82
4.2.1 Land-Base Station Aspects and Limitations
Studies from land-station, frequently suffer from limited geographic coverage and represent a small part of the species distribution, so it is necessary to treat the collected data
with caution. Does the sampled area show what is observed in the entire distribution of
the animals? What inferences can be derived from the data? Normally, because of the
elevation of the land-based station, it is almost impossible to recognize individuals,
except if the animal shows very conspicuous and uncommon marks. For this reason, it
is important to note the possibility of the same individual being sampled more than once.
Besides, animals that are farther away are less likely to be detected than those closer to
shore, causing a skewed view of the actual distribution (Arranz et al. 2014). All these
aspects and limitations should be taken into account. Scientists deal with these issues in
a variety of ways, from time and spacing of sampling (e.g., Baker et al. 1982; Smultea
1994; Frankel and Clark 2002), up to the development of statistical models that allow
the use of such data (Bart et al. 1998; Quinn and Keough 2002; Zuur et al. 2007, 2010).
4.2.2 Land-Base Station Spot and Tips
Not only the relatively close presence of the target species is relevant prior to defining the land-station spot; it is important to get some information about the locale. If
the chosen place is inside a protected area, perhaps, special permits are necessary;
if it is in a public area, gather information about the security of the place; also verify
the possible occurrence of dangerous and poison animals. Likewise, it is pertinent
to verify if the team presence won’t jeopardized other animals’ activities and behaviors, for example, nesting birds. Thus, there should be precautionary measures and
the team should be aware of procedures to leave the area in case of any emergency.
Normally LBS are in open areas, without edifications, or constructions. Some
kind of umbrella or tent, to protect from straight sunlight is advised. As environmental conditions may change suddenly, it is important to have some infrastructure
to protect the team and the equipment when weather gets rough, as waterproof
boxes, cases and proper clothes for protection against winds and cold.
The higher the land station the broader the field of view thus the study area.
Although, it should not be too elevated spoiling the capacity of observations. If
more than one observer will collect the data, or if observers will alternate functions
within the study period, they should receive the same training by the same person to
avoid inter-observers variations in data collection.
4.2.3 Land-Based Station Sampling Methods
Land-based station, as a platform to study animals without interference of observers
on their behavior, enables the application of diverse methods. In face of the characteristic of the species studied, according to the research questions and the number of
M.E. Morete et al.
4.2.1 Land-Base Station Aspects and Limitations
Studies from land-station, frequently suffer from limited geographic coverage and represent a small part of the species distribution, so it is necessary to treat the collected data
with caution. Does the sampled area show what is observed in the entire distribution of
the animals? What inferences can be derived from the data? Normally, because of the
elevation of the land-based station, it is almost impossible to recognize individuals,
except if the animal shows very conspicuous and uncommon marks. For this reason, it
is important to note the possibility of the same individual being sampled more than once.
Besides, animals that are farther away are less likely to be detected than those closer to
shore, causing a skewed view of the actual distribution (Arranz et al. 2014). All these
aspects and limitations should be taken into account. Scientists deal with these issues in
a variety of ways, from time and spacing of sampling (e.g., Baker et al. 1982; Smultea
1994; Frankel and Clark 2002), up to the development of statistical models that allow
the use of such data (Bart et al. 1998; Quinn and Keough 2002; Zuur et al. 2007, 2010).
4.2.2 Land-Base Station Spot and Tips
Not only the relatively close presence of the target species is relevant prior to defining the land-station spot; it is important to get some information about the locale. If
the chosen place is inside a protected area, perhaps, special permits are necessary;
if it is in a public area, gather information about the security of the place; also verify
the possible occurrence of dangerous and poison animals. Likewise, it is pertinent
to verify if the team presence won’t jeopardized other animals’ activities and behaviors, for example, nesting birds. Thus, there should be precautionary measures and
the team should be aware of procedures to leave the area in case of any emergency.
Normally LBS are in open areas, without edifications, or constructions. Some
kind of umbrella or tent, to protect from straight sunlight is advised. As environmental conditions may change suddenly, it is important to have some infrastructure
to protect the team and the equipment when weather gets rough, as waterproof
boxes, cases and proper clothes for protection against winds and cold.
The higher the land station the broader the field of view thus the study area.
Although, it should not be too elevated spoiling the capacity of observations. If
more than one observer will collect the data, or if observers will alternate functions
within the study period, they should receive the same training by the same person to
avoid inter-observers variations in data collection.
4.2.3 Land-Based Station Sampling Methods
Land-based station, as a platform to study animals without interference of observers
on their behavior, enables the application of diverse methods. In face of the characteristic of the species studied, according to the research questions and the number of
M.E. Morete et al.