Growth of the Humboldt Current krill in the upwelling zone off central Chile

Riquelme‐Bugueño, Ramiro; Silva-Aburto, Jocelyn; Escribano, Rubén; Peterson, William T.; Schneider, Wolfgang

doi:10.1016/j.jmarsys.2016.06.001

Cited by 10 publications

(8 citation statements)

References 51 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…; Riquelme‐Bugueño et al. , , , ,b), the reproductive biology of this species has not received sufficient attention. This study is the first to collect gravid females of E. mucronata and provides an opportunity to record embryonic and early larval stages of this species.…”

Section: Discussionmentioning

confidence: 99%

“…Although the biology and ecology of Euphausia mucronata in the HCS have been studied intensively in recent years (Manr ıquez et al 2012;Riquelme-Bugueño et al 2012, 2013, 2016a, the reproductive biology of this species has not received sufficient attention. This study is the first to collect gravid females of E. mucronata and provides an opportunity to record embryonic and early larval stages of this species.…”

Section: Discussionmentioning

confidence: 99%

“…), and growth rates (Riquelme‐Bugueño et al. ,b). Although E. mucronata is considered an ecologically relevant species in the HCS, the species’ biology is relatively unknown, particularly the reproductive strategies, embryonic and larval ontogeny, and larval recruitment.…”

mentioning

confidence: 99%

See 2 more Smart Citations

Embryo and early larval stages of the Humboldt Current krill Euphausia mucronata (Crustacea: Euphausiacea)

Riquelme‐Bugueño

Gómez‐Gutiérrez

Silva-Aburto

et al. 2017

Invertebrate Biology

Self Cite

View full text Add to dashboard Cite

The Humboldt Current krill, Euphausia mucronata (Crustacea: Euphausiacea), is an endemic and keystone species in the food web of this highly productive eastern border current ecosystem. The morphology and ontogeny of E. mucronata is known from calyptopis I to the adult phase, but the embryonic and early‐life stages (nauplius and metanauplius) of this broadcast spawning species are unknown. We describe the morphology and development time of these life stages to complete the knowledge of its life cycle. Embryos were obtained from purple‐gonad gravid females collected off Dichato, central Chile, during November 2012. Eight gravid females (mean=16 mm total length) were incubated in seawater at 12°C under laboratory conditions. The average development time from single‐cell embryos to the metanauplius stage was 2.2 d and hatching occurred between 20 and 25 h. The average growth rate was 0.35 mm d−1 from the late limb bud to the metanauplius stage (range=0.21–0.48 mm d−1). Embryos of E. mucronata had a mean chorion diameter of 0.460 mm, embryo diameter of 0.343 mm, and perivitelline space of 0.056 mm. Our biological information reported here constitutes a baseline for future ecological studies on distribution and temporal variability of spawning activity and reproductive strategies of E. mucronata in the highly variable and productive Humboldt Current ecosystem.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Embryo and early larval stages of the Humboldt Current krill Euphausia mucronata (Crustacea: Euphausiacea)

Riquelme‐Bugueño

Gómez‐Gutiérrez

Silva-Aburto

et al. 2017

Invertebrate Biology

Self Cite

View full text Add to dashboard Cite

show abstract

“…Gonzaĺez et al (2021) found no relationship between chlorophyll-a concentration and Humboldt krill developmental stages. However, to properly determine whether there is food limitation, it is necessary to incorporate food ingestion rates (Antezana, 2010), growth rates (Riquelme-Bugueño et al, 2016), and biomass production (Riquelme-Bugueño et al, 2013) in future studies, to observe changes in these population parameters under different productivity scenarios.…”

Section: Impacts Of Thermal Fluctuations Food Availability Advection ...mentioning

confidence: 99%

Disentangling species-specific krill responses to local oceanography and predator’s biomass: The case of the Humboldt krill and the Peruvian anchovy

