Seabird and Shark Bycatches in the Pacific Ocean from Taiwanese Observer Data of 2002-2005 ********...
-
Upload
audrey-terry -
Category
Documents
-
view
217 -
download
1
Transcript of Seabird and Shark Bycatches in the Pacific Ocean from Taiwanese Observer Data of 2002-2005 ********...
Seabird and Shark Bycatches in the Pacific Ocean from Taiwanese Observer Data of 2002-
2005
********
Shui-Kai Chang, Ju-Ping Tai & Chih-Hao
Shiao
Observer Program was launched on Taiwanese LL in the Pacific
Ocean since 2002
-------------------------------
Altogether 13 observation trips during 2002-05
4 on ALB vessels – in temperate region
9 on BET vessels – in tropical region
Year No. Obs No. Vessel Total efforts Fishing days
2002 1 1 186 65
2003 2 3 653 183
2004 2 4 1066 324
2005 4 5 982 308
E 120 140 160 180 160 140 120 100 80 W
40
20
0
20
40N
S
E 120 140 160 180 160 140 120 100 80 W
40
20
0
20
40N
SE 120 140 160 180 160 140 120 100 80 W
40
20
0
20
40N
S
2003
2004 2005
E 120 140 160 180 160 140 120 100 80 W
40
20
0
20
40N
S
2002
> 100 50 - 100 25 - 50 5 - 25 0 - 5
1000 Hooks
> 100 50 - 100 25 - 50 5 - 25 0 - 5
1000 Hooks
> 100 50 - 100 25 - 50 5 - 25 0 - 5
1000 Hooks
> 100 50 - 100 25 - 50 5 - 25 0 - 5
1000 Hooks
Tunas Billfishes Sharks Other fishes Seabirds
Year No. % No. % No. % No. % No. %
2002 2,374 83.36 147 5.16 81 2.84 246 8.64 0 0.00
2003 11,672 87.44 202 1.51 365 2.73 1,094 8.20 15 0.11
2004 12,253 88.11 519 3.73 733 5.20 518 3.72 6 0.04
2005 15,028 82.02 970 5.29 876 4.78 1,438 7.85 9 0.05
ALB
BET
YFT
SWO
BIL
SKJ
OTH
SEABIRDS
Ranged between 0.00-0.11% to the total catches
Seabird
Overall EPO
Year No. Catch rate No. Catch rate
2002 0 0.000 0 0.000
2003 15 0.023 1 0.004
2004 6 0.006 1 0.003
2005 9 0.009 6 0.016
E 120 140 160 180 160 140 120 100 80 W
40
20
0
20
40N
S
E 120 140 160 180 160 140 120 100 80 W
40
20
0
20
40N
SE 120 140 160 180 160 140 120 100 80 W
40
20
0
20
40N
S
2003
2004 2005
>=4 3 2 1
Sea bird
>=4 3 2 1
Sea bird
>=4 3 2 1
Sea bird
Laysan albatross
Black-browed albatross
Amsterdam albatross
Giant petrel
Petrels
Others
For 2004-05 when new observer logbook adopted
Year TotalAlive and released
Dead and discarded
2002 0 0 0
2003 15 1 14
2004 6 1 5
2005 9 1 8
Total 30 3 (10%) 27 (90%)
Frigitbirds
Albatr-osses
Others
Tropical Region
Others
Petrels
Albatrosses
Temperate Region
N=519
N=2819
SHARKS
Ranged between 2.73-5.20% to the total catches
Shark
Overall EPO
Year No. Catch rate No. Catch rate
2002 81 0.436 42 0.507
2003 365 0.559 267 0.987
2004 733 0.688 391 1.250
2005 876 0.892 285 0.745
E 120 140 160 180 160 140 120 100 80 W
40
20
0
20
40N
S
E 120 140 160 180 160 140 120 100 80 W
40
20
0
20
40N
SE 120 140 160 180 160 140 120 100 80 W
40
20
0
20
40N
S
2003
2004 2005
E 120 140 160 180 160 140 120 100 80 W
40
20
0
20
40N
S
2002
>100 50-100 25-50 10-25 1-10
Shark
>100 50-100 25-50 10-25 1-10
Shark
>100 50-100 25-50 10-25 1-10
Shark
>100 50-100 25-50 10-25 1-10
Shark
Blue shark
Silky shark
Shortfin mako
Oceanic whitetip shark
Pelagic thresher
Bigeye thresher
Other shark
308 fish: 286 (2004-05) + 22 (2006) 80% from blue shark and 10% from silky shark shark-fin-ratio varies significantly by species
and by the way the shark carcasses are processed
100 80W
40
S50
30
N40
30
20
10
0
10
20
E140 160 180 160 140 120
鯊魚還原係數採樣分布2004~2006
> 10
5 to 10
2 to 5 < 2
Brief Introduction to the 2006 Workshop on
Reduction of Sea Turtle Incidental Catch
60 peoples from industry and government
Topics
(1) World actions to conserve sea turtles
(2) The endangered sea turtles
(3) Results from circle hooks experiments
(4) The usage of de-hooker
(5) Invitation for large scale circle hooks experiments
7 Atlantic LL and 3 Pacific LL enrolled