ABSTRACT
The ability to be faithful to a particular area or site was analysed in the shanny Lipophrys pholis. Using passive integrated transponders, adults from a population of L. pholis at Cabo Raso, Portugal, were followed over a period of 3 years. The findings showed that site fidelity is a consistent behaviour during the breeding season with specific breeding males being found only in particular sectors within the area, and in specific nests throughout the years. The fact that, in general, L. pholis individuals were absent from the study area during the non-breeding season and breeding males were recorded returning to the same nests and sectors for consecutive breeding seasons suggests that they have developed excellent homing abilities. Translocation data corroborate this idea showing that breeding males successfully returned to their nests after a displacement of >100 m. Altogether, these findings highlight the relevance of life-history traits (e.g. nesting) in the conditioning of site fidelity and homing for this species of rocky intertidal fish, and more importantly, provide evidence for the need of a well-developed navigational system.
Subject(s)
Homing Behavior/physiology , Nesting Behavior/physiology , Perciformes/physiology , Animal Migration , Animals , Atlantic Ocean , Breeding , Male , Portugal , SeasonsABSTRACT
Although navigation is common in many animals, only a few perform true navigation, meaning that they have the ability to return to a given place by relying on indirect cues obtained at the release site (i.e., by relying on information from a "map and compass" mechanism). The common intertidal fish, Lipophrys pholis, is thought to have homing abilities through a mechanism that primarily makes use of familiar landmarks (i.e., piloting). Anecdotal reports that individuals return to their home pools after release at unfamiliar sites suggest that L. pholis might use cues collected at the release site to find their way back (i.e., they might use map and compass information). Using a completely artificial setup, we tested the homing abilities of L. pholis as a function of age, sex, and familiarity with the release site. The findings showed that motivation for homing is present only in the adult phase and is independent of sex and/or familiarity with the release site. Moreover, adults released at a completely unfamiliar place oriented themselves in a direction roughly similar to that of their home pools. The fact that L. pholis were tested in a complete artificial environment means that hydrodynamic cues can be excluded as playing a role in this process and restricts the candidate options (e.g., magnetic cues). The ability to perform navigation based on a "map and compass" mechanism raises many interesting questions about the learning process, once these individuals have restricted home ranges during their lives. In vertebrate navigation, the cues used during the navigation process are a question of debate, and L. pholis offers an outstanding model to test hypotheses and ultimately provide answers.
Subject(s)
Fishes , Homing Behavior , Learning , Age Factors , Animals , Cues , Environment , Female , Male , Water MovementsABSTRACT
We report the development of new microsatellite markers that can be used for population analyses in the shanny Lipophrys pholis. The procedure involved the construction of a microsatellite-enriched genomic bank. Five (GT)(n) and (CT)(n) microsatellites have been characterized, four of which are polymorphic. The analysis of one population allowed us to verify their usefulness as markers in population studies. Moreover, interspecific amplifications have been performed using primers defined in other species to amplify Lipophrys pholis, or using the primers defined in Lipophrys pholis to amplify other species. We use these results to discuss the hypothesis that microsatellites are highly conserved in fish.
