FRINK Linked Data Fragments server

Matches in SemOpenAlex for { <https://semopenalex.org/work/W3025764026> ?p ?o ?g. }

• W3025764026 abstract "Humpback whales (Megaptera novaeangliae) are one of the most vocally diverse of the baleen whale species. Most research on humpback whale communication has focused on the repetitive and highly stereotyped songs produced exclusively by males. Comparatively few studies have been carried out on their non-song vocalisations, which are produced by males, females, and calves. Post-calving females face unique challenges during these whales’ seasonal migrations, as they must remain in contact with their young calves while travelling long distances. Calves are a substantial investment for female humpback whales, so their ability to mediate proximity during migration is likely a significant contributor to calf fitness and survival, as well as female reproductive success. Presumably, vocal exchanges between the two play an important role in maintaining closeness, as acoustic communication is more efficient and reliable than visual cues for such a highly mobile species in the light-limited, low visibility marine environment.This thesis aimed to investigate the vocal behaviour of female-calf pairs while travelling southwards from tropical calving grounds to polar feeding areas along the east Australian migratory corridor. This was achieved by 1) quantifying the vocal repertoire of these pairs and establishing the information (e.g., static signaller features such as age and body size) that may be contained within their calls, 2) providing robust baseline information on the size of the female-calf humpback whale communication space in natural noise conditions, 3) examining how their vocal activity (i.e., call type, rate, received level and active space) is affected by their behavioural state (i.e., resting or travelling) in order to determine the periods during which acoustic contact is most crucial, and 4) determining whether these pairs modify their calling and/or migratory movement behaviour in response to their social environment (i.e., the presence of singing males or other neighbouring groups) to gain an understanding of their communication strategies.The female-calf vocal repertoire was found to contain nine common sound types, the parameters of which likely encode socially relevant information regarding signaller age and body size. Sound types were quantitatively separated into two clusters. One cluster contained calls that were considerably longer in duration, lower in frequency, and narrower in bandwidth than those in the second cluster. As acoustic features can vary within a basic range that is imposed by the constraints of physical development and body size, young animals tend to produce less structured calls that are shorter in duration and higher in frequency than those of adults. This suggests that the calls in clusters one and two were likely to have been produced by the adult females and calves, respectively. These calls were then analysed as a function of female-calf behavioural state. Both adult females and calves called significantly more often when ‘resting/milling’ than when ‘travelling’. This is likely because adult females had significantly longer dive durations during these periods, indicating a higher chance of female-calf separation when resting and, therefore, a greater need to maintain acoustic contact. Call repertoire also varied between behavioural states, with the different call structures likely a response to activity and proximity to the receiver. Notably, calls with longer durations and lower frequencies tended to be produced most often when travelling, possibly due to enhanced detectability. Finally, we found that less than 15% of female-calf calls were estimated to propagate beyond 2 km, indicating a restricted communication space regardless of state.However, the signals produced by these pairs may unintentionally elicit unwanted interactions with neighbouring conspecifics that can prove energetically costly and physically dangerous to young calves. To prevent acoustic detection, it is presumed that female-calf pairs employ strategies to avoid potential male harassment and/or competitive aggression. Therefore, they must choose the strategy (i.e., vocal crypsis and/or behavioural avoidance) that best accounts for the prevailing social environment. Our results suggest that bystanders cause only minor modifications to the vocal behaviour of solitary female-calf pairs. We propose that instead of dynamically altering their acoustics, these pairs have developed calls that are naturally difficult to detect (i.e., produced at low rates with reduced acoustic level and a restricted active space, as compared to other humpback whale groups), and compensate for nearby groups by significantly modifying their movement behaviour (i.e., maintaining spatial separation, moving inshore to shallower water). Such behavioural avoidance strategies, in addition to preventing direct interaction, may allow females to more easily maintain acoustic contact with their calves by allowing these pairs to continue calling at ‘normal’ rates and levels.This thesis is the first to focus exclusively on the fine-scale communication behaviour of humpback whale female-calf pairs and does so during the migratory period when females with dependent young are at increased risk of separation. This project represents an important step in expanding our understanding of how these pairs use acoustics under natural ambient noise conditions, which is a necessary foundation from which to explore the potential impacts of anthropogenic disturbance and vocalisation masking on these pairs (e.g., decreased calf survival) in the future." @default.
• W3025764026 created "2020-05-21" @default.
• W3025764026 creator A5089594556 @default.
• W3025764026 date "2020-04-21" @default.
