TextWinter Geographic Patterns of American and Fish CrowsAre winter sightings of Fish and American crows centered on major urban developments or in natural habitats such as state parks?

Emilie R. LuttmanShippe nsburg U nive rsityCapstone GIS Proje ctFall 2016

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Erie

HarrisburgPittsburgh

Philadelphia

Williamsport

State College

Bald Eagle

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Erie

HarrisburgPittsburgh

Philadelphia

Williamsport

State College

Bald Eagle

PurposePre vious re se arch has shown thatcrow spe cie s te nd to cong re g atearound human se ttle me nts.Howe ve r, little is known aboutthe ir winte r g e og raphicmove me nts. One hypothe sis hassug g e ste d that the se spe cie s mayce nte r the ir g e og raphicmove me nts on site s such asurban are as, whe re humande rive d food re source s are moreabundant. This proje ct focuse d onthe sig hting s of two spe cie s ofcrows in the state ofPe nnsylvania: the Ame rican Crow(Corvus brachyrhynchos) and theFish Crow (Corvus ossifrag us). Theproje ct atte mpte d to se e if the se

spe cie s take advantag e of morede nse ly populate d are as ve rsusnatural habitat.Objectives:•Download Pe nnsylvania spe cie ssig hting s of both Fish and Ame ricancrows from be twe e n Nove mbe r2011 throug h March 2016 from theCorne ll Lab of Ornitholog y’s E-birdbasic datase t.•Download the polyg on data se tssuch as state park boundarie s, majorurban are as, and the Pe nnsylvaniaState Boundary from thePe nnsylvania Spatial Data Acce sswe bsite .•Sort the sig hting data using se le ct

by attribute s to only includewinte r months (Nove mbe rthroug h March)•U se a ‘Point De nsity’ g e o-proce ssing tool with a 2 kilome te rce ll size to map whe re thesig hting s of both spe cie s arece nte re d on.•U se the ‘Ide ntity’ tool tode te rmine the numbe r ofsig hting s of both spe cie s thatoccur in e ithe r habitat, as we ll asthe numbe r of sig hting s of thoseat occur in ne ithe r.

MethodsFirst, a file g e odatabase was cre ate d to hold all of thedata use d in this analysis sig hting data of bothAme rican and Fish crows we re downloade d from theEbird public datase t. This data was customize d to onlyinclude the sig hting s of the se spe cie s in the state ofPe nnsylvania that occurre d be twe e n Nove mbe r of2011 and March of 2016. Ne x t, data containing thePe nnsylvania state boundary, urban are as, and stateparks we re also downloade d. Data displaying thetowns and citie s of the state we re downloade d as we llfor late r cartog raphic use s. All of the data wasproje cte d in the Pe nnsylvania State Plane NorthProje ction.The crow sig hting data was conve rte d from its orig inalte x t file into a CSV file . The n the data was e x porte dinto the g e odatabase as fe ature classe s. Ne x t, se le ct byattribute s was use d to se le ct for winte r months(Nove mbe r throug h March). The re sulting

fe ature classe s the n containe d the winte r sig hting s ofboth spe cie s in the state . This data was the n loade donto ArcMap for g e oproce ssing .The e nvironme nts we re the n se t prior to any analysis.First, the proce ssing e x te nt was se t to the same laye ras the Pe nnsylvania state boundary. The n the maskunde r raste r proce ssing was also se t to the stateboundary. The ce ll size use for all analyse s was 2Kilome te rs. The first tool use d was the ‘Point De nsity’tool that displaye d re g ions of the state whe re the rewe re hig he r conce ntrations of sig hting s for e achspe cie s (Fig ure 2, 3).

The se cond tool that was use d was the ‘Ide ntity’ toolthat is de sig ne d to ide ntify be twe e n a point andpolyg on laye r whe re the y may ove rlap. This tool wasthe n use d to ide ntify the numbe r of sig hting s forboth spe cie s that occurre d inside of the urban are asin the ne w laye r's attribute table . The n the se laye rswe re furthe r analyze d with the same tool to producelaye rs with attribute table s containing data withinboth urban are as and state parks. Se le ct by attribute swas the n use d to de te rmine the numbe r of sig hting sthat occurre d both within and outside of both habitattype s for both spe cie s (Table 1) (Fig ure 4).

Figure 2: Point density ofthe sightings of AmericanCrows in the urban areasand state parks of the stateof Pennsylvania

Figure 3: Point density ofthe sightings ofFish Crowsin the urban areas and stateparks of the state ofPennsylvania

Figure 4: Percentage of sightings in and out ofboth urban areas and state parks between both

Table 1: Percentage of sightings inand out of both urban areas andstate parks, as well as those thatonly occur in one or the other.

