Unusual Nesting of the Lesser Kestrel (Falco naumanni

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Mikulov, Czech. Republic. BIBER, J.P. 1996. International action plan ibr the Lesser ... que, NM 87104 U.S.A.; e-mail ad
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J RaptorRes.38(2):161-163 ¸ 2004 The Raptor ResearchFoundation, Inc.

UNUSUAL NESTING OF THE LESSERKESTREL(FALCONAUMANNI)IN THESSALY,GREECE CHRISTOSVLACHOS,1 DIMITRIS BAKALOUDIS, AND EVANGELOSCHATZINIKOS AristotleUniversityof Thessaloniki, Departmentof Porestryand Natural Environment,Laboratoryof WildliJkand FreshwaterFisheries,P O. Box 241, 54006 Thessaloniki,Greece

KEYWOP,DS: LesserKestrel;Falco naumanni; breedingsuccess; fledglings;nesting. The Lesser Kestrel (Falco naumanni) is a small fhlcon

that breeds colonially and nestsmainly in walls or roofs of houses, stables, barns, castles or churches, as well as

•n tree holes, earth cliffL and in rocky outcrops (Cramp and Simmons 1980). Ahhough the specieswas considered to be one of the most abundant European birds of prey, it has suftkred from a massivepopulation decline in large parts of its western Palearctic range between the 1960s and 1980s (Cramp and Simmons 1980, Biber 1996), now is of global conservationconcern (SPEC 1 category), and considered to be vulnerable in Europe

(Hagemeijer and Blair 1997). The reasonsfor the dra-

ginning of the egg-layingstage. Nests' contents were checked every 15 d to record possiblereproductive ihllures, but in three periods they were checked more quently: (1) during the beginning of incubation to assess clutch size; (2) just after hatching to estimate hatching success, brood sizeat hatching,and date of hatching;and (3) during fiedging to record the number of young fledged (Steenhof1987). A pair which laid eggswasdefined as a reproductive pair, a successiBlly-breeding pmr was one that fledged at least one young, and breeding successwas defined as the percentage of successtiffterritorial pairs (Newton 1979, Steenhof 1987). Means _+SE are presented in the text and diflkrences (using the Mann-Whitney U-testand the Fisher's Exact test ibr 2 x 2 tables) consideredsignificantat 0• = 0.05. RESULTS AND DISCUSSION

matic decline include the reduction of thvorablenesting habitats (restoration and demolition of old buildings), and the intensification of agricultural practices(destrucnon and lossoftbraging areas,and the reduction of prey availability;Donfizar et al. 1993, Forero et al. 1996, Tella

A colony of 18 LesserKestrel breeding pairs, in an old building in Megalo Monastirivillagewasrecordedin 1998. The next yr, the local municipality demolished the old building and cleared away most of the debris because•t et al. 1998). was dangerousfor the people living in the area. Early in The trend of the Greek population, which comprises the next breeding season,the same numbers of Lesser ca. 14--15% of the European total, has been similar. In Kestrelpairswere recordedat the locationof the old buildGreece, the Lesser Kestrel shows a discontinuous distriing, as most of adult LesserKestrelsshow high fidelity to bution and now it is mainly concentrated in Thessaly, their breeding colonies(Serrano et al. 2001). We recorded where Hallmann (1996) in a preliminary report recorded a total of eight breeding attemptsof LesserKestrelsnest104 coloniesand a total of 2679 pairs. ing on the ground, 75% of which were successful. AlThe objectivesof the present study were to estimate though ground-nestingbehavior had not been observed the breeding successof Lesser Kestrels nesting on the betbre, the overall breeding successtbr these Lesser Kesground and in a ibM-run with hensand to comparethese trels wasslighfiyhigher than that recorded for the entire estimates to those of other colonies. populationin MegaloMonastiriin 1999 (69.7%, N = 33 pairs), but this differencewasnot significant(Fisher'sExSTUDY AREA AND METHODS

