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Jay Barlow - One of the best experts on this subject based on the ideXlab platform.
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Diel Variation in beaked whale diving behavior
Marine Mammal Science, 2008Co-Authors: Robin W. Baird, Daniel L. Webster, Gregory S. Schorr, Daniel J. Mcsweeney, Jay BarlowAbstract:We investigate Diel Variation in beaked whale diving behavior using data from time–depth recorders deployed on six Blainville’s (Mesoplodon densirostris) (255 h) and two Cuvier’s (Ziphius cavirostris) (34 h) beaked whales. Deep foraging dives (>800 m) occurred at similar rates during the day and night for Blainville’s beaked whales, and there were no significant Diel differences in ascent rates, descent rates, or mean or maximum depths or durations for deep dives. Dive to mid-water depths (100–600 m) occurred significantly more often during the day (mean = 1.59 h −1 ) than at night (mean = 0.26 h −1 ). Series of progressively shallower “bounce” dives were only documented to follow the deep, long dives made during the day; at night whales spent more time in shallow (<100 m) depths. Significantly slower ascent rates than descent rates were found following deep foraging dives both during the day and night. Similar patterns were found for the Cuvier’s beaked whales. Our results suggest that so-called “bounce” dives do not serve a physiological function, although the slow ascents may. This Diel Variation in behavior suggests that beaked whales may spend less time in surface waters during the day to avoid
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Diel Variation in beaked whale diving behavior
Marine Mammal Science, 2008Co-Authors: Robin W. Baird, Daniel L. Webster, Gregory S. Schorr, Daniel J. Mcsweeney, Jay BarlowAbstract:We investigate Diel Variation in beaked whale diving behavior using data from time–depth recorders deployed on six Blainville’s (Mesoplodon densirostris) (255 h) and two Cuvier’s (Ziphius cavirostris) (34 h) beaked whales. Deep foraging dives (>800 m) occurred at similar rates during the day and night for Blainville’s beaked whales, and there were no significant Diel differences in ascent rates, descent rates, or mean or maximum depths or durations for deep dives. Dive to mid-water depths (100–600 m) occurred significantly more often during the day (mean = 1.59 h −1 ) than at night (mean = 0.26 h −1 ). Series of progressively shallower “bounce” dives were only documented to follow the deep, long dives made during the day; at night whales spent more time in shallow (
Kenneth W Able - One of the best experts on this subject based on the ideXlab platform.
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Diel Variation in the pelagic fish assemblage in a temperate estuary
Estuaries and Coasts, 2008Co-Authors: Stacy M. Hagan, Kenneth W AbleAbstract:The pelagic fish assemblage within a temperate estuary was examined to determine if there were Diel differences in species richness, total abundance, biomass, and species composition. These comparisons were made over both seasonal (January–December 1996) and annual (August–November 1995; August–December 1996) scales with pop net collections in a shallow (<2 m MLW) embayment within Great Bay in southern New Jersey, USA. In the complete year of sampling in 1996, more than 335,000 pelagic fish, representing 13 families (23 species), were collected during Diel sampling with 12 species constituting over 99.9% of the total catch including Clupea harengus (84%), Menidia menidia (10%), and Anchoa mitchilli (4%). A detailed examination determined that nighttime species richness, total abundance and biomass may have been enhanced during some seasons by using artificial light. Diel Variation in species composition was similar regardless of the use of the artificial light in all seasons but fall. Annual comparisons between 1995 and 1996 during late summer and fall found these results to be consistent. In general, these findings point out the importance of sampling during both day and night to understand the movement and abundance patterns of estuarine pelagic fishes and their ecological significance in temperate estuaries.
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Diel Variation in the Pelagic Fish Assemblage in a Temperate Estuary
Estuaries and Coasts, 2007Co-Authors: Stacy M. Hagan, Kenneth W AbleAbstract:The pelagic fish assemblage within a temperate estuary was examined to determine if there were Diel differences in species richness, total abundance, biomass, and species composition. These comparisons were made over both seasonal (January–December 1996) and annual (August–November 1995; August–December 1996) scales with pop net collections in a shallow (
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Diel Variation in decapod crustacean and fish assemblages in new jersey polyhaline marsh creeks
Estuarine Coastal and Shelf Science, 1993Co-Authors: Rodney A Rountree, Kenneth W AbleAbstract:Diel Variation in fish and decapod crustacean abundance and species assemblages were examined in two studies to determine patterns of subtidal and intertidal marsh creek habitat use in a southern New Jersey estuary. In the first study, two subtidal marsh creeks were sampled with weirs from April-November 1988 (n = 42) and seines from July-November 1988 (n = 33), while in the second study two intertidal creeks were sampled with weirs from July-October 1989 (n = 28). Fish and decapod species assemblages captured in subtidal weir, subtidal seine and intertidal weir, as measured by both relative abundance and canonical discrimination analyses, were all highly affected by Diel period. Total abundance and abundances of 15 species of fish and decapods exhibited significant Diel differences, some of which were strongly influenced by season and life history stage (i.e. size cohorts). A detailed examination of the most abundant species, Menidia menidia, reveals that adults were more abundant during the day in early summer, suggesting diurnal reproductive movements into the creeks. In contrast, young-of-the-year cohorts were significantly more abundant at night during the late summer and fall, suggesting nocturnal movement into shallow marsh creek habitats. Our observations of strong Diel differences in species assemblages point out the need for both day and night sampling in marsh habitats, if the importance of these habitats to fishes and decapods are to be fully understood.