• W3025764026 modified "2023-09-28" @default.
• W3025764026 title "Acoustic communication of female-calf humpback whales during migration" @default.
• W3025764026 cites W1977281722 @default.
• W3025764026 cites W1977578661 @default.
• W3025764026 cites W1980752137 @default.
• W3025764026 cites W2001431449 @default.
• W3025764026 cites W2085993108 @default.
• W3025764026 cites W2104576056 @default.
• W3025764026 cites W2111264665 @default.
• W3025764026 cites W2147302581 @default.
• W3025764026 doi "https://doi.org/10.14264/uql.2020.558" @default.
• W3025764026 hasPublicationYear "2020" @default.
• W3025764026 type Work @default.
• W3025764026 sameAs 3025764026 @default.
• W3025764026 citedByCount "1" @default.
• W3025764026 countsByYear W30257640262020 @default.
• W3025764026 crossrefType "dissertation" @default.
• W3025764026 hasAuthorship W3025764026A5089594556 @default.
• W3025764026 hasBestOaLocation W30257640262 @default.
• W3025764026 hasConcept C136764020 @default.
• W3025764026 hasConcept C18903297 @default.
• W3025764026 hasConcept C205649164 @default.
• W3025764026 hasConcept C22041718 @default.
• W3025764026 hasConcept C22641795 @default.
• W3025764026 hasConcept C2776659692 @default.
• W3025764026 hasConcept C2777324915 @default.
• W3025764026 hasConcept C2777704720 @default.
• W3025764026 hasConcept C2779234561 @default.
• W3025764026 hasConcept C41008148 @default.
• W3025764026 hasConcept C54355233 @default.
• W3025764026 hasConcept C59726852 @default.
• W3025764026 hasConcept C86803240 @default.
• W3025764026 hasConcept C92878468 @default.
• W3025764026 hasConceptScore W3025764026C136764020 @default.
• W3025764026 hasConceptScore W3025764026C18903297 @default.
• W3025764026 hasConceptScore W3025764026C205649164 @default.
• W3025764026 hasConceptScore W3025764026C22041718 @default.
• W3025764026 hasConceptScore W3025764026C22641795 @default.
• W3025764026 hasConceptScore W3025764026C2776659692 @default.
• W3025764026 hasConceptScore W3025764026C2777324915 @default.
• W3025764026 hasConceptScore W3025764026C2777704720 @default.
• W3025764026 hasConceptScore W3025764026C2779234561 @default.
• W3025764026 hasConceptScore W3025764026C41008148 @default.
• W3025764026 hasConceptScore W3025764026C54355233 @default.
• W3025764026 hasConceptScore W3025764026C59726852 @default.
• W3025764026 hasConceptScore W3025764026C86803240 @default.
• W3025764026 hasConceptScore W3025764026C92878468 @default.
• W3025764026 hasLocation W30257640261 @default.
• W3025764026 hasLocation W30257640262 @default.
• W3025764026 hasOpenAccess W3025764026 @default.
• W3025764026 hasPrimaryLocation W30257640261 @default.
• W3025764026 hasRelatedWork W1982953162 @default.
• W3025764026 hasRelatedWork W1986837431 @default.
• W3025764026 hasRelatedWork W1990783553 @default.
• W3025764026 hasRelatedWork W2078080527 @default.
• W3025764026 hasRelatedWork W2084484971 @default.
• W3025764026 hasRelatedWork W2121432393 @default.
• W3025764026 hasRelatedWork W2185574821 @default.
• W3025764026 hasRelatedWork W2288567327 @default.
• W3025764026 hasRelatedWork W2613745563 @default.
• W3025764026 hasRelatedWork W2793263361 @default.
• W3025764026 hasRelatedWork W2793285384 @default.
• W3025764026 hasRelatedWork W2898258711 @default.
• W3025764026 hasRelatedWork W3126716007 @default.
• W3025764026 hasRelatedWork W3133315072 @default.
• W3025764026 hasRelatedWork W3166756130 @default.
• W3025764026 hasRelatedWork W3193492481 @default.
• W3025764026 hasRelatedWork W3198237380 @default.
• W3025764026 hasRelatedWork W3206950743 @default.
• W3025764026 hasRelatedWork W3213907297 @default.
• W3025764026 hasRelatedWork W588539918 @default.
• W3025764026 isParatext "false" @default.
• W3025764026 isRetracted "false" @default.
• W3025764026 magId "3025764026" @default.
• W3025764026 workType "dissertation" @default.