What is that smell? Hummingbirds avoid foraging on resources with defensive insect compounds

Abstract Hummingbirds utilize visual cues to locate flowers, but little is known about the role olfaction plays in nectar foraging despite observations that hummingbirds avoid resources occupied by certain insects. We investigated the behavioral responses of both wild and captive hummingbirds to olfactory cues of hymenopteran floral visitors, including native wood ants (Formica francoeuri), invasive Argentine ants (Linepithema humile), and European honeybees (Apis mellifera). We demonstrate for the first time that hummingbirds use olfaction to make foraging decisions when presented with insect-derived chemical cues under field and aviary conditions. Both wild and captive hummingbirds avoided foraging on feeders with defensive chemicals of F. francoeuri and aggregation pheromones of L. humile, but showed no response to honeybee cuticular hydrocarbons. Our experiments demonstrate the importance of olfaction in shaping hummingbird foraging decisions. Significance statement Recent reviews reveal that avian olfaction is not just limited to vultures and a few taxa. We demonstrate that a very charismatic group, hummingbirds, avoid defensive and aggregatory chemical cues from insects present at nectar resources. Olfactory cues can provide critical information about the presence and potential threat of insect floral visitors. This study raises new questions about the underrated importance of olfaction in avian foraging and specifically, hummingbird foraging.

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Can larval snapper, Pagrus auratus, smell their new home?

Marine and Freshwater Research ◽

10.1071/mf12118 ◽

2012 ◽

Vol 63 (10) ◽

pp. 898 ◽

Cited By ~ 19

Author(s):

C. A. Radford ◽

C. J. Sim-Smith ◽

A. G. Jeffs

Keyword(s):

Chemical Cues ◽

Fish Larvae ◽

Good Evidence ◽

Artificial Seawater ◽

Olfactory Cues ◽

Seagrass Habitat ◽

Pagrus Auratus ◽

Temperate Fish ◽

First Time ◽

Mussel Habitat

The ability to find a suitable settlement habitat after a pelagic larval period represents a significant challenge to marine settlement-stage larvae, and the mechanisms by which they achieve this are poorly understood. There is good evidence that olfactory cues are used by some coral reef fish larvae to locate suitable settlement habitats; however, the same understanding is lacking for marine temperate fish. Here we show for the first time that the larvae of an important commercial and recreational marine temperate fish, Pagrus auratus, can use olfactory cues to orient to appropriate settlement habitat. Using pairwise choice experiments, naive hatchery reared fish were offered water collected from a range of habitats in the Kaipara Harbour, an important nursery area for P. auratus. Larvae selected to swim towards water taken from over seagrass beds, their preferred settlement habitat, than water taken from the harbour entrance, Asian date mussel habitat, artificial seawater or artificial seawater in which seagrass had been soaked. The preference by the fish for water from the seagrass habitat over artificial seawater in which seagrass had been soaked strongly suggests that chemical cues from sources other than seagrass, such as from prey or conspecifics present in the seagrass habitat, may also be involved.

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Newborns’ sensitivity to speed changes as a building block for animacy perception

Scientific Reports ◽

10.1038/s41598-020-79451-3 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Elisa Di Giorgio ◽

Marco Lunghi ◽

Giorgio Vallortigara ◽

Francesca Simion

Keyword(s):

Attentional Bias ◽

Building Block ◽

Visual Cues ◽

Constant Speed ◽

Attentional Biases ◽

Visual Preference ◽

Reverse Sequence ◽

Motion Speed ◽

Speed Change ◽

First Time

AbstractThe human visual system can discriminate between animate beings vs. inanimate objects on the basis of some kinematic cues, such as starting from rest and speed changes by self-propulsion. The ontogenetic origin of such capability is still under debate. Here we investigate for the first time whether newborns manifest an attentional bias toward objects that abruptly change their speed along a trajectory as contrasted with objects that move at a constant speed. To this end, we systematically manipulated the motion speed of two objects. An object that moves with a constant speed was contrasted with an object that suddenly increases (Experiment 1) or with one that suddenly decreases its speed (Experiment 2). When presented with a single speed change, newborns did not show any visual preference. However, newborns preferred an object that abruptly increases and then decreases its speed (Experiment 3), but they did not show any visual preference for the reverse sequence pattern (Experiment 4). Overall, results are discussed in line with the hypothesis of the existence of attentional biases in newborns that trigger their attention towards some visual cues of motion that characterized animate perception in adults.

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Male salamanders remember individuals based on chemical or visual cues

Behaviour ◽

10.1163/156853909x443463 ◽

2009 ◽

Vol 146 (11) ◽

pp. 1485-1498 ◽

Cited By ~ 7

Author(s):

Nancy Kohn ◽

Robert Jaeger

Keyword(s):

Filter Paper ◽

Forest Floor ◽

Visual Cues ◽

Chemical Cues ◽

Plethodon Cinereus ◽

Multiple Cues

AbstractThe use of multiple cues can enhance the detection, recognition, discrimination, and memorability of individuals by receivers. We conducted two experiments, using only males, to test whether territorial red-backed salamanders, Plethodon cinereus, could use only chemical or only visual cues to remember familiar conspecifics. In both experiments, focal males spent significantly more time threatening unfamiliar than familiar male intruders. They also chemoinvestigated the filter paper containing chemical cues of unfamiliar intruders more often than that of familiar intruders. These results suggest that red-backed salamanders can use both chemical and visual cues to recognize familiar individuals, allowing them to distinguish between less threatening neighbours and more threatening intruders in the heterogeneous forest floor habitat, where visual cues alone would not always be available.

