Seabird bycatch in New Zealand fisheries

Summary of recent research on seabird bycatch in New Zealand fisheries, presented at the 5th International Albatross and Petrel Conference, welling, New Zealand.

Transcript

1. Seabird bycatch in New Zealand fisheries Edward Abraham edward@dragonfly.co.nz IAPC, Wellington 14 August 2012
2. Observer data • New Zealand fisheries monitored by Government observers • Observers record seabird bycatch • In the 2009 fishing year, there were 586 seabird captures reported by fisheries observers from fisheries operating within New Zealand waters Observer photograph of a white-capped albatross killed during squid trawling
3. Estimating seabird bycatch Darryl Crimp, Albert Times 14 (2007)
4. Estimation has a narrow question How many captures would have been reported, had all fishing been observed? Limitations • Only sufficiently observed fisheries • Only for individual species with high observed captures • No cryptic mortality • Not related to demographic status • No consideration of other impacts A synthesis requires a risk assessment approach Front window of a pie shop in Bluff
5. Photograph thanks to David Thompson
6. 200 200 200 200 200 200 200 500 500 500 500 500 500 500 500 1000 1000 q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q qq q q q q q > 100 tows 10 − 49 tows 1 − 4 tows q q q > 20 obs tows 5 − 19 obs tows 2 − 4 obs tows q observed captures Observed white capped albatross bycatch in squid trawl fisheries, 2009; 53 observed captures
7. Trawl fishing effort and observed captures 1999 to 2009 0 40 80 120 Hundreds of tows 99 00 01 02 03 04 05 06 07 08 09 Fishing year 0 10 20 30 40 % tows observed Observed Unobserved Coverage 0 100 200 Observed captures 99 00 01 02 03 04 05 06 07 08 09 Fishing year 0 2 4 6 8 Captures per 100 tows Dead Alive Rate
8. Estimated captures of white capped albatross All EEZ, all offshore trawl fisheries White-capped albatross • Captures of 776 (624–968) in 2005 • Fell to 156 (118–205) in 2009 q q q q q q q Fishing year Captures q q q q q q q 03 04 05 06 07 08 09 0 200 400 600 800 1000 1200 Capture rate of white-capped albatross in the Auckland Islands squid fishery
9. White capped albatross capture rate Auckland Islands squid trawl Reduced capture rate • Sandy Bartle recorded 27.9 captures per 100 tows in 1991 • Mean capture rate of 9.4 from 2003 to 2005 • Mean capture rate of 4.1 from 2006 to 2009 2003 2004 2005 2006 2007 2008 2009 Fishing year Capture rate (birds per 100 tows) 0 5 10 15 Capture rate of white-capped albatross in the Auckland Islands squid fishery
10. 200 200 200 200 200 200 200 500 500 500 500 500 500 500 500 500 500 500 500 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q qq q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q > 100 tows 10 − 49 tows 1 − 4 tows q q q > 20 obs tows 5 − 19 obs tows 2 − 4 obs tows q observed captures Observed seabird bycatch in trawl fisheries, 2009 Sooty shearwater 127 White chinned petrel 86 White capped albatross 78 Spotted shag 32 Salvin’s albatross 29 Buller’s albatross 19 Flesh footed shearwater 3 Cape petrel 4 Westland petrel 2 Chatham albatross 1 ...
11. Estimated seabird bycatch Offshore trawl 2003 2004 2005 2006 2007 2008 2009 0 1000 2000 3000 4000 Number of captures Albatrosses Petrels All birds
12. 200 200 200 200 200 500 500 500 500 500 500 500 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q qq q q q q q q >105hooks 104−105hooks 103−104hooks q q q >2 × 104obs hooks 104−2 × 104obs hooks <104obs hooks q observed captures Observed seabird bycatch in pelagic longline fisheries, 2009 Buller’s albatross 29 Grey petrel 6 White capped albatross 3 White chinned petrel 3 Salvin’s albatross 3 Black petrel 2 Black browed albatross 2 Wandering albatross 2 Cape petrel 1 Westland petrel 1 Antipodean albatross 1 Campbell albatross 1 Gibson’s albatross 1 Northen royal albatross 1
13. Estimated seabird bycatch Pelagic longline 2003 2004 2005 2006 2007 2008 2009 0 500 1000 1500 2000 2500 3000 Number of captures Albatrosses Petrels All birds
14. 200 200 200 200 200 200 200 200 200 500 500 500 500 500 500 500 500 500 500 500 500 500 500 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q q >105hooks 104−105hooks 103−104hooks q q q >2 × 104obs hooks 104−2 × 104obs hooks <104obs hooks q observed captures Observed seabird bycatch in demersal longline fisheries, 2009 Flesh footed shearwater 13 Black petrel 8 Grey petrel 3 Cape petrel 2 Penguins 2 White chinned petrel 1 Salvin’s albatross 1 Chatham albatross 1 Black backed gull 1 Buller’s shearwater 1
15. Elizabeth Crapo, NOAA, public domain
16. Demersal longline effort and captures White chinned petrel, 1999 to 2009 0 20000 50000 Thousands of hooks 99 00 01 02 03 04 05 06 07 08 09 Fishing year 0 10 20 30 % hooks observed Observed Unobserved Coverage 0 100 300 Observed captures 99 00 01 02 03 04 05 06 07 08 09 Fishing year 0.00 0.02 0.04 Captures per 1000 hooks Dead Alive Rate
17. Estimated captures of white chinned petrel All EEZ, large vessel demersal longline fisheries High uncertainty • Estimated captures of 1025 (595–2179) in 2002 • Fell to 371 (36–1366) in 2009 • Mean estimate of integrated weight line effect of 12.8% • Observations biased to vessels that use integrated weight line q q q q q q q q q q q Fishing year Captures q q q q q q q q q q q 99 00 01 02 03 04 05 06 07 08 09 0 1000 2000 3000 4000 Captures of white chinned petrel in demersal longline
18. Estimated seabird bycatch large vessel and snapper demersal longline 2003 2004 2005 2006 2007 2008 2009 0 500 1000 1500 2000 2500 Number of captures Albatrosses Petrels All birds
19. Estimated bycatch in commercial fisheries Currently around 4 000 captures annually 2003 2004 2005 2006 2007 2008 2009 0 2000 4000 6000 8000 Number of captures Albatrosses Petrels All birds Offshore trawl, pelagic longline, large vessel and snapper demersal longline
20. Recreational fisheries Over 10 000 captures annually • Carried out 763 boat ramp interviews; 21 people reported a seabird capture on the day of the interview • In the Hauraki Gulf, there are 4 million hours of fishing annually • Translates into 11 500 (95% c.i.: 6 600 to 17 200) seabird captures • A thumb-suck of 40 000 captures nationally, from telephone survey estimates of the amount of fishing • Post-capture survival unknown A giant petrel gets the gurnard, Herb Spannagal, Fishing News
21. Acknowledgments Thanks to the many, many people who work to solve this problem MPI All the observers who put in the time at sea, Nathan Walker, Rohan Currey, Martin Cryer, the database team Sextant Technology Susan Waugh, Dominique Filippi Dragonfly Finlay Thompson, Katrin Berkenbusch, Yvan Richard JPEC Johanna Pierre AEWG All the working group members for keeping us honest Photographs David Thompson, Duncan Wright for the Buller’s albatross in the banner (CC-BY-SA), DOC, MPI Finding out more All research available from http://dragonfly.co.nz/publications.html