Abstract
The Sense Acuity and Behavioral (SAAB) Hypothesis proposes that the swimming capabilities and sensorial acuity of temperate fish larvae allows them to find and swim towards coastal nursery areas, which are crucial for their recruitment. To gather further evidence to support this theory, it is necessary to understand how horizontal swimming capability varies along fish larvae ontogeny. Therefore, we studied the swimming capability of white seabream Diplodus sargus (Linnaeus, 1758) larvae along ontogeny, and their relationship with physiological condition. Thus, critical swimming speed (Ucrit) and the distance swam (km) during endurance tests were determined for fish larvae from 15 to 55 days post-hatching (DPH), and their physiological condition (RNA, DNA and protein contents) was assessed. The critical swimming speed of white seabream larvae increased along ontogeny from 1.1 cm s−1 (15 DPH) to 23 cm s−1 (50 and 55 DPH), and the distance swam by larvae in the endurance experiments increased from 0.01 km (15 DPH) to 86.5 km (45 DPH). This finding supports one of the premises of the SAAB hypothesis, which proposes that fish larvae can influence their transport and distribution in coastal areas due to their swimming capabilities. The relationship between larvae’s physiological condition and swimming capabilities were not evident in this study. Overall, this study provides critical information for understanding the link between population dynamics and connectivity with the management and conservation of fish stocks.
Highlights
The pelagic eggs and larvae of temperate marine fish species may remain in the pelagic environment for weeks or months before being recruited into nursery habitats [1,2]
The swimming performance of white seabream larvae was tested with 175 individuals, 143 for critical swimming speed (Ucrit ) and 32 for endurance trials
The larvae used in the endurance experiments came from a batch produced in May 2016, when the water temperature was higher, and for that reason, larvae were generally bigger at a given moment along ontogeny than the larvae tested in the critical swimming experiments (Figure 2)
Summary
The pelagic eggs and larvae of temperate marine fish species may remain in the pelagic environment for weeks or months before being recruited into nursery habitats [1,2]. Passive transport of eggs and pre-metamorphic larvae is dictated by currents, tides, and weather events [3], which may either transport them towards coastal nursery areas (i.e., coastal lagoons, estuaries, rocky shore habitats) or away from them [2]. This passive stage is greatly influenced by biological (e.g., starvation and predation) and physical processes related to larval transport and retention [4,5]. When post-flexion larvae are in the range of nursery cues, they orientate their swimming to follow odor, sound, and visual cues
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
