Search results for "Calonectris diomedea"
showing 9 items of 9 documents
First GPS-tracking of Cory’s shearwater in the Mediterranean Sea.
2010
Abstract The behaviour and ecology of seabirds such as albatrosses, petrels and shearwaters have been the subject of numerous studies, often employing the most recent technologies to track birds during their foraging trips. Until now, however, large oceanic species have been preferred for tracking studies because of the dimensions and weight of the devices available. New light-weight GPS (Global Positioning System) loggers (< 9 g) were used to track foraging trips of a medium-sized species, the Cory's shearwater, for the first time in the Mediterranean Sea. The tracks obtained showed that Mediterranean Cory's shearwaters alternatively used one of two different fishing areas. Various explana…
Sexing adult Cory's Shearwater by discriminant analysis of body measurements on Linosa Island (Sicilian Channel), Italy
2001
-Males and females of many avian species may show no plumage dimorphism, but often can be sexed by differences in body measurements. Sex determination of many Cory's Shearwaters Calonectris diomedea, was possible by multiplying bill length by bill depth. In this study, discriminant analysis of six measurements (bill length, bill depth, wing, tail, tarsus and mass) was performed on Cory's Shearwaters breeding on Linosa Island (Sicilian Channel), Italy and the efficiency of sex determination was compared with the univariate method. Results show the advantages of the discriminant functions. Bill depth is the best parameter (up to 92% correct classification), followed by mass (84% correct class…
Seabirds mated for life migrate separately to the same places: behavioural coordination or shared proximate causes?
2015
Long-term pair bonds occur in diverse animal taxa, but they are most common in birds, and can last from a few years to a lifetime. In many of these species, after the reproductive season, birds migrate to distant nonbreeding grounds where they remain for several months, and until recently, little was known about whether partners maintain contact during migration. This gap in knowledge was primarily due to past methodological difficulties in tracking long-term, large-scale movements of individuals. However, the development of new animal-borne geolocation devices has enabled researchers to track movements of individuals for a year or more. We tracked the annual migrations of both members of b…
Individual variation of persistent organic pollutants in relation to stable isotope ratios, sex, reproductive phase and oxidative status in Scopoli's…
2017
Abstract: Little is known about the accumulation of persistent organic pollutants (POPs) and its consequences for seabirds in the Mediterranean basin. We characterised the plasma contaminant profile (polychlorinated biphenyls ΣPCBs; organochlorine pesticides ΣOCPs; polybrominated diphenyl ethers ΣPBDEs) of a population of the seabird Scopoli's shearwater (Calonectris diomedea) that breeds in the southern Mediterranean (Linosa Island) and investigated (i) whether sex, stable isotope ratios (related to diet), reproductive phase (early incubation vs. late breeding season) and body mass explained variation in contaminant burden and (ii) whether they predict health-related variables. The predomi…
Biometrical and Biological Considerations on the Cory’s Shearwater Calonectris Diomedea
1986
Today the Mediterranean distribution of Cory’s Shearwaters is believed to be well known. New colonies may be discovered, but certainly the largest ones are known. Many data were published during the last ten years and we believe to have a satisfactory knowledge of their biology, though some problems, as the winter movements of each population, the first breeding age and the ratio immatures/adults are still to be examined carefully.
Olfactory foraging in temperate waters: sensitivity to dimethylsulphide of shearwaters in the Atlantic Ocean and Mediterranean Sea
2014
AbstractMany procellariiforms use olfactory cues to locate food patches over the seemingly featureless ocean surface. In particular, some of them are able to detect and are attracted by dimethylsulfide (DMS), a volatile compound naturally occurring over worldwide oceans in correspondence with productive feeding areas. However, current knowledge is restricted to sub-Antarctic species, and to only one study realized under natural conditions at sea. Here, for the first time, we investigated the response to DMS in parallel in two different environments in temperate waters, the Atlantic Ocean and the Mediterranean Sea, employing Cory's (Calonectris borealis) and Scopoli's shearwaters (Calonectri…
Individual consistency and sex differences in migration strategies of Scopoli’s shearwaters Calonectris diomedea despite year differences
2014
Abstract Recently-developed capabilities for tracking the movements of individual birds over the course of a year or longer has provided increasing evidence for consistent individual differences in migration schedules and destinations. This raises questions about the relative importance of individual consistency versus flexibility in the evolution of migration strategies, and has implications for the ability of populations to respond to climatic change. Using geolocators, we tracked the migrations of Scopoli’s shearwaters Calonectris diomedea breeding in Linosa (Italy) across three years, and analysed timing and spatial aspects of their movements. Birds showed remarkable variation in their …
A new algorithm for the identification of dives reveals the foraging ecology of a shallow-diving seabird using accelerometer data
2017
International audience; The identification of feeding events is crucial to our understanding of the foraging ecology of seabirds. Technology has made small devices, such as time-depth recorders (TDRs) and accelerometers available. However, TDRs might not be sensitive enough to identify shallow dives, whereas accelerometers might reveal more subtle behaviours at a smaller temporal scale. Due to the limitations of TDRs, the foraging ecology of many shallow-diving seabirds has been poorly investigated to date. We thus developed an algorithm to identify dive events in a shallow-diving seabird species, the Scopoli’s shearwater, using only accelerometer data. The accuracy in the identification of…
Conflicts between touristic recreational activities and breeding shearwaters: short-term effect of artificial light and sound on chick weight
2018
Human disturbances are increasingly becoming a conservation concern for many populations of colonial seabirds. Colonially reproducing species are particularly vulnerable to localised disturbances because detrimental elements can simultaneously affect the entire population. Studies of petrels and shearwaters have shown that light pollution, in particular, can be harmful for both fledglings and adults, but little is known of the way such anthropogenic elements affect the quality of parental care at the nest. Chick provisioning in petrels and shearwaters occurs exclusively at night and is also negatively correlated with the amount of moonlight. We tested the hypothesis that high-intensity ligh…