|Scientific Name:||Graptemys flavimaculata|
|Species Authority:||Cagle, 1954|
|Red List Category & Criteria:||Vulnerable A2bce+4ce ver 3.1|
|Assessor/s:||van Dijk, P.P.|
|Reviewer/s:||Horne, B.D., Mittermeier, R.A., Philippen, H.-D., Quinn, H.R., Rhodin, A.G.J. & Shaffer, H.B.|
Graptemys flavimaculata has been of long-term concern due to declining populations, having declined historically in the Chickasawhay River and in the Leaf and upper Pascagoula rivers more recently, which together represent 80% of the range of the species; further population declines were observed following the impacts of hurricanes Ivan in 2004 and Katrina in 2005. Generation time is unknown but at age of first maturity over eight years and low rate of reproductive output, is probably more than 20 years.
Graptemys flavimaculata certainly qualifies as Vulnerable A2bce+4ce, and arguably as Endangered. It was listed as EN in 1996 Red List (criteria 2.3).
Graptemys flavimaculata is confined to the Pascagoula River system, including the Leaf, Chickasawhay, and Escatawpa rivers, in southern Mississippi. The Leaf and Chickasawhay Rivers merge to form the Pascagoula; the Escatawpa is a tributary which joins the lower Pascagoula just before its estuary (USFWS 1993). The total range comprises less than 760 km of river [Pascagoula = 130 km, Leaf = 290 km, Chickasawhay = 340 km, but not all of this area is occupied: see the 'Population' section].
Native:United States (Mississippi)
|Range Map:||Click here to open the map viewer and explore range.|
Available information indicates that the Yellow Blotched Sawback declined substantially in the late 20th century, and while the decline appears to have been halted, the species has not recovered to historical levels yet.
At the time of its description, Cagle (1954) reported G. flavimaculata to be the dominant turtle in the Pascagoula and Chickasawhay rivers. Early surveys (McCoy and Vogt 1980, in USFWS 1993) reported good populations throughout most of the Leaf and Pascagoula rivers, while populations in the Chickasawhay were in decline.
Lovich (in Ernst and Lovich 2009) found the species common in the Leaf River upstream from a pulp processing plant but absent for an undetermined distance downstream. No G. flavimaculata were observed in the upper Leaf River by Lindeman (1998) during repeated surveys during 1994–95, though he reported low to good numbers near Hattiesburg and further downstream (Lindeman pers. comm.). Some observations were made on the far upper Leaf by Selman, and the population in the middle Leaf river appeared relatively common during studies and casual observations during 2006–2010 (Selman unpubl. 2010, P.P. van Dijk pers. obs. 2010).
USFWS surveys in 1989 (Stewart 1989, Murrah 1991 in USFWS 1993) documented near-absence of the species from the Leaf and upper Pascagoula river sections where the species was abundant a decade earlier, but an apparent increase in population density in the lower Pascagoula. This subpopulation however declined substantially following the impact and aftermath of hurricane Katrina in late 2005 (Selman and Qualls 2007).
|Habitat and Ecology:||
Graptemys flavimaculata is exclusively riverine and inhabits mainly sunny river sections with moderate to strong current, abundant sand bars, and abundant deadwood basking sites.
Males and juveniles feed predominantly on insects and freshwater sponge fragments, while females consume mainly molluscs and sponges (Seigel and Brauman 1994 in Ernst and Lovich 2009).
Females may reach up to 19 cm carapace length (CL) at an average weight of 1.13 kg; males grow up to 11 cm CL at an average of 154 g weight. Females reach maturity at about 15 cm CL (Cagle 1954, Horne et al. 2003) at an estimated age of 8–10 years, while males were estimated to mature at 3–4 years (USFWS 1993). Mature females produce clutches averaging 4.7 eggs (range 3–9), and few females (16%) produce a second clutch in a year, while apparently many females skip reproduction for one or more years (Horne et al. 2003); in captivity, reproductive output is significantly higher, with females averaging 3.3 clutches of 3.4 eggs annually (Goode 1997). Generation time is unknown but at (female) age of first maturity over eight years, and exceptionally low rate of reproductive output, is probably more than 20 years.
Graptemys flavimaculata has been documented and hypothesized as impacted by a variety of processes, of which habitat degradation and pollution stand out.
Navigation and flood control improvement measures lead to the removal of snags, logs and other obstacles, which represent prime basking sites as well as invertebrate prey habitat. Localized riverine gravel mining increases river water turbidity downstream and affects invertebrate prey populations. Reservoir construction and operation within the Pascagoula basin changes river characteristics to impoundments and affects flow patterns and water quality parameters downstream.
Pollution from municipal run-off and sewage discharges, industrial effluents (particularly from paper pulp processing, and brine discharges from oilfields) and elevated dioxin levels are extensive throughout the basin and have apparently impacted the turtles directly and indirectly through compromised reproduction.
Past commercial and current personal collection for pets, wanton shooting of basking turtles, exceptionally high (increased) nest predation, at the order of 90%, by (subsidized) fish crows, raccoons and fire ants, and reduced reproductive success as a result of human disturbance of preferred nesting sites, have all been indicated as significant additional impacts on populations.
For detailed reviews of threats, see USFWS (1993), Horne et al. (2003), and Ernst and Lovich (2009).
Graptemys flavimaculata was listed as federally threatened under the Endangered Species Act (ESA) in 1991; as Endangered by the State of Mississippi; and was included in CITES Appendix III (United States) on 14 June 2006. The 1993 Recovery Plan listed six actions needed:
Horne et al. (2003) called for improved law enforcement protecting adult turtles, public education, and possibly nesting beach protection.
|Citation:||van Dijk, P.P. 2011. Graptemys flavimaculata. In: IUCN 2013. IUCN Red List of Threatened Species. Version 2013.2. <www.iucnredlist.org>. Downloaded on 13 December 2013.|
|Feedback:||If you see any errors or have any questions or suggestions on what is shown on this page, please fill in the feedback form so that we can correct or extend the information provided|