Migrations and movements of Atlantic tarpon revealed by two decades of satellite tagging

Abstract

Understanding large‐scale migratory behaviours, local movement patterns and population connectivity are critical to determining the natural processes and anthropogenic stressors that influence population dynamics and for developing effective conservation plans. Atlantic tarpon occur over a broad geographic range in the Atlantic Ocean where they support valuable subsistence, commercial and recreational fisheries. From 2001 through 2018, we deployed 292 satellite telemetry tags on Atlantic tarpon in coastal waters off three continents to document: (a) seasonal migrations and regional population connectivity; (b) freshwater and estuarine habitat utilization; (c) spawning locations; and (d) shark predation across the south‐eastern United States, Gulf of Mexico and northern Caribbean Sea. These results showed that some mature tarpon make long seasonal migrations over thousands of kilometres crossing state and national jurisdictional borders. Others showed more local movements and habitat use. The tag data also revealed potential spawning locations consistent with those inferred in other studies from observations of early life stage tarpon leptocephalus larvae. Our analyses indicated that shark predation mortality on released tarpon is higher than previously estimated, especially at ocean passes, river mouths and inlets to bays. To date, there has been no formal stock assessment of Atlantic tarpon, and regional fishery management plans do not exist. Our findings will provide critical input to these important efforts and assist the multinational community in the development of a stock‐wide management information system to support informed decision‐making for sustaining Atlantic tarpon fisheries.

Documentation of Atlantic tarpon (Megalops atlanticus) space use and move persistence in the northern Gulf of Mexico facilitated by angler advocates

“…Regardless of the mechanism underpinning the importance of the Mississippi River Delta to tarpon, citizen scientists are clearly part of the conservation solution. Several recent advances in our understanding of tarpon population structure (Guindon et al, 2015), movement and migration (Luo et al, 2020), and nursery habitat use (Wilson, Adams, & Ahrens, 2019) have been facilitated by citizen science efforts, particularly in Florida. For example, tarpon anglers from nine southeastern US states (Texas through Virginia) collected nearly 24,000 tarpon tissue samples in support of a genetic mark-recapture study; 96% of these were collected in F I G U R E 2 (a) The move persistence parameter ( g t ) displayed as a time-series for the state-space model filtered tarpon data, with white and grey name templates indicating fish tagged in Alabama verses Louisiana, respectively.…”

“…Of particular interest is identifying when northern Gulf of Mexico tarpon begin their fall migration, and whether or not these fish return to Florida. Notably, of the nearly 300 tarpon tracks reported in Luo et al (2020), no tarpon tagged east of the Mississippi River migrated west of Louisiana, or vice-versa. Unfortunately, our tags detached before we could gain insight into these patterns.…”

Seasonal Occurrence, Horizontal Movements, and Habitat Use Patterns of Whale Sharks (Rhincodon typus) in the Gulf of Mexico

“…Coastal pelagic and highly migratory fishes tagged near the Yucatan Channel or Straits of Florida (the two immigration/emigration points for the GOM) show highly variable movements, whereas species tagged in the NC and NW GOM appear to have movements restricted to the GOM. For example, Luo et al (2020) studying movements of tarpon, Megalops atlanticus, in the GOM, reported that individuals tagged in the SE GOM near the Straits of Florida showed variable movements between the GOM and United States east coast; whereas other individuals tagged in the western GOM primarily remained in the GOM. Similarly, Hueter et al (2013) tagged 35 whale sharks in waters surrounding the Yucatan Peninsula and reported a variety of movements into the GOM, Caribbean Sea, Straits of Florida, and South Atlantic Ocean.…”

Movement patterns of juvenile Atlantic tarpon (Megalops atlanticus) in Brewers Bay, St. Thomas US Virgin Islands

“…Males reach sexual maturity at about 90 cm and females at 128 cm FL [13,[19][20][21]. Much of our knowledge of tarpon movements and behaviors come from satellite tracking and conventional anchor tag studies conducted in Florida, southeast Atlantic, Gulf of Mexico, and the northwestern Caribbean (e.g., Mexico, Belize, Cuba) [6,7,13,14,22,23]. These studies have focused on large-scale movements (>500 km) of large adult tarpon (>130 cm FL) that support a valuable sport shery.…”

“…Tracking the movements and migrations of animals in the aquatic environment provides insight into spatial and temporal patterns of habitat use, trophic interactions, reproductive behavior, and behavioral responses to environmental change [1][2][3][4][5][6][7].…”