Reproductive biology of the mudskippers Boleophthalmus boddarti and Periophthalmus novemradiatus in the Indian Sundarbans

Reproductive biology of mudskippers Boleophthalmus boddarti and Periophthalmus novemradiatus are investigated along the mudflats of the Indian Sundarbans. We investigated a total of 794 sampes for both male and female Boleophthalmus boddarti and Periophthalmus novemradiatus fish species to explore properties such as the size-at-50% maturity, fecundity, spawning, gona-dosomatic and hepatosomatic indices along with the characterization of the macroscopic and histological attributes of the female gonads. Our work reports for the first time the weight-length relationships for these fish species in the Sundarbans region depicting a negative allometric growth pattern. The size-at-50% maturity which is often a crucial parameter for stock and reserve management is found for the female and male Boleophthalmus boddarti as 10.2 cm and 9.9 cm respectively, whereas, for the Periophthalmus novemradiatus, the same were 4.0 cm and 4.4 cm, respectively. Fully matured female Boleophthalmus boddarti were found to be multiple spawners in comparison to Periophthalmus novemradiatus with monthly variation of Le Crens relative condition [≤]1, indicating good physiological conditions of the fish. The relationships between batch fecundity (F), body weight (i.e., BW, gm) and total length (i.e., TL, cm) were Log10F = 1.12 Log10BW + 2.41 and Log10F = 1.93 Log10TL + 1.82, respectively for Boleoph-thalmus boddarti and for the Periophthalmus novemradiatus, it was Log10F = 2.15 Log10BW + 2.57 and Log10F = 5.43 Log10TL - 0.81. The reproductive parameters estimated in this study are important information for studying population dynamics and stock assessments of these mudskippers in the Indian Sundarbans and will contribute to the management, conservation and prediction of environmental changes as these mudskippers are often studied as bio-indicators for climate-change effects.