How to Build:
The frame of the BIOPOLE is constructed from a cylindrical fiberglass rod (2 cm diameter,1.5 m long). A 2 x 3 cm PVC end cap (1.27 cm schedule 40) is fixed to the end of each fiberglass rod with epoxy glue and drilled at the center with a 5 mm (wide) x 15 mm (deep) hole to house the steel tissue extraction probe. The base of each rod is fitted with a band of elastic surgical tubing (1 cm diameter by 60 cm length) secured using 2 mm spectra line and a brass fitting to prevent the fiberglass from fracturing. Standard measuring units are marked in 5 cm increments from the base of the elastic band along the fiberglass rod for operators to adjust the force based on target size and distance. Tissue housing cartridges are constructed for divers to carry and collect multiple samples during a single dive. These cartridges are built using sections of 25 cm PVC pipe. Vertical holes (1 cm diameter) are drilled along each PVC pipe to secure 14 Eppendorf (1.5 mL) centrifuge tubes that are used to house the tissue extraction probes with genetic samples underwater (Figure 2). Two additional horizontal holes (0.5 cm diameter) are drilled on each end of the PVC cartridges to attach elastic armbands for carrying the cartridges underwater.
How to Use:
To use the BIOPOLE, the operator places the band between her thumb and forefinger and grasps far up on fiberglass rod, then releases the rod to fire. The purpose of this design is to extract a relatively small epidermal tissue sample from a target fish while minimizing bycatch and incidental lethal and sub-lethal effects. It is designed for use in a wide variety of natural environments (e.g., kelp forests, coral reefs, streams, caves) for a wide range of target species sizes (10-100 cm). Additionally, the interchangeable tissue extraction probe design (Figure 1C) allows the operator to efficiently extract samples from dozens of individuals during a single dive.