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Food Avoidance Learning in Squirrel Monkeys and Common Marmosets

Learning & Memory ◽

10.1101/lm.5.3.193 ◽

1998 ◽

Vol 5 (3) ◽

pp. 193-203

Author(s):

Matthias Laska ◽

Karin Metzker

Keyword(s):

Avoidance Learning ◽

Visual Cues ◽

Squirrel Monkeys ◽

Olfactory Cues ◽

Saimiri Sciureus ◽

Common Marmosets ◽

Food Avoidance ◽

Robust Learning ◽

Olfactory Cue ◽

Potential Food

Using a conditioned food avoidance learning paradigm, six squirrel monkeys (Saimiri sciureus) and six common marmosets (Callithrix jacchus) were tested for their ability to (1) reliably form associations between visual or olfactory cues of a potential food and its palatability and (2) remember such associations over prolonged periods of time. We found (1) that at the group level both species showed one-trial learning with the visual cues color and shape, whereas only the marmosets were able to do so with the olfactory cue, (2) that all individuals from both species learned to reliably avoid the unpalatable food items within 10 trials, (3) a tendency in both species for quicker acquisition of the association with the visual cues compared with the olfactory cue, (4) a tendency for quicker acquisition and higher reliability of the aversion by the marmosets compared with the squirrel monkeys, and (5) that all individuals from both species were able to reliably remember the significance of the visual cues, color and shape, even after 4 months, whereas only the marmosets showed retention of the significance of the olfactory cues for up to 4 weeks. Furthermore, the results suggest that in both species tested, illness is not a necessary prerequisite for food avoidance learning but that the presumably innate rejection responses toward highly concentrated but nontoxic bitter and sour tastants are sufficient to induce robust learning and retention.

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Smelling home: a good solution for burrow-finding in nocturnal petrels?

Journal of Experimental Biology ◽

10.1242/jeb.205.16.2519 ◽

2002 ◽

Vol 205 (16) ◽

pp. 2519-2523 ◽

Cited By ~ 7

Author(s):

Francesco Bonadonna ◽

Vincent Bretagnolle

Keyword(s):

Olfactory System ◽

Visual Cues ◽

Zinc Sulphate ◽

Olfactory Cues ◽

Nocturnal Activity ◽

Complete Darkness ◽

Visual Guidance ◽

Nest Recognition ◽

Return Home ◽

Nesting Habits

SUMMARY Many burrowing petrels are able to return to their nests in complete darkness. The well-developed anatomy of their olfactory system and the attraction that food-related odour cues have for some petrel species suggest that olfaction may be used to recognize the burrow. In contrast,surface-nesting petrels may rely on visual cues to recognise their nest. We performed experiments on nine species of petrel (with different nesting habits) rendered anosmic either by plugging the nostrils or by injecting zinc sulphate onto the nasal epithelium. Compared with shamtreated control birds,we found that anosmia impaired nest recognition only in species that nest in burrows and that return home in darkness. Therefore, petrels showing nocturnal activity on land may rely on their sense of smell to find their burrows, while petrels showing diurnal activity or surface nesters may disregard olfactory cues in favour of visual guidance.

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Olfactory Cues Modify and Enhance Responses to Visual Cues in the Common Marmoset (Callithrix jacchus)

Journal of Primatology ◽

10.4172/2167-6801.1000102 ◽

2012 ◽

Vol 01 (01) ◽

Cited By ~ 1

Author(s):

Caralyn Kemp Gisela Kaplan

Keyword(s):

Visual Cues ◽

Common Marmoset ◽

Callithrix Jacchus ◽

Olfactory Cues ◽

The Common

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Detection of Chlamydia psittaci and Chlamydia ibidis in the Endangered Crested Ibis (Nipponia nippon)

Epidemiology and Infection ◽

10.1017/s0950268819002231 ◽

2020 ◽

Vol 148 ◽

Cited By ~ 2

Author(s):

Zhaocai Li ◽

Ping Liu ◽

Jia Hou ◽

Guanglan Xu ◽

Junfeng Zhang ◽

...

Keyword(s):

Avian Species ◽

Chlamydia Psittaci ◽

Potential Threat ◽

High Genetic Diversity ◽

Obligate Intracellular ◽

Nipponia Nippon ◽

Crested Ibis ◽

Faecal Samples ◽

First Time ◽

Avian Chlamydiosis

Abstract Chlamydia spp. are a group of obligate intracellular pathogens causing a number of diseases in animals and humans. Avian chlamydiosis (AC), caused by Chlamydia psittaci (C. psittaci) as well as new emerging C. avium, C. gallinacea and C. ibidis, have been described in nearly 500 avian species worldwidely. The Crested Ibis (Nipponia nippon) is a world endangered avian species with limited population and vulnerable for various infections. To get a better understanding of the prevalence of Chlamydia spp. in the endangered Crested Ibis, faecal samples were collected and analysed. The results confirmed that 20.20% (20/99) of the faecal samples were positive for Chlamydiaceae and were identified as C. ibidis with co-existence of C. psittaci in one of the 20 positive samples. In addition, ompA sequence of C. psittaci obtained in this study was classified into the provisional genotype Matt116, while that of C. ibidis showed high genetic diversity, sharing only 77% identity with C. ibidis reference strain 10-1398/6. We report for the first time the presence of C. ibidis and C. psittaci in the Crested Ibis, which may indicate a potential threat to the endangered birds and should be aware of the future protection practice.

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