1. ChrisBenston
ResearchPaper
Geographyof the PolarRegions:Fall 2015
The purpose of thispaper isto gain an understandingof how climate change isaffectingandwill
continue toaffectseabirdphenologyinthe future.Inordertoaccomplishthis,we mustdiscussthe basic
phenologyandthe life historyof birds. Inthispaper,the environmental andabiotic variablesaffecting
the phenologyandthe life historyof birdswill be discussedingreatdetail. Bydiscussingthese variables,
I hope to gain a greaterunderstandingof how the climate isinfluencingthe phenologyof seabirds.
Changesinclimate conditionsaffectthe phenologyof seabirds,itismytheorythatchangesin
phenologyvaryaccordingtolocationandspecies.Inorderto prove or disprove thistheory, Iwill
examine previousstudiesconductedonthissubject.However,since thisisarelativelynew fieldof study
the implicationsof climate change onseabird phenology isstillnotwidelyunderstood.Previous
researchstudieshave identifiedawide varietyof variableswhichmayaffectseabirdphenology.These
variableswill be identifiedanddiscussedingreaterdetail throughoutthispaper.
It has beentheorizedthatdifferentspecies of seabirdsdonotreactin a uniformmatterto
changesinclimaticconditions,due tochangesin the locationandtypesof habitatpreferredbyeach
species. Anothervariable isflyingvsnon-flyingseabirds,the non-flyingseabirdstendtohave a limited
range.This limitedrange of the non-flyingseabirdsaffectstheirphenologybylimitinghow fartheyare
able to travel insearchof food.Additional factors whichmayaffectseabirdphenologyinclude butare
limitedtothe abundance of prey,seaice extentandsea temperature. 1
The decreasedamountsof prey
1 Constable, Andrew J., Jessica Melbourne-Thomas, Stuart P. Corney, Kevin R. Arrigo, Christophe Barbraud, David K. A.
Barnes, Nathaniel L. Bindoff, Philip W. Boyd, Angelika Brandt, Daniel P. Costa, Andrew T. Davidson, Hugh W. Ducklow, Louise
Emmerson, Mitsuo Fukuchi, Julian Gutt, Mark A. Hindell, Eileen E. Hofmann, Graham W. Hosie, Takahiro Iida, Sarah Jacob,
Nadine M. Johnston, So Kawaguchi, Nobuo Kokubun, Philippe Koubbi, Mary-Anne Lea, Azwianewi Makhado, Rob A. Massom,
Klaus Meiners, Michael P. Meredith, Eugene J. Murphy, Stephen Nicol, Keith Reid, Kate Richerson, Martin J. Riddle, Stephen R.
Rintoul, Walker O. Smith, Colin Southwell, Jonathon S. Stark, Michael Sumner, Kerrie M. Swadling, Kunio T. Takahashi, Phil N.

