TY - JOUR
T1 - Effect of stocking density on the dynamics of cannibalism in sibling larvae of Perca fluviatilis under controlled conditions
AU - Baras, E.
AU - Mélard, C.
AU - Kestemont, P.
N1 - Copyright 2008 Elsevier B.V., All rights reserved.
PY - 2003/4/2
Y1 - 2003/4/2
N2 - The effect of stocking density (10, 31.6 and 100 larvae 1; three replicates per treatment) on the day-by-day dynamics of survival, growth and cannibalism was examined in sibling perch larvae reared from eyed-egg stage in 100-1 cages (16L:8D, 20.0 ± 0.5°C, O ≥ 6.0 mg 1; feeding in excess with live Artemia nauplii during the photophase) during the first 3 weeks of exogenous feeding. Larvae unable to achieve the transition to exogenous feeding died in between 7 and 11 days post-hatch. Later, mortality from causes other than cannibalism never exceeded 1% day. Cannibalism did not start before days 10-11 and first consisted in the incomplete ingestion of prey attacked tail first, exclusively. This type of cannibalism never caused losses higher than 2.0% of the initial stock, and ceased after days 16-18. From days 12-14 onwards, differential growth was apparent, and cannibals turned to complete cannibalism of small prey ingested head first, which caused greater losses (28-53% of the stock). Increasing the stocking density did not compromise growth and decreased the overall impact of cannibalism through several complementary mechanisms: (i) a postponed emergence of cannibalism, (ii) a lower proportion of cannibals in the population, and (iii) probably a lower rate of cannibalism per capita as predation was complicated and less directed at high stocking density.
AB - The effect of stocking density (10, 31.6 and 100 larvae 1; three replicates per treatment) on the day-by-day dynamics of survival, growth and cannibalism was examined in sibling perch larvae reared from eyed-egg stage in 100-1 cages (16L:8D, 20.0 ± 0.5°C, O ≥ 6.0 mg 1; feeding in excess with live Artemia nauplii during the photophase) during the first 3 weeks of exogenous feeding. Larvae unable to achieve the transition to exogenous feeding died in between 7 and 11 days post-hatch. Later, mortality from causes other than cannibalism never exceeded 1% day. Cannibalism did not start before days 10-11 and first consisted in the incomplete ingestion of prey attacked tail first, exclusively. This type of cannibalism never caused losses higher than 2.0% of the initial stock, and ceased after days 16-18. From days 12-14 onwards, differential growth was apparent, and cannibals turned to complete cannibalism of small prey ingested head first, which caused greater losses (28-53% of the stock). Increasing the stocking density did not compromise growth and decreased the overall impact of cannibalism through several complementary mechanisms: (i) a postponed emergence of cannibalism, (ii) a lower proportion of cannibals in the population, and (iii) probably a lower rate of cannibalism per capita as predation was complicated and less directed at high stocking density.
UR - http://www.scopus.com/inward/record.url?scp=0037414008&partnerID=8YFLogxK
U2 - 10.1016/S0044-8486(02)00349-6
DO - 10.1016/S0044-8486(02)00349-6
M3 - Article
AN - SCOPUS:0037414008
SN - 0044-8486
VL - 219
SP - 241
EP - 255
JO - Aquaculture
JF - Aquaculture
IS - 1-4
ER -