Tagged tuna graphic by Nancy Hulbirt, SOEST Illustration.

PFRP Biology Projects

Biotelemetry Tag Retention in Pelagic Tunas

Progress Reports: FY 2012, FY 2011

Project Background and Justification

Increasing importance has been placed on understanding the movements and habitat preferences of large apex pelagic fishes such as tuna and to incorporate this data into stock assessments (Bigelow et al. 2002). Previous estimates suggest that heavily exploited populations of large pelagic species have been reduced to 10% of their carrying capacity (Ransom and Myers 2003). More recent studies, however, have shown that these numbers may not reflect the state of large pelagics due to IUU fishing (illegal, unreported, unregulated) (Sibert et al. 2006; Kleiber and Maunder 2008; Worm et al. 2009). For appropriate fisheries management and conservation plans to be promulgated, life-history characteristics, habitat preferences, and mortality estimates of large pelagics are needed. Ecological information from these parameters can be collected with the use of biotelemetry transmitters (e.g., ARGOS-linked satellite tags) that collect data over space and time.

To date many varieties of tags are available for use in fishery biology but pop-up satellite archival tags (PSATs) are increasingly becoming popular because they are fishery independent and therefore do not need to be physically recovered (i.e. archived data are downloaded using the Advanced Research & Global Observation Satellite (ARGOS) system of geosynchronous satellites). PSATs can also save themselves before being crushed at depth or if they become shed with several “fail-safe” options that optimize reporting and data return. Despite the widespread adoption of PSATs in marine studies, concerns remain about reporting rates, length of retention, and data return (Arnold & Dewar 2001). The vast majority of PSATs are shed before their programmed pop-up date (Arnold & Dewar 2001; Gunn & Block 2001) but factors influencing retention time are not well understood, nor are the factors that affect overall performance and reliability. Several authors have commented that studies addressing these issues are clearly warranted (Arnold & Dewar 2001; Gunn & Block 2001). For PSATs to be an effective tool they need to stay attached to the animal in order to monitor long-term trends and to maximise experimental design. In terms of cost:benefit, experimental designs need to be optimized to justify costs of the tags (~$3.5–4.2K USD) and ship time (e.g. operating cost of National Oceanic Atmospheric Administration (NOAA) research vessels approach $15K USD per day).

In pelagic fish, PSATs are usually attached by inserting a tag-head into the base of the dorsal fin between the pterygiophores in order to achieve maximal “mechanical” resistance. The tag-head and PSAT are joined by a tether that can be made of monofilament, fluorocarbon, stainless steel or other types of material. Tag-heads can be made of surgical grade nylon, titanium, stainless steel, and fashioned into darts, umbrellas or spear heads. Probably one of the most common routes for tag shedding is through continual movement of the tag-head in the flesh which inflames the surrounding tissue thereby providing a site of secondary infection. When towed by a fish, the forces of lift and drag on PSATs are maximized at the anchor point (i.e. tag-head) and several authors indicated drag, vibration/movement of tether/tag-head prevent tag-insertion wounds from healing, thereby creating opportunity for infection, inflamed tissue, necrosis and eventual tag shedding (Prince et al. 2002; Thorsteinsson 2002; Jellyman & Tsukamoto 2002; De Metrio et al. 2004; Grusha & Patterson 2005; Wilson et al. 2005).

We propose to study drag, lift and moments on PSAT tags in relation to the fish body as well as directly at the tag-head (point of insertion) and make recommendations on which combination of tag-head and tether promote optimal retention. By lessening the drag of PSATs tag retention may be increased through modifications of PSAT shape and tether. To reduce forces at the tag-head, a swivel can be placed halfway along the tether to reduce torque and precession (Fredriksson et al. 2007). Much more research on optimal tether and tag-head design incorporating devices to reduce torque and precession, however, need to be investigated. Such as tether designs incorporating a piston-type “shock absorber” with a universal joint which could reduce vitiating forces during locomotion. The ultimate goal is to keep the tag and tag-head as stationary as possible.

In this proposed study we will use a large boundary layer wind tunnel and water flume to measure i) the drag and drag coefficient of pelagic predatory fishes with and without PSATs, ii) we will measure the variation and maximum forces realized at the tag-head do to jerking/wobbling/spinning of the tag on its tether and iii) we will investigate the physical design of the PSATs and placement on the body in order to determine the best hydrodynamic (least drag) telemetry system and hopefully improve upon retention time and data interpretation. We choose to initiate this study using bigeye tuna as a model pelagic species. Bigeye tuna exhibit some of the poorest PSAT retention rates (median = 9 days, range from 1 to 36 days) and in general, retention of PSATs affixed on pelagic fishes could not be improved whether animals were tagged restrained on deck or tagged in the water (Musyl et al., in prep). Furthermore, this species uses special thunniform locomotion that involves efficient movements of only their tail sections, rather than the full-body undulations (Dewar and Graham 1994; Shadwick et al. 1999; Shadwick 2005; Shadwick and Syme 2008).

Objectives

Expected Outcomes

PFRP and NOAA are increasingly looking to data from PSAT tagging studies to input into stock assessment analysis. Typically PSAT tag retention is less than 30 days for most large pelagic fish species. The expected outcome of this project is to increase tag retention in Bigeye tuna by studying the drag effects of PSAT tags and measuring the induced drag at the tag/fish-body insertion point. By modifying tag design and tethers, to reduce the drag of the PSAT tag, retention times can be largely improved.

