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P. Major (p + major)
Selected AbstractsPair bond and breeding success in Blue Tits Parus caeruleus and Great Tits Parus majorIBIS, Issue 1 2005MIRIAM PAMPUS Data from 939 nests of the Blue Tit Parus caeruleus and 1008 nests of the Great Tit P. major from nestboxes provided in superabundance in mixed forest study sites between 1976 and 2001 were analysed to examine the effects of mate retention on breeding success and the relationship between mate fidelity and site fidelity. Most birds retained their former partner (76% in Great Tits and 65% in Blue Tits). The probability of a pair divorcing was affected by male age in Great Tits, divorce being more likely in pairs with first-year males. Great Tit pairs breeding together for a second season bred earlier, but had no higher breeding success than pairs breeding together for the first time. In Blue Tits laying date and start of incubation tended to be earlier in pairs breeding together for a second season, but hatching and fledging dates were not earlier than in other pairs. Great Tit pairs breeding together for two consecutive seasons bred earlier in the second season than in the first, but breeding success did not differ significantly between years. In both species, breeding performance did not differ between pairs that divorced after a season and pairs that stayed together. Thus breeding success did not determine whether a pair divorced or bred together again. Neither Blue Tits nor Great Tits improved their breeding performance through divorce. Blue Tit females even had fewer fledglings in the year after divorce than in the year before. Mate retention affected breeding site fidelity. Blue Tit females had greater breeding dispersal distances between consecutive years when re-mating than when breeding again with the same mate. In Great Tits both males and females dispersed more when re-mating than when retaining the former partner, suggesting that mate retention increased the chance of retaining the breeding site. In both species, breeding dispersal distances did not differ between pairs that divorced and pairs in which one mate disappeared. Because no major advantage of mate retention was evident, we suggest that mate retention evolved under different conditions than those found in study sites with high breeding densities and a superabundance of artificial nesting sites. [source] Daily patterns of body mass gain in four species of small wintering birdsJOURNAL OF AVIAN BIOLOGY, Issue 3 2002Kristjan Lilliendahl Theoretically, the trajectories describing the daily accumulation of body reserves are expected to differ between bird species in relation to whether or not they hoard food. To carry reserves on the body may be costly and hoarding species can be expected to hoard food early in the day when light and retrieve it in the afternoon, with a concomitant rapid increase in body mass. Also, the increased food predictability resulting from being able to consume hoarded food late in the day should lead to a relatively faster gain in body reserves in the afternoon in hoarding species compared to non-hoarders. Non-hoarders may have to hedge against possible afternoon losses of foraging opportunities by accumulating more reserves early in the day. In this study the daily patterns of body mass gain in four small bird species resident during winter in Scandinavia are described. Individually known birds were trained to come to a permanent feeder and their body masses were recorded every hour throughout the day with a remote-controlled balance. The hoarding willow tit Parus montanus, marsh tit P. palustris and European nuthatch Sitta europaea all displayed the most rapid gain in body mass in the early hours of the day. After the initial burst in the morning, reserves were accumulated at a roughly constant rate for the remainder of the day. In contrast, the non-hoarding great tit P. major apparently gained body reserves at a more even rate. The daily pattern of body mass gain found in the hoarding species differs from prevailing theoretical predictions, whereas the pattern in the non-hoarding great tit is in a better agreement with theory, from which this pattern has been predicted repeatedly. [source] Polymorphic microsatellite loci in Plantago lanceolataMOLECULAR ECOLOGY RESOURCES, Issue 1 2003Marie L. Hale Abstract The genus Plantago is particularly interesting for evolutionary studies because of its wide range of mating systems. We have developed primers for five highly polymorphic microsatellite loci isolated from P. lanceolata. All five loci amplified and were polymorphic in the two populations examined, Lowsteads Beach in the United Kingdom and Duke in the United States. These new markers will allow a comparison of population structure between the outcrossing species P. lanceolata, and the highly selfing species P. major. [source] What constitutes optical warning signals of ladybirds (Coleoptera: Coccinellidae) towards bird predators: colour, pattern or general look?BIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 1 2009MICHAELA DOLENSKÁ Most ladybirds (Coleoptera: Coccinellidae) possess chemical protection against predators and signal its presence by less or more conspicuous coloration, which can be considered as a warning. Most ladybirds possess a dotted pattern, althougn the number, shape, and size of the spots, as well as their colour, varies considerably. Almost all ladybirds have a characteristic general appearance (body shape). We considered these traits to be used in ladybird recognition by avian predators. In the present study, we compared the reactions of avian predators (Parus major) caught in the wild, to four differently coloured ladybird beetles (Coccinella septempunctata, Exochomus quadripustulatus, Subcoccinella vigintiquatuorpunctata, and Cynegetis impunctata) and two artificial modifications of C. septempunctata; the first was deprived of their elytral spotted pattern by painting it brown, the other had their elytra removed (i.e. altering their general ladybird appearance). Ladybirds with a spotted pattern were attacked less frequently than unspotted ones. Ladybirds with removed elytra were attacked much more often than any ladybird with a preserved general appearance. The results obtained in the present study suggest the high importance of the spotted pattern as well as general appearance in the ladybird recognition process. Additional experiments with naïve birds (hand-reared P. major) demonstrated the innateness of the aversion to two differently spotted ladybird species (C. septempunctata and Scymnus frontalis). © 2009 The Linnean Society of London, Biological Journal of the Linnean Society, 2009, 98, 234,242. [source] | |||||||||||||||||||