Fruit-Handling Techniques of Rose-Ringed Parakeets Psittacula Krameri Feeding on Alangium Salviifolium (Linn.) Fruits in Sriharikota Island, Southern India
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Short Notes 75 Fruit-handling techniques of Rose-ringed Parakeets Psittacula krameri feeding on Alangium salviifolium (Linn.) fruits in Sriharikota Island, southern India J. Patrick David, B. Senthil Murugan & Ranjit Manakadan David, J. P., Murugan, B. S., & Manakadan, R., 2010. Fruit-handling techniques of Rose-ringed Parakeets Psittacula krameri feeding on Alangium salviifolium (Linn.) fruits in Sriharikota Island, southern India. Indian BIRDS 6 (3): 75–77. J. Patrick David, Ph. D Student, Hornbill House, Bombay Natural History Society, Shaheed Bhagat Singh Marg, Mumbai 400001, Maharashtra, India. Present address: Ashoka Trust for Research in Ecology and the Environment, Royal Enclave, Srirampura, Jakkur Post, Bangalore 560064, Karnataka, India. Email: [email protected]. (Corresponding author). B. Senthil Murugan, Senior Research Fellow, Hornbill House, Bombay Natural History Society, Shaheed Bhagat Singh Marg, Mumbai 400001, Maharashtra, India. Email: [email protected]. Ranjit Manakadan, Assistant Director, Hornbill House, Bombay Natural History Society, Shaheed Bhagat Singh Marg, Mumbai 400001, Maharashtra, India. Email: [email protected]. Manuscript received on 9 March 2009. Introduction (Figs. 1–2). The seed is enclosed in a hard, stony, brown seed The Rose-ringed Parakeet Psittacula krameri is a widespread coat, and ranges in diameter from 8.8 to 10.8 mm. Between the resident in the Indian Subcontinent, inhabiting forests, gardens, seed and the fruit coat there is a layer of white slimy pulp. The cultivations, towns, and cities (Ali & Ripley 1987; Rasmussen & tree bears fruit from late mid-April to early August, and produces Anderton 2005). It is highly destructive to crops and orchards, 1,000–1,500 fruits/tree. gnawing and wasting far more food than it actually eats (Ali 2002). Many studies have documented this destructive Methods feeding behaviour and quantified the extent of seed damage We observed a cluster of three trees, with overlapping branches, in agricultural landscapes (Simwat & Sidhu 1974; Sandhu & to collect data on number of diurnal visitors to fruiting trees, Dhindsa 1982; Malhi & Brar 1985; Saini et al. 1994). But no and their feeding behaviour in May 2006. Tree watch (extended study has quantified the extent of seed waste (either dropping observation on fruiting trees) was done from 0600 to 0900 hrs or consuming seeds) by the Rose-ringed Parakeet in the wild. on one day of the fruiting period. Additional information was This short note describes the fruit-handling behaviour of the gathered during phenology work, done to assess the influence Rose-ringed Parakeet while feeding on Alangium salviifolium of rainfall on fleshy-fruit production, and while monitoring plots (Alangiaceae) fruits (Fig. 1) in Sriharikota Island, Andhra Pradesh, below Alangium fruiting trees. To quantify the seeds dropped India, and the probable implications for seedling recruitment. by Rose-ringed Parakeets, Fig. 1. Alangium salviifolium seeds and 2 A. salviifolium is a small deciduous tree, shrub, or straggler. It four 1 m plots were laid on pulp (left), and opened fruit coat (right) is found in the drier parts of India, Sri Lanka, and Myanmar, with the ground below the three several medicinal uses—treatment of bites of rabbits, rats, and fruiting trees. The plots dogs, analgesic and anti-inflammatory activities, antimicrobial were monitored once in potential, anti-arthritic activity of stem barks, etc., (Anon. 1948). three days throughout the In Sriharikota, where the vegetation has been classified as Tropical fruiting period, May–June. Dry Evergreen forest (Champion & Seth 1968), A. salviifolium We recorded the number of is found only in the central and southern parts of the island, fallen seeds, ripe and unripe along its periphery. It is a rare tree, usually growing in clusters of fruits, and those without David Patrick 2–4, and is 6–7 m tall. It produces medium-sized, pink, globose (eaten) seeds. The work fruits ranging in diameter from 14.7–16.6 mm (N=10 fruits) was part of a larger study 76 Indian BIRDS Vol. 6 No. 3 (Publ. 7th August 2010) on fruit–frugivore interactions in Sriharikota carried out between In addition to the above factors which could affect seed November 2004 and May 2008. dispersal of A. salviifolium, there are no known seed dispersers for this species, the Red-whiskered bulbul Pycnonotus jocosus Results and White-browed Bulbul Pycnonotus luteolus (which are the common avian frugivores in Sriharikota) were not recorded Visitors to the fruiting trees feeding on these fruits. Also, the seeds of A. salviifolium were During a three-hour observation period on fruiting Alangium not recorded in the droppings of Bonnet Macaque, Golden Jackal trees, Rose-ringed Parakeets made five visits, and bonnet and Small Indian Civet, which are the major mammalian seed macaque Macaca radiata nine. Only