Robin W. Baird - One of the best experts on this subject based on the ideXlab platform.
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Diel Variation in beaked whale diving behavior
Marine Mammal Science, 2008Co-Authors: Robin W. Baird, Daniel L. Webster, Gregory S. Schorr, Daniel J. Mcsweeney, Jay BarlowAbstract:We investigate Diel Variation in beaked whale diving behavior using data from time–depth recorders deployed on six Blainville’s (Mesoplodon densirostris) (255 h) and two Cuvier’s (Ziphius cavirostris) (34 h) beaked whales. Deep foraging dives (>800 m) occurred at similar rates during the day and night for Blainville’s beaked whales, and there were no significant Diel differences in ascent rates, descent rates, or mean or maximum depths or durations for deep dives. Dive to mid-water depths (100–600 m) occurred significantly more often during the day (mean = 1.59 h −1 ) than at night (mean = 0.26 h −1 ). Series of progressively shallower “bounce” dives were only documented to follow the deep, long dives made during the day; at night whales spent more time in shallow (<100 m) depths. Significantly slower ascent rates than descent rates were found following deep foraging dives both during the day and night. Similar patterns were found for the Cuvier’s beaked whales. Our results suggest that so-called “bounce” dives do not serve a physiological function, although the slow ascents may. This Diel Variation in behavior suggests that beaked whales may spend less time in surface waters during the day to avoid
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Diel Variation in beaked whale diving behavior
Marine Mammal Science, 2008Co-Authors: Robin W. Baird, Daniel L. Webster, Gregory S. Schorr, Daniel J. Mcsweeney, Jay BarlowAbstract:We investigate Diel Variation in beaked whale diving behavior using data from time–depth recorders deployed on six Blainville’s (Mesoplodon densirostris) (255 h) and two Cuvier’s (Ziphius cavirostris) (34 h) beaked whales. Deep foraging dives (>800 m) occurred at similar rates during the day and night for Blainville’s beaked whales, and there were no significant Diel differences in ascent rates, descent rates, or mean or maximum depths or durations for deep dives. Dive to mid-water depths (100–600 m) occurred significantly more often during the day (mean = 1.59 h −1 ) than at night (mean = 0.26 h −1 ). Series of progressively shallower “bounce” dives were only documented to follow the deep, long dives made during the day; at night whales spent more time in shallow (
Daniel J Mennill - One of the best experts on this subject based on the ideXlab platform.
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Vocal behaviour of White-eared Ground-sparrows (Melozone leucotis) during the breeding season: repertoires, Diel Variation, behavioural contexts, and individual distinctiveness
Journal of Ornithology, 2016Co-Authors: Luis Sandoval, Carolina Mendez, Daniel J MennillAbstract:Gesangsverhalten von Weißohrammern ( Melozone leucotis ) während der Brutzeit: Repertoires, TagesVariation, Verhaltenskontext und individuelle Charakteristik Trotz des Vogelartenreichtums der Tropen und der großen Vielfalt an Lautäußerungen tropischer Vögel, gibt es verhältnismäßig wenige quantitativ-beschreibende Studien zu Vokalisation und Gesangsverhalten tropischer Vogelarten. Dieser Mangel an Informationen vermindert unser Verständnis tropischer Vögel, einschließlich der Fähigkeit, vergleichende Analysen zum Gesangsverhalten aus Sicht der Evolution durchzuführen. In dieser Studie präsentieren wir erstmals eine quantitative Beschreibung des Stimmenrepertoires und der täglichen Gesangsaktivität von Weißohrammern ( Melozone leucotis ) mittels gezielter und unabhängiger Aufnahmen, die in zwei aufeinander folgenden Brutsaisons in Costa Rica gesammelt wurden. Wir teilten die Lautäußerungen in Kategorien ein, um auf Basis des Aussehens der Klangspektrogramme eine Sammlung der Lautäußerungen für diese Art anzulegen. Weißohrammern erzeugen drei Hauptkategorien von Lautäußerungen: Sologesang, Rufe und Duette. Sologesänge werden ausschließlich von Männchen erzeugt. Jedes Männchen sang ein Repertoire aus Sologesangstypen, die alle die gleiche Grundstruktur hatten mit kurzen Einleitungstönen, einem frequenzmoduliertem Mittelteil und einem abschließendem Triller. Beide Geschlechter erzeugen Rufe und aufeinander abgestimmte Stimmduette. Wir quantifizierten Muster in der täglichen Variation der einzelnen Lautäußerungskategorien. Dabei konnten wir feststellen, dass Grundammern in der Morgendämmerung (zwischen 5:00 und 6:00) eine höhere Gesangs- und Stimmäußerungsleistung erbringen im Vergleich zum Rest des Tages. Mit Hilfe dieser Studie können die ersten Vergleiche von Lautäußerungen zwischen Weißohrammern und anderen nordamerikanischen Arten der Gattung Melozone angestellt werden, um sowohl Gemeinsamkeiten als auch Unterschiede zwischen den Artengruppen aufzuzeigen. Unsere Untersuchungen zeigen auch, dass Lautäußerungen im Zusammenhang mit der Kommunikation zwischen Brutpartnern und zur Revierverteidigung (Rufe und