Funding for this project to be available late 2010.

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References

Arnold G, Dewar H (2001) Electronic tags in marine fisheries research: a 30-year perspective. In: Sibert JR, Nielsen JL (eds) Electronic tagging and tracking in marine fisheries reviews: methods and technologies in fish biology and fisheries. Kluwer Academic Press, Dordrecht, p 7-64.

Bigelow KA, Hampton J, Miyabe N (2002) Application of a habitat-based model to estimate effective longline fishing effort and relative abundance of Pacific bigeye tuna (Thunnus obesus). Fisheries Oceanography 11(3):143-155.

De Metrio GD, Oray I, Arnold GP, Lutcavage M, Deflorio M, Cort JL, Karakulak S, Anubar N, Ultanur M (2004) Joint Turkish-Italian research in the eastern Mediterranean: bluefin tuna tagging with pop-up satellite tags. Collect Vol Sci Pap ICCAT 56:1163-1168.

Dewar H, Graham JB (1994) Studies of tropical tuna swimming performance in a large water tunnel. I. Energetics. J. Exp. Biol. 192,13-31.

Fredriksson D, Reichel J, Waters R, Fragoso N, Lutcavage M (2007) A hydrodynamic analysis of popup satellite archival tags used for tracking marine species. Second International Symposium on Tagging and Tracking Marine Fish with Electronic Devices, October 8-11, 2007, Donostia-San Sebastián, Spain (abstract).

Grusha DS, Patterson MR (2005) Quantification of drag and lift imposed by pop-up satellite archival tags and estimation of the metabolic cost to cownose rays (Rhinoptera bonasus). Fish Bull 103:63-70.

Gunn J, Block B (2001) Advances in acoustic, archival, and satellite tagging of tunas. In: Block BA, Stevens ED (eds) Tuna Physiology, Ecology, and Evolution. NY: Academic Press, p 167–224.

Jellyman D, Tsukamoto K (2002) First use of archival transmitters to track migrating freshwater eels Anguilla dieffenbachii at sea. Mar Ecol Prog Ser 233:207-215.

Kleiber P, Maunder MN (2008) Inherent bias in using aggregate CPUE to characterize abundance of fish species assemblages. Fisheries Research 93:140-145.

Meyers RA, Worm B (2003) Rapid worldwide depletion of predatory fish communities. Nature 423:280-283.

Prince ED, Ortiz M, Venizelos A, Rosenthal DS (2002) In-water conventional tagging techniques developed by the Cooperative Tagging Center for large, highly migratory species. In: Lucy JA, Studholme AL (eds) Catch and Release in Marine Recreational Fisheries. Am Fish Soc Symp 30:155–171.

Sibert J, Hampton J, Kleiber P, Maunder M (2006) Biomass, size, and trophic status of top predators in the pacific ocean. Science 314:1773-1776.

Shadwick RE, Katz SL, Korsmeyer KE, Knower T, Covell JW (1999) Muscle dynamics in skipjack tuna: timing of red muscle shortening in relation to activation and body curvature during steady swimming. J. Exp. Biol. 202,2139 -2150.

Shadwick RE (2005) How tunas and lamnid sharks swim: an evolutionary convergence. Am. Sci. 93,524-531.

Shadwick RE, Syme DA (2008) Thunniform swimming: muscle dynamics and mechanical power production of aerobic fibres in yellowfin tuna (Thunnus albacares) J. Exp. Biol. 211,1603-1611.

Thorsteinsson V (2002) Tagging Methods for Stock Assessment and Research in Fisheries. Report of Concerted Action FAIR CT.96.1394 (CATAG). Reykjavik Marine Research Institute Technical Report 79: p 179.

Wilson SG, Lutcavage ME, Brill RW, Genovese MP, Cooper AB, Everly AW (2005) Movements of bluefin tuna (Thunnus thynnus) in the northwestern Atlantic Ocean recorded by pop-up satellite archival tags. Mar Biol 146:409-423.

Worm B, Hilborn R, Baum JK, et al. (2009) Rebuilding Global Fisheries. Science 325:578-585.

Principal Investigators

Dr. T. Todd Jones
National Marine Fisheries Service
Pacific Isles Fisheries Science Center
Kewalo Research Facility
1125 B Ala Moana Blvd
Honolulu, Hawaii 96814
USA
Phone (808) 983-3704
FAX (808) 983-3700
email: Todd.Jones@noaa.gov

Dr. John Wang
National Marine Fisheries Service
Pacific Isles Fisheries Science Center
Kewalo Research Facility
1125 B Ala Moana Blvd
Honolulu, Hawaii 96814
USA
Phone (808) 983-3714
FAX (808) 983-3700
email: John.Wang@noaa.gov


Dr. Michael Musyl
National Marine Fisheries Service
Pacific Isles Fisheries Science Center
Kewalo Research Facility
1125 B Ala Moana Blvd
Honolulu, Hawaii 96814
USA
Phone (808) 983-3705
FAX (808) 983-3700
email: Michael.Musyl@noaa.gov

 

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