Research Article |
Corresponding author: Mercival R. Francisco ( mercival@ufscar.br ) Academic editor: Luis Fabio Silveira
© 2017 Daniel Fernandes Perrella, Paulo V. Davanço, Leonardo S. Oliveira, Livia M.S. Sousa, Mercival R. Francisco.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Perrella DF, Davanço PV, Oliveira LS, Sousa LMS, Francisco MR (2017) Reproductive aspects of the Purple-throated Euphonia, Euphonia chlorotica (Aves: Fringillidae) in southeastern Brazil, and first record of the species nesting inside a vespiary. Zoologia 34: 1-7. https://doi.org/10.3897/zoologia.34.e19989
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Despite the fact that E. chlorotica (Linnaeus, 1766) is common and widely distributed in South America, the reproductive aspects of the species are poorly documented. Here we present data on 18 active nests found from August to February, between 2007 and 2012. Nests were globular with a lateral entrance, and measured 97.9 ± 14.4 mm in outside height, 110.6 ± 11.6 mm in outside diameter, and were 4.88 ± 2.09 m above ground. They were often supported from bellow and were composed mainly of tiny dry leafs and leaflets, fine petioles, and plumed seeds, all compacted with spider web silk. Eggs were laid on consecutive days or with one day interval, and clutch size varied from 1–3 eggs (2.1 ± 0.6, n = 9 nests). Only females incubated the eggs, but both sexes were involved in nest construction and nestling attendance at similar rates. Incubation and nestling periods were 14 and 21 days, respectively, and overall nest survival probability was 5%. A vespiary used for nesting was not occupied by wasps and nest material was deposited only to form the incubatory chamber. Although nesting near wasps or bees is a widespread strategy among birds in general, nesting inside the nests of social insects is a poorly documented behavior.
Birds, breeding biology, nesting behavior, Euphoniinae , wasps
Euphonias are small and conspicuous arboreal passerines, comprising 27 species that are restricted to the Neotropics (
Many behavioral and ecological aspects of the Euphonias, including reproductive biology, remain poorly documented. The nests of twenty of the currently recognized species are known, and egg characteristics have been described for 15 species. Information on nest construction and parental care is available, in varying levels of detail, for 14 species, whereas incubation, and nestling periods are known for only five and four species, respectively (
Euphonia chlorotica (Linnaeus, 1766) is widely distributed in South America, occurring in most of Brazil, Guianas, and Paraguay, and in parts of Colombia, Venezuela, Peru, Bolivia, and Argentina. It inhabits forest borders, clearings, Cerrado, Caatinga (
Our specific goals in this paper were: 1) to provide supplemental information on nest, eggs, and nestling characteristics, clutch size, and incubation period; 2) to present for the first time information on nest measurements, nesting phenology, duration of the breeding season, nesting success, partitioning of parental activities, and the first nestling period, and 3) to provide the first report of a nest constructed inside a vespiary.
Observations were conducted at the campus of Faculdade de Engenharia de Sorocaba (10.5 ha), Sorocaba, state of São Paulo, southeastern Brazil (23°28’S, 47°25’W), and at an adjacent smaller area (2 ha) of Cerrado sensu stricto, which was maintained within the urbanized area to protect a small and well-preserved stream. The campus presents extensive laws and gardens, with exotic trees, such as Pinus sp., Eucalyptus sp., Mangifera sp., and Grevillea robusta A. Cunn. ex R. Br., and also native trees typical of the Cerrado, with buildings and streets occupying about 30% of the area. The elevation is ~ 580 m asl., and the climate is classified as Cfa according to Koppen-Geiger (
Nests were routinely searched by walking along the whole area two to three times per week, from August to March, during three breeding seasons: 2007/2008, 2008/2009, and 2009/2010. Random searches were also performed in 2010/2011, and 2011/2012. Nests were found by following adults carrying material for nest construction, or delivering food to the nestlings (
The incubation period was considered from the first day of incubation to the day before hatching, and nestling period from the day of hatching to the day before fledging (
We considered nest predation when eggs or nestlings disappeared from a nest before fledging age, and abandonment when adults were no longer seen near a nest for at least three days. We considered a success when young being fed outside a nest were observed. The probability of nest survival for the whole nesting cycle was estimated following the method proposed by
We found 18 active nests during five breeding seasons: six in 2007/2008, five in 2008/2009, three in 2009/2010, two in 2010/2011, and two in 2011/2012. The earliest nesting activity was observed on 22 August 2007 (a nest in construction stage), and the latest nestlings were observed on 7 February 2009. Most breeding activities in the first three of these seasons occurred from September to November (Fig.
