Open AccessThe geographical distribution of populations of the large‐billed subspecies of reed bunting matches that of its main winter food
Author(s) -
MATESSI GIULIANO,
GRIGGIO MATTEO,
PILASTRO ANDREA
Publication year - 2002
Publication title -
biological journal of the linnean society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.906
H-Index - 112
eISSN - 1095-8312
pISSN - 0024-4066
DOI - 10.1046/j.1095-8312.2002.00003.x
Subject(s) - subspecies , biology , bunting , ecology , reproductive isolation , breed , population , distribution (mathematics) , zoology , demography , mathematical analysis , mathematics , sociology
We investigated the effects of resource distribution on the population structure and distribution of a polytypic bird species. We compared the presence of insect remains (mainly dormant larvae) in the winter diet of two reed bunting subspecies, small billed E. s. schoeniclus and large billed E. s. intermedia and studied the distribution of this resource within reed ( Phragmites sp.) stems in seven north Italian localities where the two subspecies breed (three schoeniclus and four intermedia populations). We also tested if the distributions of winter insect resources and breeding populations of the large bill subspecies overlapped. The distribution of the larvae in reed stems matched closely the distribution of large billed breeding populations. The winter diets of the two subspecies were significantly different in terms of frequency of insect remains. These results, when compared to theoretical models of para‐patric distribution, suggest that the two subspecies may be subject to ecological (vicariant) selection maintaining their reproductive isolation. © 2002 The Linnean Society of London, Biological Journal of the Linnean Society , 2002, 75 , 21–26.