The hook pod protects the point and barb of baited hooks from seabird attack during line setting. Branch line weighting at the hook maximises hook sink rate. When a predetermined depth is reached a pressure release system ensures that the pod opens, releasing the hook to begin fishing. The pod is retrieved during hauling, closed and stored until the next set.
The hook pod incorporates a light emitting diode (LED) light source that is triggered by a magnetic switch when the device opens at depth. The LED is incorporated as an alternative to disposable chemical light sticks (reducing marine debris) and electric fishing lights.
Experimental research on the efficacy of the hook pod in reducing bycatch of seabirds has been conducted across a range of pelagic fisheries (southern Brazil, South Africa and Australia) over a four-year period, evaluating variables including bait type, hooking position and hook sink rate [1,2]. It has been shown to significantly reduce seabird bycatch without negatively affecting target catch rates [1,3].
The Hook Pod has been assessed by ACAP (September 2017) and included in their list of best practice measures for mitigating seabird bycatch in pelagic longline fisheries . This is conditional upon the device meeting certain performance requirements, noted below:
'Hook Pod’ – 68 g minimum weight that is positioned at the hook, encapsulating the barb and point of the hook during setting, and remains attached until it reaches 10 m in depth, when the hook is released.
Research conducted in three different regions showed that the hook pod did not increase bycatch of other taxa. Preliminary findings suggest hook pods may reduce marine turtle bycatch but further data is needed to validate this .
Hook pods readily fit into standard line storage, setting and hauling operations. There has been ongoing refinement of the ergonomic shape of the pod, to ensure ease of handling, and minimise entanglements with monofilament branchlines during fishing operations . The devices are more easily fitted when the branch line is being built, prior to the hook being crimped onto the branch line, rather than by retro-fitting the device onto existing branch lines .
While not yet commercially available, commercial tooling has been completed. It is estimated that each hook pod will cost around AUD 17.00. A small version of the hook pod that does not contain a LED is being developed. It will cost approximately AUD 10.00. Details of potential cost savings in fisheries where chemical lightsticks are used can be found in Barrington (2016).
The hook pod replaces branch line weighting using lead weights and/or swivels, with associated cost savings .
Monitoring, control and surveillance of the Hook Pod technology could be achieved through onboard observer programs, use of electronic monitoring systems that monitor setting operations and in port inspections. Once Hook Pods are purchased and fitted they are effectively integral to the gear, and this may be verified by visual inspection .
Further field research is required to evaluate the relative contributions of the sink rates and hook protection components of the hook pod in reducing bycatch. The possibility of increased rates of bird entanglement has been signalled as a concern, as deployment of the hook pod creates a loop of branch line during setting .
- Barrington, J. 2016. “Hook Pod” as best practice seabird bycatch mitigation in pelagic longline fisheries. In ACAP - Seventh Meeting of the Seabird Bycatch Working Group, La Serena, Chile: ACAP-SBWG7-Doc10.
- Sullivan, B.J., Kibel, B., Kibel, P., Yates, O., Potts, J.M., Ingham, B., Domingo, A., Gianuca, D., Jiménez, S., Maree, B.A., Neves, T., Peppes, F., Silva-Costa, A. and Wanless, R.M. (In review). Hook Pod: development and at-sea trialling of a ‘one-stop’ mitigation solution for seabird bycatch in pelagic longline fisheries. Submitted to PLOS One.
- Sullivan, B.J., Kibel, P., Kibel, B., Yates, O., Potts, J., and Birdlife Albatross Task Force. 2016. Hook Pod: development and at-sea trialling of a “one-stop” mitigation solution for seabird bycatch in pelagic longline fisheries. In ACAP - Seventh Meeting of the Seabird Bycatch Working Group, Serena, Chile: ACAP-SBWG7-Inf-06.
- ACAP. 2017.ACAP Review and Best Practice Advice for Reducing the Impact of Pelagic Longline Fisheries on Seabirds. Tenth Meeting of the Advisory Committee, Wellington..