90 
Fishery Bulletin 116(1) 
knowledge these stocks as separate stocks may lead to 
flawed management actions and ultimately to overex¬ 
ploitation. However, the results obtained here suggest 
that there may be a mix (below 32% misclassification) 
of individuals of different stocks, namely between Ma¬ 
deira and the Canary Islands, which could offer a buf¬ 
fer against any regional overexploitation. This finding 
implies that, for an accurate assessment of the over¬ 
all population and state of each stock, its boundaries 
should not only be defined but also an estimate should 
be made of the proportion of mixing of fish from the 
different population units, by location and time of year 
during which the mixing of stocks occurs (Murta et al., 
2008b). 
Acknowledgments 
JV was supported by Regional Agency for the Devel¬ 
opment of Research Technology and Innovation (Pro¬ 
gramme RUMOS, PhD grant—Project 22/1080/1974). 
VS was supported by a grant from the ‘Fundafao para a 
Ciencia e a Tecnologia’ (FCT) (SFRH/BPD/108917/2015). 
This study had also the support of FCT, through the 
strategic project UID/MAR/04292/2013 granted to 
MARE and the Oceanic Observatory of Madeira proj¬ 
ect (M1420-01-0145-FEDER-000001—‘Observatorio 
Oceanico da Madeira’—OOM). 
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