Context-dependent dispersal, public information, and heterospecific attraction in newts
Dispersal is one of the main processes that determine community structure. Individuals make dispersal decisions according to environmental and/or social cues that reflect the fitness prospects in a given patch. The presence and abundance of heterospecifics within the same ecological guild, and/or their breeding success, may act as public information that influences movement decisions. To date, most studies investigating the role of heterospecific attraction have focused on habitat choice, using both experimental and correlational approaches. The present study is the first to examine how long-term variation in heterospecific density in breeding patches may affect dispersal patterns in spatially structured populations. We investigate how the dispersal decisions of the great crested newt (Triturus cristatus) are related to the variable density of two other newt species, the alpine newt (Ichthyosaura alpestris) and the palmate newt (Lissotriton helveticus). To examine this issue, we used capture–recapture data collected in an experimental pond network over a 20-year period. The results revealed that the great crested newt’s dispersal is context dependent and is affected by variation in heterospecific density: individuals were less likely to emigrate from ponds with high heterospecific density and were more likely to immigrate to ponds with high heterospecific density. These findings suggest that individuals adjust their dispersal decisions at least partly based on public information provided by heterospecifics. This mechanism may play a critical role in the dynamics of spatially structured populations and community functioning.
KeywordsDispersal Heterospecific attraction Public information Triturus cristatus Ichthyosaura alpestris Lissotriton helveticus
This research program was supported by the Institut Universitaire de France (IUF). The Pierre Vérots Foundation made the long-term monitoring possible by providing the use of a protected area free of intensive agriculture. The Foundation also contributed to the creation of the ponds and the maintenance of the surrounding meadows, as well as providing technical support for newt capture. Furthermore, it provided a well-equipped laboratory, making it possible to mark and measure the newts on site, thus reducing animal stress. We would especially like to thank Benoît Castanier, Jean-Philippe Rabatel and Charles Granat for their valuable assistance. We are also grateful to the Rhône-Alpes region for providing funding for the marking equipment. We would like to warmly thank the numerous students who helped us with the fieldwork, as well as Adeline Dumet and Vanessa Gardette for their assistance.
Author contribution statement
HC performed modeling and has written the first draft of the manuscript. OG has been in charge of the technical support of the monitoring. PJ has initiated and supervised the monitoring and its exploitation.
- Bonte D, Van Dyck H, Bullock JM, Coulon A, Delgado M, Gibbs M, Lehouck V, Matthysen E, Mustin K, Saastamoinen M, Schtickzelle N, Stevens VM, Vandewoestijne S, Baguette M, Barton K, Benton TG, Chaput-Bardy A, Clobert J, Dytham C, Hovestadt T, Meier CM, Palmer SCF, Turlure C, Travis JMJ (2012) Costs of dispersal. Biol Rev 87:290–312CrossRefGoogle Scholar
- Braz E, Joly P (1993) Micro-habitat use, resource partitioning and ecological succession in a size-structured guild of newt larvae (g. Triturus, Caudata, Amphibia). Archiv Hydrobiol 131:129–139Google Scholar
- Fasola M, Canova L (1992) Feeding habits of Triturus vulgaris, T. cristatus and T. alpestris (Amphibia, Urodela) in the northern apennines (Italy). Ital J Zool 59:273–280Google Scholar
- Joly P, Miaud C (1993) How does a newt find its pond: the role of chemical cues in migrating alpine newt. Ethol Ecol Evol 5:447–455Google Scholar
- Martin E, Caillère L (1982) Local enhancement in the Alpine newt, Triturus alpestris (Amphibia, Urodela) in aquatic phase. CR Biol 294:1105–1108Google Scholar
- Stamps J (2001) Habitat selection by dispersers: integrating proximate and ultimate approaches. In: Clobert J, Danchin E, Dhondt A, Nichols J (eds) Dispersal. Oxford University Press, Oxford, pp 230–242Google Scholar