotypes. Such results can be expected if birds originated from a smaller ancestral population during glaciation, and may have been reinforced by repeated population bottlenecks and considerable gene flow between colonies.

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Extra-pair copulations in common murres I: a mate attraction strategy?

Behaviour ◽

10.1163/156853906778691559 ◽

2006 ◽

Vol 143 (10) ◽

pp. 1241-1262 ◽

Cited By ~ 3

Author(s):

Maureen L. Cameron-Macmillan ◽

Carolyn J. Walsh ◽

Sabina I. Wilhelm ◽

Anne E. Storey

Keyword(s):

Reproductive Success ◽

Uria Aalge ◽

Success Rates ◽

High Quality ◽

Mate Attraction ◽

Extra Pair Paternity ◽

Socially Monogamous ◽

Common Murres ◽

Breeding Seasons

AbstractWe investigated the behavioural context of pair (PCs) and extra-pair copulations (EPCs) in individually-marked socially-monogamous, long-lived seabirds, common murres (Uria aalge). Since forced EPCs have been documented for this species, we first examined which sex controls successful (cloacal contact achieved) copulation. The finding that all successful copulations required female cooperation and crouching suggested that benefits of successful EPCs accrue primarily to females. In a group of murres for which paternity analyses indicated no extra-pair paternity, behavioural observations over five breeding seasons showed that individual females engaged in EPCs primarily under two circumstances: (1) before they were reunited with their mates, and (2) when they were in the process of re-pairing. There was no such relationship between EPCs and re-pairing for males. Successful EPCs occurred with familiar neighboring males of apparent high quality, indicated by their high ledge attendance and prior reproductive success rates. Thus, EPCs may be used by females to attract potential high quality mates in situations where females are attempting to re-pair as a result of divorce or mate death.

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