Duette) ein geringeres Maß an individueller Charakteristik aufweisen, als solche, die vor allem der Weibchenanwerbung (Sologesänge der Männchen) dienen. Unsere Beobachtungen lassen erkennen, dass jeder der drei Lautäußerungstypen verschiedene Funktionen bei Weißohrammern hat, was wiederum darauf hin deutet, dass das kleine Stimmenrepertoire eines tropischen Singvogels diverse Kommunikationsfunktionen haben kann. There are relatively few quantitative descriptive studies of the vocalisations and vocal behaviour of tropical bird species, in spite of the tropic’s rich avian biodiversity and the extensive variety of vocalisations produced by tropical birds. This lack of information inhibits our understanding of tropical animals, including our ability to perform comparative analyses on vocal behaviours from an evolutionary perspective. In this study, we present the first quantitative description of the vocal repertoire and daily vocal activity of White-eared Ground-sparrows ( Melozone leucotis ), using focal and autonomous recordings collected during two consecutive breeding seasons in Costa Rica. We classified vocalisations into categories based on their visual appearance on sound spectrograms to create a library of vocalisations for this species. We found that White-eared Ground-sparrows produce three main categories of vocalisations: solo songs, calls, and duets. Solo songs were produced only by males. Each male sang a repertoire of solo song types, which all shared the same general structure with short introductory notes, a frequency-modulated middle section, and a terminal trill. Both sexes produce calls and coordinated vocal duets. We quantified patterns of Diel Variation in each category of vocalisation, and found that the Ground-sparrows produced all three vocalisations at higher output at dawn (between 0500 and 0600 hours) compared to the rest of the day. This study allowed us to conduct the first comparisons of vocalisations between White-eared Ground-sparrows and North American species in the genus Melozone , and revealed both similarities and differences between the species groups. Our investigation also showed that vocalisations related to communication within pairs and to territory defence (calls and duets) exhibited lower levels of individual distinctiveness than vocalisations related mainly to female attraction (male solo songs). Our observations suggest that each of the three types of vocalisations have multiple functions in White-eared Ground-sparrows, revealing diverse communication functions with a small vocal repertoire in this tropical songbird.
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vocal behaviour of white eared ground sparrows melozone leucotis during the breeding season repertoires Diel Variation behavioural contexts and individual distinctiveness
Journal of Ornithology, 2016Co-Authors: Carolina Mendez, Luis Sandoval, Daniel J MennillAbstract:There are relatively few quantitative descriptive studies of the vocalisations and vocal behaviour of tropical bird species, in spite of the tropic’s rich avian biodiversity and the extensive variety of vocalisations produced by tropical birds. This lack of information inhibits our understanding of tropical animals, including our ability to perform comparative analyses on vocal behaviours from an evolutionary perspective. In this study, we present the first quantitative description of the vocal repertoire and daily vocal activity of White-eared Ground-sparrows (Melozone leucotis), using focal and autonomous recordings collected during two consecutive breeding seasons in Costa Rica. We classified vocalisations into categories based on their visual appearance on sound spectrograms to create a library of vocalisations for this species. We found that White-eared Ground-sparrows produce three main categories of vocalisations: solo songs, calls, and duets. Solo songs were produced only by males. Each male sang a repertoire of solo song types, which all shared the same general structure with short introductory notes, a frequency-modulated middle section, and a terminal trill. Both sexes produce calls and coordinated vocal duets. We quantified patterns of Diel Variation in each category of vocalisation, and found that the Ground-sparrows produced all three vocalisations at higher output at dawn (between 0500 and 0600 hours) compared to the rest of the day. This study allowed us to conduct the first comparisons of vocalisations between White-eared Ground-sparrows and North American species in the genus Melozone, and revealed both similarities and differences between the species groups. Our investigation also showed that vocalisations related to communication within pairs and to territory defence (calls and duets) exhibited lower levels of individual distinctiveness than vocalisations related mainly to female attraction (male solo songs). Our observations suggest that each of the three types of vocalisations have multiple functions in White-eared Ground-sparrows, revealing diverse communication functions with a small vocal repertoire in this tropical songbird.
