Dynamics of Antarctic penguin populations in relation to inter-annual variability in sea ice distribution

Trathan, Philip N.; Croxall, J. P.; Murphy, Eugene J.

doi:10.1007/s003000050059

Cited by 34 publications

(65 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…These were 1981 (sea ice data not shown, but see Lishman, 1985;Trathan et al, 1996), and years 1988 and 1998. In 1998 the persistence of ice cover during the chinstrap-breeding season prevented the access of researchers to colonies and the data are thus unavailable.…”

Section: Trends In Penguin Populations and Environment Forcingmentioning

confidence: 97%

“…We considered the total number of breeding pairs as the sum of pairs in different breeding assemblages or subcolonies, each of which was counted every breeding season throughout the time series. Additional details on data collection can be found in Croxall et al (1988) and Trathan et al (1996). Penguin subcolonies were defined as discrete assemblages of contiguous nests.…”

Section: Datamentioning

confidence: 99%

“…The three pygoscelid penguins, Adélie (Pygoscelis adeliae), chinstrap (P. antarctica), and gentoo (P. papua) penguins, are all affected by changes in sea ice extent (Fraser et al, 1992;Trathan et al, 1996;Ainley et al, 1998;Wilson et al, 2001;Clarke et al, 2002;Kato et al, 2002;Smith et al, 2003). The gentoo penguin is mainly subAntarctic with a subspecies confined to the Antarctic Peninsula.…”

Section: Introductionmentioning

confidence: 99%

“…This adaptation is mediated by specific differences in foraging and migratory behaviour, life history tactics and breeding chronology. As their preferred habitat is largely defined by the presence/absence of sea ice (Lishman, 1985;Trivelpiece et al, 1987;Trathan et al, 1996;Clarke et al, 2002;Lynnes et al, 2004), the links between sea ice and penguin population process are key to understanding population changes that occur as a consequence of regional warming.…”

Section: Introductionmentioning

confidence: 99%

“…Extensive ice cover in late spring and early summer is a physical barrier preventing the access of penguins with lower ice tolerances to the breeding colonies (Lishman, 1985;Fraser et al, 1992;Trathan et al, 1996;Ainley et al, 1998;Wilson et al, 2001;Rombolá et al, 2003;Lynnes et al, 2004). On the other hand, regional sea ice variability limits the abundance of Antarctic krill (Euphausia superba), a dominant component of the penguin diet in some regions (Fraser et al, 1992;Fraser & Trivelpiece, 1996;Fraser & Patterson, 1997;Lynnes et al, 2002, Fraser & Hoffman, 2003Lynnes et al, 2004).…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

Contrasting population changes in sympatric penguin species in association with climate warming

Forcada

Trathan

Reid

et al. 2006

Global Change Biology

Self Cite

202

230

View full text Add to dashboard Cite

Climate warming and associated sea ice reductions in Antarctica have modified habitat conditions for some species. These include the congeneric Adélie, chinstrap and gentoo penguins, which now demonstrate remarkable population responses to regional warming. However, inconsistencies in the direction of population changes between species at different study sites complicate the understanding of causal processes. Here, we show that at the South Orkney Islands where the three species breed sympatrically, the less iceadapted gentoo penguins increased significantly in numbers over the last 26 years, whereas chinstrap and Adélie penguins both declined. These trends occurred in parallel with regional long-term warming and significant reduction in sea ice extent. Periodical warm events, with teleconnections to the tropical Pacific, caused cycles in sea ice leading to reduced prey biomass, and simultaneous interannual population decreases in the three penguin species. With the loss of sea ice, Adélie penguins were less buffered against the environment, their numbers fluctuated greatly and their population response was strong and linear. Chinstrap penguins, considered to be better adapted to ice-free conditions, were affected by discrete events of locally increased ice cover, but showed less variable, nonlinear responses to sea ice loss. Gentoo penguins were temporarily affected by negative anomalies in regional sea ice, but persistent sea ice reductions were likely to increase their available niche, which is likely to be substantially segregated from that of their more abundant congeners. Thus, the regional consequences of global climate perturbations on the sea ice phenology affect the marine ecosystem, with repercussions for penguin food supply and competition for resources. Ultimately, variability in penguin populations with warming reflects the local balance between penguin adaptation to ice conditions and trophic-mediated changes cascading from global climate forcing.