act test, P = 0.569; Bakaloudis et al. 2000). Megalo Monastiri is a small village at the southeastern There were no significantdifferencesin any reproducpart of the Larisa plain, central Greece. The village is sit- tive parameter between the colony that nested on the uated on the edge of a hilly terrain, surroundedby grassground and the population that nested on the buildings landsand agriculturalland, where the dominantcropsare of the village. The mean clutch sizewas 3.1 + 0.35 eggs, cereals and cotton, with small areas of almond trees. The altitude rangesfrom 50-120 m abovesealevel.The climate similar to the population in the village (3.5 + 0.22; •s thermo-mediterranean,with a mild rainy winter and a Mann-Whitney /Stest,P = 0.288). Eighty-fourpercent of dry and hot summer. The mean annual precipitation is 25 laid eggson the ground hatched successfully, resulting about 465 mm concentratedduring the winter. in a mean brood size at hatching of 2.6 -+ 0.26, which We located and monitored nestsfrom March-Septemwas similar to the mean brood size tbr the pairs nesting ber 1999. Most (75%) of the nestsweretbund during the on buildings (3.1 + 0.19, N = 26; Mann-Whitney gtest, incubation period, while the rest were lbund at the beP = 0.143). Two of tbur unhatched eggs disappeared about 14 d after the incubation had begun. In both cases E-mail:cvlachos@for. auth.gr large eggshellfragmentswere tbund and we suspectthat

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domestic cats (Felis catus) and rats (Rattus rattus) were

responsiblefor destroyingthose eggs.The mean brood sxzeat fledging per successfulpair waslower in the pairs nesting on the ground (2.67 + 0.33, N = 6) than the pairs nesting in buildings (3.09 q- 0.2, N = 23), but not significantlyso (Mann-WhitneyU-test,P = 0.371). The mean number of young fledged per reproductive pair that nested on the ground was 2.00 __+ 0.5 (N = 8) and dxd not

differ

ii•om

the mean

number

of kestrels

reared

by pairs that nested on the buildings (2.15 q- 0.29, N = 33; Mann-WhitneyU:test,P = 0.771). Seventy-six percent of 21 hatched eggson the ground produced fledglings successfully. Most chick mortality (80%) occurredwhen the adults deserted the nestsabout 20 d after hatching. Although there was indication of the causeof those losses, which could be due either to an accident to their

VOL. 38, NO. 2

stageof the nestlingperiod. The fact that LesserKestrel relies heavilyon prey speciesthat inhabit intensively-cultivated land, might be a causeof concern for the future. We also monitored the breeding successof five pairs found nesting in a fowl-run. The mean clutch sizewas3.2 eggs (SE = 1.5), brood size 2.8 young (SE = 1.3), and breeding success 60%. Sixty-ninepercent of 16 laid eggs hatchedsuccessfully and 91% percent of the hatchedeggs produced fledglings(N = 2). Betweenone and three hen eggswere also found in each kestrel nest. Also, one nest wasfound in a plasticbarrel with two eggs,but failed to produce young and another one in an oil barrel with two eggs,which fledged one young successfully. In conclusion,we suggestthat the unusual groundnesting observed,as well as the nesting in fowl-runsand in barrels, may be associatedwith the lack of other suitable nesting sites (Forero et al. 1996), the relative absenceof predators (Balibur 1955, Seago1967, Piechock• 1982, Village 1990) at this site and by the high fidelity exhibited by adults to their breeding colonies (Serrano