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the vocal behavior of the brown throated wren troglodytes brunneicollis song structure repertoires sharing syntax and Diel Variation
Journal of Ornithology, 2014Co-Authors: Roberto J Sosalopez, Daniel J MennillAbstract:Empirical descriptions of vocal behaviour are important for understanding avian biology. In this study, we provide the first detailed analysis of the vocal behaviour of the Brown-throated Wren (Troglodytes brunneicollis), a neotropical songbird found in oak forests in the highlands of Mexico and the southwestern United States. We quantify the fine structural characteristics of the song, and describe the size and structure of the song repertoire. Further, we describe Diel Variation, analyze song-sharing patterns among neighbors, and explore whether this species uses syntactical rules for creating their songs. Our analyses reveal that Brown-throated Wrens have complex songs and simple calls. They sing with eventual variety, repeating songs many times before switching to a new song type. Males combine syllables into phrases to create songs. We show that song repertoire size is not fixed; birds recombine their syllables to produce highly variable song types. Brown-throated Wrens sing with high vocal output after sunrise and song activity declines throughout the morning. Song sharing shows no Variation with distance among our sampled individuals. We divide the syllables in Brown-throated Wren songs into 13 categories; birds sing some syllables more frequently than others, and some syllables are more likely to be found at the beginning, middle, or end of the song. Transitions between syllable categories deviate significantly from random chance, and most males analyzed follow similar patterns of syllable transitions, revealing syntactical structure. This research, which provides the first empirical study of Brown-throated Wren song, expands our knowledge of the behaviour of this poorly-studied taxon, and contributes insight into the organization and composition of song in tropical birds.
Daniel J. Mcsweeney - One of the best experts on this subject based on the ideXlab platform.
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Diel Variation in beaked whale diving behavior
Marine Mammal Science, 2008Co-Authors: Robin W. Baird, Daniel L. Webster, Gregory S. Schorr, Daniel J. Mcsweeney, Jay BarlowAbstract:We investigate Diel Variation in beaked whale diving behavior using data from time–depth recorders deployed on six Blainville’s (Mesoplodon densirostris) (255 h) and two Cuvier’s (Ziphius cavirostris) (34 h) beaked whales. Deep foraging dives (>800 m) occurred at similar rates during the day and night for Blainville’s beaked whales, and there were no significant Diel differences in ascent rates, descent rates, or mean or maximum depths or durations for deep dives. Dive to mid-water depths (100–600 m) occurred significantly more often during the day (mean = 1.59 h −1 ) than at night (mean = 0.26 h −1 ). Series of progressively shallower “bounce” dives were only documented to follow the deep, long dives made during the day; at night whales spent more time in shallow (<100 m) depths. Significantly slower ascent rates than descent rates were found following deep foraging dives both during the day and night. Similar patterns were found for the Cuvier’s beaked whales. Our results suggest that so-called “bounce” dives do not serve a physiological function, although the slow ascents may. This Diel Variation in behavior suggests that beaked whales may spend less time in surface waters during the day to avoid
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Diel Variation in beaked whale diving behavior
Marine Mammal Science, 2008Co-Authors: Robin W. Baird, Daniel L. Webster, Gregory S. Schorr, Daniel J. Mcsweeney, Jay BarlowAbstract:We investigate Diel Variation in beaked whale diving behavior using data from time–depth recorders deployed on six Blainville’s (Mesoplodon densirostris) (255 h) and two Cuvier’s (Ziphius cavirostris) (34 h) beaked whales. Deep foraging dives (>800 m) occurred at similar rates during the day and night for Blainville’s beaked whales, and there were no significant Diel differences in ascent rates, descent rates, or mean or maximum depths or durations for deep dives. Dive to mid-water depths (100–600 m) occurred significantly more often during the day (mean = 1.59 h −1 ) than at night (mean = 0.26 h −1 ). Series of progressively shallower “bounce” dives were only documented to follow the deep, long dives made during the day; at night whales spent more time in shallow (