160
General Notes
Fig. I.
[Auk, Vol. 94
Rock Dove nest constructedprimarily of wire.
(3%). I pipe cleaner, and 3 feathers comprising the remainder. The plant material was mainly wood
splinters.
Thenestwas12.0cmhighand23.0cmin diameter
•nd weighed
617.5g.In construction
it was
similar to other Rock Dove nests.Although material had been added one pieceat a time and the nest was
not well woven, it could be lifted without falling apart. The noncompressibilityof the wire explains the
nest'sunusual height. The longer wire (> 16.0 cm) and plastic debris were at the baseand sidesof the
nest, while smallerbits of wire (< 9.0 cm) and plant material comprisedthe centerof the nest.According
to Nowland (pets. comm.) man>-piecesof wire were scattered on the ground within several hundred
metersof the nest site. The nearestvegetationwas approximately400 m away.
Bent (1948, U.S. Natl. Mus. Bull. 195) mentions that House Wrens (Troglodytesaedon) have been
known to build nestsexclusivelyof metal, but he doesnot discussthe success
of theseattempts.Possibly
this nest failed becauseit provided no insulationto help retain the heat generatedby the broodingadult,
and any metabolic heat produced by the squab was probably drawn off via conduction. I thank R. S.
Nowland and R. V. Dietrich, who found and donatedthe nest.respectively.--RoBERTL. PATERSON,
JR.,
Department of Biology, Central Michigan University, Mt. Pleasant, Michigan 48859. Accepted 10 Oct.
76. This note was subsidizedby Central Michigan University's Faculty Researchand Creative Endeavors
Grant
#20-21315.
Red-cockaded Woodpeckers and pine red heart disease.•The Red-cockaded
Woodpecker
(picoidesborealis)is unusualfor its consistentuseof living pine treesas cavity sites.Steirly( 1957)attributed
the ability of thesewoodpeckersto useliving pinesto the presenceof red heart disease(pomespini), a fungus
that weakensthe heartwoodand thus facilitatesexcavation.Someauthors(e.g. Steirly 1957;Ligon in
Thompson1971:30) have maintainedthat red heart diseaseis necessaryfor the woodpeckersto excavatea
cavity successfully
while others(e.g. Beckettin Thompson197I: 87) have suggested
that the Red-cockaded
Woodpeckers'use of pines with red heart diseaseis merely a function of the age of trees, rather than a
requirement for excavation. The purposeof this paper is to present data on the incidenceof red heart in
Red-cockadedWoodpeckercavit.vtreesand to clarify the relationshipof the diseaseto tree useby the birds.
During 1972 and 1973 I located 265 Red-cockaded Woodpecker cavity trees on Noxubee National
Wildlife Refugeand the MississippiStateUniversity Forestin Noxubee, Winston,and OktibbehaCounties
in Mississippi.The upland forest there is secondgrowth consistingof mixed pines and hardwood. The
dominantpinesare 1oblolly(Pimtstaedal. with occasionalscatteredshortleafpines(Pinusechinata).All but
January 1977]
General Notes
TABLE
161
1
CHARACTERISTICS OF RED-COCKADED WOODPECKER CAVITY TREES IN EAST-CENTRAL MISSISSIPPI
N
Mean
Range
SD
Tree height (m)
Tree age (years)
258
259
29.8
75.9
16-40
40-116
3.8
12.1
dbh (cm)
Bark thickness(mm)
246
259
60.4
23.2
26-87
9-45
9.9
5.8
oneof the cavity treeswereloblollypines;the exceptionwasa shortleafpine. Each of the 615 cavitiesin these
treeswas classifiedin one of four categories:(1) fresh--wet pine gum on the tree flowing from "resinwells"
around a fully excavatedcavity; (2) dry--dried, white pine gum around a fully excavatedcavity; (3)
old--blackenedand deterioratingpine gum arounda fully excavatedcavity;(4) cavitystart--not a fully
excavatedcavityandgenerallywith noactiveor inactiveresinwellsand noappreciable
gumpresentonthe
tree aroundthe entrance.Where possible,I recordedthe followinginformationfor eachcavity tree:(1) tree
heightin meters,measuredwith a Haga altimeter;(2) tree age, measuredby incrementboringat 1.5 m and
adding3 yearsto the countedannuli;(3) treediameter(dbh)in centimeters
(at 1.5 m); (4) bark thickness
at
breastheight,measuredin mm with a bark thicknessgauge;(5) presence
or absence
of red heartat 1.5 m
andat cavityheight,determinedby incrementboringandsometimes
alsoby the presence
of conks(fruiting
bodiesof the fungus).The incrementboringsamplesfrom treeswith red heart diseaseend with soft,friable,
infected wood of a dark red color. I consideredculturing of increment bore samplesunnecessaryas no other
trunk rot of thesepineshas been reported(Hepting 1971: 367). Estimatesof tree age were often difficult
when red heart was presentat 1.5 m. Age, dbh, and presenceor absenceof red heart at 1.5 m and at 10 m
were also measuredfor 40 loblolly pines that were within woodpeckercoloniesand that looked similar to
cavity trees but had no woodpecker cavities.