2. servesasa limitingfactorinmanyotherways as well. The lackof prey can delaymigrationandmolting
for seabirds, bothof these activitiesdirectlyinfluence the breedingscheduleof birds. The processof
migrationandmoltingisa veryenergeticallycostlyprocessforbirds,therefore aplentiful foodsupplyis
required.2
For our purposeswe will use methods similartothose describedinthe paperDoesSeaIce
Constrainthe BreedingSchedulesof HighArcticNorthern Fulmars? Inorder to accuratelydetermineif
the changesin climate affectseabirdphenologymonitoringof seabirdsshouldoccurinthe breeding
season.Thismonitoringshouldtake place inall formsof weather,anyvariationinseabirdbehavior
shouldbe observedandnoted. Inorderto collectuniformdatafixed plotswillbe establishedand
markedclearlysotheycan be easilyrelocated. The materialswhichare requiredforthis studyincludes
binocularswithanaperture of 10 by 42 and a spottingscope withanaperture of 60. The distance which
observationsof the breedingbirdsrangesfrom30 to 300 metersaway.Anyobserversshouldgetno
closerthan30 metersinorderto avoid disturbingthe birdswhichare breeding.Inordertoavoid
duplicate countingof the birdsdefining characteristics suchasmolt,plumage andage of the birds
shouldbe recorded.3
The breedingof seabirdsisaffectedbychangesof seaand air temperature.The temperatures
leadstochangesin preyand breedingsites. Asstatedpreviously,bothmoltingandbreedingforseabirds
isveryenergeticallycostly. Asaresult, these activitiestendtooccur whenclimate conditionsare most
suitable andthere isa plentiful foodsource.Inaddition,ithasbeendeterminedthatthe timingof the
Trathan, Dirk C. Welsford, Henri Weimerskirch, KarenJ. Westwood, Barbara C. Wienecke, Dieter Wolf-Gladrow, SimonW. Wright,
Jose C. Xavier, and Philippe Ziegler. "Climate Change andSouthern OceanEcosystems I: How Changes in Physical Habitats Directly
Affect Marine Biota." Glob Change Biol Global Change Biology 20.10 (2014): 3004-025. Web. 10 Oct. 2015
2 Chambers, Lynda E., Peter Dann, Belinda Cannell, andEric J. Woehler. “Climate as a Driver of Phenological Change in Southern
Seabirds." Int J Biometeorol International Journal of Biometeorology 58.4 (2013): 603-12. October, 5, 2015.
3 Mallory, Mark L., and MarkR. Forbes. "Does Sea Ice Constrain The Breeding Schedules Of HighArctic Northern Fulmars?" The
Condor Condor 109.4 (2007): 894. October 5, 2015.

3. breedingitself mayinfluence seabirdpopulations. The moltingpatternsof birdsare influencedby
breedingandalsohave abilitytoinfluence whenbreedingoccurs. Anydeviationfromnormal migration
patterns, moltingorbreedingitself maycause anasynchronybetweenthe differentspecies.Thismay
leadto changesinthe trophiclevels,suchaspredatorandprey relationships.2
By examiningthe earlierdatasetsand comparingthe laterdata sets,a trendwasobserved.
While comparingthe earlydatasetsvs the laterdata sets,the laterdata setsshowedaslightchange in
the phenologyof seabirds.The trendobservedinthe laterdatasets showedaslighttendencytobreed
earlier. However,the phenologyof certainspeciesof seabirdshadnoobservational change.A potential
explanationforthiscouldbe differences whichwere notedamongthe phenologyof seabirdsaccording
to theirlocationandtheirtaxonomicfamilies. 2
The dietoptionsof seabirdsisa largerreflection,of where the seabirds are foraging. These
variablescanbe influencedchangesinthe environment,thisleadsto changesin the typesandamounts
of preyavailable.2
The availabilityof the foodhasshownto affectthe growthratesof chicksand the
adultseabirds.In addition, the breedingperformanceisdirectlytiedtothe availability of preysources.
Anydecrease inthe amountof prey mayleadto reducedbreedingperformance amongthe seabirds.
The resultsof thisstudyshowedthe foragingactivitiesvaryinresponse tothe changingenvironmental
conditions.The populationof seabirdsisdirectlyinfluencedbyseveral variableswhichare mostlymade
of differentabioticcomponents.These abioticcomponents include the seaice extentandthe air
2 Chambers, Lynda E., Peter Dann, Belinda Cannell, and Eric J. Woehler. “Climate as a Driver of Phenological Change in Southern
Seabirds." Int J Biometeorol International Journal of Biometeorology 58.4 (2013): 603-12. October, 5, 2015.
2 Chambers, Lynda E., Peter Dann, Belinda Cannell, and Eric J. Woehler. “Climate as a Driver of Phenological Change inSouthern
Seabirds." Int J Biometeorol International Journal of Biometeorology 58.4 (2013): 603-12. October, 5, 2015.

