• Login
    View Item 
    •   Home
    • UA Graduate and Undergraduate Research
    • UA Theses and Dissertations
    • Dissertations
    • View Item
    •   Home
    • UA Graduate and Undergraduate Research
    • UA Theses and Dissertations
    • Dissertations
    • View Item
    JavaScript is disabled for your browser. Some features of this site may not work without it.

    Browse

    All of UA Campus RepositoryCommunitiesTitleAuthorsIssue DateSubmit DateSubjectsPublisherJournalThis CollectionTitleAuthorsIssue DateSubmit DateSubjectsPublisherJournal

    My Account

    LoginRegister

    About

    AboutUA Faculty PublicationsUA DissertationsUA Master's ThesesUA Honors ThesesUA PressUA YearbooksUA CatalogsUA Libraries

    Statistics

    Most Popular ItemsStatistics by CountryMost Popular Authors

    Behavior and occurrence patterns, feeding ecology, and life history of dusky dolphins (Lagenorhynchus obscurus) off Kaikoura, New Zealand.

    • CSV
    • RefMan
    • EndNote
    • BibTex
    • RefWorks
    Thumbnail
    Name:
    azu_td_9310605_sip1_m.pdf
    Size:
    6.665Mb
    Format:
    PDF
    Description:
    azu_td_9310605_sip1_m.pdf
    Download
    Author
    Cipriano, Frank Walter.
    Issue Date
    1992
    Keywords
    Dusky dolphins -- New Zealand -- Kaikoura.
    Dusky dolphins -- New Zealand -- Ecology.
    Dusky dolphins -- New Zealand -- Behavior.
    Dusky dolphins -- New Zealand -- Geographical distribution.
    Dolphins -- New Zealand.
    Committee Chair
    Thomson, Donald A.
    
    Metadata
    Show full item record
    Publisher
    The University of Arizona.
    Rights
    Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.
    Abstract
    My dissertation research focused on the behavior, movement patterns, and foraging ecology of dusky dolphins (Lagenorhynchus obscurus) off the east coast of New Zealand's South Island. Information on growth, morphometrics, parasites and life history was also collected. Movement patterns and foraging behavior of New Zealand dusky dolphins were much different from those of dusky dolphins observed off the Argentine coast by Bernd Wursig, the only other study of dusky dolphin behavior. Unlike the Argentine dolphins, which cooperatively herd anchovy to the surface and contain them there for feeding, New Zealand dusky dolphins behave and forage more like Hawaiian spinner dolphins (Stenella longirostris). In summer and fall, New Zealand dusky dolphins remain near shore in morning and early afternoon hours, then move into deeper water with greatly increased activity levels in late afternoon. In winter and spring they remain farther from shore at all times of day, are found in somewhat larger groups, and appear to travel along shore more often than in other seasons. In summer, dive times of radio-tagged dolphins also varied on a daily cycle, most long dives occurring during crepuscular and night periods. Stomach contents of incidentally-netted and beachcast dolphins contained primarily a demersal fish and a few types of mesopelagic fishes and squid. Acoustic surveys along the east coast of South Island show a dense layer of mesopelagic fishes and squid that move to within 50-100 m of the surface at night. Like Hawaiian spinners, New Zealand dusky dolphins feed primarily on prey in and associated with the vertically migrating layer, probably as a means of increasing foraging efficiency. External measurements of L. obscurus specimens were analyzed using canonical variate analysis, which revealed measurements useful in discrimination of age/sex classes, including dorsal fin dimensions, and positioning of dorsal fin and flipper insertions. Tooth-section age analysis of specimens allowed construction of growth curves; life span maximum was about 35 years. The very large size of active testes (over 1 kg each) during summer breeding represents a large proportion of total body weight. Along with observations of group composition variability, this suggests a promiscuous mating system and a fluid, extended-group social system.
    Type
    text
    Dissertation-Reproduction (electronic)
    Degree Name
    Ph.D.
    Degree Level
    doctoral
    Degree Program
    Ecology & Evolutionary Biology
    Graduate College
    Degree Grantor
    University of Arizona
    Collections
    Dissertations

    entitlement

     

    Related items

    Showing items related by title, author, creator and subject.