Basic statistics for cavity tree characteristicswere calculated using UNIVAR, a Fortran computer
program written by D. M. Power. Analysisof varianceor a test for equality of two percentages(Sokal and
Rohlf 1969) was used to compare data setsat the 0.05 level.
The characteristics of all cavity trees and trees with and without red heart diseaseare summarized in
Tables 1 and 2. Most treeswith completedcavities(90%) had obvioussignsof red heart disease,while 67%
of the treeswithout red heart containedonly cavity starts.Those cavity treeswith red heart disease,while
apparentlyaveragingonly 6.2 yearsolderthan thosewithout the disease,in fact probablyaveragedat least8
to 10 years older as red heart had frequently destroyedinner annual rings. The diseasedtrees also were
significantlylessin diameterand had thinner bark than healthy cavity trees.At 1.5 m and at cavity height,
the lowestincidenceof red heart diseasewas in treeswith only cavity starts(Table 3). In eachcase,this level
of incidencewassignificantlylowerthan the incidencefor treeswith fully excavatedcavities.Incidenceof
red heart at cavity height was nearly double that at 1.5 m.
The 40 noncavitytreesmeasuredwithin Red-cockadedWoodpeckercoloniesaveraged67.8 yearsold,
49.0 cm dbh, and 21.8 mm bark thickness. None showed a trace of red heart diseaseat either 1.5 or at 10 m.
Few largepineswereavailablethat werenotbeingusedascavitytreesby the birds,hencethe lowerageand
sizeof treesin this sample.It is significantthat the rangeof measurementsfor the 40 treeswithout cavities
fell entirely within the range for cavity trees, and that cavity trees within and below the range for trees
without cavitieshad a high incidenceof red heart.
TABLE
2
CHARACTERISTICS OF RED-COCKADED WOODPECKER CAVITY TREES WITH AND WITHOUT
RED HEART DISEASE EVIDENT AT CAVITY HEIGHT
With red heart
N
Mean
Without
red heart
SD
N
Tree height (m)
Tree age (years)
153
152
28.9
77.0
3.7
11.6
50
50
29.4
70.8
3.4
12.0•
dbh (cm)
153
57.2
9.4
50
64.1
7.9 •
Bark thickness(mm)
148
21.8
5.5
50
24.6
5.5 •
Significant difference (P -< 0.05) between trees with and without red heart disease
Mean
SD
162
General Notes
TABLE
INCIDENCE
[Auk, Vol. 94
3
OF RED HEART DISEASE IN RED-COCKADED WOODPECKER CAVITY TREES
Cavity status
Start
Fresh
Dry
Old
At 1.5 m
N (trees)
92
88
32
53
RH (%)
No RH (%)
Uncertain (%)
30.4
67.4
2.2
38.6
60.2
1.1
37.5
59.3
3.1
45.3
50.9
3.8
387
55.3
36.4
101
73.3
12.9
61
77.1
4.9
8.3
13.8
18.0
66
68.2
9.1
22.7
At cavity height
N (cavities)
RH (%)
No RH (%)
Uncertain (%)
Early stagesin the developmentof red heart diseaseare not detectableby grossexaminationof increment
bore samples.Further, infectedwood couldbe virtually removedby the bird's excavation.Consideringonly
thesepossibilitiesand the high percentageof bore samplesfor which the presenceor absenceof red heart
diseasewas uncertain, it would seempossiblethat the presenceof red heart is requisitefor the Red-cockaded
Woodpecker'sexistence. Other evidence increasesthe probability that the birds require weakened
heartwood for their excavations.Affeltranger (in Thompson 1971: 96) statesthat the sporesof Fomespini
are wind disseminatedand that inoculationmust occuron brancheswith heartwood or where large wounds
are presentin the trunk. Thesewoodpeckersmay spenda year or moreexcavatinga cavity, at timesleaving
the excavationuntouchedfor months (Baker in Thompson 1971: 44; pers. obs.). This behavior, associated
with the fact that the lowestincidenceof red heart diseasewasfoundin treeswith only cavitystarts,suggests
that the birds may excavate only until they reach soundheartwood and that the cavity start may provide a
site for infection, after which the woodpeckerscomplete excavation.