4. temperature (alsocalledSST).7
Inaddition, changesof seabirdphenologymayaffectseabirdsbyputting
themout syncof withtheirprey. 5
By studyingpopulations of the EmperorPenguinsandSnow Petrels,the conclusioncanbe
drawnthat differentspeciesof seabirdsresponddifferentlytochangesinthe climate conditions.When
the air temperature increasedduringthe autumnandthe wintermonths,the survivalratesof the
EmperorPenguinincreased.The numberof successfulbreedingpairsforthe Snow Petrelswill decrease
if the air temperature declinesduringthe spring.The populationof Snow Petrelswillincreasebasedon
the amountof seaice and air temperature.If the airtemperature increasesduringthe spring,the
breedingpopulation of the EmperorPenguinswill decrease inresponse tochangesinclimate
conditions.Thisdecrease inthe breedingpopulationof the EmperorPenguinscanalsobe tiedto
declinesinthe SouthernOscillationIndex. 6
Thisvariationamonglocationandspeciesof birdsiscalledphenotype plasticity.Phenotype
plasticitycanbe definedaswhendifferentphenotypeswiththe same type of genotypereactdifferently
basedon the environment. Anothervariablewhichinfluencesthe phenologyof seabirds, istheir
lifespan.This meansbirdswithalongerlifespantendnottobreedwhenthe environmentalconditions
are lessthanideal.Andbirdswithashorterlife spantendtobreedevenif the environmentalconditions
are lessthanideal. Inaddition,the fecundityrate of the seabirdsinfluenceconditionsinwhichbreeding
occurs, those withlowerfecundityratestendtobreedlessfrequentlyinpoorenvironmental conditions.
These birdsthattendto have smallerclutchsizesandtendto have veryfew eggsduringthe breeding
season. However, birdswithahigherrate of fecunditytendtohave largerclutchsizesandproduce
7
Jenouvrier, S., H. Weimerskirch, C. Barbraud, Y.-H. Park, and B. Cazelles. "Evidence of a Shift in the Cyclicity of
Antarctic Seabird Dynamics Linked to Climate." Proceedings of the Royal Society B: Biological Sciences 272.1566
(2005): 887-95. October 5, 2015.
6 Jenouvrier, Stephanie, Christophe Barbraud, and Henri Weimerskirch. "Long-Term Contrasted Responses To
Climate Of Two Antarctic Seabird Species." Ecology 86.11 (2005):2889-903.October, 5, 2015.

5. manyeggs peryear.A trendwas observedwherelongerlived speciestendednottobreedand
abandonedtheirnestsinpoorbreeding conditions,inordertofocuson survival.However,shorterlived
speciesbreedduringpoorconditionsinanattempttohave a successful clutch.5
The data showedextreme variationamongthe phenologyseabirdsandhow eachindividual
speciesrespondstochangesinthe environment. Someof the speciesof seabirdswere observed
breedingearlierandsome were observedbreedinglater.However,withsome speciesof seabirdsno
observational change inthe breedingwasnoted.Some of the variationinbreedinghabitatscanbe
linkedtochangesinthe locationsand the familiesof the seabirds.The resultsforseabirdsinlivingthe
Antarcticshowedthe changesinphenologywerealmostequal withsevenspeciesbreedingearlierand
six speciesbreedinglater. The specieswhichwere breedinglaterare:The Adelie Penguin,Southern
Fulmar,AntarcticPetrel,Cape Petrel,Snow Petrel,andthe SouthPolarSkua.The Specieswhichare
breedingearlierincludesthe Royal Penguin,Little Penguin,GentooPenguin,ChinstrapPenguin,
PygoscelidPenguins,SouthPolarSkuaandthe AfricanPenguin.4
The data showsa sighttrendtowardsseabirdbreedingearlierinresponsetochangesin the
climate. However,the changesobservedinseabirdphenologyare dependentonnumerousvariables
and can vary accordingto the locationand the species. DuringmyresearchIfound data showingthat
twoseparate populationsof the SouthPolar SkuaandAdelie Penguinsbothbreedingearlierandlater
basedon theirlocation.Thisprovidesastrongargumentthat locationgreatlyinfluencesthe breeding
phenologyof seabirds.Inaddition,the observedchangesinseabirdphenologywere foundtovary
amongdifferentspecieswithinthe same location.Inthiscase the changesof seabirdphenologycanbe
tiedto changesinthe environmental variableswithinthe areasurroundingthe breedinghabitats. The
5 Grémillet, David, and Anne Charmantier. "Shifts in Phenotypic Plasticity Constrain the Value of Seabirds as
Ecological Indicators of Marine Ecosystems." Ecological Applications 20.6 (2010):1498-503. October 5, 2015.
4 Chambers, Lynda E., Peter Dann, Belinda Cannell, and Eric J. Woehler. “Climate as a Driver of Phenological Change inSouthern
Seabirds." Int J Biometeorol International Journal of Biometeorology 58.4 (2013): 603-12. October, 5, 2015