    • Thumbnail

      Reliability of Bone Gelatin AMS Dating: Rattus exulans and Marine Shell Radiocarbon Dates from Pauatahanui Midden Sites in Wellington, New Zealand

      Athfield, Nancy Beavan; McFadgen, Bruce; Sparks, Rodger (Department of Geosciences, The University of Arizona, 1999-01-01)
      A suite of 6 bone gelatin accelerator mass spectrometry (AMS) radiocarbon dates for Rattus exulans Peale and associated beta decay 14C dates for Austrovenus stutchburyi shell are presented for 4 middens at Pauatahanui, Wellington, New Zealand. Mean calibrated age ranges of Rattus exulans (520-435 BP and 350-330 BP at 95% confidence level) and shell (465-375 BP at 95% confidence level) from the 4 midden sites overlap. The agreement between Rattus exulans bone gelatin dates and associated shell provides an inter-sample comparison of 14C dating using both gas counting (beta decay) and AMS dating techniques. We examine the adequacy of the standard gelatinization treatment for bone samples, which has been employed consistently at the laboratory since 1995.
    • Thumbnail

      PHAT. XIX. The Ancient Star Formation History of the M31 Disk

      Williams, Benjamin F.; Dolphin, Andrew E.; Dalcanton, Julianne J.; Weisz, Daniel R.; Bell, Eric F.; Lewis, Alexia R.; Rosenfield, Philip; Choi, Yumi; Skillman, Evan; Monachesi, Antonela; et al. (IOP PUBLISHING LTD, 2017-09-12)
      We map the star formation history across M31 by fitting stellar evolution models to color-magnitude diagrams of each 83 '' x 83 '' (0.3 x 1.4 kpc, deprojected) region of the Panchromatic Hubble Andromeda Treasury (PHAT) survey outside of the innermost 6' x 12' portion. We find that most of the star formation occurred prior to similar to 8 Gyr ago, followed by a relatively quiescent period until similar to 4 Gyr ago, a subsequent star formation episode about 2 Gyr ago, and a return to relative quiescence. There appears to be little, if any, structure visible for populations with ages older than 2 Gyr, suggesting significant mixing since that epoch. Finally, assuming a Kroupa initial mass function from 0.1 to 100 M-circle dot, we find that the total amount of star formation over the past 14 Gyr in the area over which we have fit models is 5 x 10(10) M-circle dot. Fitting the radial distribution of this star formation and assuming azimuthal symmetry, (1.5 +/- 0.2). x 10(11) M-circle dot of stars has formed in the M31 disk as a whole, (9 +/- 2) x 10(10). M-circle dot of which has likely survived to the present after accounting for evolutionary effects. This mass is about one-fifth of the total dynamical mass of M31.
    • Thumbnail

      The Enigmatic (Almost) Dark Galaxy Coma P: Distance Measurement and Stellar Populations from HST Imaging

      Brunker, Samantha W.; McQuinn, Kristen B. W.; Salzer, John J.; Cannon, John M.; Janowiecki, Steven; Leisman, Lukas; Rhode, Katherine L.; Adams, Elizabeth A. K.; Ball, Catherine; Dolphin, Andrew E.; et al. (IOP PUBLISHING LTD, 2019-02)
      We present Hubble Space Telescope (HST) observations of the low surface brightness (SB) galaxy Coma P. This system was first discovered in the Arecibo Legacy Fast ALFA H I survey and was cataloged as an (almost) dark galaxy because it did not exhibit any obvious optical counterpart in the available survey data (e.g., Sloan Digital Sky Survey). Subsequent WIYN pODI imaging revealed an ultra-low SB stellar component located at the center of the H I detection. We use the HST images to produce a deep color-magnitude diagram of the resolved stellar population present in Coma P. We clearly detect a red stellar sequence that we interpret to be a red giant branch and use it to infer a tip of the red giant branch distance of 5.50(-0.53)(+0.28) Mpc. The new distance is substantially lower than earlier estimates and shows that Coma P is an extreme dwarf galaxy. Our derived stellar mass is only 4.3 x 10(5) M-circle dot, meaning that Coma P has an extreme H I-to-stellar mass ratio of 81. We present a detailed analysis of the galaxy environment within which Coma P resides. We hypothesize that Coma P formed within a local void and has spent most of its lifetime in a low-density environment. Over time, the gravitational attraction of the galaxies located in the void wall has moved it to the edge, where it had a recent "fly-by" interaction with M64. We investigate the possibility that Coma P is at a farther distance and conclude that the available data are best fit by a distance of 5.5 Mpc.
    The University of Arizona Libraries | 1510 E. University Blvd. | Tucson, AZ 85721-0055
    Tel 520-621-6442 | repository@u.library.arizona.edu
    DSpace software copyright © 2002-2017  DuraSpace
    Quick Guide | Contact Us | Send Feedback
    Open Repository is a service operated by 
    Atmire NV
     

    Export search results

    The export option will allow you to export the current search results of the entered query to a file. Different formats are available for download. To export the items, click on the button corresponding with the preferred download format.

    By default, clicking on the export buttons will result in a download of the allowed maximum amount of items.

    To select a subset of the search results, click "Selective Export" button and make a selection of the items you want to export. The amount of items that can be exported at once is similarly restricted as the full export.

    After making a selection, click one of the export format buttons. The amount of items that will be exported is indicated in the bubble next to export format.