The nest, eggs and nestlings of Grey-chinned Hermit Phaethornis ...

Cotinga 35The nest, eggs and nestlingsof Grey-chinned HermitPhaethornis griseogularisPhaethornis is one of the largestgenera of hummingbirds, with 26species distributed throughouttropical America 6 . The nests andgeneral breeding biology for mostspecies have been studied, and thegenus is well known for its lekkingbehaviour 6 . The reproduction ofGrey-chinned Hermit Phaethornisgriseogularis, however, is almostcompletely unstudied. Thespecies ranges from Colombiaand Venezuela to northern Peru,at elevations of 600–2,000 m 5,6 .Based on the distributions givenby Schuchmann 6 and Ridgely &Greenfield 5 , the nest we studiedbelonged to P. g. porcullae,which taxon is restricted to theTumbesian region of south-westEcuador and north-west Peru.Gould 2 , in the plate accompanyinghis discussion of this species,figured two nests, drawn fromexamples in his own collection.Although Gould 2 provided nofurther details or locality datafor these nests, they are figuredwith the nominate subspecies,and thus probably belong to P. g.griseogularis. Thus, although thenest of Grey-chinned Hermit haspreviously been illustrated, this isthe first formal description.On 10 February 2010 we founda nest of P. griseogularis at theJorupe Reserve, near Macará,prov. Loja, south-west Ecuador(04°23’S 79°57’W; 600 m). At08h45 we flushed an adult froma nest which contained twoimmaculate white eggs (Fig. 1)that measured 12.27 × 8.05 mmand 12.15 × 7.95 mm, and weighed0.40 and 0.39 g, respectively. At16h00 on 13 February, the secondegg described above had hatched,but we were unable to detect anypips in the shell of the other egg.The single nestling weighed 0.37g, indicating that it had hatchedonly shortly before our arrival. Itwas pink-skinned, darker dorsally,and bore 11 pairs of beige-colourednatal plumes on its back. At 06h45the following morning the otheregg remained unhatched, buton our return that day at 14h00the nest contained two nestlings.Short CommunicationsFigure 1. Eggs of Grey-chinned Hermit Phaethornis griseogularis porcullae, prov. Loja,Ecuador, 10 February 2010 (Harold F. Greeney)Figure 2. Nestlings of Grey-chinned Hermit Phaethornis griseogularis porcullae fiveand six days old, prov. Loja, Ecuador, 19 February 2010 (Harold F. Greeney)At this time the newly hatchednestling weighed 0.37 g and theone which was now one day old0.48 g. We weighed them only oncemore, on 17 February at 06h45.While we were unable to identifythe nestlings individually, onewas significantly heavier (0.86 g),and we presume the other (0.65 g)to have been the younger sibling.By six days of age the nestlingswere porcupine-like, with contourfeather pins emerged from the skin(Fig. 2). These pin feathers beganbreaking their sheaths by dayseven or eight, and the nestlingsappeared well feathered by day17 or 18. The nest was visitedevery two days and, on 6 Marchat 08h40, it still contained twonestlings that appeared very closeto fledging. On 7 March, at 15h00,one nestling had left the nest, butwe were unable to locate it. Thesecond nestling remained at 08h30the following day, but was gone by12h00 on 9 March. Thus, hatchingoccurred c.24 hours apart andthe nestlings fledged at least 24hours apart, possibly even closerto 48 hours. These observationsprovide a nestling period of 21–2384

Cotinga 35Figure 3. Adult Grey-chinned HermitPhaethornis griseogularis porcullaeincubating two eggs, prov. Loja,Ecuador, 12 February 2010 (Harold F.Greeney)days for P. griseogularis, similarto that reported for other smallPhaethornis 3,6–8 .In typical hermit style, the nestwas attached to the underside ofa leaf, 1.3 m above the ground(Fig. 3), at the bottom of a smallriparian area. The leaf belonged toan unknown species of Lauraceae,and measured c.28 cm long by 6.5cm wide (max. dimensions). Thenest comprised a complex mixof small bark pieces, seed down,small dried flower inflorescencesand (predominantly) green moss. Itwas bound together and attachedto the leaf with copious spiderwebs, and had a sparse innerlining of soft white seed down(Fig. 1). The front rim (furthestfrom the leaf) was c.1 cm lowerthan the portion attached to theleaf. Internally the cup measured28 mm wide by 24 mm deep atthe shallowest point. Externallythe nest was 47 mm wide by 38mm front to back (perpendicularto the axis of the leaf blade). Fromthe back rim of the nest (againstthe leaf) to the tip of the leaf itmeasured 49 mm, and 32 mmfrom the front rim. The nest hada well-formed ‘tail’ of materialdangling below the leaf, whichextended 11 cm, with an additional4 cm of sparse scraps below this.Unsurprisingly, the nestsillustrated by Gould 2 appear verysimilar to the nest described here,including having the appearanceof being composed, at leastexternally, of moss and seeddown. Similarly, the nest of P.griseogularis closely resembles,in form and attachment, thoseof other Phaethornis 6 , includingtwo well-studied species thoughtto be closely related; StripethroatedP. striigularis 4,7,8 andReddish Hermits P. ruber 1,3 . Theother two presumed relatives ofP. griseogularis, Black-throatedHermit P. atrimentalis and WhitebrowedHermit P. stuarti still lackpublished descriptions of theirnests.AcknowledgementsWe thank Field Guides Inc.,John V. & the late Ruth AnnMoore, Matt Kaplan, Tim Metz,the PBNHS, Population BiologyFoundation and Tom Walla forsupporting HFG’s field work.Members of Jocotoco Foundationand staff at Jorupe Reserve, inparticular Leonidas E. Cabrera,were instrumental in completingthis study. We thank Juan FreileShort Communicationsand an anonymous reviewer forimprovements to the manuscript.References1. Davis, T. A. W. (1958) Thedisplays and nests of threeforest hummingbirds. Ibis100: 31–39.2. Gould, J. (1861) A monographof the Trochilidae, 1. London,UK: Taylor & Francis.3. Oniki, Y. (1970) Nestingbehavior of Reddish Hermits(Phaethornis ruber) andoccurrence of wasp cells innests. Auk 87: 720–728.4. Peck, M. E. (1910) The effectof natural enemies on thenesting habits of someBritish Honduras birds.Condor 12: 53–60.5. Ridgely, R. S. & Greenfield,P. J. (2001) The birds ofEcuador. Ithaca, NY: CornellUniversity Press.6. Schuchmann, K. -L. (1999)Family Trochilidae(hummingbirds). In: delHoyo, J., Elliott, A. &Sargatal, J. (eds.) Handbookof the birds of the world, 5.Barcelona: Lynx Edicions.7. Skutch, A. F. (1951) Lifehistory of Longuemare’sHermit hummingbird. Ibis93: 180–195.8. Skutch, A. F. (1964) Lifehistories of hermithummingbirds. Auk 81: 5–25.Harold F. Greeney, IsaacLichter-Marck and Eli Lichter-MarckYanayacu Biological Station& Center for Creative Studies,Cosanga, Napo, Ecuador; c/o 721Foch & Amazonas, Quito, Ecuador.E-mail: revmmoss@yahoo.com.Received 10 October 2011; finalrevision accepted 11 August 2012;published online 10 March 201385