Asentamiento diario de megalopas de jaibas del genero Cancer en un estuario micromareal

Pardo, Luis Miguel; Mora-Vásquez, Paulo; Garces-Vargas, José

doi:10.3856/vol40-issue1-fulltext-14

Cited by 7 publications

(8 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…edwardsii represents around 70% of national crab landings in artisanal fisheries [34]; exploitation is concentrated mainly around Chiloe Island in southern Chile [35]. The pelagic larval development of this species lasts three months (at 14±0.5°C) with five zoea larval stages and one megalopa stage [36] that settle mainly between November and December [37]. Adults inhabit subtidal environments, feeding on carrion and bivalves [38].…”

Section: Introductionmentioning

confidence: 99%

Highly Connected Populations and Temporal Stability in Allelic Frequencies of a Harvested Crab from the Southern Pacific Coast

et al. 2016

View full text Add to dashboard Cite

For marine invertebrates with a benthic adult form and a planktonic larva phase, the connectivity among populations is mainly based on larval dispersal. While an extended larval phase will promote gene flow, other factors such as an intensive fishery and geographical barriers could lead to changes in genetic variability. In this study, the population genetic structure of the commercial crab Metacarcinus edwardsii was analyzed along 700 km of the Chilean coast. The analysis, based on eight microsatellite loci genotyped from megalopae and adult crabs, considered temporal and spatial patterns of genetic variation. The results showed no evidence of spatial patterns in genetic structure, suggesting high connectivity among the sampling sites. The temporal analysis showed no evidence of changes in allele frequencies and no evidence of a recent bottleneck. The lack of spatial structure and allele variation over time could be explained by the interaction of factors such as i) low reproductive variance due to the capability of females to store sperm in the seminal receptacle, which can be used for successive broods, ii) high larval dispersal and iii) high individual reproductive output. Using our data as priors, a genetic modelling approach coincided, predicting this temporal and spatial stability. The same analysis showed that a reduction in population size leads to the loss of genetic variability in populations, as well as of the genetic cohesiveness between populations, pointing out the importance management for species under exploitation, such as M. edwardsii.

show abstract

Section: Introductionmentioning

confidence: 99%

Highly Connected Populations and Temporal Stability in Allelic Frequencies of a Harvested Crab from the Southern Pacific Coast

et al. 2016

View full text Add to dashboard Cite

show abstract

“…These months have the highest settlement rates for both species studied in the Valdivia estuary [36], [37]. Five trials (i.e.…”

Section: Methodsmentioning

confidence: 99%

“…In all cases a logarithmic transformation (ln × +1) was required. Daily settlement of M. edwardsii fluctuates, with many days with of low megalopae abundance [37], given that the goal in this study is test the cues for settlement, days with average settlement below 1 settler m − 2 day − 1 or with more than a 75% occurrence of 0 settlers in collectors were not included in the analysis (3 trials were excluded). When statistically significant differences were found in ANOVAs, Fisher-LSD post-hoc test were performed to determine homogeneous groups.…”

Section: Methodsmentioning

confidence: 99%

“…Previously, both species have been recorded recruiting in abundance in estuarine environments and larval supply to settlement habitats has been associated to tidal current and post-upwelling thermal fronts [36]–[37]. While the meso-scale pattern of settlement in estuaries is beginning to be understood, micro-scale processes remain largely unstudied.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Field Assessment of the Predation Risk - Food Availability Trade-Off in Crab Megalopae Settlement

Tapia‐Lewin

Pardo

2014

PLoS ONE

Self Cite

View full text Add to dashboard Cite

Settlement is a key process for meroplanktonic organisms as it determines distribution of adult populations. Starvation and predation are two of the main mortality causes during this period; therefore, settlement tends to be optimized in microhabitats with high food availability and low predator density. Furthermore, brachyuran megalopae actively select favorable habitats for settlement, via chemical, visual and/or tactile cues. The main objective in this study was to assess the settlement of Metacarcinus edwardsii and Cancer plebejus under different combinations of food availability levels and predator presence. We determined, in the field, which factor is of greater relative importance when choosing a suitable microhabitat for settling. Passive larval collectors were deployed, crossing different scenarios of food availability and predator presence. We also explore if megalopae actively choose predator-free substrates in response to visual and/or chemical cues. We tested the response to combined visual and chemical cues and to each individually. Data was tested using a two-way factorial design ANOVA. In both species, food did not cause significant effect on settlement success, but predator presence did, therefore there was not trade-off in this case and megalopae respond strongly to predation risk by active aversion. Larvae of M. edwardsii responded to chemical and visual cues simultaneously, but there was no response to either cue by itself. Statistically, C. plebejus did not exhibit a differential response to cues, but reacted with a strong similar tendency as M. edwardsii. We concluded that crab megalopae actively select predator-free microhabitat, independently of food availability, using chemical and visual cues combined. The findings in this study highlight the great relevance of predation on the settlement process and recruitment of marine invertebrates with complex life cycles.