during the first half of the dispersers in Sriharikota (David et al. 2008). We noticed full fruits tree watch period both these species were recorded, during the on the ground away from the fruiting tree, probably carried by second half there were no visitors. During other visits to the the Bonnet Macaque in their hand. In this way seeds might be forest (to monitor plots, and estimate fruit abundance), only dispersed, but the number of seeds moved away from the parent Rose-ringed Parakeets were observed feeding on the fruits. Bat- tree in this manner will be substantially low, considering the eaten fruits were not recorded. large quantity of seeds dropped below the fruiting tree. Bonnet Macaques were also recorded feeding on A. salviifolium fruits in Fruit-handling techniques Elephanta Island (Kuruvilla 1980). Rodents on the ground could Rose-ringed Parakeets opened the fruit from the end where the also have removed seeds. Secondary seed dispersal by rodents fruit was attached to the stalk. While feeding, it used its legs to was not taken into consideration during this study. bring the fruit closer to its beak or the fruit was handled in its This seems to be a case where plant recruitment into the original position. The parakeets were oblivious to our presence ecosystem is crippled by a combination of massive seed drop, under the feeding tree and continued to feed. Several seeds seed predation and absence of dispersal agents. The dispersal were dropped in our presence. It reached the seed after making system described above is specific only to the study area and a small opening in the delicate pericarp. Both ripe and unripe does not apply to the entire geographic range in which the plant fruits were handled. In the unripe fruit the seeds were not fully is distributed. Any effect on plant recruitment will only affect the formed and they were soft and easy to eat, but in ripe fruits the local population and will not threaten the existence of the species seed is protected by a hard seed coat. Judging from the large as such. This study suggests that investigations into frugivory by number of full unripe fruits collected in the plots (Table 1) it parakeets is essential to understand local plant demography. seems that ripe fruits were handled more than unripe fruits and the parakeets should have been trying to eat the pulp. If they Acknowledgements wanted to eat the seeds they would have attacked more unripe The authors wish to thank the Indian Space Research Organisation fruits and parakeets rarely visited the trees when unripe fruits (ISRO) for sponsoring the project on Plant–Animal interactions, which were available. In either their search for the immature fruits or the led to this interesting short study; especially the late Prof. Satish Dhawan, pulp the parakeets dropped many seeds below the fruiting tree. former Chariman, ISRO, whose love for the wilderness was instrumental in the projects being conceptualized, and sanctioned. We also wish to Table 1: Number of seeds and fruits collected in four 1 m2 plots thank ISRO for providing logistical support for the entire tenure of the below a cluster of 3 fruiting trees across the season project. Our Yanadi field assistant Mr Manikala Parandamaiah was of im- Full fruit mense help during data collection. We wish to thank T. Ganesh, Fellow, Fruit coat Full seed Ripe Unripe ATREE, for his comments on an earlier draft of the manuscript. The help Plot 1 126 71 10 28 and guidance of S. Sivakumar, and V. Kannan, our colleagues in BNHS is Plot 2 293 213 21 108 also fully appreciated. Plot 3 273 301 16 139 Plot 4 169 211 18 30 References Total 983 768 65 305 Ali, S., 2002. The book of Indian birds. 13th (Revised) ed. Daniel, J. C. (ed.) Mumbai: Bombay Natural History Society & Oxford University Press. Discussion Ali, S., & Ripley, S. D., 1987. Compact handbook of the birds of India and In general, members of the family Psittacidae are pre-dispersal Pakistan together with those of Bangladesh, Nepal, Bhutan and Sri seed predators and seed droppers (Galetti 1993; Kristosch Lanka. 2nd ed. Delhi: Oxford University Press. 2001; Francisco et al. 2002). This study indicates that they Anonymous. 1948. Wealth of India: dictionary of Indian raw materi- dropped more seeds than they predated. While seed predation als and industrial products. New Delhi: CSIR, Government of India Press. instantly kills the seeds, dropping seeds below the fruiting tree Champion, H. G., & Seth, S. K., 1968. A revised survey of forest types of in high densities exposes the seeds and seedlings to attacks by India. New Delhi: Government of India Press. insects and rodents (Janzen 1971; Pizo 1997). Even if the seeds David, P., Murugan, S. B., & Manakadan, R., 2008. Plant–animal inter- escape predation on the ground and germinate, there will be relationships with special reference to food plants of birds and heavy competition among seedlings to survive below the fruiting mammals. Pp. 6-52. In: Investigations into some ecological aspects tree and the chances of successful establishment are thus of Sriharikota Island.