Migration timing of female kokanee salmon Oncorhynchus nerka: diel patterns and effects of maturation state

Abstract

Diel patterns of migration and migration speed were compared between reproductive timing phenotypes in female kokanee salmon Oncorhynchus nerka. Females of varying degrees of reproductive maturation were captured on their migration route to the Meadow Creek Spawning Channel (British Columbia, Canada), were tagged with passive-integrated transponders (PIT tags) and were subsequently monitored with stationary receivers. Females showed crepuscular migration timing, with approximately equal detections at dawn and dusk. In particular, peaks of movement were associated with the appearance of the sun over the mountains in the east and the disappearance of the sun over the mountains in the west. Over 25 m, migration speed was 1·0 body lengths (measured as fork length; L(F)) s(-1) and did not depend on maturation state. Over 3 km, migration speed was much slower (0·2-0·3 L(F) s(-1)) than over the short distance, with less mature females migrating more slowly than more mature females. Less mature females appeared to be in less of a hurry to reach breeding areas compared with more mature females.

Riverine characteristics and adult demography influence female lake sturgeon (Acipenser fulvescens) spawning behavior, reproductive success, and ovarian quality

“…Identifying factors influencing timing of reproduction, residency time on spawning grounds (RT), and reproductive success (RS) are essential for understanding the biological requirements and selective pressures acting on wild fish populations (Dickerson et al 2002;Seitz et al 2005;Wheeler et al 2016). Although timing of reproduction has a heritable basis (Neuheimer and MacKenzie 2014), individuals show behavioural plasticity in response to environmental cues, such as decisions about when and where to reproduce (Warren and Morbey 2012;Mittelbach et al 2014). For fishes that provide no parental care after spawning, exogenous conditions experienced while on the spawning grounds determine fertilization success as well as the abiotic conditions and predation pressure fertilized eggs and larvae will encounter (Lowerre-Barbieri et al 2016).…”

“…Female ovulation is largely driven by exogenous cues such as water temperature and social interactions within spawning sites (Webb et al 2001;Lowerre-Barbieri et al 2011;Morgan et al 2013). In contrast with teleost fishes where egg deposition occurs within days of ovarian maturation and ovulation (Bobe et al 2008;Warren and Morbey 2012), sturgeon can maintain postvitellogenic ovaries for months before spawning (Webb et al 1999). Prolonged periods between ovulation and egg deposition allow females the opportunity to be selective in their choice of mates and spawning locations (Brown- Peterson and Heins 2009).…”

Temporal spawning migration patterns of landlocked Atlantic salmon (Salmo salar) in a constructed stream

“…River discharge or changes in flow rates have often been considered important regulating factors controlling spawning migration for salmonids although this varies greatly by species and location (Banks 1969). Some of these external cues may include water temperature (Dahl et al 2004), diel period and lunar cycle (Forsythe et al 2012;Warren & Morbey 2012). In regulated rivers, particularly for landlocked salmonids, discharge cues are reduced (constant flow maintained) or kept at levels not normally experienced in nature and fish in these systems may rely on other environmental or internal cues to initiate spawning migration.…”

“…In regulated rivers, particularly for landlocked salmonids, discharge cues are reduced (constant flow maintained) or kept at levels not normally experienced in nature and fish in these systems may rely on other environmental or internal cues to initiate spawning migration. Some of these external cues may include water temperature (Dahl et al 2004), diel period and lunar cycle (Forsythe et al 2012;Warren & Morbey 2012).…”