Diet Composition of Purple Lagoon Crab Goniopsis pelii (Herklots, 1851) from South West Nigeria

Abstract

The crab family is the largest of the invertebrate phylum, the purple mangrove crab Goniopsis pelii (Herklots, 1951) collected from Lagos lagoon south west Nigeria were studied for insight in to their diet composition for the period between February and July, 2012. Of the three hundred and sixty (360) crabs examined (14.6%) had empty stomach while (85.4%) comprised of partially filled and filled stomach. The stomach contents of the crabs showed that they fed mainly on diatoms with a percentage occurrence of 42.4% and a numeric count of 40.3% while the least ingested food item was nematodes with a percentage occurrence of 0.2% and a numeric count of 0.09%. Other food items observed included algae, annelids, mollusc, plant parts, detritus, debris, crustaceans, fishes and sand grains. This research reveals the opportunistic dietary preference of Goniopsis pelii. The results will aid the understanding of the food ecology of Goniopsis pelii and will certainly provide a database for the food web dynamics of this lagoon crab in Nigeria.

Keywords: Purple Lagoon Crab, Lagos Lagoon, Diet.