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To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.anbehav.2009.05.002 Byline: Roman D. Furrer, Marta B. Manser Abstract: Many species use specific vocalizations that attract conspecifics to food sources or that recruit other group members to inspect secondary predator cues or to mob predators. However, little is known regarding the variation in the acoustic structure of such calls and the associated meaning. In the cooperatively breeding banded mongoose, Mungos mungo, we investigated calls produced in the context of group recruitment to three different stimulus types: (1) secondary predator cues; (2) snakes; and (3) members of rival groups. Calls produced in response to predator faeces differed from the harsher variants elicited by snakes and rival groups, but the latter two elicited similar calls. Only a few calls of intermediate acoustic structure were produced in response to the different stimulus categories. Playbacks of calls elicited by the different stimuli caused individuals to approach the speaker in the same way. However, calls elicited specifically by snakes and rival mongooses resulted in a higher proportion of receivers responding and a faster receiver response than calls elicited by faeces. This suggests a graded rather than a discrete recruitment call system. Thus, despite obvious differences in stimulus type and the purpose of recruitment, the acoustic structure of calls conveys information about the risk of the encountered stimulus and not the stimulus type itself, allowing receivers to adjust their response according to the urgency. Since calling continued for prolonged periods after all group members had gathered around the callers, these calls may also function to deter rivals and to coordinate the subsequent group response. Author Affiliation: Zoologisches Institut, Universitat Zurich, Switzerland Article History: Received 17 October 2008; Revised 11 November 2008; Accepted 1 May 2009 Article Note: (miscellaneous) MS. number: 08-00666R

ABSTRACT Assessing the role of local populations in a landscape context has become increasingly important in the fields of conservation biology and ecology. A growing number of studies attempt to determine the source-sink status of local populations. As the source-sink concept is commonly used for management decisions in nature conservation, accurate assessment approaches are crucial. Based on a systematic literature review of studies published between 2002 and 2013, we evaluated a priori predictions on methodological and biological factors that may influence the occurrence of source or sink populations. The review yielded 90 assessments from 73 publications that included qualitative and quantitative evidence for either source or sink population(s) for one or multiple species. Overall, sink populations tended to occur more often than source populations. Moreover, the occurrence of source or sink populations differed among taxonomic classes. Sinks were more often found than sources in mammals, while there was a non-significant trend for the opposite to be true for amphibians. Univariate and multivariate analyses showed that the occurrence of sources was positively related to connectivity of local populations. Our review furthermore highlights that more than 25 years after Pulliam's widely cited publication on 'sources, sinks, and population regulation', in-depth assessments of the source-sink status of populations based on combined consideration of demographic parameters such as fecundity, survival, emigration and immigration are still scarce. To increase our understanding of source-sink systems from ecological, evolutionary and conservation-related perspectives, we recommend that forthcoming studies on source-sink dynamics should pay more attention to the study design (i.e. connectivity of study populations) and that the assessment of the source-sink status of local populations is based on λ values calculated from demographic rates. [ABSTRACT FROM AUTHOR]