Data SourcesEbird. 2016. Custom American Crow Sightings November 2011-March2016 in Pennsylvania. Ebird. Last accessed online on October 13, 2016at http://ebird.org/ebird/data/downloadEbird. 2016. Custom Fish Crow Sightings November 2011-March 2016 inPennsylvania. Ebird. Last accessed online on October 13, 2016 athttp://ebird.org/ebird/data/downloadPennsylvania Department of Conservation and Natural Resources.2016. Common Birds of Bald Eagle State Park. Bald Eagle State Park .Last accessed online Nov 17, 2016 athttp://www.dcnr.state.pa.us/stateparks/findapark/baldeagle/Pennsylvania Department of Conservation and Natural Resources.2015. State Park Boundaries. Pennsylvania Spatial Data Access. Lastaccessed online on October 13, 2016 athttp://www.pasda.psu.edu/uci/DataSummary.aspx?dataset=114

Pennsylvania Department of Transportation. 2016. PennsylvaniaState Boundary. Pennsylvania Spatial Data Access. Last accessedonline on October 13, 2016 athttp://www.pasda.psu.edu/uci/DataSummary.aspx?dataset=42Pennsylvania Department of Transportation. 2016. PennsylvaniaUrban Area Boundary. Pennsylvania Spatial Data Access. Lastaccessed online on October 13, 2016 athttp://www.pasda.psu.edu/uci/DataSummary.aspx?dataset=26U.S. Geologic Survey. 2014. Cities and Towns of the United States.Data.gov. Last accessed online on October 13, 2016 athttps://catalog.data.gov/dataset/cities-and-towns-of-the-united-states-direct-download

Fish Crow (Corvus ossifragus) American Crow (Corvus brachyrhynchos)

Results:

Summary and Conclusion:According to Fig ure s 1 and 2, both spe cie s of crowste nde d to ce nte r the ir winte r g e og raphic move me ntsin urban are as. The se are as include d the cite s ofPhilade lphia, Williamsport, State Colle g e , Pittsburg h,and Erie . The one e x ce ption to this patte rn was in thecluste rs of sig hting s around one particular are a: BaldEag le State Park. This are a is locate d just we st ofWilliamsport, and it provide s a wide varie ty of naturalhabitats for bird spe cie s. The irony of the se finding s isthat in the official lite rature publishe d by Bald Eag leState Park, the Ame rican crow is liste d as a commonspe cie s, but the Fish crow is not. Like ly this is due tothe Fish crow not be ing as we ll-known as its morecharasmatic e volutionary cousin, and so it was notinclude d.Furthe rmore , accounting for all of the sig hting s, it wasfound that a hig he r pe rce ntag e of Fish crow sig hting soccurre d in state parks rathe r than in urban are as, and

a hig he r pe rce ntag e of Ame rican crow sig hting soccurre d in urban are as ove r state parks (Fig ure 3).Howe ve r, whe n accounting for sig hting s that occurre doutside of both habitats, an ove rwhe lming pe rce ntag eof sig hting s for both spe cie s occurre d in urbane nvironme nts ove r natural state parks.The initial que stion of this proje ct was to e x aminewhe the r the se two crow spe cie s that occur inPe nnsylvania ce nte r the ir winte r g e og raphic patte rnsin major urban are as ove r natural state park habitat.The answe r to this que stion is both ye s and no. Crowsare hig hly adaptive spe cie s, and can adjust the irsurvival habits to suit the ir curre nt e nvironme nt. The sere sults sug g e st that the re are occurre nce s of the sespe cie s in state parks, but a hig he r pe rce ntag e of thetotal numbe r of sig hting s te nde d to occur in urbane nvironme nts.

In this analysis, the re we re some limitations in the datathat we re obtaine d. The re we re sig nificantly fe we r Fishcrow sig hting s than those of Ame rican crows. Like ly,this is due to the nature of how the data was cre ate d.Ebird is a citize n scie nce org anization, so some of themore novice obse rve rs may not know the ide ntifie rsthat diffe re ntiate the two spe cie s. This would re sult inhig he r numbe rs of Ame rican crow sig hting s be ingre porte d, as Fish crows may not be a familiar spe cie sto be g inning birde rs.Additional re se arch on this subje ct should furthe re x amine individual locations within both of the sehabitat type s the se common spe cie s te nd tocong re g ate during the winte r months. The se mayinclude particular roosting or fe e ding site s, and the ircharacte ristics. The more we know about theg e og raphic and be havioral patte rns of the se spe cie s,the more we can do to prote ct the m while the y are stillcommon.

American Crow (Corvus brachyrhynchos) roosts ontop of Old Main, Shippensburg, PA November 2015

In OutIn 1.17 6.86Out 48.21 43.75

In OutIn 0.98 3.23Out 68.19 27.6

Fish Crow

State

Parks Urban Areas

American Crow

State

Parks Urban Areas

01020304050607080

State Park Urban

Perce

nt of

Sighti

ngs (%

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Habitat Type

American CrowFish Crow

Figure 1: Flowchart illustrating the methodsused to perform the analysis on both speciesof crows.