Observational studies
To assess learning from an observational perspective, we must analyze
how an animal behaves at a given time based on local conditions and past
experiences. In practice observational studies typically record the
location of animals and thus their experiences over relatively long
time-frames (e.g., multiple years, or entire lifetime). Remotely sensed
geographic and climatological data then provide the local conditions the
animal is experiencing during movement. Additional information on the
behavioral and physiological states of the animal may also be relevant.
Fortunately, the ongoing evolution in remote animal tracking and sensing
technology means that we are increasingly able to measure physiological
and behavioural states over long periods of time (Kays et al .
2015).
Data on repeated movement patterns can help us differentiate between
hypotheses about learning. For example, data on repeated migration
routes has been used to determine whether animals follow resource
gradients, rely on memory to navigate, or learn from experience to shape
their movement decisions (Mueller et al . 2013, Merkle et
a l. 2019). However, long-term tracking data may also be sufficient for
analysis. For example, long-term data tracking the movement of wolves
has been use to determine whether animals only follow resource levels,
or also rely on the memory of time since last visit to a location
(Schlägel et al. 2017). Augmenting tracking data with direct data
on the information that the animals might gather, for example the
location of kill sites (Gurarie et al . 2011) or profitable forage
patches (Merkle et al . 2014), can further enhance our
understanding of how animals monitor their environment through time
(Gurarieet al. 2011).
Comparative studies can be useful for identifying instances of learning.
For example, comparing the movement efficiency of juveniles and adults
shows that seabirds start by exploring their landscape and then learn to
identify the good foraging areas and cues as adults
(de
Grissac et al. 2017; Votier et al. 2017; Grecian et
al. 2018; Wakefield et al. 2019). Effects of early-life
experience can also be identified by analyzing the site fidelity of
animals to their breeding ground
(Weinrich
1998) and by comparing the migration patterns of offspring to those of
their mother’s
(Colbecket al. 2013). Finally, comparing the movement of cultural groups,
especially if sympatric, can help to assess the effect of culturally
transmitted information on animals’ use of space
(Kendalet al. 2018; Owen et al. 2019).