An Experiment in Songbird Management
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Vol.194o•7-] a McAx•:, SongbirdManagement 333 AN EXPERIMENT IN SONGBIRD MANAGEMENT BY W. L. MCATEE A PROJECTfor increasingthe numberof birds to controlnut weevils in an orchard of blight-resistantchestnuts at the Bureau of Plant Industry Experiment Station near Glenn Dale, Maryland, was carried on cooperativelyby that organizationand the U.S. BiologicalSurvey from 1926to 1931. Entomologicaland managementresults have been reportedin the paperslisted in the terminal bibliography,and the more strictlyornithological findings are presentedin this communica- tion. The area involved was about two and one-half acres the first two yearsand three and a half the last four. It waspretty fully occupied by the chestnutorchard and a rosegarden, yet had ample openings. A bird bath, a martin house, and at the maximum 98 individual bird boxes including five sizeswere installed. Responsewas good and, there being no hole-nestingspecies on the tract before, the threefoldto fourfold increasein birds wasclear gain. The bird pop- ulation was multiplied but the nut weevilswere not perceptiblyre- duced in numbers; their increase,however, may have been checked. Ornithologicalgleanings are here summarizedas 'Nest Analyses' and 'Nesting Results.' NEST ANALYSES On November 18, 1926, E. A. Preble helped me to collect twenty birds' nestsfrom trees in the experimentalchestnut orchard. Ma- terials usedin twelve of these (consideredto be correctlyidentified) are reportedon here. The insectsand spidersusing thesenests as winter quarterswere treated in papersby McAtee (1927b) and Malloch (1927b). Building Materials Tree Nests Robin.--Three nestsagreed in having weed stalks,dry grass,and mud in their foundationsand fine dry grassfor linings. One had a few twigs and another someleaves in their bases. In nest No. lva few grassseeds in the mud layerhad sprouted,and in connectionwith an embeddedgarlic bulblet with its thread-likeappendage, added fine greenfilaments to the lining. Nest No. 2 held a stratiomyidfly larva (Odontorayia)and three small bivalves (Pisidiuraabditura), •34 McATEE;Songbird Management L[Auk July aquatic forms, undoubtedlygathered with the mud. Nest No. 3 also had a garlic bulblet as in No. 1. Catbird.-Twelvenests were madeof the followingmaterials, the frequencyof useof whichis indicatedby thenumbers in parentheses. Foundation:coarse weed stalks (11), leaves(7), paper (7), coarse twigs(5), red-cedarbark (4), grass(3), chestnutbark (1), andlumps of dirt (1). Lining:in eachcase (12) madeexclusively of rootlets. Box Nests On September23, 1926,the contentsof all bird boxesand on July 8 andAugust 16, 1927,of thosenot in actualuse by birds,were re- movedto the laboratoryfor study. Materialsused by the different birds(listed in thesame order as in Table 1) arehere noted. Starling.--Asa rule the Starlingnests were of slight construction and with little differentiationbetween foundation and lining. In six nestsanalyzed, weed stalks (including Solidago) and grass (including Andropogon)were used in thefoundations of six and five,respectively. Other objectswere straws(up to 11 incheslong), leaves,chestnut spikes,twigs, vines (up to 18 incheslong), and a pod of wild bean (Strophostiles).The 'lining' includedfeathers in four nests,red-cedar barkin two,and leaves in two. Observationsthrough five years showed that most Starling nestsin actual usewere adornedwith one or more freshleaves of yarrow (Achilleamille[olium). House Wren.-Thirty-threecomplete or partial nestswere analyzed. Foundationsincluded (in the numberof nestsindicated): twigs (33), feathers(16), chestnutspikes (13), wool (12), leaves(7), cord (6), and weedstalks (5). Materialsused in fewerinstances were: rootlets, red-cedarbark, cotton, grass, chestnut shell, paper, a largefragment of snailshell, exoskeletons of milleped and sowbug,and a spidercocoon. The twigswere characteristically coarse and includedsome up to eightinches in lengthand a fewthat were branched. Rose twigs with plentifulthorns were frequently employed, and in a few casescallow youngwere raised in suchnests with little or no cushioningto pro- tect them from the spines. The twig basesof nestswere often from four to six inchesdeep. Flecksof wool and cottonwere scattered throughthe twig basesto no conceivablepurpose. The lining of the 33 nestsincluded grass in 19 cases,hair, chieflyhorsehair, in 16, feathers in 13, and rootlets in six. Other items were red-cedarbark, chestnutspikes, weed stalks,and grass. The material'in one nest, loosenedup in the processof' analysis, filled a tWo-gallonbucket. EnglishSparrow.