Birds and Berries: A study of an ecological interaction

Description

The book’s subtitle – A study of an ecological interaction – properly reflects the author’s theme but may tend to hide the fact that the relationships between birds and berries can be much more than the simple, mutually advantageous systems (‘eat my fruits, spread my seeds’) they may seem at first to be. Therein lies the core of the book – the less obvious intricacies and implications of plant/ bird associations, the coevolution of species in some cases and the adaptations of a species (bird or plant) to further its own advantage. To complicate the scene, too, there are the ‘exploiters’, the pulp-predators and seed-predators that feed at the plant’s expense. In Part 1 of the book the authors provide accounts by species of the trees and shrubs they observed over many years in their study area of southern England; similarly, Part 2 records the bird species they watched feeding, or attempting to feed, or preventing other birds from feeding, on the fruits. Part 3 ranges widely and is not confined to Britain and Europe. It investigates the strategies and adaptations evolved and employed by plants to ensure their success, and their attempts at defence against the bird ‘predators’. It looks at the birds themselves, their foraging techniques and fruit preferences, the limitations of a fruit diet and adaptations to it, the time and energy budgets of fruit-eaters and, finally, the intriguing question of coevolution of plants and birds. This thought-provoking text offers many insights not generally perceived by ornithologist or botanist and is illustrated in masterly fashion by John Busby’s lively drawings. Jacket paintings by John Busby Cover Contents Introduction Acknowledgements 1 THE FRUITS The seasonal pattern of fruiting Holly Ilex aquifolium Yew Taxus baccata Ivy Hedera helix Mistletoe Viscum album Dog rose Rosa canina Other roses Haws Crataegus spp Rowan Sorbus aucuparia Whitebeam Sorbus aria Wild service tree Sorbus torminalis Wild cherry Prunus avium Bird cherry Prunus padus Blackthorn Prunus spinosa Blackberry Rubus fruticosus Wild raspberry Rubus idaeus Crab-apple Malus sylvestris Elder Sambucus nigra Wayfaring tree Viburnum lantana Guelder rose Viburnum opulus Honeysuckles Lonicera spp Dogwood Cornus sanguinea Privet Ligustrum vulgare Buckthorn Rhamnus catharticus Spindle Euonymus europaeus Wild currant Ribes rubrum Wild gooseberry Ribes uva-crispi Woody nightshade Solanum dulcamara Black nightshade Solanum nigrum Deadly nightshade Atropa belladonna White bryony Bryonia dioica Black bryony Tamus communis Spurge laurel Daphne laureola Mezereon Daphne mezereum Juniper Juniperus communis Lords and ladies Arum maculatum Some minor fruits Introduced and cultivated plants 2 THE FRUIT-EATERS Blackbird Turdus merula Song Thrush Turdus philomelos Mistle Thrush Turdus viscivorus Fieldfare Turdus pilaris Redwing Turdus iliaClis Robin Erithacus rubecula Blackcap Sylvia atricapilla Other warblers and flycatchers Starling Sturnus vulgaris The Corvidae Occasional or scarce fruit-eaters Waxwing Bombycilla garrulus Wood pigeon Columba palumbus Seed-predators and pul p-predators The finches The sparrows The tits 3 INTERPRETATION Physical characteristics of fruits: size and seed burden The colour and taste of fruits Competition between plants for dispersers Adaptation of fruiting seasons and fruit quahty to changing bird populations Seed-predators and the plants' defences Physical limitations to fruit-eating Adaptations for a fruit diet Fruit preferences Foraging strategies of fruit-eaters Fruit as a component of the total diet Time and energy budgets for fruit-eaters The question of coevolution Appendices I Plants with fleshy fruits native to England and Wales 2 Design components of native hird-dispersed fruits, southern England 3 Design components of some introduced and cultivar bird-dispersed fruits, southern England 4 Nutritive values of some bird-dispersed fruits, southern England 5 Monthly totals of timed watches at wild fruits, southern England 1980- 85 References Index A B C D E F G H I J K L M N O P Q R S T U V W Y Z