Fisheries

Question 1

FAO

Answer 1

Around 80mt are taken from the sea every year.

Question 2

Votier et al (2013)

Answer 2

Using GPS and camera mounted on birds they tracked 10 gannets from Grossholm Island in Wales during July 2011. All birds interacted with trawling vessels, all about >15m and were always accompanied by other scavenging birds. Discard bans could have detrimental effects.

Question 3

Bartumeus et al (2010)

Answer 3

Balearic Shearwaters tended to change their spatio-temporal feeding patterns based on trawling activity. In the Med where trawling is prohibited on weekends the birds travelled further distances to find food where as during the week the demonstrated high site fidelity and stuck close to the vessels.

Question 4

Merkel (2010)

Answer 4

Birds in the Nordic sea collided with vessels which was gathered from observation data on traweling, cargo and navy boats. 41 incidents were recorded over 2 winters and 88 birds were killed within one incident.

Question 5

Fredenksen et al (2004)

Answer 5

Black-legged kittiwakes in the North Sea showed declines of up to 50% when the sand eel fisheries were active. Surveys of populations were undertaken and adult survival, colony size and reproductive success measured. Adult survival and reproductive success was much lower during times when the fishery was active.

Question 6

Jahncke et al (2004)

Answer 6

After a strong upelling in the mid 1990s the Peruvian anchovian fishery became highly active and is estimated to have taken at leats 85% of the resident anchovies from the area which resulted in a steep decline in guano making birds such as boobys, cormorants and pelicans.

Question 7

Bjorke et al (2013)

Answer 7

6,900 harbour seals were estimated to have been caught per year over a two year study off the coast of cnetral Norway in gill net fisheries.

Question 8

Stevens (1992)

Answer 8

70 Japanese longline fisheries operating outside the EEZ around Tasmanian waters are intending to catch tuna but catch as many as 35,000 blue sharks while longing which are de-finned before being thrown back in to the ocean . Mainly immature and adolescent females.

Question 9

Kraus et al (1997)

Answer 9

In the Golf of Maine a controlled experiment was carried out and by placing pingers of shipping vessels or around stationary nets it was established that porpoise bycatch reduced by 92%.

Question 10

Read (2006)

Answer 10

Experiment using circle hooks instead of J hooks in fisheries around the Azores, North Atlantic and Ecudor. Significantly reduced the amount of turtle bycatch.

Question 11

Sancho et al (2003)

Answer 11

Deliberately deployed 27 in the Cantabrain Sea around depths of 110-135m. Recovered nets at monthly intervals. Unmanned nets caught the same as manned nets, which worked out at around 17.5kg per 100m of netting.

Question 12

Humborstad et al (2003)

Answer 12

Deliberately lost nets off the coast of Norway in July and Jnne 2003. Estimated that 28-43kg per gillnet fleet were being caught in ghost nets.

Question 13

Gregory (2009)

Answer 13

Humpack whales and fishing nets