Welcome

First-​of-​its-​kind study led by the Uni­ver­sity of Min­nesota pro­vides impor­tant infor­ma­tion on the impact of envi­ron­men­tal change

Adélie pen­guins (Pygoscelis adeliae) may actu­ally ben­e­fit from warmer global tem­per­a­tures, the oppo­site of other polar species, accord­ing to a break­through study by an inter­na­tional team led by Uni­ver­sity of Min­nesota Polar Geospa­tial Cen­ter researchers. The study pro­vides key infor­ma­tion affirm­ing hypo­thet­i­cal pro­jec­tions about the con­tin­u­ing impact of envi­ron­men­tal change.

Researchers from the United States and New Zealand used a mix of old and new tech­nol­ogy study­ing a com­bi­na­tion of aer­ial pho­tog­ra­phy begin­ning in 1958 and mod­ern satel­lite imagery from the 2000s. They found that the pop­u­la­tion size of an Adélie pen­guin colony on Antarctica’s Beau­fort Island near the south­ern Ross Sea increased 84 per­cent (from 35,000 breed­ing pairs to 64,000 breed­ing pairs) as the ice fields retreated between 1958 – 2010, with the biggest change in the last three decades. The aver­age sum­mer tem­per­a­ture in that area increased about a half a degree Cel­sius per decade since the mid-​1980s.

Michelle LaRue, co-​author, Polar Geospa­tial Cen­ter, Uni­ver­sity of Minnesota’s Col­lege of Sci­ence and Engi­neer­ing »

The first-​of-​its-​kind study was pub­lished April 3 in PLOS ONE, a lead­ing peer-​reviewed sci­en­tific jour­nal. The research affirms mod­els pub­lished in 2010 pro­ject­ing how south polar pen­guins will respond to changed habi­tat as Earth’s atmos­phere reaches 2 degrees Cel­sius above pre-​industrial lev­els, a point that is rapidly approach­ing.

The study showed that avail­able habi­tat for Adélie pen­guins on the main por­tion of the Beau­fort colony, on the south coast, increased 71 per­cent since 1958, with a 20 per­cent increase from 1983 – 2010. The extent of the snow and ice field to the north of the main colony did not change from 1958 – 1983, but then retreated 543 meters from 1983 – 2010.

In addi­tion to the over­all pop­u­la­tion growth, researchers saw an increase in pop­u­la­tion den­sity within the colony as it filled in what used to be unsuit­able habi­tat cov­ered in snow and ice. They also found that the emi­gra­tion rates of birds banded as chicks on Beau­fort Island to colonies on nearby Ross Island decreased after 2005 as avail­able habi­tat on Beau­fort increased, lead­ing to altered dynam­ics of the pop­u­la­tion stud­ied.

“This research raises new ques­tions about how Antarc­tic species are impacted by a chang­ing envi­ron­ment,” said Michelle LaRue, the paper’s co-​author and research fel­low at the Polar Geospa­tial Cen­ter in the Uni­ver­sity of Minnesota’s Col­lege of Sci­ence and Engi­neer­ing. “This paper encour­ages all of us to take a sec­ond look at what we’re see­ing and find out if this type of habi­tat expan­sion is hap­pen­ing else­where to other pop­u­la­tions of Adélie pen­guins or other species.”

World-​renowned pen­guin expert and study co-​author David Ain­ley, a lead author of an ear­lier study, agreed that this study gives researchers impor­tant new infor­ma­tion. “We learned in pre­vi­ous research from 2001 – 2005 that it is a myth that pen­guins never move to a new colony in large num­bers. When con­di­tions are tough, they do,” said Ain­ley, a senior marine wildlife ecol­o­gist with H.T. Har­vey and Asso­ciates, an envi­ron­men­tal con­sult­ing com­pany in Cal­i­for­nia. “This study at Beau­fort and Ross Islands pro­vides empir­i­cal evi­dence about how this pen­guin attribute will con­tribute to their response to cli­mate change.”

footage :

(Video credit PolarTREC-​programme)

Adélie pen­guins are com­mon along the south­ern Antarc­tic coast. They are smaller than their Emperor pen­guin coun­ter­parts stand­ing about 46 to 75 cm when upright and weigh­ing about 4.5−5.4 kg. The Adélie pen­guin lives only where there is sea ice but needs the ice-​free land to breed. Breed­ing pairs pro­duce on aver­age one chick per year and return to the same area to breed if con­di­tions haven’t changed.

To deter­mine changes in avail­able nest­ing habi­tat in this study, researchers gath­ered aer­ial pho­tos dur­ing the pen­guin incu­ba­tion period in 1958, 1983 and 1993 and high-​resolution satel­lite images from 2005 and 2010. Researchers over­laid the images exactly, lin­ing up rocks and other geo­graph­i­cal land­marks. They stud­ied guano (pen­guin feces and urine) stains to deter­mine the avail­able habi­tat.

In the future, researchers plan to use addi­tional satel­lite imagery to look at other Adélie pen­guin pop­u­la­tions to help under­stand the dynam­ics and envi­ron­men­tal fac­tors that influ­ence regional pop­u­la­tions. The Adélie pen­guin is con­sid­ered Near Threat­ened accord­ing the IUCN Red List of Threat­ened Species™.

“This study brought together researchers from dif­fer­ent aca­d­e­mic dis­ci­plines who all con­tributed their exper­tise,” LaRue said. “We had peo­ple who study cli­mate change, spa­tial analy­sis, and wildlife pop­u­la­tion dynam­ics. This is how good sci­ence leads to results.”


(Source: UMNews news release, 03.04.2013)