parents or to poor parental care, the leathered chicksin two broods (pairs D and H) died from starvation.In another case(pair C), the predated downychickwasfound closeto the nest with its siblingsand had probablybeen ktlled by a rat. No evidence of cannibalismwasobserved et al. 2001). •n the colony of LesserKestrel on the ground, as was informacion sobre 8 nidos de reported by Negro et al. (1992) for other colonies in RESUMEN.--Presentamos Spain. The proportion of nestsfailing during incubation Falconaumannique han hecho nido en el suelo debajo waslower than pairs nestingon the ground than nesting de los restosde un edificio antiguo demolido en Theson buildings(58.3%, N = 7). Conversely, broodsin nests salia,Grecia Central en 1999. Las variablesreproductivas on the ground (25%, N = 3) were more likely to fail than como tamapo de puesta en el momento del vuelo (3.1 those in buildings (16.7%, N = 2; Fisher'sExact test, P huevospuestos),el tamapode pollada (2.6 pollos)y 6xito = 0.045). This was due mainly to the higher predation reproductor (2.6 pollos) no tienen diibrenciasimportanpressure during the nestling stage on pairs nesting on tes comparadoscon los que han sido observadosen inthe ground. stalacioneshumanas en la misma regi6n de estudio.En In general, breeding parameters of the Lesser Kestrel el 75% de los nidos se ha criado con 6xito al menos un colony on the ground were similar to that of other pop- pollo, con un promedio de 2.0 pollos pot pare,ja reprodulations, except for clutch size,which was lower than in uctora. Cinco parejas han sido localizadasen gallineros other studies.Variations in clutch size and breeding suc- usando los mismos nidos de las gallinas y tres de ellos cesswere also reported for other Lesser Kestrel popula- charon pollos con 6xito. Una puesta rue encontrada en nons (Negro and Hiraldo 1993, Tella et al. 1996) and un cubo de plftsticoy otra en un barril de aceite. [Traducci6n de los autores] may be related to changesin food availabilityfrom yr to yr or to habitat type (Newton 1979, Negro et al. 1992, ACKNOWI,EDGMENTS Negro and Hiraldo 1993, Tella et al. 1996). The Lesser We would like to thank E. Vlachou, E. Dafos, V. Bob Kestrel that we studiedfed exclusivelyon insects,mainly cricketsand grasshoppers(Orthoptera), the populations zorlos, T. Papadopoulos,and D. Tsalagasfor their assistance with the fieldwork. We are also grateful to the 4th of which fluctuate fkom yr to yr in the study area. The Hunting Federation of Sterea Hellas and Municipal Enlow clutch size of Lesser Kestrels that either nested on terprise and EcotouristCenter of Dadia, which have supthe ground or on the buildings in 1999, suggeststhat the ported this research financially. We also thank Drs. JJ period of study was a yr of food shortage,compared to Negro, D. Serrano, and an anonymous referee who rethat recorded for the same study area in 2000 (Bakal- viewed and greatly improved this manuscript. oudis et al. 2000). Finally, the percentage of unhatched LITERATURE CITED eggswas low and similar to the results of other studies (Negro et al. 1993), suggestingthat the hatching success BALFOUR, E. 1955. Kestrel nesting on the ground in Orkeither of Lesser Kestrels that nested on ground or on ney. Bird Notes26:245-2,53. buildings in Megalo Monastiri village wasnot negatively BAKALOUDIS,D., C. rEACHOS, AND E. CHATZINIKOS. 2000. affected by contamination.However,the widespreaduse Breeding successin the LesserKestrelFalconaumannz of pesticidesin intensive cultivation could be a possible in Thessaly,central Greece. Conference for Birds of reason for adult deaths or for low feeding rates (i.e., the Prey and Owls, 22-26 November 2000. Mikulov, Czech observed mortality of chicks due to starvation) as these Republic. could affkct prey populationsnegativelyduring the late BIBER,J.P. 1996. International action plan ibr the Lesser

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Kestrel (Falconaumanni). Pages 191-203 in B. Heredia, L. Rose, and M. Painter lEDs.l, Globally threatened birds in Europe. Council of Europe Publishing, Berlin, Germany. CRAMP, S. AND K.E.L. SIMMONS. 1980. The birds of the

western palearctic. Vol. 2. Hawks to bustards. Oxford Univ. Press, Oxford, U.K.

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breeding successin the LesserKestrel Falconaumanm Bird Study40:115-119.