The lesserdbh and bark thicknessnotedfor cavity treeswith red heart when comparedto cavity trees
without red heart is likely symptomaticof the disease.On the otherhand, the birds'characteristicflaking of
bark from active treesmay accountfor somedifference. Scalingof bark from noncavity treeswhile the birds
foragemay facilitate infectionby red heart to the extent that it makesthe tree more susceptibleto mechanical
injury.
Finally, the minimum incidenceof red heart diseasein the Red-cockadedWoodpeckercavity trees
discussed
here (75%) is significantlyhigher than the 2 to 40% incidencereportedfor loblolly pinesfrom other
areas(Nelson1931,Hepting and Chapman 1938,Gruschowand Trousdell 1958).The relationshipbetween
the birds and the fungusdoesnot seemto be oneof chancecoexistence.The presenceof red heart is probably
required for the normal, completeexcavation of cavities by Red-cockadedWoodpeckersand infection of
pines by red heart is probably facilitated by the birds' activities.
For this woodpecker to recover from its endangered status (Jacksonin Thompson 1971: 4) we must
provide the older trees that are naturally susceptibleto red heart diseaseor we must begin a program of
artificially infectingyoungerpines(Affeltrangerin Thompson 1971: 96) in hope that the birds will make
greateruseof them for cavities.The latter courseseemsremotelyfeasibleas a few nestcavitieshave been
found in treesapproximately40 years old in diverseparts of the bird's range (e.g. Florida--Ligon 1970,
Crosby 1971; South Carolina--Hopkins and Lynn in Thompson 1970: 140; Mississippi•pers. obs.). The
former courseof actionis the only coursethat couldresultin anythingmore than a "showcase"population.
Unfortunately,presentmanagementguidelinesfor our nationalforests(whereI estimate75% of existing
Red-cockadedpopulationsoccur)includea 60-yearrotationfor lobloll3'pine, an 80-yearrotationfor longleaf
pine (Pinuspalustris),and similar rotationsfor other southernpines(M. Lennartz pets. comm.). These
rotationswere establishedto maximize timber production and minimize lossesto suchfactorsas red heart
disease.It is no accidentthen that eachpine speciesis harvestedbeforeit reachesthe primeagefor red heart
(Hepting 1971)and cavity excavationby thesewoodpeckers(Thompsonand Baker in Thompson 197I: 170).
The U.S. Forest Service is developingnew managementguidelinesfor the Red-cockadedWoodpecker
(Holbrookpets. comm.)and hopefullythesewill allow for expansionof the speciesinto new areasas well
as for maintenanceof the existingfragmentedpopulations.
I am grateful for the assistanceof severalstudentswho worked with me on Red-cockadedWoodpeckers
and for the cooperationand assistance
receivedfrom personnelat NoxubeeNational Refugeduringthe past
January 1977]
General Notes
163
4 years.Financialsupportfor thisstudywasprovidedby NSF grant GB-33984. Computertime wasmade
availableby the Thomas E. Tramel ComputingCenter at MississippiState University.
LITERATURE
CROSBY,
G.T.
CITED
1971. Ecologyof the Red-cockaded
Woodpeckerin the nestingseason.Unpublished
M.S. thesis,Gainesville, Univ. Florida.
GRUSCHOW,G. F., & K. B. TROUSDELL. 1958. Incidence of heart rot in mature loblolly pine in
coastalNorth Carolina. J. Forestry 56:220-221.
HEPTING,G.H.
1971. Diseases
of forestand shadetreesof the United States.U.S. Dept. Agr. Forest
Serv. Agr. Handbook No. 386.
