Trophic niche dynamics of three nearshore benthic predators in The Bahamas

Shipley, Oliver N.; Murchie, Karen J.; Frisk, Michael; O’Shea, Owen R.; Winchester, Maggie M.; Brooks, Edward J.; Pearson, Jessie M N; Power, Michael

doi:10.1007/s10750-018-3523-1

Cited by 28 publications

(23 citation statements)

References 50 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Bayesian-estimated SEA (SEA B ) was also calculated to validate maximum likelihood estimates. To provide a conservative estimate of niche overlap, we calculated overlap of the total trophic niche (an ellipse including 95% of the available data; see Shipley et al 2018) using Bayesian implemented methods in the R package nicheROVER (Swanson et al 2015). Overlap estimates were calculated from a run of 10 000 iterations.…”

Section: Methodsmentioning

confidence: 99%

Trophodynamics and mercury bioaccumulation in reef and open-ocean fishes from The Bahamas with a focus on two teleost predators

Shipley

Lee

Fisher

et al. 2019

Mar. Ecol. Prog. Ser.

View full text Add to dashboard Cite

Identifying prey resource pools supporting fish biomass can elucidate trophic pathways of pollutant bioaccumulation. We used multiple chemical tracers (carbon [δ13C] and nitrogen [δ15N] stable isotopes and total mercury [THg]) to identify trophic pathways and measure contaminant loading in upper trophic level fishes residing at a reef and open-ocean interface near Eleuthera in the Exuma Sound, The Bahamas. We focused predominantly on the trophic pathways of mercury bioaccumulation in dolphinfish Coryphaena hippurus and wahoo Acanthocybium solandri, 2 commonly consumed pelagic sportfish in the region. Despite residing within close proximity to productive and extensive coral reefs, both dolphinfish and wahoo relied almost exclusively on open-ocean prey over both short and long temporal durations. A larger isotopic niche of dolphinfish suggested a broader diet and some potential prey differentiation between the 2 species. THg concentrations in dolphinfish (0.2 ± 0.1 ppm) and wahoo (0.3 ± 0.3 ppm) were mostly below recommended guidelines for humans (US Environmental Protection Agency (EPA) = 0.3 ppm, US Food and Drug Administration (FDA)= 1.0 ppm) and were within ranges previously reported for these species. However, high THg concentrations were observed in muscle and liver tissue of commonly consumed reef-associated fishes, identifying a previously unrecognized route of potentially toxic Hg exposure for human consumers on Eleuthera and neighboring islands.

show abstract

Section: Methodsmentioning

confidence: 99%

Trophodynamics and mercury bioaccumulation in reef and open-ocean fishes from The Bahamas with a focus on two teleost predators

Shipley

Lee

Fisher

et al. 2019

Mar. Ecol. Prog. Ser.

View full text Add to dashboard Cite

show abstract

“…However, statistical power was low and the ability to detect relationships may have been limited due to small sample sizes and limited size ranges; size-based shifts in feeding might have been observed with greater replication. While more depth is needed in these data, it seems size-based effects on adult predator resource use are absent or weak here (Gallagher et al, 2017;Layman, Winemiller, Arrington, & Jepsen, 2005;Matley et al, 2017;Shipley et al, 2018). Within the diverse food webs of coral reefs where prey sizes vary, strong relationships with body size may be masked as predators target large primary consumers (Layman et al, 2005).…”

Section: Do the Isotopic Niches Of Sympatric Predators Overlap?mentioning

confidence: 99%

“…Studies of vertebrate marine predator trophic niches and dietary specializations have focussed on elasmobranchs (Gallagher et al, 2017;Matich et al, 2011;Shiffman, Kaufman, Heithaus, & Hammerschlag, 2019;Shipley et al, 2018) and birds (Bodey et al, 2018;Patrick et al, 2014), with most studies focussing on only a few co-occurring species. There is a lack of isotopic information on resource partitioning among co-occurring teleost predators (Matley, Tobin, Simpfendorfer, Fisk, & Heupel, 2017), particularly in the tropics (Cameron et al, 2019).…”

mentioning

confidence: 99%

Novel tri‐isotope ellipsoid approach reveals dietary variation in sympatric predators

