02273nas a2200205 4500008004100000245010700041210006900148520160100217653001601818653001801834653002001852653001401872653002901886653001601915653001701931653002901948100002301977700002302000856004402023 2020 eng d00aDoes the presence of an observer affect a bird's occurrence rate or singing rate during a point count?0 aDoes the presence of an observer affect a birds occurrence rate 3 a

The approach or presence of an observer may affect the behavior of nearby birds, rendering them either more or less detectable than when no observer is present due to a change in singing rates. To test whether there are systematic detection biases associated with the presence of an observer during point count bird surveys, we compared the occurrence and singing rates of birds during a 10‐min period immediately preceding the time when an observer arrived to conduct a count and during the formal count itself by extracting song information from autonomous sound recorders. We obtained recordings of 36 species of birds detected at ≥5 locations in one of three vegetation types, including burned conifer forest, green conifer/riparian streamside forest, and riparian bottomland/marshland. We found that species richness and both the probability of occurrence and singing rate for any of the species recorded were unaffected by the presence of an observer. In addition, the probability of occurrence did not differ significantly among four 2.5‐min recording sessions during 10‐min counts when an observer was present. Thus, the presence of an observer did not appear to introduce any detectable systematic bias that would make bird lists or unadjusted occurrence rates inaccurate on that basis alone. In addition, rates of bird occurrence across 2.5‐min temporal subsets of a 10‐min count did not vary in a systematic way that would violate the assumption of equal occupancy across adjacent time periods as sometimes used to build detection histories in occupancy modeling.

10abird survey10adetectability10aobserver effect10aoccupancy10apassive acousticsampling10apoint count10asinging rate10autonomous recording unit1 aHutto, Richard, L.1 aHutto, Russell, R. uhttp://doi.wiley.com/10.1111/jofo.1232902388nas a2200241 4500008004100000245010700041210006900148260001600217300001400233490000800247520168200255653001401937653001101951653001801962653001201980653001301992653001102005100002102016700001802037700002002055700001702075856005402092 2018 eng d00aRavens adjust their antipredatory responses to con- and hetero-specific alarms to the perceived threat0 aRavens adjust their antipredatory responses to con and heterospe cJan-08-2018 a609 - 6160 v1243 a

Heterospecific alarm calls are typically found in situations where multiple species have a common predator. In birds, they are particularly common in mixed mixed‐species flocks. In species with highly developed social and cognitive abilities like corvids, there is the potential for differential responses to heterospecific vs. conspecific calls according to the riskiness of the habitat. We tested the responses of free‐ranging ravens (Corvus corax) to conspecific alarm calls and compared them to heterospecific alarm calls of jackdaws (Corvus monedula). We observed the proportion of ravens leaving the feeding site after the con‐ or hetero‐specific playback was presented in a situation of low threat (wild boar—Sus scrofa enclosure) and high threat of predation (wolf—Canis lupus enclosure). We show that ravens responded to conspecific calls more intensively at the wolves than at the wild boar, but the response to conspecific calls was in both enclosures stronger than to the control (great tit—Parus major song). The response to the heterospecific alarm was also stronger in the wolves’ enclosure, but it did not differ from control in the wild boar enclosure. These findings suggest that ravens are aware of the meaning of the jackdaw alarm calls, but they respond to it only in a situation of high predatory threat (wolves are present). In the wild boar enclosure, the ravens probably consider jackdaws warning against some other predator, very probably harmless to ravens. This interpretation requires further testing, as both enclosures differ also in respect to other parameters like food quality and shelter availability.

10aavoidance10acorvid10ahonest signal10ajackdaw10apredator10athreat1 aNácarová, Jana1 aVeselý, Petr1 aBugnyar, Thomas1 aTregenza, T. uhttp://doi.wiley.com/10.1111/eth.2018.124.issue-802171nas a2200265 4500008004100000022001400041245008800055210006900143260001600212300001600228490000700244520143100251653001401682653001001696653001201706653002001718653001901738653001601757653002401773653001101797653001201808100001701820700001901837856004901856 2017 eng d a2329-929000aOn-Bird Sound Recordings: Automatic Acoustic Recognition of Activities and Contexts0 aOnBird Sound Recordings Automatic Acoustic Recognition of Activi cJan-06-2017 a1193 - 12060 v253 a

We introduce a novel approach to studying animal behavior and the context in which it occurs, through the use of microphone backpacks carried on the backs of individual free-flying birds. These sensors are increasingly used by animal behavior researchers to study individual vocalizations of freely behaving animals, even in the field. However, such devices may record more than an animal's vocal behavior, and have the potential to be used for investigating specific activities (movement) and context (background) within which vocalizations occur. To facilitate this approach, we investigate the automatic annotation of such recordings through two different sound scene analysis paradigms: A scene-classification method using feature learning, and an event-detection method using probabilistic latent component analysis. We analyze recordings made with Eurasian jackdaws (Corvus monedula) in both captive and field settings. Results are comparable with the state of the art in sound scene analysis; we find that the current recognition quality level enables scalable automatic annotation of audio logger data, given partial annotation, but also find that individual differences between animals and/or their backpacks limit the generalization from one individual to another. we consider the interrelation of “scenes” and “events” in this particular task, and issues of temporal resolution.

10aacoustics10abirds10acontext10aevent detection10aimage analysis10amicrophones10apattern recognition10aspeech10azoology1 aStowell, Dan1 aGill, Lisa, F. uhttp://ieeexplore.ieee.org/document/7933044/