IMPOSEX INCIDENCE IN Thais tuberose (Roding, 1798) Cronia margariticola (Broderip, 1832) IN THE COASTAL BARANGAYS OF NASIPIT, AGUSAN DEL NORTE, PHILIPPINES

Abstract

The imposex incidence in Thais tuberose (Roding, 1798) and Cronia margariticola (Broderip, 1832) were studied to assess the incidence of imposex in the coastal Barangays of Nasipit, Agusan del Norte. Almost all sites were showed incidence of imposex development. The most affected and highest incidence of imposex using T. tuberose and C. margariticola is Brgy. Camagong with the value of 73.33% and 66.66% in Incidence of Imposex (IOI); 32.35% and 34.21% in Conversion of Potential Female of Imposex Index (CPFII); and in Relative Penis Length Index ( RPLI) of 72.10 and 61.71% respectively. Followed by Sta. Ana, Apagan, Punta, Amontay have the most cases of imposex. The study identified higher occurrences of imposex near and adjacent the shipyard. Results showed that T. tuberose is more sensitive to imposex compared to C. margariticola, thus, suggesting a better bioindicator.