84
seconds to several minutes, depending on the size of the study area and the amount of individuals present, because in practice, the observation, classification, and recording of a
behavior state takes time.
“Survey”: individuals or groups are observed for a period of time, the number of animals, behavior, and location are recorded, providing information about demographic,
reproductive and ecological factors (Mann 1999), mean and range of group sizes patterns
(Mann 2000). It might serve as a kind of census. In order to properly characterize the
groups, a survey can lasts longer because of the diving, swimming and sometimes cryptic
behavior of target animals.
“Behaviour sampling”: a whole group of subjects is under observation and just the
occurrence of some behaviors is registered. It is basically used to record rare and significant
behaviors (Martin and Bateson 1993).
It is often possible to use more than one sampling method in a study (Altmann
1974), actually, that is practical and advisable (Mann 2000). Also, adaptation and
adequacies of methods must be made to fit research goals in the context of the target
species. However, investigators should always minimize the biases inherent in different methods (Mann 2000), should recognize the limitations of their sample,
methods and statistical inferences (Bart et al. 1998). If methods used to observe
animals remain the same and sightability remains reasonably constant, comparisons
among years should be valid (Salden 1988).
4.2.4 Preliminary Observations, Pilot Study, Protocol
A period of informal observation with quantitative recordings of behavior, aimed to
understand and describe both, the species and the behavior intended to be measured,
should preced an effective data collection. The preliminary observation provides the
raw material for formulating hypothesis and also for choosing the most suitable
recording method (Martin and Bateson 1993). The development of a protocol,
describing all daily activities and procedures, the way equipment should be prepared, how to observe animals, the manner to register the data, how to summarize
and tabulate data, etc., benefits and organize the research. Thus, a pilot study is
recommended in order to build the ethogram, to test the observational protocol and
to verify if the methods are adequate to reach the desired goals.
4.2.5 Ethogram
A comprehensive repertoire of the target species behavior is the first step in any
behavioral study. It is crucial to extensively observe the animals in order to create a
complete ethogram, which must be mutually exclusive and cumulative inclusive,
i.e., each described behavior cannot include any other, nor give chance for misunderstanding among them, comprising all animal’s behavioral events and behavioral
states (as described by Altmann 1974: behavioral events are brief, short durations
M.E. Morete et al.
seconds to several minutes, depending on the size of the study area and the amount of individuals present, because in practice, the observation, classification, and recording of a
behavior state takes time.
“Survey”: individuals or groups are observed for a period of time, the number of animals, behavior, and location are recorded, providing information about demographic,
reproductive and ecological factors (Mann 1999), mean and range of group sizes patterns
(Mann 2000). It might serve as a kind of census. In order to properly characterize the
groups, a survey can lasts longer because of the diving, swimming and sometimes cryptic
behavior of target animals.
“Behaviour sampling”: a whole group of subjects is under observation and just the
occurrence of some behaviors is registered. It is basically used to record rare and significant
behaviors (Martin and Bateson 1993).
It is often possible to use more than one sampling method in a study (Altmann
1974), actually, that is practical and advisable (Mann 2000). Also, adaptation and
adequacies of methods must be made to fit research goals in the context of the target
species. However, investigators should always minimize the biases inherent in different methods (Mann 2000), should recognize the limitations of their sample,
methods and statistical inferences (Bart et al. 1998). If methods used to observe
animals remain the same and sightability remains reasonably constant, comparisons
among years should be valid (Salden 1988).
4.2.4 Preliminary Observations, Pilot Study, Protocol
A period of informal observation with quantitative recordings of behavior, aimed to
understand and describe both, the species and the behavior intended to be measured,
should preced an effective data collection. The preliminary observation provides the
raw material for formulating hypothesis and also for choosing the most suitable
recording method (Martin and Bateson 1993). The development of a protocol,
describing all daily activities and procedures, the way equipment should be prepared, how to observe animals, the manner to register the data, how to summarize
and tabulate data, etc., benefits and organize the research. Thus, a pilot study is
recommended in order to build the ethogram, to test the observational protocol and
to verify if the methods are adequate to reach the desired goals.
4.2.5 Ethogram
A comprehensive repertoire of the target species behavior is the first step in any
behavioral study. It is crucial to extensively observe the animals in order to create a
complete ethogram, which must be mutually exclusive and cumulative inclusive,
i.e., each described behavior cannot include any other, nor give chance for misunderstanding among them, comprising all animal’s behavioral events and behavioral
states (as described by Altmann 1974: behavioral events are brief, short durations
M.E. Morete et al.