TY - JOUR
T1 - Mass loss and macroinvertebrate colonisation of fish carcasses in riffles and pools of a NW Italian stream
AU - Fenoglio, Stefano
AU - Bo, Tiziano
AU - Agosta, Paolo
AU - Cucco, Marco
N1 - Funding Information:
We thank I. Borroni for the kind donation of trouts; L. Bellamy and M.S. Wipfli for useful suggestions and G. Malacarne for comments on the manuscript. This study was supported by Italian MURST grants.
PY - 2005/1
Y1 - 2005/1
N2 - In this study, we analysed the decomposition of trout carcasses in a low-order Apennine stream, with the aim to investigate the mass loss rate in a Mediterranean lotic system, and to examine the influence of microhabitats on the invertebrates colonising fish carcasses. In May 2003, we put 56 dead rainbow trout (Oncorhynchus mykiss) in the stream, placing seven sets (four trout each) in both riffle and pool habitats. At four dates, we removed one trout per set to measure its dry mass and determine the associated macroinvertebrate assemblage. Fifty-eight macroinvertebrate taxa colonised the carcasses, with significant differences between the erosive and depositional microhabitats. Riffle trouts hosted richer and denser colonist communities than pool trouts. Chironomidae, Serratella ignita, Habrophlebia sp., Dugesia sp. and Protonemura sp. were the five most abundant taxa. Decomposition was initially very rapid in both environments and then tapered off over time. The mass loss rate was higher (k= -0.057 day-1) than that found in other studies. Higher Mediterranean temperatures probably increase the process. Although we found no significant difference between riffles and pools, mass loss was more regular in erosive habitats, underlining the importance of local, small-scale conditions. In small, low-order, heterotrophic streams, fish carcasses represent an important resource and shelter for rich and diversified invertebrate assemblages.
AB - In this study, we analysed the decomposition of trout carcasses in a low-order Apennine stream, with the aim to investigate the mass loss rate in a Mediterranean lotic system, and to examine the influence of microhabitats on the invertebrates colonising fish carcasses. In May 2003, we put 56 dead rainbow trout (Oncorhynchus mykiss) in the stream, placing seven sets (four trout each) in both riffle and pool habitats. At four dates, we removed one trout per set to measure its dry mass and determine the associated macroinvertebrate assemblage. Fifty-eight macroinvertebrate taxa colonised the carcasses, with significant differences between the erosive and depositional microhabitats. Riffle trouts hosted richer and denser colonist communities than pool trouts. Chironomidae, Serratella ignita, Habrophlebia sp., Dugesia sp. and Protonemura sp. were the five most abundant taxa. Decomposition was initially very rapid in both environments and then tapered off over time. The mass loss rate was higher (k= -0.057 day-1) than that found in other studies. Higher Mediterranean temperatures probably increase the process. Although we found no significant difference between riffles and pools, mass loss was more regular in erosive habitats, underlining the importance of local, small-scale conditions. In small, low-order, heterotrophic streams, fish carcasses represent an important resource and shelter for rich and diversified invertebrate assemblages.
KW - Decomposition
KW - Macroinvertebrate colonisation
KW - Pools
KW - Riffles
KW - Trout carrion
UR - http://www.scopus.com/inward/record.url?scp=19944389318&partnerID=8YFLogxK
U2 - 10.1007/s10750-004-9451-2
DO - 10.1007/s10750-004-9451-2
M3 - Article
SN - 0018-8158
VL - 532
SP - 111
EP - 122
JO - Hydrobiologia
JF - Hydrobiologia
IS - 1
ER -