12 research outputs found
Homing in rocky intertidal fish. Are Lipophrys pholis L. able to perform true navigation?
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
Molecular data confirm the validity of the portuguese blenny (Parablennius ruber, Valenciennes, 1836) and its presence in Western Europe
DNA sequence analysis confirms the distinction between Parablennius ruber and Parablennius
gattorugine, simultaneously validating the presence of the former species in Western Europe
where it has been reported for >150 years. A possible scenario involving speciation of P. ruber at
the Azores and subsequent transport of larvae to Europe, a process that may be still occurring
nowadays, could explain this pattern of occurrence
Phylogeny of the shanny, Lipophrys pholis, from the NE Atlantic using mitochondrial DNA markers
Inexistent
Citizen science and expert judgement: A cost-efficient combination to monitor and assess the invasiveness of non-indigenous fish escapees
Mapping the distribution and evaluating the impacts of marine non-indigenous species (NIS) are two fundamental tasks for management purposes, yet they are often time consuming and expensive. This case study focuses on the NIS gilthead seabream Sparus aurata escaped from offshore farms in Madeira Island in order to test an innovative, cost-efficient combined approach to risk assessment and georeferenced dispersal data collection. Species invasiveness was screened using the Aquatic Species Invasiveness Screening Kit (AS-ISK), and revealed a high invasion risk. Occurrences of S. aurata were assessed involving citizens in GIS participatory mapping and data from recreational fishing contests. A probability map showed that S. aurata is well dispersed around Madeira Island. This assessment proved to be a cost-efficient early warning method for detecting NIS dispersal, highlighting the urgent need for additional surveys that should search for sexually mature individuals and assess the direct and indirect impacts in the native ecosystemFundação para a Ciência e Tecnologia - FCTinfo:eu-repo/semantics/publishedVersio
Breves considerações sobre a eco-etologia de Lypophrys trigloides (Pisces : Blenniidae)
Dissertação de Mestrado em Etologi
Molecular validation of the specific status of Parablennius sanguinolentus and Parablennius parvicornis (Pisces: Blenniidae)
Parablennius sanguinolentus and P. parvicornis have been classified as either two distinct species or as two sub-species depending on the different criteria used to classify them. An analysis of fragments of mitochondrial 12S and 16S rDNA showed that the genetic distance between samples of P. sanguinolentus and P. parvicornis is similar or higher than those found for other blenniids that are widely recognized as distinct species. These results, together with the distinct geographical distributions and meristic differences, support the conclusion that P. sanguinolentus and P. parvicornis should be considered as two different species
Agonistic behaviour and sound production in Gaidropsarus mediterraneus, (Gadidae)
Agonistic behaviour and sound production were described for captive Gaidropsarus mediterraneus, a shore-dwelling gadoid. Thump-like sounds were produced during agonistic interactions, which involved disputes over access to shelter sites
Home sweet home: evidence for nest-fidelity in the rocky intertidal fish, the shanny Lipophrys pholis
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.Fundação para a Ciência e a Tecnologia (FCT
On the absence of genetic differentiation between morphotypes of the ballan wrasse Labrus bergylta (Labridae)
The ballan wrasse, Labrus bergylta (Labridae),
is a protogynous hermaphrodite fish common in the
north-eastern Atlantic from Norway to Morocco. It is a
commercially important resource for local fisheries and is
currently being used as cleaner fish to control sea lice in
salmon farms in northern Europe. Two distinct colour patterns
have been recently reported in the literature: plain and
spotted. These individuals follow strikingly different life
history strategies raising the question of whether they represent
one or two independent taxonomic units. Analyses
of mitochondrial (18S, COI and control region) and nuclear
(S7) markers revealed no genetic differences between these
morphotypes. Alternative explanations for the origin and
persistence of distinct morphotypes are discussed.Fundação para a Ciência e a Tecnologia (FCT); European Commissio