Waterbird Declines are Consistent with Increasing Kitesurfing Activity in a Uruguayan Coastal Lagoon

Outdoor recreational activities are widely regarded as significant threats to both migratory and resident waterbirds, many of which are experiencing population declines. Emerging water sports like kitesurfing have the potential to disturb waterbirds, yet limited information is currently available on their impacts. In order to help address this knowledge gap, we evaluated whether a relationship exists between kitesurfing activity and changes in waterbird abundance over time in Laguna Garzon, Uruguay. Generalized linear models were fitted using a database of 19 systematic bird counts, conducted twice a year in summer and winter between 2005 and 2019. In addition, a survey of 75 kitesurfers who use the lagoon was conducted to assess usage patterns of the area. We found that the abundance of birds at the site drastically decreased during 15 years as the influx of kitesurfers increased. The decrease was only in the waterbirds that use the body water or shorelines and it was more accentuated in summer, coinciding in space and time with kitesurfing activity. These results are consistent with a negative impact of kitesurfing on birds, although other factors may have contributed. We conclude that further research on kitesurfing activity in the lagoon is needed to develop regulatory practices that balance recreational use with bird conservation.