6. data, whichIexaminedshowedvariationamongtwo differentspecieswithinthe same location,based
on the changingof the climate conditions. The studyof examinedbreedingdataof the Snow Petrelsand
the EmperorPenguins which varied accordingtochangesin the environmentalvariables (seecharts1A
and 1B formore information).7
The datapresentedinthe chartsshowed breedingsuccessandthe
numbersof breedingpairsof the EmperorPenguinsisdirectlytiedtothe seaice concentration. As
determinedbythe analyzingthe datadecreased levelsof seaice concentration leadstodecreased
numbersof breedingpairs anddecreased levelsof breedingsuccess.In addition, decreasedair
temperatures inspringleadstochangesinthe phenology of EmperorPenguins. The decreasedair
temperature leadstodecreasednumbersof EmperorPenguinsbreedingforthe firsttime,the number
of breedingpairs, andthe numberof EmperorPenguinssurvivingatseaduringthe firstyear, and the
breedingsuccessandthe proportionof breedersfor the EmperorPenguins. However,the variables
affectingbreedingpopulationsof the Snow Petrelsvariesfromthe variablesaffecting the breeding
populationsof the EmperorPenguins. Decreasesinthe Snow Petrel populationwasobservedwhenthe
seaice extentdecreased.The decreasedlevelsof the seaice extentwere tiedtodecreasedlevelsof
breedingsuccess,decreasedlevelsof breedingpairs,anddecreasednumbersof Snow Petrelssurviving
at sea duringthe first year.Inaddition,Iobserveda downwardtrendinthe proportionof breedersand
the proportionof birdsattemptingtobreedforthe firsttime.If changesin the air temperature orthe
southernoscillationindex occurs,aslighttomoderate decrease canbe observedinfollowing.The
breedingsuccessof The SnowPetrelswill decrease,proportionof breedersandthe proportionof birds
breedingwilldecreaseaswell.However,these variablestendtovarynotonlyaccordingto speciesand
location,butalsoare influencedbythe seasonsandtendtovaryfrom yearto year.Since the numberof

7. birdspeciesbreedingearlierisalmostequal tothe numberof birdspecies breedinglater,nosignificant
conclusionsnodrawnfromthisdata. 6
Chart 1- A
6
6 Jenouvrier, Stephanie, ChristopheBarbraud, andHenri Weimerskirch. "Long-TermContrasted
ResponsesTo Climate Of Two Antarctic Seabird Species." Ecology 86.11 (2005):2889-903.October, 5,
2015.
-0.8
-0.6
-0.4
-0.2
0
0.2
0.4
0.6
0.8
1
The breeding of Emperior Penguins and The Associated Environmental
Variables
Emperor Penguin So ( Survival during the first
year at sea)
Emperor Penguin BS (Breeding Success)
Emperor Penguin N(number of breeding
pairs)
Emperor Penguin Pb( Proportion of
breeders)
Emperor Penguin Pb+6 (Proportion of birds
attempting to bird for first time)

8. Chart 1-B 6
6
6 Jenouvrier, Stephanie, ChristopheBarbraud, andHenri Weimerskirch. "Long-TermContrasted
ResponsesTo Climate Of Two Antarctic Seabird Species." Ecology 86.11 (2005):2889-903.October, 5,
2015.
6 Jenouvrier, Stephanie, ChristopheBarbraud, andHenri Weimerskirch. "Long-TermContrasted
ResponsesTo Climate Of Two Antarctic Seabird Species." Ecology 86.11 (2005):2889-903.October, 5,
2015.
-1
-0.8
-0.6
-0.4
-0.2
0
0.2
0.4
0.6
0.8
1
The Breeding of Snow Petrels and The Associated Environmental Variables
Snow Petrel So ( Survival during the first year at sea)
Snow Petrel BS (Breeding Success)
Snow Petrel N(number of breeding pairs)
Snow Petrel Pb( Proportion of breeders)
Snow Petrel Pb+6 (Proportion of birds attempting to bird for first time)

