RECENT LITERATURE Editedby Edward H
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RECENT LITERATURE Editedby Edward H. Burtt, Jr. BANDING AND LONGEVITY (see also 15, 37) 1. Ring loss from Canada Geese.C. B. Thomas. 1979. Bird Study 26:270-271.- Rate of lossfrom a population of Canada Geese (Branta canadensis)marked with metal and engravedplastic rings in Yorkshireand Scotlandwas 2.3% per annum for metal and 1.7% for plasticrings. However the author presentsdata for only four yearsand assumes lossto be linear with time. Double lossis justifiably ignored, but for a semi-tamespecies it is worth notingthat both maybe removedfor souvenirsor during veterinarytreatment. Neither the pattern of metal ring used (both a clip and a heavier butt are specifiedfor CanadaGeese) nor the material(both monel and incoloywere in useat the time) is given, and the methodof closureis not mentioned(overlap of butt ringsprevents gaping from springback).--P.J. Belman. 2. Lossof weight and legibility of bird rings. M.P. Harris. 1980. Ringing& Migr. 3:41-48.--This is an historicalperspective that chroniclesring wear on the aluminum bandsin generaluse in Britain until 1965which, despite their shortuseful life on marine species,are still widely used in many countrieson groundsof cost. Monel, although an improvement, did not solve the wear problem for several speciesand has now been supersededby incoloywhich, while offering the required performance,is expensiveand likely to be replacedeventually in Britain by an appropriate grade of stainlesssteel.--P. j. Belman. 3. Report on bird-ringing for 1978. R. Spencerand R. Hudson. 1979. Ringing& Migr. 2:161-208.--This forty-secondreport on ringingin Britainand Ireland is the third to appear in revisedformat in thisjournal. The first 33 were publishedin BritishBirds and the next six as supplementsto Bird Study.With the move to Ringingand Migration have come two major changes:(1) the more carefully written introductiop attemptsto compareyear to year fluctuationsin the ringing totalswith ringing effort and abnormal weatherto assesspopulation change and, (2) the recoverysection provides species sum- maries with tablesof recoveriesfi•r all speciespublished at 5-year intervals.Maps and a temporal breakdown of recoveriesfor selectedspecies are occasionallypublished. The 1976 report contained the first 5-year summariesand was the same length as earlier reports,64 pages.The lasttwo are condensedto 48 pageswith the omissionof the 5-year tableswhile the number of maps is doubled.--P. J. Belman. MIGRATION, ORIENTATION, AND HOMING (see also 55, 59, 67, 89) 4. The significanceof the LesserBlack-backed Gull to models of bird migration. R. R. Baker. 1980.Bird Study27:41-50.--Recoveries of deadLarusfuscus originally band- ed in Britain showthat adultshave shiftedtheir winter range steadilynorthward during the last 15 years.This flexibilityof migration routesand seasonalranges seems contra- dictor)'to the relativelyfixed, internalprograms predicted by clock-and-compassand goal- area modelsof bird navigation,but is consistentwith an exploratorymodel, wherein youngbirds learn migratoryroutes and rangespartly through individualwandering and partly through associationwith or observationof experiencedadults. One intriguingob- servationthat supportssuch socially mediated learning is that adultsbegan the southward migrationin fall with youngbirds, but turned backnorth in midwinterto leavethe young birds in southernwinter ranges.Thus adults have showna northward shift in winter distribution,but first-yearbirds have retained earlier migratory patterns.--ScottR. Rob- inson. 5. An introductionto radar ornithology.[Einfuhr/ing in die Radarornithologie].J. Jellmann.1979. Gebiet der Vogellrunde6:249-261 .--This is an excellentintroduction to 72 Vol.•2, No. 1 RecentLiterature [73 the basicconcepts of radars, and how radars can be usedin ornithologicalresearch. The author covershow range information is obtainedand how bird echoesappear on both A- scope(oscilloscope) and PPI (Plan-Position-Indicator)displays. The discussionof the func- tional aspectsis limited to a blockdiagram that is describedin non-technicalterms. The three generalcategories of radar (3 cm, 10 cm, and 23 cm wavelength)are discussedin regardsto ornithologicalresearch.--Robert C. Beason. 6. The migration of coastalwaders from the Palaearcticacross Africa. R. J. Dow- sett. 1980. Gerfaut 70:3-35.