NEWTON, I. 1979.Populationecologyofraptors.T. & A D. Poyser,London, U.K. PIECHOCKI, R. 1982. Der Turmfalke. Ziemsen'Verlag,W•ttenberg, Germany. SEAGO, MJ. 1967. The birds of Norfolk.Jarrold & Son,

Norwich, U.K. DONAZAR, J.A., JJ. NEGRO,ANDF. HImDO. 1993. ForagD., J.L. TELLA,M.G. FORERO, ANDJ.A.DON3•ZAR ing habitat selection,land-use changesand popula- SERRANO, 2001. Factors affecting breeding dispersal in the faction decline in the LesserKestrelFalconaumanni.J. ultatively colonial Lesser Kestrel: individual experiAppliedEcol.30:515-522. ence rs. conspecificcues.J. AnimalEcol.70:568-578. FORERO,M.G., J.L. TELLA,J.A. DONAZAR, ^ND F. HIRALDO. K. 1087.Assessing raptor reproductivesuccess 1996. Can interspecific competition and nest site STEENHOF, and productivity. Pages 157-170 in B.A.G. Pendleton, availabilityexplain the decreaseof LesserKestrelFalco B.A. Millsap, K.W. Cline, and D.M. Bird [EDS.],Rapnaumannipopulations?Biol. Conserr.78:289-293. tor managementtechniquesmanual. Nat. Wildl. Fed, HAGEMEIJER, WJ.M. ANDMJ. BLAIR.1997. The EBCC AtWashington, DC U.S.A. las of European Breeding Birds: Their Distribution TELLA,J., F. HIRALDO,J. DONAZAR, ANDj. NEGRO.1996. and Abundance. T. & A.D. Poyser,London, U.K. Costsand benefits of urban nesting in the LesserKesHALl.MANN, B. 1996. LesserKestrelsurvey:Thessaly1995. trel. Pages53-60 in D. Bird, D. Varland,andJ.J.Negro Report to the Hellenic OrnithologicalSociety,TheslEDS.l, Raptorsin human landscapes.AcademicPress saloniki, Greece.

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NEGRO,JJ., J.A. DONXZAR, ANDF. HIRALDO.1992. Kleptoparasitism and cannibalism in a colony of Lesser Kestrels(Falconaumanni).J. RaptorRes.26:225-228. , J.A. DONXZAR,F. HIRALDO,m. HERNANDEZ,AND M. FERNXNDEZ. 1993. Organochlorineand heavymetal contamination in non-viable eggs and its relation to breeding successin a Spanishpopulation of Lesser Kestrels (Falco naumanni). Environ. Pollut. 82:201-205. , AND F. HIRALDO. 1993. Nest-site selection

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M.G. FORERO,F. HIRALDO,ANDJ.A. DONX7AR 1998.

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and European agriculturalpoliciesas identified by habitat use analysis.Conserr.Biol. 12:593-604. VILL•GE,A. 1990. The kestrel.T. & A.D. Poyser,London, U.K.

Received 29 January 2003; accepted 29 December 2003 AssociateEditor:Juan josfi Negro

J RaptorRes.38(2):163-168 ¸ 2004 The Raptor Research Foundation, Inc. FAT STORES OF MIGRANT SHARP-SHINNED AND COOPER'S HAWKS IN NEW MEXICO

JOHNP. DELONG • HawkWatchPnternational, Inc., 1800 SouthWestTemple, Suite226, SaltLakeCity,UT 84115 U.S.A.andDepartment of Biology,UtahStateUniversity, 5305 University Blvd., Logan,UT 84322 U.S.A. STEPHEN W. HOFFMAN 2

HawkWatchInternational,Inc., 1800 SouthWestTemple,Suite226, SaltLate City,UT 84115 U.S.A. KEY WORDS: Cooper's Hawk; Accipiter cooperii; SharpBirds use stored fats to supply energy during times shinnedHawk;Accipiter striatus;avian energetics; migration; when foraging is limited or not possible (King 1970, fat scores; fat stores. Blem 1980). During migration, stored fat allowsbirds to make uninterrupted flights between places and times when foraging can occur and fat storescan be replen• Presentaddress:2314 HollywoodAve. NW, Albuquer- ished (King 1970, Blem 1980). The amount of fat that que, NM 87104 U.S.A.; e-mail address:jpdelong@ birds store during and leading up to migration varies comcast.net widely (Blem 1980). Fat storesranged from 4% of total 2 Presentaddress:AudubonPennsylvania, 100 Wildwood body massin Common Buzzards (Buteobuteovulpinus) Way,Harrisburg,PA 17110 U.S.A. migrating through Israel (Gorney and Yom-Tov1994) to