Since 2002, the Adopt-A-Billfish program has played a critical role in advancing the science and conservation of billfishes and other large pelagic species. Through this program, TBF has contributed to deployments of nearly 300 pop-up satellite archival tags (PSATs) across the Atlantic and eastern Pacific Oceans. These investments have directly enabled some of the most influential research on billfish movement, habitat use, and fishery interactions conducted to date.

Research funded by Adopt-A-Billfish and research partners has fundamentally reshaped our understanding of vertical and horizontal habitat use by species such as white marlin, blue marlin, sailfish, swordfish, and longbill spearfish. Satellite tagging revealed that these species routinely occupy deeper waters than previously assumed, frequently making excursions into mesopelagic depths and exhibiting strong diel patterns tied to light levels, temperature structure, and prey availability. These findings corrected long-standing assumptions that billfishes were primarily surface-oriented predators and demonstrated that vulnerability to fishing gear extends well below the surface.

Adopt-A-Billfish supported studies also documented ocean-scale movements and transboundary migrations, showing that billfishes regularly cross international boundaries and management jurisdictions. Tagging results demonstrated connectivity between U.S. waters and international regions of the Atlantic, Caribbean, and Gulf of America, underscoring the need for international cooperation in billfish management through organizations such as ICCAT.

Another major contribution of this work has been improved understanding of post-release survival and behavior. Several studies showed that when handled properly, most billfishes survive catch-and-release events, with satellite tags documenting recovery and return to normal depth-use patterns following release. These findings provided strong scientific support for catch-and-release practices in recreational fisheries and helped validate conservation measures already favored by anglers.

Adopt-A-Billfish funding also enabled groundbreaking research on habitat compression caused by hypoxia and oxygen minimum zones. Satellite data revealed that low-oxygen conditions can force billfishes into narrower vertical habitat layers, increasing overlap with fishing gear and potentially elevating bycatch risk. These results linked oceanographic change directly to fish behavior and fishery interactions, providing valuable insight for ecosystem-based fisheries management.

Collectively, these projects produced dozens of peer-reviewed publications, advancing our knowledge of billfish behavior, making Adopt-A-Billfish one of the most impactful conservation-driven funding programs supporting pelagic fisheries science.

In short, Adopt-A-Billfish funding has translated directly into better science, better management, and better conservation outcomes for billfishes worldwide, while strengthening the connection between anglers, scientists, and the future of these iconic species.

• Dewar, H., E.D. Prince, M.K. Musyl, R.W. Brill, C. Sepulveda,J. Luo, D. Foley, E.S. Orbesen, M.L. Domeier, N. Nasby-Lucas, D. Snodgrass, R.M. Laurs, B.A. Block, and L.M. McNaughton (2011). Movements and Behaviors of Swordfish in the Atlantic and Pacific Oceans Examined Using Pop-up Satellite Tags Fisheries Oceanography 20(3): 219-241.

• Goodyear,P., J. Lou, E.D. Prince, D. Snodgrass, E.S. Orbesen, and J. Serafy (2008). Vertical habitat use of Atlantic blue marlin Makaira nigricans: interaction with pelagic longline gear. Marine Ecology Progress Series. Vol. 365: 233-245. 

• Hoolihan, J.P., J. Luo, D.E. Richardson, D. Snodgrass, E.S. Orbesen, and E.D. Prince (2009). Vertical Movement Rate Estimates for Atlantic Istiophorid Billfishes Derived from High Resolution Pop-up Satellite Archival Data. Bulletin of Marine Science, 84(3): 257-264. 

• Hoolihan, J.P., J. Luo, F.J. Abascal, S.E. Campana, G.M. De Metrio, L. Domeier L.A. Howey, M.E. Lutcavage, M.K. Musyl, J.D. Neilson, E.S. Orbesen, E.D. Prince, and J.R. Rooker (2011). Evaluating Post-release Behaviour Modification in Large Pelagic Fishes Deployed With Pop-up Satellite Archival Tags. ICES Journal of Marine Science 68(5): 880-889.

• Hoolihan, J.P., J. Luo, D. Snodgrass, E.S. Orbesen, A.M. Barse, E.D. Prince (2015) Vertical and horizontal habitat use by white marlin Tetrapturus albidus (Poey, 1860) in the western North Atlantic Ocean. ICES Journal of Marine Science. doi: 10.1093/icesjms/fsv082.

• Hoolihan, J. P., J.G. Luo, C.P. Goodyear, E.S. Orbesen, and E.D. Prince (2011). Vertical habitat use of sailfish (Istiophorus platypterus) in the Atlantic and eastern Pacific, derived from pop-up satellite archival tag data. Fisheries Oceanography 20(3): 192-205.

• Kerstetter, D.W., E.S. Orbesen, D. Snodgrass, and E.D. Prince (2009). Movements and Habitat Utilization of Two Longbill Spearfish Tetrapturus Pfluegeri in the Eastern Tropical South Atlantic Ocean. Bulletin of Marine Science, 85(2): 173-182.

• Lerner, J.D., D.W. Kerstetter, E.D. Prince, L. Talaue-McManus, E.S. Orbesen, A.D. Mariano, Snodgrass, G.L. Thomas (2012). Swordfish vertical distribution and habitat use in relation to diel and lunar cycles in the western North Atlantic. Transactions of the American Fisheries Society 142(1): 95-104.

• Neilson, J.D., Loefer, J., Prince, E.D., Royer, F., Calmettes, B., Gaspar, P., Lopez, R. and Andrushchenko, I., 2014. Seasonal distributions and migrations of Northwest Atlantic swordfish: inferences from integration of pop-up satellite archival tagging studies. PLoS One, 9(11), p.e112736.

• Orbesen, E.S., J.P. Hoolihan, J.E. Serafy, D. Snodgrass, E. Peel, and E.D. Prince (2008). Transboundary movement of Atlantic istiophorid billfish amongst international and U.S. domestic management areas, inferred from mark-recapture studies. Marine Fisheries Review. 70(1): 14-23.

• Prince, E.D., J. Luo, C.P. Goodyear, J.P. Hoolihan, D. Snodgrass, E.S. Orbesen, J.E. Serafy, M. Ortiz, and M. Schirripa, (2010). Ocean Scale Hypoxia-Based Habitat Compression of Atlantic Istiophorid Billfishes. Fisheries Oceanography 19(6): 448-462.

• Prince, E.D., R.K. Cowen, E.S. Orbesen, S.A. Luthy, J.K. Llopiz, D.E. Richardson and J.E. Serafy (2005). Movements and spawning of white marlin (Tetraptuerus albidus) and blue marlin (Makaira nigricans) off Punta Cana, Dominican Republic. Fishery Bulletin 103:659-669.

• Prince, E.D. and Goodyear, C.P., 2007. Consequences of ocean scale hypoxia constrained habitat for tropical pelagic fishes. Gulf and Caribbean Research, 19(2), pp.17-20.

• Prince, E.D., D.B. Holts, D.G. Snodgrass, E.S. Orbesen, J. Luo, M.L. Domeier, and J.E. Serafy. (2006). Transboundary movement by sailfish (Istiophorus platypterus) off the Pacific side of Central America. Bulletin of Marine Science. 79(3): 827-838.

• Stramma, L., Prince, E.D., Schmidtko, S., Luo, J., Hoolihan, J.P., Visbeck, M., Wallace, D.W., Brandt, P. and Körtzinger, A., 2012. Expansion of oxygen minimum zones may reduce available habitat for tropical pelagic fishes. Nature Climate Change, 2(1), pp.33-37.Ocean Heat Content Reveals Secrets of Fish Migrations.