Dataset: Total biovolume of zooplankton collected in upper 50 meters of water column using Hensen nets from R/V Jose Olaya cruises in the Humboldt Current Peruvian coast, 4-18 S, 72-80 W (PCE project)

Zooplankton were collected using Hensen nets in top 50 meters of the water column from Humboldt Current Ecosystem - Peruvian coast 4-18 degrees South latitude, 72-80 degrees West longitude. Some brief cruise information is available as a PDF file.

Note about data availability:
The sharing of data with other colleagues is subject to an inter-institutional agreement with IMARPE, with some restrictions applying to the use of data by people not directly involved in the agreement, and restrictions for the use of the data after the end of the agreement.

Investigators interested in gaining access to the original data are encouraged to contact:
Patricia Ayòn
IMARPE (Instituto del Mar del Perú)
payon [AT] imarpe [DOT] gob [DOT] pe

Examples from Original Data Files

Original data files exist in Excel spreadsheet files. These include stations (Est), longitude and latitude, date (FECHA), time (HORA), surface temperature (TSM), zooplankton biovolume (Volumen) and numbers of anchovy eggs (Huevos anch) and larvae (Larvas anch).

Example original data
Station	Longitude	Latitude	DATE	TIME	Surface Temp	Volume	Eggs	Larvae
E-1/C-1JOB	-70.715	-18.2	11/2/2003	23:57	19.8	8	411	6
E-11/C-2	-71.176	-17.907	11/3/2003	11:33	19.26	2	3	39
14	-71.363	-17.724	11/3/2003	14:15	19.15	1.5	0	0

 

Additional processing of these data combined all usable surveys into a single flat (text) file additionally calculated distance to the coast (dc) and to the 200-m isobath (dist200) and added surface temperature (SST) and salinity (SSS) where available. Distances are in km.

 

Example processed data
year	mo	time	lat	dc	dist200	vol	SST	SSS
1990	12	1.083333333	-18.38333333	176.192184	150.9670611	4	21.9	34.978
1990	12	4.083333333	-18.05	107.3411666	87.1060464	18	21.4	34.824
1990	12	6.733333333	-17.7	20.5228905	19.1680014	5	21.2	34.872
1990	12	21.35	-17.48333333	3.84008226	-15.799166	10	16.2	34.734

 

References

 

Ayón P, and G. Swartzman. (2008) Changes in the long-term distribution of zooplankton in the Humboldt Current Ecosystem off Peru, and its relationship to regime shifts and environmental factors. Fisheries Oceanography, Vol. 17, No. 6. pp. 421-431.

Ayón P, Criales-Hernandez MI, Schwamborn R, Hirche HJ (2008) Zooplankton research off Peru: A review. Prog Oceanogr 79:238-255
(this paper contains references to internal reports describing the data for many of the surveys)

Ayón P, Swartzman G, Bertrand A, Gutiérrez M, Bertrand S (2008) Zooplankton and forage fish species off Peru: Large-scale bottom-up forcing and local-scale depletion. Prog Oceanogr 79:208-214

Ayón, P., Purca, S. and Guevara-Carrasco, R. (2004) Zooplankton volume trends off Peru between 1964 and 2001. ICES J. Mar. Sci Symp. Edition 61(4):478-484