TEST RESULTS

Dominion Consulting Pty Ltd ( Alistair McIlgorm) An Economic Appraisal of the Smart Tuna Hook System click here 

Discussion and conclusions

The size of the data sets from the trials was deemed sufficient for the productivity comparison at the individual vessel level. The comparison of the two treatments through regression analysis did not detect any results in which the difference between the control and the smart tuna hook treatments was significantly different. There was no evidence that the use of the STH either significantly increases, or significantly decreases, fish catch or catch value. This is an important result as fishers using the STH have some assurance that catch will not diminish, and that any benefits from reduced bird bycatch will benefit the fishing operation..............

The degree of bird impact reduction from the STH, and its application with other mitigations measures, makes the STH an attractive potential solution to this issue. The STH can enable vessels to operate with greater flexibility in fisheries where bycatch reduction is a requirement of operation. For example allowing the vessel to fish during daylight hours to target other species and or remove the need for weighted branch lines to increase crew safety and reduce capital costs of fishing gear.  Overall the expenditure on the STH can help fishers to maintain fishing access by minimizing bird bycatch within acceptable levels and without compromising fish catch.

Baker & Candy 2014 Smart Tuna Hook Proof of Concept Experiment click here 

Conclusion

We were able to demonstrate that the use of the Smart Tuna Hook led to a reduction in the bycatch
of seabirds of between 81.8% – 91.4% in one of the highest-risk fisheries to seabirds in the world
(Anderson et al. 2011; Petersen et al 2009). In a fishery where the bycatch rate of seabirds exceeded
1 bird/1000 hooks (this study), and where the capture of more than 25 birds by a vessel each season
leads to a suspension of fishing activity for that vessel, the Smart Tuna Hook offers an feasible option
for pelagic fishers to significantly reduce the level of interactions with seabirds and hence remain
active in the fishery. It clearly provided a significant deterrent to seabirds attacking baits.
While some forms of seabird bycatch mitigation are thought by fishers to impact the catch of
commercial target species, in our study there was no detectable difference between setting methods
in the catch rates of swordfish, yellow-fin tuna, big-eye tuna, southern Bluefin tuna, albacore tuna
and other commercially valuable species, indicating no detectable detrimental effect on fish catch
for any species. This provides confidence for fishers planning to use the Smart Tuna Hook that in
looking to reduce the risk of seabird bycatch their commercial operations will not be negatively
impacted. It stands to reason that if seabirds cannot readily access baited hooks because of the
protection provided by the STH shield, then bait retention will be improved and the probability of
catch of target species enhanced. There is some indication of this from previous work carried out in
the Coral Sea, Australia (Jusseitt 2010) but statistical demonstration of this would likely require
examination of many thousands of hooks under controlled experimental conditions. However, there
would appear to be immediate economic benefits to the South African Pelagic Longline Fishery of
using the STH and minimising seabird bycatch, thus greatly reducing the risk of a seasonal closures to
individual vessels and subsequent loss of income.

Innovation Case Study click here

Testing of the ‘Smart Hook’ Seabird By-catch Mitigation Device, by Barry Baker click here 

Conclusion

The performance of the Smart Hook was impressive in the presence of abundant and actively feeding seabirds. When deployed the baited hooks sank so quickly that I formed the opinion that many birds were barely aware that the baited hooks represented a food source.

The test protocol was to place baited smart hooks within 5 m. of foraging seabirds, but it was only when baits landed within a metre of birds that they displayed any real interest, and attempted to approach or attache a baited hook. Only six of the 136 birds presented with the smart hook managed to grasp a bait and attempted to feed upon it, but when this happened baits were not retained for long. In all cases squid baits were involved and birds appeared to break a piece oof the squid and let the remainder go, at which stage it sank.

The action of the birds attacking the bait did not dislodge the smart hook barrier and thus expose the birds to the risk of becoming hooked.

 

Responses of Sea Turtles to the Smart Hook, Dr. Kerstin Fritsches

Conclusion

The behavioural trials of captive turtles have shown that the Smart Hook successfully prevents both green and loggerhead turtles from getting hooked while interacting with the baited or unbaited device.

None of the animals tested were able to remove or destroy the shield despite frequent biting. Most animals showed curiosity and mouthed the device, however in all cases the animal’s initial aim was to remove and eat the bait from the device, which they were able to do without contact with the hook tip due to the shield. It was also noted that both green and loggerhead sea turtles actively use their front flippers to help remove bait from the hook, risking foul-hooking in the flippers or the soft flesh of the neck or base of the flipper.

The aim of this study was to test whether there was any difference in the effectiveness of the Smart Hook when using different hook and bait types and I found the Smart Hook to be effective in preventing hooking in all configurations tested.

The size of the shield in the Smart Hook will restrict the potential for swallowing to animals of larger carapace size exceeding 70cm for loggerhead sea turtles and close to 100cm for green turtles.

The large majority of loggerhead sea turtles interacting with longline gear appear to be below 70 cm (Bjorndale et al., 2003; Watson et al.2005) suggesting they would be too small to swallow the device. I note, however, that these size estimates were derived from oral anatomy measurements not accounting for active swallowing in the behaving turtle, which might allow somewhat smaller turtles to swallow the device. In the behavioural trials none of the turtles tested tried to swallow the device (max. carapace length 56cm).

The results obtained from the captive sea turtles outlined above demonstrate that the Smart Hook is a highly effective device to prevent hooking of the mouth and other body parts, of green and loggerhead sea turtles.

Operational Performance of the Smart Hook System in a Commercial Tuna Fishing operation, Hans Jusseit August 2010

Conclusion

The Smart Hook system was easily incorporated into the Tuna long-line fishing operations. The Smart Hook system performed well under all conditions experienced as well as some not expected.

The Smart Hook system can be easily included into Tuna long-line operations to mitigate the capture of seabirds and turtles. Analysis of the data shows the Smart Hook system increased the CPUE, increasing productivity and economic return.