Behavioural decisions are often context-dependent, where information from immediate experience is incorporated into an individual’s decision-making, particularly in complex environments. To test whether such mechanism is adopted by foragers in heterogeneous environments, we investigated the foraging behaviour of the deposit-feeding sand-bubbler crab, Scopimera intermedia. An individual-based model was constructed, based on an optimal-patch selection criterion, which implicitly assumed that individuals adjust foraging decisions based on immediate past experience. The model’s predictions were tested on the shore by manipulating the location of food patches, where the crab showed a strong context-dependent foraging pattern. When resources were randomly distributed, the crab responded by spending 56% of time in enriched patches compared with only 28% in the same area when patches were composed of natural sediments. Shore manipulations varying resource distribution supported the underlying principles of the model mechanism, and highlighted the benefits of such a strategy in heterogeneous environments such as intertidal sediments where food resources vary at different spatial and temporal scales. The proposed model therefore provides a mechanistic process, based on optimal foraging, to predict foraging decisions and movement patterns of animals feeding in heterogeneous landscapes.
|Number of pages||9|
|Journal||Proceedings of the Royal Society B: Biological Sciences|
|Early online date||30 Aug 2017|
|Publication status||Published - 30 Aug 2017|
This research was supported by a HKU Postgraduate Scholarship to T.Y.H.
We thank HKU Hard Rock Ecology lab members and Dr Giacomo Santini (University of Florence, Italy) for providing comments on earlier drafts of the manuscript. We thank Burt P. Kotler and an anonymous referee for providing valuable comments during the reviewing process.
- Individual-based model
- Intertidal sediments
- Optimal foraging
- Reference window