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First recorded loss of an emperor penguin colony in the recent period of Antarctic regional warming: implications for other colonies.

Trathan PN, Fretwell PT, Stonehouse B - PLoS ONE (2011)

Bottom Line: These studies suggest that continued climate change is likely to impact upon future breeding success and colony viability for this species.Furthermore, a recent circumpolar study by Fretwell & Trathan (2009) highlighted those Antarctic coastal regions where colonies appear most vulnerable to such changes.The implications of this are important for future modelling work and for understanding which colonies actually are most vulnerable.

View Article: PubMed Central - PubMed

Affiliation: British Antarctic Survey, Cambridge, United Kingdom. p.trathan@bas.ac.uk

ABSTRACT
In 1948, a small colony of emperor penguins Aptenodytes forsteri was discovered breeding on Emperor Island (67° 51' 52″ S, 68° 42' 20″ W), in the Dion Islands, close to the West Antarctic Peninsula (Stonehouse 1952). When discovered, the colony comprised approximately 150 breeding pairs; these numbers were maintained until 1970, after which time the colony showed a continuous decline. By 1999 there were fewer than 20 pairs, and in 2009 high-resolution aerial photography revealed no remaining trace of the colony. Here we relate the decline and loss of the Emperor Island colony to a well-documented rise in local mean annual air temperature and coincident decline in seasonal sea ice duration. The loss of this colony provides empirical support for recent studies (Barbraud & Weimerskirch 2001; Jenouvrier et al 2005, 2009; Ainley et al 2010; Barber-Meyer et al 2005) that have highlighted the vulnerability of emperor penguins to changes in sea ice duration and distribution. These studies suggest that continued climate change is likely to impact upon future breeding success and colony viability for this species. Furthermore, a recent circumpolar study by Fretwell & Trathan (2009) highlighted those Antarctic coastal regions where colonies appear most vulnerable to such changes. Here we examine which other colonies might be at risk, discussing various ecological factors, some previously unexplored, that may also contribute to future declines. The implications of this are important for future modelling work and for understanding which colonies actually are most vulnerable.

Show MeSH
The spatial pattern of trend in sea ice duration change over 1979–2004 [13].Scale shows trend in days per year. Black squares indicate the location of all known emperor penguin colonies [8]. Colony reference numbers refer to Table 2.
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pone-0014738-g005: The spatial pattern of trend in sea ice duration change over 1979–2004 [13].Scale shows trend in days per year. Black squares indicate the location of all known emperor penguin colonies [8]. Colony reference numbers refer to Table 2.

Mentions: The link between fast ice and pack ice is complex and detailed relationships depend upon local circumstances; however, in most situations fast ice only forms in stable conditions, with surface currents, ocean swell and wind action potentially impeding fast ice development. Therefore, changes in fast ice production would be expected to occur if altered pack ice extent and duration meant locations were subject to increased wave action. No large-scale historical datasets exist for fast ice extent or duration, though remotely sensed data do exist for seasonal sea ice. The emperor penguin breeding locations (Figure 5) of all known colonies [8] can be overlaid onto recently published sea ice duration maps [13] to examine their vulnerability. Tabulation (Table 2) of sea ice duration [13] indicates those colonies that may be currently more vulnerable to climate change effects. The colony at Emperor Island is where sea ice trends are most negative. However, the colony is not the most northerly emperor penguin breeding site, there being 9 others that occur at lower latitudes. Similarly, colony locations where sea ice trends are most positive are not the most southerly, there being a number that are further south; it is notable that those colonies where sea ice trend is most positive all occur in the Ross Sea.


First recorded loss of an emperor penguin colony in the recent period of Antarctic regional warming: implications for other colonies.

Trathan PN, Fretwell PT, Stonehouse B - PLoS ONE (2011)

The spatial pattern of trend in sea ice duration change over 1979–2004 [13].Scale shows trend in days per year. Black squares indicate the location of all known emperor penguin colonies [8]. Colony reference numbers refer to Table 2.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3046112&req=5

pone-0014738-g005: The spatial pattern of trend in sea ice duration change over 1979–2004 [13].Scale shows trend in days per year. Black squares indicate the location of all known emperor penguin colonies [8]. Colony reference numbers refer to Table 2.
Mentions: The link between fast ice and pack ice is complex and detailed relationships depend upon local circumstances; however, in most situations fast ice only forms in stable conditions, with surface currents, ocean swell and wind action potentially impeding fast ice development. Therefore, changes in fast ice production would be expected to occur if altered pack ice extent and duration meant locations were subject to increased wave action. No large-scale historical datasets exist for fast ice extent or duration, though remotely sensed data do exist for seasonal sea ice. The emperor penguin breeding locations (Figure 5) of all known colonies [8] can be overlaid onto recently published sea ice duration maps [13] to examine their vulnerability. Tabulation (Table 2) of sea ice duration [13] indicates those colonies that may be currently more vulnerable to climate change effects. The colony at Emperor Island is where sea ice trends are most negative. However, the colony is not the most northerly emperor penguin breeding site, there being 9 others that occur at lower latitudes. Similarly, colony locations where sea ice trends are most positive are not the most southerly, there being a number that are further south; it is notable that those colonies where sea ice trend is most positive all occur in the Ross Sea.

Bottom Line: These studies suggest that continued climate change is likely to impact upon future breeding success and colony viability for this species.Furthermore, a recent circumpolar study by Fretwell & Trathan (2009) highlighted those Antarctic coastal regions where colonies appear most vulnerable to such changes.The implications of this are important for future modelling work and for understanding which colonies actually are most vulnerable.

View Article: PubMed Central - PubMed

Affiliation: British Antarctic Survey, Cambridge, United Kingdom. p.trathan@bas.ac.uk

ABSTRACT
In 1948, a small colony of emperor penguins Aptenodytes forsteri was discovered breeding on Emperor Island (67° 51' 52″ S, 68° 42' 20″ W), in the Dion Islands, close to the West Antarctic Peninsula (Stonehouse 1952). When discovered, the colony comprised approximately 150 breeding pairs; these numbers were maintained until 1970, after which time the colony showed a continuous decline. By 1999 there were fewer than 20 pairs, and in 2009 high-resolution aerial photography revealed no remaining trace of the colony. Here we relate the decline and loss of the Emperor Island colony to a well-documented rise in local mean annual air temperature and coincident decline in seasonal sea ice duration. The loss of this colony provides empirical support for recent studies (Barbraud & Weimerskirch 2001; Jenouvrier et al 2005, 2009; Ainley et al 2010; Barber-Meyer et al 2005) that have highlighted the vulnerability of emperor penguins to changes in sea ice duration and distribution. These studies suggest that continued climate change is likely to impact upon future breeding success and colony viability for this species. Furthermore, a recent circumpolar study by Fretwell & Trathan (2009) highlighted those Antarctic coastal regions where colonies appear most vulnerable to such changes. Here we examine which other colonies might be at risk, discussing various ecological factors, some previously unexplored, that may also contribute to future declines. The implications of this are important for future modelling work and for understanding which colonies actually are most vulnerable.

Show MeSH