Determinación de la composición y abundancia de almejas de los Géneros Protothaca y Chione en una zona intermareal en el estuario del río Chone

Abstract

The abundance and composition Protothaca and Chione clams were studied in 500 m2

intertidal area the Chone river estuary from May to November 2009. The samples were collected fortnightly, from May to November, by random collection with a 1 m2 standard quadrate. Temperature, salinity, pH and dissolved oxygen were recorded. One Chione and five Protothaca were found obtaining two thousand eight hundred and fifty nine clams, beining 749 (26,20 %) Chione subrugosa and 586 (20,50 %) Protothaca asperrima. The size ranges for Chione subrugosa osciled between 15 to 39 mm total length, with length averages of 28,25 ± 0,27 mm and weight average of 12,32 ± 0,30 g; for Protothaca asperrima ranges from 15 to 45 mm with average of 32,82 ± 0,38 mm of total length and averages total weight of 15,89 ± 0,44 g. The total weight (Wt) and total length (Lt) relation for Chione subrugosa was represented for the equation Pt = 0,004 Lt2,333 (r2= 0,765) and for Protothaca asperrima Pt = 0,008 Lt2,161 (r2 = 0,716). The average production for Chione subrugosa was 11,43 ± 0,37 g/m2 with average density of 3,06 ± 0,33 clams /m2 in contrast Protothaca asperrima presented an average production of 14,52 ± 0,58 g/m2 and an average density of 2,53 ± 0,33 clams /m2 showing significative differences between months (p < 0,05).