Macrobenthic colonization on the derelict Fisheries Vessel Khronometer, Cristo Rey Submarine Park, Argentina

We investigated the fouling community on the Fisheries Vessel (F/V) Khronometer during a 3-year period, from its sinking, by means of video transects. The results demonstrate that the shipwreck presented high macroinvertebrate coverage from the first survey (100days after sinking). The most conspicuous organisms were cnidarians, followed by amphipods and serpulids (tubes). The hydroid Ectopleura crocea was the most abundant colonizer in the early stages; the sea anemone Anthothoe chilensis and the azooxanthellate soft coral Tripalea clavaria were abundant 2years after the vessel sank. Interestingly, shipwreck coverage and species composition at the end of the sampling period (940days after sinking) were similar to those of the wood vessel Cristo Rey, which sank 36years before the Khronometer. Besides, some different taxa from that seen on video transects were identified from samples taken during dives, corresponding to isolated organisms with scarce abundance or cryptic habits. Moreover, four reef fish species were recorded. Shipwrecks represent interesting places for recreational activities such as diving and fishing. This is the only study about the early development of an invertebrate community on artificial reefs in Buenos Aires coast, Argentina. Monitoring natural and artificial substrata could help to understand the ecological patterns occurring around them and provide information to help manage artificial reefs in sustainable ways.