show abstract

“…Considerando que el estuario del río Valdivia es considerado uno de los más importantes de Chile e incluso de Sudamérica (Perillo et al, 1999) y cumple roles ecosistémicos relevantes para especies comerciales (Vargas et al, 2003;Pardo et al, 2011Pardo et al, , 2012aPardo et al, , 2012b. Este estudio dilucida la hidrografía del estuario, necesaria para la implemen-tación de esfuerzos de conservación de hábitat vulnerables presentes en la zona (áreas de crianza de juveniles de especies explotadas) y la utilización de este sistema para actividades de acuicultura y manejo de recursos marinos.…”

Section: Introductionunclassified

Caracterizacion hidrografica del estuario del rio Valdivia, centro sur de Chile

Garces-Vargas¹,

Ruiz²,

Pardo³

et al. 2013

lajar

Self Cite

View full text Add to dashboard Cite

RESUMEN.La costa sureste del Océano Pacífico entre 37º y 41°S, se caracteriza por la presencia de un gran número de estuarios micromareales (rango mareal menor a 2 m). Uno de los estuarios más importantes dentro de estas latitudes es el estuario del río Valdivia, cuya estructura y dinámica termal y halina es poco conocida. Mediante mediciones hidrográficas de temperatura y salinidad tomadas durante un ciclo estacional anual y el análisis de sus principales forzantes (marea, caudal del río, vientos y radiación solar) se explica la variabilidad así como sus cambios en la estratificación vertical. El análisis de la estructura termohalina de la columna de agua reveló que el estuario varió estacionalmente comportándose como un estuario de cuña salina en invierno y primavera producto del mayor caudal de los ríos afluentes, mientras que en verano y otoño se comportó como parcialmente mezclado, producto del menor caudal de los ríos. En invierno y primavera la columna de agua presentó inversión térmica, la cual fue asociada a pérdida de calor superficial y a la advección subsuperficial de aguas cálidas desde el océano adyacente hacia el interior del estuario que no se mezclaron con las de la superficie debido a la intensa estratificación salina. El cambio en el régimen estuarino de cuña salina a parcialmente mezclado según la estación del año y presencia de la inversión térmica estacional, son características hidrográficas necesarias tanto para la implementación de esfuerzos de conservación de hábitat vulnerables presentes en la zona (áreas de crianza de juveniles de especies explotadas), como para la utilización de este sistema para actividades de acuicultura y manejo de recursos marinos. Palabras clave: hidrografía, boyantes, mezcla, inversión térmica, río Valdivia, Chile. Hydrographic features of Valdivia river estuary south-central ChileABSTRACT. The area between 37º and 41°S of the southeastern Pacific coast, have a great number of microtidal (tidal range less than 2 m) estuaries. One of the most important estuaries in these latitudes is the Valdivia River estuary, whose thermal and haline structure is poorly known. Thus, this work, through hydrographic measurements of temperature and salinity taken during an annual seasonal cycle and the analysis of the main forcings (tide, river flow, wind and solar radiation) explain the variability and its changes in vertical stratification. The analysis of the the thermohaline structure of the water column revealed that the estuary varied seasonally behaving like a salt-wedge estuary in winter and spring due to a higher flow of tributaries. However, in summer and autumn behaved as partially mixed due the lower river flow. In winter and spring the water column showed a temperature inversion which was associated with a large surface heat loss and subsurface advection of warm waters from the adjacent ocean to into the estuary that is not mixed with the surface due to intense stratification by salinity. The change in the estuarine salt-wedge regime to partially mixed according to t...

show abstract

Asentamiento diario de megalopas de jaibas del genero Cancer en un estuario micromareal

Cited by 7 publications

References 16 publications

Highly Connected Populations and Temporal Stability in Allelic Frequencies of a Harvested Crab from the Southern Pacific Coast

Highly Connected Populations and Temporal Stability in Allelic Frequencies of a Harvested Crab from the Southern Pacific Coast

Field Assessment of the Predation Risk - Food Availability Trade-Off in Crab Megalopae Settlement

Caracterizacion hidrografica del estuario del rio Valdivia, centro sur de Chile

Contact Info

Product

Resources

About