The rainy season is actually limatik season – a period when land leeches are abundant. Why is this so? Nobody really knows because nobody has really studied the population dynamics of land leeches. My guesses include: (1) Abundant rain not only make the surroundings wetter but also protects leeches from dessication;(2) Resting stages of leeches are probably stimulated into “waking up” by the series of rains; (3) More lush vegetation during the rainy season favor more herbivorous mammals to feed more often and, hence, more chances for leeches to feed; (4) The rains bring both wetter forest litter and a blush of new leaves and shoots where land leeches can anchor themselves unnoticed as they wait for their unsuspecting blood donors.
Overall, the Hirudinea, the class that embraces all leeches, both the terrestrial kinds (limatik) and the aquatic (linta), includes almost 700 species. Land leeches are chiefly from the warm and humid regions near the equator or the tropics and subtropics. They are more commonly seen in mountains, forests, wastelands, as well as areas near rivers and ponds. Sometimes mudpits (lubluban) of carabaos (water buffaloes) are inhabited by both water-dwelling and land leeches.
My searches for insects has brought me to many destinations and in those unforgettable places, leeches are a given – from my favorite Mount Makiling to Mount Banahaw, especially on the Lucban side; Mount Malasimbu in Mindoro; the Philippine National Botanic Gardens (now UP Quezon Land Grand) in Real, Quezon; the areas surrounding Cavinti Underground River and Cave Complex in Cavinti, Laguna, up to across the Lalangawan River, said to be politically part of Mauban, Quezon; Mount Apo, on the side of Kidapawan, North Cotabato; Mount Pangasugan, in Baybay, Leyte etc. Clean air, lush forests, nicest views, and yes, hungry leeches. They taught me important lessons: that our rich biodiversity also has its price (from the human-centered point of view and – “Everything is beautiful in its own way.“ – Jun Lit