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Fishery Bulletin 108(3) 
the fishery and environmental indices and subsequent 
statistical analyses. 
Logbook (database 1) 
During the “Programme Palangre Reunion” (PPR), a 
rigorous data-collecting strategy was implemented. 
Logbooks were distributed to all domestic vessels, along 
with species identification guides, including guides 
for identifying sharks and sea turtles. Because these 
logbooks were completed on a voluntary basis, logbook 
data were cross checked against landing receipts to 
estimate the monthly logbook coverage. Logbook data 
made up the major source of information used to ana- 
lyze the effect of operational and gear-setting practices 
on catches. 
Analyses focused on data collected between 1998 and 
2000 and which encompassed several lunar cycles. Log- 
book submission was high by the domestic fleet and the 
fleet operated between 20° and 23°S lat. and 53° and 
57° long. (Fig. 2, area D). Database 1 consisted of 2009 
longline sets where seven species were easily identified: 
albacore, bigeye and yellowfin tuna, dolphinfish, sword- 
fish, blue ( Prionace glauca ) and oceanic whitetip sharks 
( Carcharhinus longimanus), and three broader shark 
species groups (mako sharks [Isurus spp.], hammer- 
head sharks [Sphyr?ia spp.], and other sharks grouped 
together as “mixed sharks”). 
Experimental fishing (databases 2 and 3) 
Fish behavior on a daily scale (fine scale) was investi- 
gated on portions of the longlines equipped with hook 
timers to estimate fish capture time and with time- 
depth recorders (TDRs) attached in the middle position 
between two consecutive floats, which is theoretically 
the deepest point reached by the mainline. On 160 
sets, 284 TDRs were used to estimate hook depth (TDR 
depth+branchline length). The number of hook timers 
deployed per set varied from 61 to 408 according to the 
boat size and weather conditions. For thirty-three trips, 
28,974 hook timers were used during 160 sets. These 
experimental data constituted database 2. The time 
between the setting of the hook and capture time was 
represented as a capture index and stratified into four 
classes (0-4 h, 4-7 h, 7-10 h and >10 h). Database 3 