9. Basedon the data we conclude thatthe effects of climate andseabirdphenologyisnotwidely
understood.Thisisavery complex subject withmanyvariablesinvolved.Since the datashowsAntarctic
seabirdsare almostequal uponcomparison if theybreedearlierorlater. The datashowsa slighttrend
inwhichAntarcticseabirdsbreed earlier.However,Iwasunable tocome to any real significant
conclusionsonhowseabirdphenologyischanginginresponsetothe changingclimate.Inordercome to
any concrete conclusionsmore researchisrequired,especiallyconsideringthe everchangingclimate.
Bibliography
Grémillet,David,andAnne Charmantier."ShiftsinPhenotypicPlasticityConstrainthe Value of Seabirds
as Ecological Indicatorsof Marine Ecosystems." EcologicalApplications 20.6 (2010): 1498-503. October
5, 2015.
Jenouvrier,S.,H.Weimerskirch,C.Barbraud,Y.-H.Park,and B. Cazelles."Evidence of aShiftinthe
Cyclicityof AntarcticSeabirdDynamicsLinkedtoClimate." Proceedingsof theRoyalSociety B: Biological
Sciences 272.1566 (2005): 887-95. October5, 2015.
Chambers,LyndaE., PeterDann,BelindaCannell,andEricJ.Woehler. “Climate asaDriverof
Phenological Change inSouthernSeabirds." IntJBiometeorolInternationalJournalof Biometeorology
58.4 (2013): 603-12. October,5, 2015.
Jenouvrier,Stephanie,Christophe Barbraud,andHenri Weimerskirch."Long-TermContrasted
ResponsesToClimate Of TwoAntarcticSeabirdSpecies." Ecology 86.11 (2005): 2889-903. Web.5 Oct.
2015.
Croxall,J.P.,P.N. Trathan,and E. J. Murphy. "EnvironmentalChange andAntarcticSeabird
Populations."Science297.5586 (2002): 1510-514. October5, 2015.
Barbraud,C., and H. Weimerskirch."AntarcticBirdsBreedLaterinResponse toClimate Change."
Proceedingsof theNationalAcademy of Sciences 103.16 (2006): 6248-251. October,5, 2015.

10. Mallory,Mark L., and Mark R. Forbes."DoesSeaIce ConstrainThe BreedingSchedulesOf HighArctic
NorthernFulmars?" TheCondorCondor109.4 (2007): 894. October5, 2015.
Constable,AndrewJ.,JessicaMelbourne-Thomas,StuartP.Corney,KevinR.Arrigo,Christophe
Barbraud,DavidK. A. Barnes,Nathaniel L.Bindoff,PhilipW.Boyd,AngelikaBrandt,Daniel P.Costa,
AndrewT.Davidson,HughW. Ducklow,Louise Emmerson,MitsuoFukuchi,JulianGutt,Mark A.Hindell,
EileenE.Hofmann,GrahamW. Hosie,TakahiroIida,Sarah Jacob,Nadine M.Johnston,SoKawaguchi,
NobuoKokubun,Philippe Koubbi,Mary-AnneLea,Azwianewi Makhado,RobA.Massom, KlausMeiners,
Michael P. Meredith,Eugene J.Murphy,StephenNicol,KeithReid,Kate Richerson,MartinJ.Riddle,
StephenR.Rintoul,WalkerO.Smith,ColinSouthwell,JonathonS.Stark,Michael Sumner,KerrieM.
Swadling,KunioT.Takahashi,Phil N.Trathan,DirkC.Welsford,Henri Weimerskirch,KarenJ.Westwood,
Barbara C. Wienecke,DieterWolf-Gladrow,SimonW.Wright,Jose C.Xavier,andPhilippe Ziegler.
"Climate Change andSouthernOceanEcosystemsI:How ChangesinPhysical HabitatsDirectlyAffect
Marine Biota."Glob ChangeBiol Global ChangeBiology 20.10 (2014): 3004-025. October,10, 2015.