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Wandering albatrosses routinely forage over thousands of kilometres of open ocean, but the sensory mechanisms used in the food search itself have not been completely elucidated. Recent telemetry studies show that some spatial behaviours of the species are consistent with the 'multimodal foraging strategy' hypothesis which proposes that birds use a combination of olfactory and visual cues while foraging at sea. The 'multimodal foraging strategy' hypothesis, however, still suffers from a lack of experimental evidence, particularly regarding the olfactory capabilities of wandering albatrosses. As an initial step to test the hypothesis, we carried out behavioural experiments exploring the sensory capabilities of adult wandering albatrosses at a breeding colony. Three two-choice tests were designed to investigate the birds' response to olfactory and visual stimuli, individually or in combination. Perception of the different stimuli was assessed by comparing the amount of exploration directed towards an 'experimental' display or a 'control' display. Our results indicate that birds were able to perceive the three types of stimulus presented: olfactory, visual and combined. Moreover, olfactory and visual cues were found to have additional effects on the exploratory behaviours of males. This simple experimental demonstration of reasonable olfactory capabilities in the wandering albatross supports the 'multimodal foraging strategy' and is consistent with recent hypotheses of the evolutionary history of procellariiforms. [ABSTRACT FROM AUTHOR]

Procellariiform seabirds (the petrels, albatrosses and shearwaters) are recognized for their acute sense of smell. These pelagic seabirds forage over thousands of miles of ocean to find patchily distributed prey resources. Over the past decade, much headway has been made in unravelling the variety of olfactory foraging strategies that Antarctic species employ, and it is becoming clearer that olfaction plays a key role in foraging, particularly for burrow nesting species. Now we are beginning to explore how these behaviours develop in chicks. Procellariiform chicks fledge and survive the open seas without aid or instruction from a parent, but how they are able to accomplish this task is unknown. Here we explore whether chicks leave the nest pre-tuned to olfactory cues necessary for foraging. In this study, we tested the hypothesis that blue petrel chicks (Halobaena caerulea) are able to detect and orient to a foraging cue (dimethyl sulphide, DMS) used by adults without ever having experienced this odour at sea. We first established that chicks could detect DMS at a biologically relevant concentration that they will later naturally encounter at sea (<10pmol l-1). We then performed preference tests in a Y-maze on a group of birds 1–6 days before they fledged. Sixteen out of 20 fledglings preferred DMS (e.g. DMS+propylene glycol) to a ‘control’ odour (propylene glycol alone). Our results suggest that chicks can detect and may already recognize DMS as an orientation cue even before they leave the nest to forage for the first time. [ABSTRACT FROM AUTHOR]

Abstract: Because passerine birds have a very small relative olfactory bulb size, they have been considered to have weak olfactory capacities for decades. Recent investigations however suggest that breeding female blue tits (Parus caeruleus) are sensitive to lavender odour in the reproductive context of building and maintaining the nest. Here, we present results of an olfactory conditioning experiment in blue tits held in semi-natural conditions during the breeding season. We show that captive male blue tits, trained to associate lavender odour with a food reward, are more attracted to an empty feeder box emitting lavender odour than an odourless empty feeder box. Females did not distinguish significantly between empty feeders with and without lavender odour during the test phase, although they responded positively at the end of the training phase. These results suggest that male blue tits can use olfaction in a context not related to nest building. Additional experiments will be required to better understand the observed sex differences in response to the experimental set up, and in what context free-ranging individuals use olfaction. [Copyright &y& Elsevier]