Breeding pattern and nest guarding in Sicyopterus lagocephalus, a widespread amphidromous Gobiidae

Otolith microchemistry can provide crucial information to address gaps of knowledge in spatio‐temporal ecology of fish species. However, understanding the seasonal variability of water chemistry and its effect on otolith signatures is needed to interpret fish movements. Otolith multi‐elemental signatures were used to examine the diadromous migration and small‐scale movements of a tropical goby (Sicyopterus lagocephalus) within a watershed in La Réunion Island, Indian Ocean. The elemental ratios Sr:Ca, Ba:Ca and Sr:Ba recorded monthly in the water of nine sampling sites varied between localities and were correlated with otolith signatures, whereas the Mg:Ca signature was not. The incorporation of some trace elements in otoliths was influenced by the size of fish and site where they were caught, reflecting an effect of endogenous and exogenous factors. Despite these sources of variation, the elemental signatures did not overlap for three river sections distributed along the 26‐km‐long watershed. The diadromous migration and fish lifetime movements between these river sections were reconstructed using an original process based on random forest analysis. This approach revealed distinct migratory behaviours after fish entered in the river, with some individuals progressing slowly in the watershed whereas other rapidly reached the upper localities. As adults, S. lagocephalus showed a restricted exploratory behaviour and a strong site fidelity to a particular part of the watershed. The detection of adult movement was typically only between adjacent locations and is possibly explained by shifts in local intraspecific hierarchies and/or displacement during extreme discharge caused by cyclones.

Section: Moreover the Steep Rivers With High Flow Velocity Of La Réumentioning

confidence: 91%

Site fidelity and movements of an amphidromous goby revealed by otolith multi‐elemental signatures along a tropical watershed

Teichert

Tabouret

Lagarde

et al. 2018

“…Reproduction occurs in rivers, continuously during the year, although it is more intense between January and June, thus coinciding with summer and autumn in the Southern Hemisphere (Delacroix & Champeau 1992;Hoareau et al 2007;Teichert et al 2013).…”

Section: Review On Biological Materialsmentioning

confidence: 99%

Morphological changes during the transition from freshwater to sea water in an amphidromous goby,Sicyopterus lagocephalus(Pallas 1770) (Teleostei)

Ellien

Werner

Keith

2014

The widely distributed amphidromous goby Sicyopterus lagocephalus needs drastic change of habitat to fulfil its life cycle: adults live and spawn in rivers, where eggs hatch into prolarvae that have to reach the sea to acquire characteristics of planktonic larvae. Postlarvae return to rivers where they recruit and grow to the adult reproductive stage. Here, we describe the prolarval stages, namely from hatching to first contact with sea water, as well as the first marine larval stages. The observations were made under experimental conditions. We described 3 prolarval substages in freshwater (L1a–L1c). Prolarvae present a slight but visible ontogenetic development in freshwater, during which the yolk sac begins to reduce, the pigmentation increases on the body and in the eyes, and the lenses appear, although the eyes are not functional. Prolarvae need to reach the sea in a maximum of 96 h to pursue their development. Their transfer in sea water at a salinity of 36.5 induces important morphological modifications (i.e. yolk sac full absorption, appearance of pectoral fins, migration of the eyes in anterolateral position of the head, opening of mouth and anus), enabling the organisms to adapt to their new environment. This marine stage is divided into two substages: L2a corresponding to the organisation of the morphological structures adapted to the marine environment and L2b during which these morphological structures become functional. Whether it is in freshwater or sea water, the duration of the substages depends on the water temperature, but is similar for all individuals for a given temperature.

“…The adults measure from 4 to 12 cm and are benthic herbivorous, feeding on micro-algae that cover rocks and pebbles (Bielsa et al 2003). Manacop 1953;Kinzie 1993), the females spawn a great number of eggs (15 000-230 000) on the underside of pebbles and boulders (Teichert et al 2013(Teichert et al , 2014. Manacop 1953;Kinzie 1993), the females spawn a great number of eggs (15 000-230 000) on the underside of pebbles and boulders (Teichert et al 2013(Teichert et al , 2014.…”

Section: Introductionmentioning

confidence: 99%

Pelagic larval traits of the amphidromous gobySicyopterus lagocephalusdisplay seasonal variations related to temperature in La Réunion Island

Teichert

Valade²,

Grondin³

et al. 2014

Amphidromous gobies represent a substantial part of freshwater fish diversity throughout islands of the Indo-Pacific region. They display a marine pelagic phase during several months before recruiting in rivers. Understanding the relationship between larval traits and environmental conditions is a major challenge for the evaluation of a spatial scale of connectivity and populations' dynamics, especially in a climate change context. In this study, the larval traits of Sicyopterus lagocephalus were examined and related to the sea surface temperature (SST), over three consecutive years in La R eunion Island (Mascarene archipelago). The pelagic larval duration (PLD, range from 96 to 293 days), the size-at-recruitment (range from 26.5 to 37 mm TL) and the larval growth rate (range from 0.112 to 0.293 mmÁday À1 TL) varied seasonally depending on hatching date. The larval growth rate was inversely correlated to the fluctuations of PLD and size. Larvae living in high sea water temperatures exhibited a faster growth, shorter PLDs and smaller sizes-at-recruitment than those living in cool water temperatures. The instantaneous daily growth was assessed by the study of otolith increment widths. The daily growth was not linear throughout larval life and was positively correlated to SST. We showed high amplitude of PLD periodic fluctuations (170.39 AE 43.75 days) related to temperature (12.8% PLD drop per degree), which could affect dispersal and induce intermittent connectivity between distant populations. This high plasticity of larval traits is likely to be advantageous to respond to the wide range of environmental conditions encountered throughout the species distribution range.