Familiarity with the experimenter influences the performance of Common ravens (Corvus corax) and Carrion crows (Corvus corone corone) in cognitive tasks

Research on nest occupation and prey grabbing by saker falcon (Falco cherrug) on power lines in Vojvodina (Serbia) was done in the period from 1986 to 2004. During three specially analyzed periods, saker falcon took the nests of raven (Corvus corax) in 91% of a total of 22 cases of nest occupation, and those of hooded crow (Corvus corone cornix) in only 9%. Saker falcon regularly grabs prey from different birds that occasionally or constantly spend time around power lines [Kestrel (Falco tinnunculus), hobby (Falco subbuteo), hooded crow (Corvus corone cornix), jack-daw (Corvus monedula), marsh harrier (Circus aeruginosus), hen harrier (Circus cyaneus), buzzard (Buteo buteo), and raven (Corvus corax)]. One year a studied pair of saker falcons on a power line in Donji Srem, Serbia grabbed prey from five different species of birds. Out of a total of 40 cases of prey grabbing in the period from January to December, as much 70% of the grabbed prey was taken from kestrel (Falco tinnunculus). During the winter and early spring, prey was grabbed predominantly by males; after May, prey was sometimes grabbed by females as well. Most of the grabbed prey was common vole (Microtus arvalis).

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Explorative innovators and flexible use of social information in common ravens (Corvus corax) and carrion crows (Corvus corone).

Journal of Comparative Psychology ◽

10.1037/com0000039 ◽

2016 ◽

Vol 130 (4) ◽

pp. 328-340 ◽

Cited By ~ 4

Author(s):

Rachael Miller ◽

Christine Schwab ◽

Thomas Bugnyar

Keyword(s):

Social Information ◽

Corvus Corax ◽

Corvus Corone

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Behavioral Responses of Captive Corvids to the Presence of Visitors

Animal Behavior and Cognition ◽

10.26451/abc.08.04.03.2021 ◽

2021 ◽

Vol 8 (4) ◽

pp. 481-492

Author(s):

Claudia A.F. Wascher ◽

Niklas Baur ◽

Marietta Hengl ◽

Carina Köck ◽

Teresa Pegger ◽

...

Keyword(s):

Behavioral Responses ◽

Behavioral Changes ◽

Corvus Corax ◽

Welfare Impacts ◽

Close Proximity ◽

Corvus Corone ◽

Control Situations ◽

Affiliative Behaviors

Behavioral responses of captive animals to the presence of visitors in zoos and wildlife parks can be interpreted as signs of negative (disturbance), neutral or positive (enrichment) welfare. In the present study, we investigated behavioral responses of captive common ravens, Corvus corax and crows, Corvus corone, to the presence of visitors in general and to the proximity or distance of visitors to the aviary respectively. Duration of affiliative behaviors, feeding and stress-related behaviors did not change when visitors were present compared to control situations without visitors being present. Both corvid species showed less head up behavior when visitors were in sight compared to the control condition. In contrast, preening of crows significantly increased when visitors were within two meters of the aviary compared to the control condition. The same relationship was found in regard to increase in vocalization for common ravens, but not for crows. Our results indicate that corvids, housed in a wildlife park for several years, still show behavioral responses to the presence of human visitors in close proximity to their enclosure. Overall, we did not find clear indications for reduced welfare due to visitor presence, such as increased locomotion or stress-related behaviors. We therefore conclude that the described behavioral changes are not indicative of any negative welfare impacts of visitor presence.

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The Effect of Retest Practice on the Speed-Ability Relationship

European Psychologist ◽

10.1027/1016-9040.9.1.24 ◽

2004 ◽

Vol 9 (1) ◽

pp. 24-31 ◽

Cited By ~ 6

Author(s):

Sybille Rockstroh ◽

Karl Schweizer

Keyword(s):

Reaction Time ◽

Skill Acquisition ◽

Reaction Times ◽

Cognitive Tasks ◽

General Intelligence ◽

Attention Switching ◽

Letter Comparison ◽

Sternberg Paradigm ◽

The Relationship ◽

Elementary Cognitive Tasks

Effects of four retest-practice sessions separated by 2 h intervals on the relationship between general intelligence and four reaction time tasks (two memory tests: Sternberg's memory scanning, Posner's letter comparison; and two attention tests: continuous attention, attention switching) were examined in a sample of 83 male participants. Reaction times on all tasks were shortened significantly. The effects were most pronounced with respect to the Posner paradigm and smallest with respect to the Sternberg paradigm. The relationship to general intelligence changed after practice for two reaction time tasks. It increased to significance for continuous attention and decreased for the Posner paradigm. These results indicate that the relationship between psychometric intelligence and elementary cognitive tasks depends on the ability of skill acquisition. In the search for the cognitive roots of intelligence the concept of learning seems to be of importance.

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Effects of Fatigue on Cognitive Performance in Long-Duration Simulated Flight Missions

Aviation Psychology and Applied Human Factors ◽

10.1027/2192-0923/a000191 ◽

2020 ◽

Vol 10 (2) ◽

pp. 82-93

Author(s):

Eduardo Rosa ◽

Ola Eiken ◽

Mikael Grönkvist ◽

Roger Kölegård ◽

Nicklas Dahlström ◽

...

Keyword(s):

Executive Functions ◽

Task Performance ◽

Cognitive Performance ◽

Cognitive Tasks ◽

Fatigue Index ◽

Fighter Aircraft ◽

Long Duration ◽

Metacognitive Accuracy

Abstract. Fighter pilots may be exposed to extended flight missions. Consequently, there is increasing concern about fatigue. We investigated the effects of fatigue and cognitive performance in a simulated 11-hr mission in the 39 Gripen fighter aircraft. Five cognitive tasks were used to assess cognitive performance. Fatigue was measured with the Samn–Perelli Fatigue Index. Results showed that performance in the non-executive task degraded after approximately 7 hr. Fatigue ratings showed a matching trend to the performance in this task. Performance in tasks taxing executive functions did not decline. We interpreted that fatigue can be overridden by increased attentional effort for executive tasks but not for non-executive components of cognition. Participants underestimated their performance and metacognitive accuracy was not influenced by fatigue.

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