The Wilson’s Phalarope Phalaropus tricolor population and feeding activity at Lake Titicaca

Abstract A population estimation of Wilson’s Phalaropes was conducted in the Confinada Lagoon of the inner bay of Lake Titicaca in the city of Puno between August and May of 2016/2017, 2017/2018 and 2018/2019. We employed the quadrat method of population estimation with three repetitions using 10×50 mm binoculars between 06:00 and 08:00 h. We recorded population fluctuations in August and September (immigration season) and April and May (emigration season). We counted a maximum population of 112,000 Wilson’s Phalaropes during the immigration season, and then in the emigration season. During their stay of approximately 8 months, the birds feed on water fleas, insects and detritus amounted to 146,496 t. The inner bay of Lake Titicaca is an important aquatic habitat for these migratory birds, which has a positive impact on the contribution to the decontamination of the lake.