Nests were globular, but sometimes laterally flattened to adapt to the supporting branches. Nest wall was composed mainly of tiny dry leaves and leaflets, fine petioles, and plumed seeds, all highly compacted with a great amount of spider web silk. Pine needles and a few small stripes of dry grass were also found in some nests. Large dry leaves could be present, and all nests were dark brown externally (Fig.
Nest, eggs and nestlings of the Purple-throated Euphonia. (2) A typical nest, globular with a lateral entrance, made of dry vegetal material kept together with spider web silk. (3) Partial view of the head of a female sitting in the incubatory chamber of an atypical nest constructed inside a vespiary. (4) Eggs are typically pyriform, with brownish marks that may be more or less concentrated around the large pole. (5) Older nestlings beg for food at nest entrance, showing their red mouth lining and white oral flanges to their mother.
Notably, in 2010 a female was found incubating two eggs in a nest constructed inside an abandoned nest of unidentified wasps. The vespiary was hung from a horizontal branch of G. robusta and it was very similar in size, shape (globular), and color to the nests of Purple-throated Euphonias (Fig.
During nest construction, both males and females carried and deposited nest materials, and both were observed performing body movements to shape the incubatory chamber. In 16 hours of observation at nine nests, females brought nest material 1 to 21 times per hour, and males 0 to 14 times per hour, but the number of visits did not differ significantly between sexes (females 6.50 ± 5.09 times/hour, males 4.44 ± 4.15 times/hour, U = 94, p = 0.2). Notably, in 18% of the visits adults were observed carrying spider web stripes in their beaks that could be much longer than their own bodies (i.e. 15 cm), or they carried tufts of this material wrapped in the breast and belly. Clutch sizes were 1 (n = 1), 2 (n = 6) or 3 eggs (n = 2) (2.1 ± 0.6). Eggs were pyriform, with white background color, and dark and light brown blotches and spots, that could be round or elongated. These markings could be concentrated in the large end, or they could form a wreath near the large pole (Fig.
In three nests, eggs were laid on consecutive days, and in one nest with one day interval. In these nests, incubation started the day the last egg was laid. In another nest in which only one egg was laid, incubation started two days later. Incubation period was 14 days (n = 2 eggs from one nest). In 16 hours of observation in seven nests, only females were recorded incubating the eggs. Average time spent incubating was 28.27 ± 17.34 min per hour (range = 0–57.57), females left the nests 1.2 ± 0.75 times per hour (range = 0–2), and incubation recesses lasted 11.55 ± 12.95 min (range = 0.87–60).
Hatching was synchronous (n = 2 nests) and nestling period was 21 days (n = 2 young from one nest). Hatchling skin was dark red with sparse gray down, and nestling presented bright red mouth lining and white swollen flanges (Fig.
The nesting season in our study area matched most of the records of active nests of the Purple-throated Euphonia from other localities, i.e. one nest recorded in late November in Paraguay (
Nest shape followed the general pattern found for other Euphoniinae, but nest materials used by the Purple-throated Euphonia have been only superficially described so far, impeding detailed comparisons with other regions. However, the use of materials of the supporting plants, also reported by other authors, may be an important source of variation in nest composition. Although we report the use of a spider web for the first time, we believe that this material may have been used also in the previously described nests, as it seemed to be an indispensable component to construct a globular structure using such small vegetal materials as those reported here. Although
The presence of nests among the leaves of a bromeliad (
The clutch sizes of Purple-throated Euphonias were similar to those reported by other authors, being three eggs in the nest found by De La Peña (
Although our data on incubation and nestling periods are based on a single nest, together with the incubation period of one egg provided by
Many bird species can benefit from reproducing in anthropic habitats, where nest survival can be higher due to the increased protection provided by man-made structures, or due to the absence of certain nest predators (
We are grateful to the Faculdade de Engenharia de Sorocaba (FACENS) for authorizing field work at the campus. PV Davanço received a fellowship from Universidade Federal de São Carlos (PIADRD programe), and LS Oliveira was supported by Conselho Nacional de Desenvolvimento Científico e Tecnológico (PIBIC/CNPq). We also thank D.C. Silva for assistance in the preparation of the images. This study was part of a major project on bird reproductive biology that was approved by IBAMA/CEMAVE (#3023/1 and #3023/2).