Agenda - Parks and Recreation Commission - 01/10/2002

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BLA.NDING'S TURTLE CueSta, n ~a~:l L ~-.zn-pzwzl.-"r. (c~.:. ~ .... .. . 332 ?.nn'doidea blandingii (Hotbrook) OFFICIAL ST.a, TL'S. Threatened ©t9~8, S~ute of M/nneso~a, ¥~ra Ming Wong BASIS FOR STATUS. Although formerl~ more widespread, the Bland log's turtle is now restricted co a small number of ~tates and province's the Upper Midwest. stretching from Nebraska eastward to Michigan. On ratio, and Quebec. A smaller remnant population, spanning portion~ few New England states, as well as a number of scattered population throughout the Northeast. testify to the turtle's more expanded range earlier times. Minnesota lies on the northwest periphery of the specie, range. An extensive area of sand dunes and marshes along the Mississipp River. south of'the town of Kellogg. is recognized as a major concentratio~ area for the turde and may be one of the largest breeding populations its entire range. Elsewhere in the state, the Blanding's turtle has a mot, spotty distribution, following the Mississippi and Sc. Croix rivers north ward into east-central Minnesota and the Minnesota River westward the south-central portions of the state. Two rec~'nt records from Pipes[on, County also confirm the species' presence in the Missouri River drainag, of extreme sot:thwestem Minnesota. As a marsh inhabitant the recent destruction of wetiand habitats by drain . age and/or inundation for agricultural purposes, river channeli~.kmon, am water impoundment has greatly decreased available habitat Ibr the species Like other turtles, the Blanding's turtle is also vulnerable to collecting az a desirable pet species {S45 for a 15 to 20 centimeter turtle): it is easily letted in areas where it is abundant, especially during the nesting season The species' life history, also makes this turtle particularly susceptible human disturbances, as evidenced by a long term and intensive study o the population inhabiting the Kellogg Dunes (Pappas. personal communi cation). Some features contributing to this susceptibility are late ma[urn lion. Iow reproductive potential (one clutch/season), long-lived adults and high morality of eggs and juveni1,es. Population and reproductwe d' namics suggest viable populations of Blanding's turtles are dependent · large numbers of animals and adequate areas of undisturbed habitat. PREFERRED HABITAT: The preferred habitat of the Blanding's turth includes calm, shallow water, rich. aquatic vegetation and sandy upland~ for nesting. Studies by Congdon et al. (1983) in Michigan and by Linc} (personal communication} in Massachusetts have shown that nesting fe males may travel considerable distances (200 to 400 meters) to a nestinl area, passing enroute what appears to be suitable nesting habitat immedi. ately adjacent to the marsh in which they reside. AID TO IDENTIFICATION: Blanding's turde is medium-sized, averag lng 15 to 2.5 centimeters in length. The species' most diagnostic field char acteristics are its smooth, domed upper shell, or carapace, and its brigh yellow neck. throat, and chin. The carapace usuaily appears bluish black with numero~ s ;ge, cks of yellov( throughout. Tile lower shell, or plastron ik'bi'igi~t-½~llbw wi'd=. blii~:k"patches ~6n the outs',Td~: margin, in general. adult male can be distinguished from the female by its slightly indenter plastron and longer tail. The most distinct feature of the plastron is hinge, which allows the turde to raise the plastron upward and provid~ more protection to the soft extremities that it has pulled inside the shell For this reason the species is often referred to as a "semibox" tunic. RECOMMENDATIONS: Efforts to identify, pro~cct, and preserve pre fen'ed habitats of this species should be continued, particularly when populations are locally abundant. Additional information on the species local distribution and abundance should also be collected to allow an ac curate assessment of its current status and to aid in protection efforts. SELECTED REFERENCES: Breckenridge 1944: Conant 1975: Con. gdon et al. 1983: Ewer~ 1,982: Graham and Doyle 197'7: McCoy 1977 Vogt !.981. Blunding% Turtle: adull viewed from above tlopl and behr,~ Iho~.h~m): ~,,de view 5hDwll Iff _'51Jhouene. '29 - 7,~