Skinner

Mill

Newman

et al. 2019

Ecology and Evolution

View full text Add to dashboard Cite

Sympatric species may partition resources to reduce competition and facilitate co‐existence. While spatial variation and specialization in feeding strategies may be prevalent among large marine predators, studies have focussed on sharks, birds, and marine mammals. We consider for the first time the isotopic niche partitioning of co‐occurring, teleost reef predators spanning multiple families. Using a novel tri‐isotope ellipsoid approach, we investigate the feeding strategies of seven of these species across an atoll seascape in the Maldives. We demonstrate substantial spatial variation in resource use of all predator populations. Furthermore, within each area, there was evidence of intraspecific variation in feeding behaviors that could not wholly be attributed to individual body size. Assessing species at the population level will mask these intraspecific differences in resource use. Knowledge of resource use is important for predicting how species will respond to environmental change and spatial variation should be considered when investigating trophic diversity.

show abstract

“…Therefore, we used the total trophic niche (i.e. ellipses incorporating 95% of data) to calculate relative niche overlap to balance type I and type II errors and account for individual variability across the sampled population (Shipley et al 2018a).…”

Section: Discussionmentioning

confidence: 99%

Questioning assumptions of trophic behavior in a broadly ranging marine predator guild

et al. 2019

Self Cite

View full text Add to dashboard Cite

We evaluated whether existing assumptions regarding the trophic ecology of a poorly‐studied predator guild, northwest (NW) Atlantic skates (family: Rajidae), were supported across broad geographic scales. Four hypotheses were tested using carbon (δ13C) and nitrogen (δ15N) stable isotope values as a proxy for foraging behavior: 1) species exhibit ontogenetic shifts in habitat and thus display a shift in 13C with differential use of the continental shelf; 2) species exhibit ontogenetic prey shifts (i.e. from smaller to larger prey items) and become enriched in 15N; 3) individuals acquire energy from spatially confined local resource pools and exhibit limited displacement; and 4) species exhibit similarly sized and highly overlapping trophic niches. We found some evidence for ontogenetic shifts in habitat‐use (δ13C) for thorny and little skate and diet (δ15N) of thorny and winter skate and hypothesize that individuals exhibit gradual trophic niche transition, especially in δ15N space, rather than a clear and distinct shift in diet throughout ontogeny. Spatial isoscapes generated for little, thorny, and winter skate highlighted distinct spatial patterns in isotopic composition across the coastal shelf. For little and thorny skate, patterns mimicked expected spatial variability in the isotopic composition of phytoplankton/POM, suggesting limited displacement and utilization of spatially confined resource pools. Winter skate, however, exhibited a much narrower range of δ13C and δ15N values, suggesting individuals may use resources from a more confined latitudinal range. Although high total trophic niche overlap was observed between some species (e.g. little and thorny skate), sympatric species (e.g. little and winter skate) exhibited a degree of trophic niche separation. These findings offer new insight into the trophic dynamics of a poorly‐studied, vulnerable group of predators, and highlight a need to re‐examine assumptions pertaining to aspects of their ecology.

show abstract

Trophic niche dynamics of three nearshore benthic predators in The Bahamas

Cited by 28 publications

References 50 publications

Trophodynamics and mercury bioaccumulation in reef and open-ocean fishes from The Bahamas with a focus on two teleost predators

Trophodynamics and mercury bioaccumulation in reef and open-ocean fishes from The Bahamas with a focus on two teleost predators

Novel tri‐isotope ellipsoid approach reveals dietary variation in sympatric predators

Questioning assumptions of trophic behavior in a broadly ranging marine predator guild

Contact Info

Product

Resources

About