It has been reported that the number of bird species found in the sanctuary has been reduced to nearly half in less than seven years.
Human interferences may be contributing to the dwindling number of birds arriving at Mangalavanam Bird Sanctuary (MBS), said Forest Department officials. It has been reported that the number of bird species found in the sanctuary has been reduced to nearly half in less than seven years. A study carried out by P.S. Easa and E.A. Jayson of the Kerala Forest Research Institute, Thrissur, in 1999, had recorded the presence of 72 species of birds from MBS.