Sensor:
Natural Mark

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Name
Natural Mark
External ID
natural-mark
Is Location Sensor
true

Search Results

Now showing 1 - 2 of 2
  • Data package
    Data from: Monthly variations in feeding and activity patterns of the mangabey, Cercocebus albigena (Lydekker)
    (2016-03-23) Waser, Peter M.
    Ranging patterns, feeding activity, and time budgets of a group of gray-cheeked mangabeys in the Kibale Forest, western Uganda, were studied in May-June 1971 and from March 1972 to April 1973. Locations and activities of individuals in a fifteen-member group of this arboreal primate were systematically recorded at half-hourly intervals during continuous following of the group. Phenological data were concurrently collected for eleven species of intensively used trees. Mangabeys are primarily frugivores, although leaves and flowers of some species are eaten and substantial time was devoted to insect foraging. Although a typical twice-yearly alternation of wet and dry periods exists in this forest, strongly seasonal trends are the exception in the following aspects of mangabey behaviour: (1) extent and location of areas used, (2) distance moved daily, (3) percentage of time spent feeding or moving, (4) percentage of time spent feeding on different food types. An explanation may be provided by the phenological data, which indicate that many species of tree used by mangabeys fruit either asynchronously and nonseasonally or synchronously but at very long and possibly irregular intervals. Thus mangabeys are faced with foods which fluctuate widely in availability, particularly within a small area, but which are not seasonal in their fluctuations.
  • Data package
    Data from: Direction matching for sparse movement datasets: determining interaction rules in social groups
    (2017-01-03) Bonnell, Tyler R.; Dostie, Marcus; Clarke, Parry M.; Henzi, S. Peter; Barrett, Louise
    It is generally assumed that high-resolution movement data are needed to extract meaningful decision-making patterns of animals on the move. Here we propose a modified version of force matching (referred to here as direction matching), whereby sparse movement data (i.e., collected over minutes instead of seconds) can be used to test hypothesized forces acting on a focal animal based on their ability to explain observed movement. We first test the direction matching approach using simulated data from an agent-based model, and then go on to apply it to a sparse movement data set collected on a troop of baboons in the DeHoop Nature Reserve, South Africa. We use the baboon data set to test the hypothesis that an individual’s motion is influenced by the group as a whole or, alternatively, whether it is influenced by the location of specific individuals within the group. Our data provide support for both hypotheses, with stronger support for the latter. The focal animal showed consistent patterns of movement toward particular individuals when distance from these individuals increased beyond 5.6 m. Although the focal animal was also sensitive to the group movement on those occasions when the group as a whole was highly clustered, these conditions of isolation occurred infrequently. We suggest that specific social interactions may thus drive overall group cohesion. The results of the direction matching approach suggest that relatively sparse data, with low technical and economic costs, can be used to test between hypotheses on the factors driving movement decisions.