The Alligator Gar Fish

            Alligator gar Atractosteus spatula is the largest freshwater fish in Texas and one of the largest species in North America, yet has received little attention from anglers or fisheries managers. Although gars (family Lepisosteidae) have long been considered a threat to sport fishes in the United States (summarized by Scarnecchia 1992), attitudes are changing. Recreational fisheries for alligator gar are increasing, and anglers from around the world now travel to Texas for the opportunity to catch a trophy. Because little data exist, it is unknown how current exploitation is affecting size structure and abundance of alligator gar in Texas. In many areas, alligator gar populations are declining (Robinson and Buchanan 1988; Etnier and Starnes 1993; Pflieger 1997; Ferrara 2001). Concerns by biologists and anglers about alligator gar populations in Texas have led the Texas Parks and Wildlife Department (TPWD) to consider management options for this species. In addition to this review, the TPWD has recently initiated several studies to learn more about Texas alligator gar populations. The purposes of this document are to 1) summarize alligator gar life history and ecology, 2) assess alligator gar status and management activities throughout their range, and 3) make recommendations for future alligator gar management in Texas.

          Life History In the United States, alligator gar spawn from April through June (Etnier and Starnes 1993; Ferrara 2001), coinciding with seasonal flooding of bottomland swamps (Suttkus 1963). Documented reports of alligator gar spawning are limited, though it is thought to occur in flooded backwater areas (Mendoza Alfaro et al. 2008). Spawning was recently observed in a shallow, vegetated-backwater area of Lake Texoma, Oklahoma. Snedden et al. (1999) found that lateral spawning migrations of spotted gar Lepisosteus oculatus onto floodplain areas were correlated with increased river stage and increased temperature. Because spawning is likely 2 linked to seasonal flooding, successful recruitment may be infrequent. Fecundity of alligator gar is highly variable, with means of 157,000 eggs per female and 4.1 eggs/g body weight (Ferrara 2001).

           Juvenile alligator gar likely remain in backwater spawning areas as they develop. Sakaris et al. (2003) reported that tagged juvenile alligator gar demonstrated strong site fidelity to protected backwater areas and remained near their site of capture (thought to be a spawning area), whereas adults were more mobile. Robertson et al. (2008) also captured juvenile alligator gar from backwater oxbow habitats, whereas adults were collected in the river channel. Ferrara (2001) hypothesized that juvenile alligator gar utilize shallow embayments and tributaries, and suggested that identification and protection of such nursery areas may be critical to the recovery of alligator gar populations in areas with limited nursery habitats.