What is left behind when the lights go off? Comparing the abundance and composition of litter in urban areas with different intensity of nightlife use in Mar del Plata, Argentina

• Litter was assessed in urbanized areas with different intensity of nightlife activities.
• Cigarette butts, papers, and plastics were the items most commonly littered in the study area.
• Nightlife activities need to be taken into account when considering local urban planning.

Nightlife activities represents an important source of urban litter; the latter often being left behind or abandoned in public places and streets. Mar del Plata is a very important city on the Atlantic coast of Argentina and is the main tourism destination in the South Atlantic region of South America. However, few studies on urban litter related to nightlife activities have been conducted in the area. Here we assessed (i) the abundance and composition of litter, and (ii) the spatial and temporal variations of its abundance, diversity, richness and evenness in urbanized areas with different intensity of nightlife activities from April 2008 to March 2009. An overall of 13,503 items were counted. Around 92% of the total litter was comprised by cigarette butts, papers and plastics. We found significant spatial differences in the abundance of litter between sampling sites, with the greatest amounts of litter at the Alem site followed by the Hipólito site (both with an intensive nightlife activity) compared with the Chauvin site (a quiet high-income neighborhood). The composition of litter of the Alem and the Hipólito sites was relatively similar and both sites differ with respect to the Chauvin site. Cigarette butts, papers, and plastics were the items that contributed most to the dissimilarity between sampling sites. The diversity of litter was the single community parameter that significantly differed from the other seasons. We discussed the potential effect of nightlife activities on the amounts and quality of urban litter in the city of Mar del Plata.