--Many speciesthat winter on the coastin Africa alsooccur inland during migration,especially in fall migration.Generally there are no comparative data to indicatethe proportionof a speciesthat migratesacross Africa, but numberscited suggesta large proportionof somespecies migrate acrossland. Seasonaldifferences are explainedby suggestingthat the fall birds are in poor conditionand feed as they move southacross inland areas,whereas spring birds may be in good conditionto fly thousands of kilometerson their flights and so may overtly mostof Africa. Fifteen speciesare consideredand their seasonalrecords inland are documented. Maps are included for Terek Sandpiper (Xenuscb•ereus), Ruddy Turnstone (Arenaria i,•terpres),and Sanderling(Calidris alba). Species observed most frequently in large num- bers inland were the Sanderlingand Black-belliedPlover (Pluvialissquatarola). All inland or coastalobservations of Dunlin (Calidrisalpina) were rejected by Dowsett as probable misidentificationsof Curlew Sandpiper (Calidrisferrugi•ea) or Broad-billed Sandpiper ( Limicolafalci•ellus). Curiously only the waders (Haematopodidae, Charadriidae, Scolopacidae)which breed in the Palaearcticand winter more or lessexclusively on the African coastsare considered.The Curle•' Sandpiper, which is the most abundant coastalwader in South Africa, is not discussedbecause some of the inland recordsare apparently wintering recordsand not in passage.The arbitrary exclusionof half of the speciesof Palaearctic waderswintering at all in inland areasreduces the interestin the paper. It is alsodifficult to know to what extent the records discussed reflect the abundance of the birds or of observers.--RobertB. Payne. 7. On the spring migrationof palaearcticbirds acrossthe westernSahara. [Zum Frfihjahrszugpal•iarktischer Vogel fiber die westlicheSahara.] W. Haasand P. Beck.1979. J. Ornithol. 120:237-246.--Exhaustedor dead migrantsand killed controlswere analyzed for fat and •vatercontent and for chlorinatedhydrocarbons. Small speciesfailed to cross the Saharabecause of depletedfat stores,while larger migrantsfailed becauseof depleted water stores.Pesticides did not appearto influencemortality.--Robert C. Beason. POPULATION DYNAMICS (see also 3, 17, 23, 37, 50) 8. Mortality rates of the Great Tit (Parusmajor) in a northern population. M. Orell and M. Ojanen. 1979. Ardea 67:130-133.--Annual mortalityrates of Great Tits were estimatedon the basisof 4002 fledglingsringed in northernFinland between 1968-1977. From these, 163 were recaptured in the area as breedersin later years and 44 were recoveredafter their first January of life. Males showeda lower mortality rate (48.7- 54.9%) than did females(51.7-55.2%) althoughdifference between sexes seemed smaller than in populationsfarther south.Overall mortality of adultsis perhapsslightly greater than in populationsof central and westernEurope. Mortality amongyoung birds up to their first breedingwas 78.1%.•. M. White. 9. Hobby studies in England and Germany. D. Fiuczynskiand D. Nethersole- Thompson. 1980. Br. Birds 73:275-295.--Although highly successfulin England, the Hobby (Falcosubbuteo) is endangeredin Germany.This articleexemplifies one of the main strengthsof BritishBirds from my point of view. Data on breedinghabitats, numbers of breeding individuals,breeding density and spacing,descriptions of nest and nest-trees, breedingphenology, and clutchsize are conciselypresented for populationsin England and Germany. The possibilitythat pesticidecontamination may be the causeof the Hobby'sendangered status is discussed.Suggestions for further study are given and in- 74] RecentLiterature J.Field Ornithol. Winter 1981 clude precisestudies of populationstatus, breeding biology, and conservation.--Patricia Adair Gowaty. 10. Clutch size, breeding success,and parental survival in the Tree Swallow (Ir- idoprocnebi½olor). D. De Steven.1980. Evolution34:278-291.--De Stevenoffers one of the better conceivedand more intriguing "twinning"experiments reported to date. Her studywas designed to explicitlytest Lack's "maximal" clutch size hypothesis that in nidic- olousbirds clutchsize should correspond to the maximumnumber of young parentscan raisegiven current food limitations,as well as recentmodifications that predictan "op- timal" clutch smallerthan the mostproductive owing to the negativefeedback of larger broodson subsequentparental survivorship. During her study,more young were fledged from experimentallyenlarged broods than from controls.Brood enlargementincreased variabilityin nestlinggrowth, but wasnot associatedwith any differencein mean fledging weight.Most tellingly, the return rate of fledglingsas first-time breeders (and by inference survivorship)was independent of brood size.Not only wasthe natural modal clutchnot the mostproductive, but eventhe mostproductive natural clutch was less productive than the experimentallyenlarged broods. Such data unequivocallyfalsify Lack'smaximal, or food-limited,clutch size hypothesis for the Tree Swallow.To unsettlematters further, De Stevendemonstrated that femalesraising enlarged broods did not suffer disproportionate weight lossor decreasedsurvivorship as measuredby returns. In fact, for older females the experimentalshad a higher