Balloon Tag Manufacturing Technique for Sensor Fish and Live Fish Recovery

Summary

A protocol is presented for designing and manufacturing balloon tags to recover Sensor Fish and live fish, allowing assessment of their physical condition and biological performance in hydraulic structures. The method optimizes balloon tag performance by considering factors such as balloon volume, inflation/deflation times, component selection, and the characteristics of the injected water.

Abstract

Fish may experience injuries and mortality when they pass through hydraulic conveyances at hydropower dams, even if these conveyances are designed to be fish-friendly, such as downstream bypass systems, modified spillways and turbines. The main methods used to study fish passage conditions in hydraulic structures involve direct, in situ testing using Sensor Fish technology and live fish. Sensor Fish data helps identify physical stressors and their locations in the fish passage environment, while live fish are assessed for injuries and mortality. Balloon tags, which are self-inflating balloons attached externally to Sensor Fish and live fish, aid in their recovery after passing through hydraulic structures.

This article focuses on the development of balloon tags with varying numbers of dissolvable, vegetable-based capsules containing a mixture of oxalic acid, sodium bicarbonate powders, and water at two different temperatures. Our research determined that balloon tags with three capsules, injected with 5 mL of water at 18.3 °C, consistently achieved the desired balloon volume. These tags had a mean inflation volume of 114 cm³ with a standard deviation of 1.2 cm³. Among the balloon tags injected with water at 18.3 °C, it was observed that the two-capsule balloon tags took the longest time to reach full inflation. In addition, the four-capsule balloon tags demonstrated a faster inflation start time, while the three-capsule balloon tags demonstrated a faster deflation start time. Overall, this approach proves to be effective for validating the performance of new technologies, improving turbine design, and making operational decisions to enhance fish passage conditions. It serves as a valuable tool for research and field evaluations, aiding in the refinement of both the design and operation of hydraulic structures.

Introduction

Hydropower is a significant renewable energy resource worldwide. In the United States, hydropower contributes an estimated 38% or 274 TWh of electricity generated from renewable sources¹ and has the potential to add approximately 460 TWh per year². However, as hydropower development increases, concerns about fish injury and mortality during hydraulic passage have become paramount³. Various mechanisms contribute to fish injuries during passage, including rapid decompression (barotrauma), shear stress, turbulence, strikes, cavitation, and grinding⁴. Although these injury mech....

Protocol

1. Acid/base encapsulation

1. Mix a 1:2 ratio by the weight of H₂C₂O₄ (oxalic acid) and NaHCO₃ (sodium bicarbonate) in a mixing cup (see Table of Materials). If the acid-base powder mix is crystallized, grind it down using a mortar and pestle (Figure 1A).
2. Retrieve the size 3 vegetable-based capsules and the semi-automatic capsule filling machine to begin the process (see Table of Material.......

Discussion

This study concluded that three-capsule balloon tags injected with 5 mL of water at 18.3 °C had a slower start inflation time and consistently larger volume compared to two-capsule and four-capsule balloon tags. When the balloon tags were injected with water at 12.7 °C, the average volume was smaller, and the inflation time was longer. The three-capsule begins deflating first, followed by the four-capsule, and lastly the two-capsule. The inflation and deflation periods associated with each water temperature can.......

Materials

Name	Company	Catalog Number	Comments
3D Printed Silicone Stopper Plate	NA	NA
ARC800 Sensor Fish	ATS	NA
FDM 3D printer	NA	NA
Manual Capsule Filler Machine CN-400CL (Size #3)	Capsulcn	NA
Mold Star 15 SLOW	Smooth-On	NA
Oil-Resistant Buna-N O-Ring	McMaster-Carr	SN: 9262K141
Oxalic Acid, 98%, Anhydrous Powder (C2H2O4)	Thermo Scientific	CAS: 144-62-7
Rubber Band Expansion Tool	iplusmile	NA
Separated Vegetable Cellulose Capsules (Size #3)	Capsule Connection	NA
Smiley Face YoYo Latex balloon	YoYo Balloons, Etc.	NA
Sodium Bicarbonate Powder (CHNaO3)	Sigma	CAS: 144-55-8
Spectra Fiber Braided Fishing Line (50 lbs.)	Power Pro	NA