BBC Wildlife - UK (2020-09)

Skua: Graeme

Snow/A

amy;

Ha

fMoon

sand

&

ceberg:

Abb

eTray

er-Sm

th/Greenpeace;

eephant

seal: Otto P

antema/M

nden/FLPA; nest

ng:

Peter

Barr

tt/Alamy

Chinstraps,unliketheice-loving
emperorsandAdélies,arebuiltfora life
atsea,spendingninemonthsoftheyear
fishingintheopenocean.Theyareagile
swimmers,abletodiveto100mand
ventureupto30kmoffshore.Butwhen
thebreedingseasonrollsin,theytransform
intosturdymonochromemountaineers.
Wewatchthemwaddle,hopandjump
intwosandthreesfromtheirrookeries
atthesummitoftall,exposedcliff-faces,
down‘penguinhighways’tothefrigid
watersbelow,wheretheyfeastonkrillto
laterregurgitatetotheirraucouschicks.
“Chinstrapsaretough– theycanhandle
a realpummelling,”saysteam
leaderSteveForrest,a
veteranbiologistwith
morethan 25 Antarctic
seasonsunderhisbelt.
Whenit comestobreeding,
chinstrapshavea classicco-parenting
arrangement.Typically,themalebuildsa
freshcircularnestfrompebbles,and,once
theeggshavehatched,theparentstakeit
inturnstohuntandmindthechicks.They
returntothesamenestsiteeachyearto
breed,whichmakesthemmonogamous
by default. “It’s more a case of shared

realestate,”saysSteve.“They’veessentially

boughta housetogether,whichtheyreturn

toyearafteryear– so,inalllikelihood,

they’llendupwiththesamemate.”After

severalweeks,thechicksarelargeenough

toentera crèche,huddlingwithother

youngsterswhiletheparents hunt for food.

Tr a c k i n ga n dt a l l y i n g

Tosurveythebreedingpopulation,the

scientistscountthenests,notthebirds

themselves.Thetaskis easierwhenfamily

groupsarestilltogether,sotimingis key.

The chicksarejusta fewweeksoldwhenwe

arriveandonlyslightlysmaller

than their parents, who average

just70cminheight.Butwhatchinstraps

lackinsize,theymakeupforinaggression.

“Theyarefiercebirds,”saysSteve.“They’ll

fightoveranything...a pebble,a spaceor

accesstoa penguinhighway.”

Countingpenguinnestssoundsserene,

almostmeditative,butcomeswithincredible

challenges.A day’sworkusuallyseesthe

scientistsnegotiatinga trickylandingby

Zodiac,oftenonanexposed,windswept

shore,then– owingtothebirds’penchant

forhighandremotenestsites– scalingsheer

cliffs,allthewhilekeepingtheirdistance,

soasnottostressthebirds.Tocomplicate

mattersfurther,thepenguinstendtocluster

together,obscuringtheirstonyabodes.

“Itis themostfocused,exhaustingand

exhilaratingthingyoucandooutdoors,”says

Steve.“Youhavetoholdstatuesqueposes,

balancedononetoeona slopegreasedwith

guano. You have to ignore the wind, the

Clockwisefrom

above:thedramatic

landscapeofHalf

MoonIslandinthe

SouthShetlands;

gentoopenguinsfish

from an iceberg; a

southernelephant

sealisanunwelcome

visitoramongnesting

chinstraps;creatinga

nestfromstones– the

arrangementneeds to

be just so.

62 BBC Wildlife September 2020

Skuastryto

takeyoung

penguinsand

often succeed.