-Five nests studied were bulky and composed chieflyof dried grassand feathers,the latter formingmost of the Vol.194o•7'] a McA'r•, SongbirdManagement 335 lining in each instance. Other substancesused, chiefly in the base, included:red-cedar bark, weed stalks,and rootlets. The nestsap- parently are relined with feathersas excreta accumulate,and there may be severallayers of suchbedding. Bluebird.-In eight nestsgrass predominated both in bases(7) and cups (5). Other foundationmaterial includedweed stalks (4), twigs ($), leaves(2), and feathers(1); and lining, feathers(2). Purple Martin.-The martins scarcelycan be said to make nests, bringing in to their housesa miscellaneouscollection of litter and bric-a-brac. Plant fragmentsincluded straws (up to 16 incheslong) and other grassstems (including Andropogon),weeds (representing the generaRumex, Silene,fragaria, Oenothera,Solanum, and Plant- ago), leaves,twigs (up to nine incheslong and a quarter of an inch thick) includingsome of rosewith thorns,fragments of the wall of cornstalk,a pod of partridgepea (Chamaecrista),and bulbletsof gar- lic. Odds and endswere: bits of oystershelland porcelain,pebbles, lumps of day, and plant labels (one of wood measuring0.5 by 3.5 inches). CrestedFlycatcher.-This bird's housekeepingwas about on a par with that of the martin. Materials rudely piled in a thin nest in- cluded:weed stalks, rootlets, a twig of sassafraswith flowersand green berries,maple samara,onion skin, and snakeslough. It is of interest to notethat a pieceof thislast substance also was incorporated into the only Tufted Titmousenest that wasbuilt in the boxes. (A summary of the useof snake-skinsby birdsmay be foundin Contrib. 11, Baylor UniversityMuseum, 12 pp., 1927,by John K. Strecker.) Food Remains Examinationof nests,particularly those in bird boxes,is a profit- able methodof learningabout the foodof birds,that hasas yet been very little exploited. The resultshere givenprobably are typicalof whatcan be expected.Care is necessary,ascontamination is probable in direct proportionto the ageof the nest. Someintrusive material as that broughtby miceis easilyrecognized, but that introducedby invadingbirds may be more difficultto eliminate. In casesof doubt, recordshave beenrejected as hasalso all evidencefrom boxesknown to have been usedby more than one speciesof bird. For safety's sakeall scavengerforms have been omitted, though possibly some of them were food items. Grateful acknowledgmentis made in connectionwith theserecords for identificationsof: dragonflies(to C. H. Kennedy),beetles (L. L. Buchanan),and Diptera and Hymenoptera(J. R. Malloch). 336 McATEE,Songbird Management L[-Auk July Asterisksfollowing namesin the lists denote insectsof enough economicimportance to be referred to in the list of commonnames approvedby the AmericanAssociation of EconomicEntomologists. Variousspecies besides those so designated,however, are known to be destructive. Tree Nests Robin.--Plant remains:seeds of sassafras,poison ivy, and smooth sumac. Animal remains:spotted cucumber beetle (Diabrotica•2-punctata), ground beetle (Carabidae),caterpillar, and spider. Catbird.--Plantremains: seeds of mulberry,sassafras, and cultivated cherry. Animal remains: dragonfly,cricket (Orocharissaltator), stink-bug (Pentatomidae),ground beetle,leaf-chafer (Scarabaeidae), locust leaf- miner (Chalepusdorsalis), weevils, caterpillars,ants, yellow jacket (Vespula),and bee (Agaposternon). Box Nests Starling.-Plant remains: seedsof mulberry, sassafras,rose, black- berry, cultivatedcherry, and dogwood. Animal remains:earthworm cocoon, centiped, millepeds, grasshop- pers (includingArphia xanthopteraand Melanoplus),crickets (in- cludingGryllus and Nemobius),stink-bugs (Euschistus sp., E. tristig- rnus, Hyrnenarcys nervosa, and Peribalus lirnbolarius, assasin-bug (Sinea),tiger beetle (Cicindela),ground beetles (including Calosorna calidurn,C. sayi,Poecilus sp., P. lucublandus,Percosia obesa, Galerita, Cymindis,Chlaenius sp., C. tomentosus,Cratacanthus dubius, Harpa- lus caliginosus,H. erythropus,H. pennsylvanicus,Triplectrus rusticus, Anisodactylus, Ornophron), fireflies (Chauliognathus rnarginatus), click-beetles(Monocrepidius auritus, Hernicrepidius rnernnonius, Melanotus), darkling beetle (Opatrinus notus), dung beetles (Can- thon laevis,Bolbocerosorna farcturn, Geotrupes), leaf-chafers (Diplo- taxis, Phyllophagacrenulata, P. fraterna, P. luctuosa,P. tristis,Ano- rnala, Pachystethuslucicola, Dyscinetustrachypygus, Ligyrus gib- bosus%Euphoria herbacea),leaf beetles (Leptinotarsa•o-lineata% Zygograrnrnasuturalis, Disonycha triangularis, Chaetocnerna, Chalepus dorsalis*), weevils (Epicaerus irnbricatus*, Brachyrhinus ovatus, Hypera punctata*, Hyperodes,Listronotus, Gyrnnetron tetrurn, Chal- coderrnuscollaris, Tyloderma foveolata, Sphenophorus inaequalis), caterpillarsand chrysalides(Lepidoptera), parasitic wasp (Ichneu- moninae),paper wasp (Pollsres),honeybee (Apis rnellifera),ants (in- Vol.tl7-] McATi;E,Songbird Management