Realm: Marine
Climate: Temperate/Tropical
Biome: Temperate shelf and seas ecoregions
Central latitude: -28.493581
Central longitude: -71.860312
Duration: 8 years, from 2002 to 2009

1313 records

106 distinct species

Across the time series Paracalanus indicus is the most frequently occurring species

Methods

2.1. The study areaThe coastal upwelling zone of Chile (Fig. 1) extends from 18?Sto about 42?S. i.e. nearly 2700 km of coast along the latitudinalgradient. Because of different seasonal regimes of the upwellingprocess. two major upwelling regions can be distinguished.(1)The northern upwelling region(18??30? S). and (2) the Central/southern upwelling region (30??42?S). Both regions are known torepresent key coastal upwelling systems supporting high primaryproduction rates (Daneri et al..2000). strong fishery activitymostly based on small pelagic fishes(Alheit and Bernal.1993;Arcos et al..2001) and are subjected to strong interannualvariability forced by the ENSO (El Nino southern oscillation) cycle(Escribano et al..2004).2.2. Data sourcesLocations of all sampling sites are illustrated in Fig. 1. For thisstudy. we used samples from northern Chile obtained during theyears 2005. 2006 and 2007. The first set of samples comes fromthe ZOMEI Cruise carried out between September and October2005 at two locations off 20?S and 22?S. We used the samplesfrom a single station at each site sampled day and night in 5 depthstrata down to 700m. All these samples were obtained withvertical tows of a Hydrobios Midi-type multinet (0.25m2 openingmouth) equipped with five 200 mm mesh-size nets. A second setof samples came from the CENSOR (Climate Variability and the ElNino Southern Oscillation) project through which two fixednear shore stations located off Chipana at 21?S (90 m depth) andMejillones 23?S (85 m depth) were sampled during severalconsecutive days (5?8 days) in the summers and winters 2005.2006 and 2007. In both sites. the samples were obtained in twodepth strata with vertical tows of a 0.196m2 opening mouth WPnet having a 200 mm mesh-size net.In the Central/southern region samples came from twosources. Firstly the COPAS Time Series Study off Concepcion(Escribano and Schneider. 2007). In this study. zooplanktonsamples were obtained monthly at the fixed Station 18 using a200 mm mesh-size 1m2 Tucker Trawl net to wedobliquely at twodepth strata(0?50 m and 50?80m). Details on samplin gearprovided in Escribano et al.(2007). For this work.we used onlythe samples obtained during 2002 and 2003. which have beenanalyzed in detail for copepod composition. Monthly changes ofdominant copepod species (10% of total species) were previouslyassessed for the period 2002?2005 (Escribano et al..2007). and forthe period 2002?2008 the same dominant species were used toestimate interannual changes in copepod biomass (Escribanoet al.. submitted for publication). A second set of samples for thissouthern region came from the BIOZOO cruise carried outin winter 2008 at 5 stations over a cross-shelf transect from 5 to100 km offshore. At each station the same Hydrobios Multinet asabove was deployed to sample 4 strata down to 600 m at theoffshore station. In this case oblique tows were performed tosample a greater volume of water (410 m3) because of lowercopepod density in winter conditions.A total number of 159 samples were analyzed for this study.107 samples were from the Northern region and 52 from theCentral/Southern zone. From these samples. all copepods wereidentified to the species level(adults and copepodids. but notnauplii) and counted. although some very dense samples weresplit with a Folsom splitter to count a maximum number of 200individuals of a single dominant species. Unit of abundance = IndCountInt, Unit of biomass = NA

Citation(s)

Escribano, R., Manríquez, K. & Godoy, F. (2006) "Copepoda-COPAS Center (COPAS_CPD1) - Planktonic copepods from the Chilean Humboldt Current System - Eastern South Pacific Regional Node of OBIS (ESPOBIS)". Available at: http://www.iobis.org, accessed 2012.
Hidalgo, P., Escribano, R., Vergara, O., Jorquera, E., Donoso, K. & Mendoza, P. (2010) Patterns of copepod diversity in the Chilean coastal upwelling system. Deep Sea Research Part II: Topical Studies in Oceanography, 57, 2089–2097.