et al. 2022

View full text Add to dashboard Cite

Euphausiids (hereafter “krill”) are one of the main components of the pelagic communities of the Humboldt Current System (HCS). Their community dynamics have been well studied in central-southern Chile where upwelling is strongly seasonal, but little is known about the permanent-upwelling area of the HCS, which yields the largest fishery in the world, the Peruvian anchovy. We applied hierarchical generalized additive models with environmental and biological predictors to determine the main drivers of krill abundance, adjusting species-specific functions. We used a time series of 16 bi-annual surveys to study annual, seasonal, and spatial scales of variability of the four numerically dominant taxa: Euphausia mucronata (Humboldt krill), E. eximia, Stylocheiron affine, and Nematoscelis spp. The spatial pattern of the Humboldt krill (the dominant species) proved it is an upwelling-associated species, with higher abundances within 10 km from the coast. The other 3 taxa showed opposite spatial patterns with higher abundances offshore. The main covariates explaining krill abundances were the depth of the upper limit of the oxygen minimum zone (dOMZ) and the mean temperature of the water column. Humboldt krill was negatively correlated to both drivers, and the opposite effect was observed for the other taxa. Although many krill species are metabolically adapted to cope with the severe hypoxic conditions of this system, the Humboldt krill was the only species with higher modeled abundances when dOMZ was shallower. Chlorophyll-a remained high during all sampling periods, and it was an insignificant predictor for all taxa, suggesting food is not a limitation for krill in this highly productive system. The acoustic biomass of the Peruvian anchovy had a negative non-linear effect on the abundances of the Humboldt krill, and higher Humboldt krill abundances were found in areas with no anchovy hotspots. Our results indicate that krill in this system are susceptible to changes in temperature, oxygen, and upwelling conditions. Extreme events (e.g. heatwaves and ENSO events) are expected to increase in frequency and intensity, while climate change scenarios show a potential intensification of upwelling. These conditions could lead to distribution displacements and alter trophic interactions by modifying the distribution and biomass of the predator.

show abstract

“…This phenomenon has usually been interpreted as a response of krill to suboptimal environmental conditions (temperature, food) and/ or as an alternative source of energy for gonad development (reproduction) and growth during periods of scarce food (as an overwintering strategy) (Ikeda & Dixon 1982, Quetin & Ross 1991. However, experimental evidence suggests that shrinking in krill occur throughout the year round in polar (Nicol 2000, Tarling et al 2006, temperate (Pinchuck & Hopcroft 2007, Feinberg et al 2007, Shaw et al 2010, Pond et al 2012, Riquelme-Bugueño et al 2016, and subtropical krill species (Gómez-Gutiérrez et al 2012). These studies, among others, provide evidence that: 1) growth in krill is not necessarily limited by food but in occasions caused by anomalous changes in temperatures (Marinovic & Mangel 1999), 2) growth is highly variable at intraspecific and interspecific levels and body growth rates in females is negative correlated with brood size and interbrood periods (Feinberg et al 2007), and 3) positive, zero and negative growth should occur in any krill species because this physiological process have been observed in species from distinct biogeographic affinities (Atkinson et al 2006, Tarling et al 2006, Shaw et al 2010, Gómez-Gutiérrez et al 2012, Pond et al 2012.…”

Section: Introductionmentioning

confidence: 99%

First measurements of euphausiid growth rates in the northern Humboldt Current (23ºS)

Riquelme‐Bugueño¹,

Gómez‐Gutiérrez²,

Escribano³

et al. 2016

Rev. biol. mar. oceanogr.

Self Cite

View full text Add to dashboard Cite

Abstract.-One hundred and five juveniles and adults of Euphausia mucronata were incubated in order to estimate their daily growth rates (DGR) using the standard instantaneous growth rate method. . DGRs were positive (31%), zero (12%) and negative (57%). DGR<0 evidenced body shrinking process suggesting that environmental conditions in austral autumn 2010 were unfavorable for the krill population. However, because females had DGR<0 values more frequently than males it is probable that females also used part of their energy on gonad development rather than body growth.

show abstract

Growth of the Humboldt Current krill in the upwelling zone off central Chile

Cited by 10 publications

References 51 publications

Embryo and early larval stages of the Humboldt Current krill Euphausia mucronata (Crustacea: Euphausiacea)

Embryo and early larval stages of the Humboldt Current krill Euphausia mucronata (Crustacea: Euphausiacea)

Disentangling species-specific krill responses to local oceanography and predator’s biomass: The case of the Humboldt krill and the Peruvian anchovy

First measurements of euphausiid growth rates in the northern Humboldt Current (23ºS)

Contact Info

Product

Resources

About