--
& A.D. CHAPMAN.1938. Losses
fromheartrot in twoshortleaf
andloblollypinestands.
J.
Forestry 36: 1193-1201.
LIGON,J.D.
1970. Behaviorandbreedingbiologyof theRed-cockaded
Woodpecker.
AukS7:255-278.
NELSON,R.M.
1931. Decayin loblolly pine on the Atlantic CoastalPlain. Virginia ForestServ. Publ.
43: 58-59.
SOKAL,R. R., & F. J. ROHLF.
STEIRLY,C.C.
uralist
1969. Biometry. San Francisco, W. H. Freeman and Co.
1957. Nestingecologyof the Red-cockaded
Woodpeckerin Virginia. Atlantic Nat-
12: 28f•292.
THOMPSON, R. L. (El).).
1971. The ecology and management of the Red-cockaded Woodpecker.
Tallahassee,Florida, Bur. SportFish. Wildl., U.S. Dept. Interior, and Tall Timbers Res. Station.
JEROMEA. JACKSON,
Department of Zoology,MississippiState University, MississippiState, Mississippi 39762. Accepted 30 Sep. 75.
Unusual food item of Franklin's Gull.--Investigations
ontheecology
of birdsarenecessary
for
their conservation,
and foodhabitsdata seemjustifiedin addingto the total ecological
picture.While
preparinga museumstudyskin(DLD 159)of an adult(sexunknown,weight325g)Franklin'sGull (Larus
pipixcan)collectedby the first authoron 1 October1972at the Maryville seweragelagoons,Nodaway
County, Missouri,we found 23 stinkbugs(Pentatomidae)and one large adult prairie vole (Microtus
ochrogaster)
in thecrop,andoneadultwesternharvestmouse(Reithrodontomys
megalotis)
in thegizzard.
The Franklin's Gull is c•)nsideredto be almostcompletelyinsectivorous
and the stinkbugswere not
surprisingalthoughBent (1921, Life historiesof North Americangullsand terns,Washington,USNM
Bull. 113: 171•171)doesnot specificallymentiontheseinsects.The mice were surprising;the only
referencewe have been able to find on any vertebratefoodsof this gull is Bent (op. cit., 171) who
speculates
that possiblysmallfish mightbe eaten.The feedinghabitsof this"prairie"gull duringmigration are well knownas it oftenfollowsthe farmerand plow duringspringand fall to feeduponfreshly
exposedgrubsand worms.During this time otheranimalssuchas mice are frequentlyexposedby the
plowingand subjectto heavy predation.The habit of hawks followinga plowmanare well known.
Evidently the Franklin's Gull is an opportunisticfeederand will sometimesconsumevertebratessuchas
mice. It is not known whetherthis individualwas a scavengeror a predator,but the consumptionof two
freshmiceat the sametimemakesus suspect
predation.The intactprairievolewasa particularlylarge
individual; we marveled that so large an item would be swallowed whole.--DAVID A. EASTERLAAND
DOYLEL. DAMMAN,Departmentof Biology,NorthwestMissouriState University,Maryville64463.
Accepted 29 Sep. 75.
The Greater
Shearwater
in the northern
Gulf of Mexico.--The
first record of this shearwater
(Puffinusgravis)from the Gulf of Mexicowas not from Galvestonon 4 November1973,as claimedby
Arnold(1975,Auk 92:394), but from DogIslandnearSt. Marks, Floridaon 29January1950,specimen
in
Florida State University, H. M. Stevenson(1950, Florida Naturalist 23: 71). Arnold wrote that this
shearwater is "known from the United States only along the Atlantic coast from eastern Florida
northward"(Murphy 1967,Serialatlasof the marineenvironment:Distributionof North Atlanticpelagic
birds,map 8B, Amer. Geogr.Soc.)and that he hasbeen"unableto locateany otherrecordsfor the Gulf
coastof the United Statesor for any other part of the Gulf of Mexico region."
After 1950 the specieswas recordedin the northernGulf of Mexico in 1958, 1964, 1966, 1970, 1971,
1972, 1973, and 1974. In 1975Purrington(Amer. Birds 29: 69) remarked that "theseobservationslend
substanceto the conclusionthat the Greater Shearwaterprobably occursannually along the n. Gulf
coast."