0000000000374727
AUTHOR
Giacomo Dell'omo
First GPS-tracking of Cory’s shearwater in the Mediterranean Sea.
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…
Seabirds mated for life migrate separately to the same places: behavioural coordination or shared proximate causes?
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 shearwaters (Calonectris diomedea) from the Southern Mediterranean
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…
Individual consistency and sex differences in migration strategies of Scopoli’s shearwaters Calonectris diomedea despite year differences
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 …
Year-round variation in the isotopic niche of Scopoli's shearwater (Calonectris diomedea) breeding in contrasting sea regions of the Mediterranean Sea
Top marine predators are key components of marine food webs. Among them, long-distance migratory seabirds, which travel across different marine ecosystems over the year, may experience important year-round changes in terms of oceanographic conditions and availability of trophic resources. We tested whether this was the case in the Scopoli’s shearwater (Calonectris diomedea), a trans-equatorial migrant and top predator, by sampling birds breeding in three environmentally different regions of the Mediterranean Sea. The analysis of positional data and stable isotopes (δ13 C and δ15N) of target feathers revealed that birds from the three regions were spatially segregated during the breeding per…
Unconditional adoption rules out the need for parent–offspring recognition in a single‐brooded colonial seabird
Parent–offspring recognition (POR) is fundamental in colonial birds when the potential intermingling of chicks is higher due to the large number and proximity of nests. In species with isolated nests, where chick presence in the nest is strong contextual evidence of kinship, there might be circumstances when the parent might doubt the identity of the chick, but not enough to reject it. Olfactory-based recognition of conspecifics and nest sites in birds has gained strong evidence suggesting a potential role of olfaction in POR. Despite that, there are no studies testing it. We used Scopoli's shearwater (Calonectris diomedea) as model colonial single-brooded species with a developed olfactory…
Conflicts between touristic recreational activities and breeding shearwaters: short-term effect of artificial light and sound on chick weight
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…