Elephant Seal Movements: Dive Types and Their Sequences

• Main Authors: David R. Brillinger, Brent S. Stewart
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: Elephant Seal; Elephant Seals
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.52.3141; http://stat-www.berkeley.edu/pub/users/brill/Papers/nantucket.ps

This paper is concerned with time-depth curves recorded for northern elephant seals that are migrating. The curves show a succession of dives of varying depths, durations and types. A mixture model is employed to estimate the various curves present. An advantage of this procedure, over the ones that have been employed, is that it is automatic. Further a categoricalvalued series is developed for the sequence of dives. It is examined for evidence of independence for both dives of one type and amongst dives of different types. Key words and phrases: Categorical-valued time series, dive patterns, elephant seals, foraging behavior, longitudinal data; mixture model. AMS 1991 subject classifications: Primary 62M10; 62M15; 62P10. 1 Introduction Studies of the foraging behaviors of a variety of marine vertebrates (eg. seals, sea lions, penguins, sea birds, sea turtles) have been conducted in recent years using micro-processor controlled event recorders to document diving patterns. The data ge.