Influence of Seabird Colonies on Soil Macrofauna Communities at the Black Sea Coast Forests

Abstract

A seabird (Phalacrocorax carbo) colony overwintering for three consecutive years in a pine forest near the Black Sea coast caused severe damage to the vegetation. The impact of excessive nutrients input from this colony increased soil acidity, N, P, Cu and S-content in soil and might therefore affect soil macrofauna. We compared the abundance of main functional trait guilds and the total abundance of soil macrofauna within impact and control pine forests. No significant difference between the sites was noted in taxonomic richness, total macrofauna abundance and abundance of mobile, belowground, phytophagous and predatory invertebrates. However, the abundance of poorly mobile, poorly mobile epibiontic, and these both traits of saprophagous macrofauna guilds was significantly higher in the control sites. We conclude that three-year wintering of a seabird colony in forest can lead to drastic changes in the macrofauna communities structure due to allochthonous input of nutrients.