Does Daily Growth Affect the Rate of Manganese Uptake in Juvenile River Herring Otoliths?

Abstract

Manganese is a commonly found constituent in fish otoliths, yet a direct correlation with ambient water concentrations as observed for other elements has proven elusive. There is compelling evidence that Mn uptake is related to the availability of reduced Mn (Mn2+) resulting from hypoxia (Limburg et al. 2015) but that fish growth rate also plays a role. We tested the latter possibility by examining otoliths from anadromous river herring (Alewife Alosa pseudoharengus and Blueback Herring A. aestivalis) in New York waters. A significant correlation was found between the ages at which shifts in otolith daily growth increments (assumed proportional to somatic growth) and shifts in otolith Mn:Ca ratios were detected. Furthermore, significant positive Spearman's rank correlations were observed between mean otolith daily growth and otolith Mn:Ca. Species‐ and site‐specific differences were evident, but significant positive correlations were found for these relationships within each species and at most sampling sites. Ambient water concentrations were weakly correlated with otolith Mn:Ca, suggesting that both exogenous and endogenous factors influence Mn:Ca in otoliths. Thus, while endogenous mechanisms (i.e., growth rate) likely influence Mn uptake, exogenous availability is the ultimate control.

Otolith chemistry does not just reflect environmental conditions: A meta‐analytic evaluation

“…These experiments should be extended to consider changes to ion–protein interactions, given that these are likely the common mechanism via which physiological processes modify element availability and incorporation into the otolith (Sturrock et al., ), namely to evaluate how plasma protein concentrations determine ion availability in the endolymph and subsequent otolith chemistry (Grønkjær, ; Thomas et al., ). There is also growing evidence of the role of a suite of intrinsic factors influential on otolith elemental incorporation (e.g., growth rate, ontogeny, maturation/reproduction, condition, sex or genetics and population specific responses to name but a few: Chang & Geffen, ; Clarke et al., ; Izzo et al., ; Secor & Rooker, ; Stanley et al., ; Sturrock et al., ; Turner & Limburg, ), and this requires further investigation. In particular, as growth and reproduction have been shown to wield a major influence in element incorporation (e.g., Stanley et al., ; Sturrock et al., ), the general focus of validation experiments on juvenile fish implies that caution should also be used when interpreting patterns observed in mature/adult fish given the potential for differences in physiology and metabolism between life history stages (e.g., Darnaude et al., ; Sturrock et al., ).…”

“…However, we were not exhaustive in including all potential factors that may influence element incorporation, as data for these factors are limiting. Rates of aragonite precipitation and otolith growth influence the incorporation of elements into otoliths (Grønkjær, ; Sturrock et al., ; Turner & Limburg, ), which may be particularly influential for elements that substitute for Ca, such as Sr and Ba (Doubleday et al., ; Thomas et al., ). Ultimately, regulation of environmental Ca and its competing Ca 2+ mimics governs what is incorporated in the aragonite matrix and defines the uptake kinetics of Sr and Ba (Loewen et al., ; Thomas et al., ).…”

Otolith Microchemistry of Common Carp Reflects Capture Location and Differentiates Nurseries in an Interconnected Lake System of the North American Midwest

“…The relationship is likely confounded by other intrinsic and extrinsic factors that influence incorporation of trace elements into fish otoliths and by the mobility of Common Carp in this system. Ontogeny (Brophy et al 2004), diet (Buckel et al 2004), temperature (Collingsworth et al 2010), and fish growth rates (Turner and Limburg 2015) can all affect the rate at which trace elements are incorporated into fish otoliths although environmental conditions appear to contribute differentially to elemental incorporation within the otolith (Izzo et al 2018). Mobility of Common Carp in the study area likely also had further confounding effects on elemental incorporation reflecting environmental conditions.…”

“…A recent meta‐analysis of otolith microchemistry confirms that incorporation of trace elements into the calcium carbonate (CaCO 3 ) matrix of the otolith is differentially affected by environmental conditions in comparison to the influence of extrinsic and intrinsic factors (Izzo et al 2018). Factors that have been shown to affect the rates at which these elements become incorporated into otoliths include ontogeny (Brophy et al 2004; Hegg et al 2019), diet (Buckel et al 2004), temperature (Collingsworth et al 2010), and fish growth rates (Turner and Limburg 2015). The effect of intrinsic factors on the incorporation of elements into the otolith presents a significant challenge when interpreting environmental histories of fish.…”

Fine‐scale variability in elemental composition of estuarine water and otoliths: Developing environmental markers for determining larval fish dispersal histories within estuaries

“…In this study, Mn : Ca water was also an important factor in discriminating between the halocline and marine layers and was correspondingly related to Mn : Ca otolith . Manganese (Mn) varies greatly in estuaries and this is likely due to microbial activity and linked to hypoxia/anoxia (Mohan et al ; Ramsay et al ; Turner and Limburg ). It is these characteristics that make Mn an element of interest for distinguishing between water layers as the bottom marine layers tend to be hypoxic, even anoxic, in stratified estuaries, while the halocline and upper layers are either well mixed or are an area of high productivity.…”