scholarly journals Spatial and temporal variation in the natal otolith chemistry of a Hawaiian reef fish: prospects for measuring population connectivity

2008 ◽  
Vol 65 (6) ◽  
pp. 1181-1192 ◽  
Author(s):  
Benjamin I. Ruttenberg ◽  
Scott L. Hamilton ◽  
Robert R. Warner

One of the most compelling unanswered questions in marine ecology is the extent to which local populations are connected via larval exchange. Recent work has suggested that variation in the chemistry of otoliths (earstones) of fishes may function as a natural tag, potentially allowing investigators to determine sources of individual larvae and estimate larval connectivity. We analyzed the spatial and temporal variation in natal otolith chemistry of a benthic-spawning reef fish from the Hawaiian Islands. We found no consistent chemical variation at the largest scale (>100 km, among islands), but found significant variation at moderate scales (sites within islands, tens of kilometres) and small scales (clutches within sites), and chemistry of otoliths was not stable between years. These results imply that we may be able to use otolith chemistry to track larval dispersal only if the scales of dispersal match those of variation in natal otolith chemistry, and that separate natal otolith collections may be needed to track different cohorts of larvae. Finally, we found that elemental composition of recruit cores often did not match that of natal otoliths, suggesting that additional methodological development is required before we can effectively apply methods in otolith chemistry to the study of larval dispersal.

2011 ◽  
Vol 279 (1735) ◽  
pp. 1883-1888 ◽  
Author(s):  
Peter M. Buston ◽  
Geoffrey P. Jones ◽  
Serge Planes ◽  
Simon R. Thorrold

A central question of marine ecology is, how far do larvae disperse? Coupled biophysical models predict that the probability of successful dispersal declines as a function of distance between populations. Estimates of genetic isolation-by-distance and self-recruitment provide indirect support for this prediction. Here, we conduct the first direct test of this prediction, using data from the well-studied system of clown anemonefish ( Amphiprion percula ) at Kimbe Island, in Papua New Guinea. Amphiprion percula live in small breeding groups that inhabit sea anemones. These groups can be thought of as populations within a metapopulation. We use the x- and y -coordinates of each anemone to determine the expected distribution of dispersal distances (the distribution of distances between each and every population in the metapopulation). We use parentage analyses to trace recruits back to parents and determine the observed distribution of dispersal distances. Then, we employ a logistic model to (i) compare the observed and expected dispersal distance distributions and (ii) determine the relationship between the probability of successful dispersal and the distance between populations. The observed and expected dispersal distance distributions are significantly different ( p < 0.0001). Remarkably, the probability of successful dispersal between populations decreases fivefold over 1 km. This study provides a framework for quantitative investigations of larval dispersal that can be applied to other species. Further, the approach facilitates testing biological and physical hypotheses for the factors influencing larval dispersal in unison, which will advance our understanding of marine population connectivity.


2010 ◽  
Vol 22 (3) ◽  
pp. 177-187 ◽  
Author(s):  
Elaine Bernini ◽  
Maria A. B. da Silva ◽  
Tania M. S. do Carmo ◽  
Geraldo R. F. Cuzzuol

Spatial and temporal variation of the nutrient concentrations in leaves and sediment between the roots of Laguncularia racemosa (L.) Gaertn. f and Rhizophora mangle L. was analyzed in the mangrove forest of the estuary of São Mateus River, Espírito Santo, Brazil. In leaves, the nutrients followed the sequence: N> Ca> K> Mg> S> P> Fe> Mn> Zn> Cu, and there were significant differences between species and sites studied. In general, the levels of K were higher in the dry season compared to the rainy season for both species analyzed while Ca and Cu showed higher concentrations in the rainy season for Laguncularia racemosa. In the sediment, the nutrients followed the sequence: Mg> Ca> Fe> K> Mn> P> Zn> Cu, in general, with lower concentrations at the site where the sediment was sandier. We observed a significant variation of nutrient concentrations in the sediment between the periods analyzed, but the seasonal pattern was not clear for all nutrients. Nutrient concentration profile found in leaves of both plant species was not correlated with concentrations found in the respective sediments. The concentration factor was less than 1.0 for Fe and between 1.0 and 3.7 for Mn, Zn and Cu. These results provide physiological evidences about the relevance of these tree species for the role of mangroves as biogeochemical barriers to the transit of heavy metals.


2002 ◽  
Vol 59 (4) ◽  
pp. 669-679 ◽  
Author(s):  
Bronwyn M Gillanders

Interannual variability in elemental composition of otoliths may confound spatial interpretations. The elemental fingerprints of otoliths of juvenile fish were determined for fish collected from 12 to 15 estuaries in each of three consecutive recruitment years to determine temporal variation in otolith chemistry for each estuary. It was also examined whether there is overlap in elemental fingerprints of fish collected in different years and from different estuaries that may confound subsequent spatial comparisons. Significant differences in otolith chemistry were found among years for individual elements (lithium, manganese, strontium, and barium) and for multi-element fingerprints. Some estuaries showed large variation in multi-element fingerprints among years, whereas others showed little variation among years. There was some overlap of elemental fingerprints of different estuaries, but these were not always for fish collected in the same year. The significant spatial and temporal variation in elemental fingerprints meant that it was possible to confound spatial differences with temporal differences. Therefore, if the natal estuary of the adults is to be determined, a library of elemental fingerprints needs to be built up over time for each estuary rather than a single year-class of juveniles being used as the elemental fingerprint for a number of year-classes of adults.


2012 ◽  
Vol 19 (2) ◽  
pp. 201-216 ◽  
Author(s):  
Ivan Mateo ◽  
Edward G. Durbin ◽  
David A. Bengtson ◽  
Richard Kingsley ◽  
Peter K. Swart ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document