Previously considered to encompass the Broad-headed Map Turtles inhabiting the Pascagoula and Pearl river systems, Graptemys gibbonsi was reduced in scope when the Pearl River form was described as a separate species, G. pearlensis Ennen, Lovich, Kreiser, Selman & Qualls, 2010.

Available information indicates that the population of Graptemys gibbonsi has apparently declined by >50% since 1950, a time period representing ca three generation lengths (75 years), meeting the criteria for an assessment of Endangered (EN A2bce). While the worst impacts from pollution and habitat destruction have apparently become less severe, habitat quality has not been restored to optimal conditions, while impacts from hurricane aftermath continue to be of concern and estimation of ongoing threats suggest that the species also meets criteria for EN A4ce ongoing over the past two generations (50 years) and the next one generation (25 years). The sympatric G. flavimaculata is currently listed as Vulnerable, while population declines of G. gibbonsi have been more severe. Thus G. gibbonsi qualifies as Endangered A2bce+4ce. Graptemys gibbonsi was previously evaluated as EN in 2011 (van Dijk 2011).

Graptemys gibbonsi is endemic to the Pascagoula River system of Mississippi, USA (Ennen et al. 2010, Lindeman 2013, TTWG 2021), although it might occur very peripherally in western Alabama. Its total range comprises about 760 km of linear rivers: Pascagoula = 130 km, Leaf = 290 km, Chickasawhay = 340 km. The estimated historical indigenous range (area of occupancy, AOO) was 15,023 sq. km, and its estimated historical indigenous extent of occurrence (EOO) was 24,225 sq. km (TTWG in press). The estimated range based on linear river km is about 1,520 sq. km (2 km per linear river km), and the estimated current AOO is about 500 sq. km.

Basking survey data from the entire Pascagoula drainage basin including tributaries (collected 2006–2018) were used to estimate the global population of Graptemys gibbonsi at ca 34,000 adult individuals (Lindeman et al. 2020). Populations are relatively continuous along river reaches, as long stretches without any G. gibbonsi are not known to occur. Density on the middle Leaf River was estimated at 34 G. gibbonsi/river km in 2007 and 44 G. gibbonsi/rkm in 2008, using mark-resight methods (Selman and Qualls 2009).

The Pascagoula Map Turtle, Graptemys gibbonsi, inhabits the large streams and the deeper medium-width tributaries of the Pascagoula River system. Females reach 29.5 cm midline straightline carapace length (SCL) and 3.7 kg, while males reach only 14.1 cm midline SCL and 340 g (Lovich et al. 2009, Selman and Lindeman 2015; P.V. Lindeman, unpubl. data). Hatchlings are 33–40 mm in midline SCL (P.V. Lindeman, unpubl. data). Clutch size ranges from 5 to 14 eggs (mean 7.5; McCoy et al. 2019). Females mature at ca 19.0 cm SCL and 11 years of age (McCoy et al. 2019). Females produce eggs annually, with up to three clutches in a year between May and August (McCoy et al. 2019), thus mean annual fecundity is 22.5 eggs, assuming three clutches of the mean clutch size, with the most productive females potentially laying over 30 eggs in a year. Longevity for the species is unknown. Generation length is unlikely to be shorter than 25 years. Females have hypertrophied jaws and jaw musculature and consume bivalve molluscs almost exclusively, in particular invasive Asian clams (Corbicula spp.), which invaded the Pascagoula River drainage in the 1960s (Lindeman 2000, Selman and Lindeman 2015, McCoy et al. 2020, Vučenović and Lindeman 2021). Males, which are more moderately broad-headed and much smaller in body size, consume far less in the way of molluscs, subsisting primarily on aquatic insect larvae, in particular trichopteran (caddisfly) larvae.

Besides collection for the pet trade, Graptemys gibbonsi is also threatened by various forms of river degradation (sedimentation, channelization, and de-snagging channels) that lead to declines in their preferred molluscan prey and the availability of basking and nesting sites (Lindeman 1998, 1999; Lovich et al. 2009). Wanton killing of turtles captured by anglers and shooting by individuals who use turtles for target practice also contribute to declines (Lovich et al. 2009). Riverine pollution was particularly significant in parts of the Pascagoula River system, including the Leaf River, as a result of riverside paper industries, municipal run-off, and riverine gravel mining (review in Lovich et al. 2009), and while pollution levels have improved, they remain of concern. In addition, the river has suffered significant impact from hurricanes in recent years.

Graptemys gibbonsi has been subjected to collection for the national and international pet trade.

Graptemys gibbonsi was recommended (Lindeman et al. 2020) and then proposed in November 2021 for federal listing as Threatened by Similarity of Appearance, for its resemblance to its sister species, G. pearlensis (USFWS 2021). It was added to CITES Appendix III in 2006 and moved to Appendix II in 2022. The Cincinnati Zoo collected several juvenile G. gibbonsi in 2018 to begin a captive assurance colony.

The primary research need is an analysis of the prey base of G. gibbonsi and how its abundance correlates with that of the species throughout the Pascagoula River drainage, as well as how prey abundance is influenced by various forms of river degradation. Nesting by G. gibbonsi has been little studied and similar analysis is needed for how nesting habitat availability correlates with abundance and population structure and how human actions impact nesting habitat.