show abstract

Section: Trends In Penguin Populations and Environment Forcingmentioning

confidence: 97%

Section: Datamentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Contrasting population changes in sympatric penguin species in association with climate warming

Forcada

Trathan

Reid

et al. 2006

Global Change Biology

Self Cite

202

230

View full text Add to dashboard Cite

show abstract

Temporal variation in trophic relationships among three congeneric penguin species breeding in sympatry

Tarroux

Lydersen

Trathan

et al. 2018

Ecology and Evolution

View full text Add to dashboard Cite

Penguins are a monophyletic group in which many species are found breeding sympatrically, raising questions regarding how these species coexist successfully. Here, the isotopic niche of three sympatric pygoscelid penguin species was investigated at Powell Island, South Orkney Islands, during two breeding seasons (austral summers 2013–2014 and 2015–2016). Measurements of carbon (δ13C) and nitrogen (δ15N) stable isotope ratios were obtained from blood (adults) or feather (chicks) samples collected from Adélie Pygoscelis adeliae, chinstrap P. antarctica, and gentoo P. papua penguins. Isotopic niche regions (a proxy for the realized trophic niches) were computed to provide estimates of the trophic niche width of the studied species during the breeding season. The isotopic niche regions of adults of all three species were similar, but gentoo chicks had noticeably wider isotopic niches than the chicks of the other two species. Moderate to strong overlap in isotopic niche among species was found during each breeding season and for both age groups, suggesting that the potential for competition for shared food sources was similar during the two study years, although the actual level of competition could not be determined owing to the lack of data on resource abundance. Clear interannual shifts in isotopic niche were seen in all three species, though of lower amplitude for adult chinstrap penguins. These shifts were due to variation in carbon, but not nitrogen, isotopic ratios, which could indicate either a change in isotopic signature of their prey or a switch to an alternative food web. The main conclusions of this study are that (1) there is a partial overlap in the isotopic niches of these three congeneric species and that (2) they responded similarly to changes that likely occurred at the base of their food chain between the 2 years of the study.

show abstract

Variations of snow petrel breeding success in relation to sea-ice extent: detecting local response to large-scale processes?

Olivier

Franeker²,

Creuwels³

et al. 2005

Polar Biol

View full text Add to dashboard Cite

Demographic parameters were estimated for snow petrels Pagodroma nivea nesting at the study colony of Reeve Hill near Casey station, Antarctica between 1984 and 2003. Average breeding success for the colony varied from 18.2% to 76.5%. Breeding effort, hatching and fledging success were subject to a high interannual variability. We examined the influence of regional sea-ice extent on the breeding performance of snow petrels at Reeve Hill. Fewer birds were breeding when sea-ice had been extensive during April-May. Overall breeding success and fledging success were improved during years with extensive sea-ice cover in winter. Successful breeding effort and breeding success were depressed when there was extensive sea-ice cover during January-February. Sea surface temperatures also correlated to snow petrel breeding performance parameters. Previous work showed that large-scale climatic events (ENSO, Antarctic circumpolar wave) and the related sea-ice cover around the Antarctic might affect the lower trophic levels of the marine environment and consequently food availability for snow petrels. A comparison with the long-term study conducted at Ile des Pe´trels (Terre Ade´lie) suggests that despite similarities in the underlying biological processes that control snow petrel breeding performance, the nature of the correlation of large-scale environmental factors with breeding performance differs substantially between the two colonies, probably because of the confounding effects of other environmental factors acting at a local scale (local weather, nest quality), which also affect bird body condition.

show abstract

Dynamics of Antarctic penguin populations in relation to inter-annual variability in sea ice distribution

Cited by 34 publications

References 0 publications

Contrasting population changes in sympatric penguin species in association with climate warming

Contrasting population changes in sympatric penguin species in association with climate warming

Temporal variation in trophic relationships among three congeneric penguin species breeding in sympatry

Variations of snow petrel breeding success in relation to sea-ice extent: detecting local response to large-scale processes?

Contact Info

Product

Resources

About