ISSN 20751117, Russian Journal of Biological Invasions, 2012, Vol. 3, No. 1, pp. 11–15. © Pleiades Publishing, Ltd., 2012. Original Russian Text © I.V. Kartavtseva, M.P. Tiunov, A.S. Lapin, N.P. Visotchina, A.V. Ryabkova, 2011, published in Rossiiskii Zhurnal Biologicheskikh Invasii, 2011, No. 4, pp. 17–24. Invasion of Microtus rossiaemeridionalis into the Territory of the Russian Far East I. V. Kartavtsevaa, M. P. Tiunova, A. S. Lapinb,c, N. P. Visotchinac, and A. V. Ryabkovac a Institute of Biology and Soil Science, Far East Branch, Russian Academy of Sciences, Vladivostok, 690022 Russia email: [email protected] b Far Eastern State University of Humanities, Khabarovsk, 680000 Russia c Khabarovsk Antiplague Station, Khabarovsk, 680031 Russia Received April 19, 2011 Abstract—In this study, we report the first case of observation of the East European vole Microtus rossiaeme ridionalis Ognev, 1924 in the south of the Russian Far East, Khabarovsk krai, in urbanized biotopes in the vicinity of the city of Sovetskaya Gavan and two adjacent rural settlements. The species was identified by kary ological characteristics—2n = 54, NF = 56, Cbanding—and morphological characteristics—body, cra nium, baculum, and spermatozoa. DOI: 10.1134/S2075111712010031 Keywords: East European voles, Microtus rossiaemeridionalis, invasion. INTRODUCTION the vicinity of two adjacent rural settlements in the south of Khabarovsk krai in the Russian Far East (Fig. 1). The In 2009 and 2010 in the city of Sovetskaya Gavan capture sites were located close to residential build and its vicinity, small gray voles belonging to the genus ings. The capture sites, biotope descriptions, and the Microtus Shrank, 1798 were trapped. This genus was number of captured voles are given below. previously considered to be represented by only an iso lated population of M. maximowiczii voles in that hab 1. Lososin rural settlement, coast of Bukhta itat (Kostenko, 2000). However, the captured voles Lososin (49°0′24.30″N, 140°19′3.00″E), forb differed in physical appearance from the vole species meadow at the bank of the Lososin Creek that was pre that occur in the south of the Russian Far East and viously cleared away for garage construction. About Northeast China. They were not identified as a species 50 m from it on one bank, there is a mooring; on the whose range was relatively close to Sovetskaya Gavan, other bank, there are garages and storage structures. which is situated on the coast of the Tatar Channel. The meadow is intersected by a path. The vegetation is The voles were neither the Maximovicz vole nor the dominated by gramineous plants, nosebleed, worm Far Eastern vole M. fortis, whose nearest habitat is the wood, and clover, n = 7. Amur River valley, nor the Sakhalin vole M. sachalin 2. Outskirts of Lososin rural settlement ensis, which inhabits Sakhalin Island. Judging by pre (48°59′22.50″N, 140°17′49.50″E), a grassshrub fal liminary analysis of the physical appearance and low land around abandoned sanitary warehouses is odontologic properties, these voles are the most 10 m away from the highway that leads to the Lososin closely related to the Microtus arvalis group, whose rural settlement. There are residential buildings and primary range is restricted to the European part of the summer cottages intermingled with forest stands of continent. With allowance for this fact as well as the birches, aspens, and larches. This biotope occurred in difficulty in identifying the species of the captured relation to construction of warehouses and the high voles from the genus Microtus owing to poor morpho way in the past. After the warehouses were dismantled, logical differentiation, it was necessary to conduct a this area was occasionally used as a dumping site. The complex taxonomic study using morphological vegetation is dominated by gramineous plants, worm description and karyotyping that are reliably used to wood, thistle, nosebleed, and clover. The prevailing identify species of this genus. shrub is dogrose, n = 11. 3. Sovetskaya Gavan city, a wild grass land within ′ ″ ′ ″ MATERIALS Bunker port (48°58 37.94 N, 140°13 15.90 E); among all biotope studies, this one was the most In 2009 and 2010, a total of 38 voles were captured urbanized and closest to the city (it is 0.8 km from the in the vicinity of the city of Sovetskaya Gavan and in city in a straight line). Ten meters away is a gatehouse; 11 12 KARTAVTSEVA et al. a a T t y h a a k n t u r a e r B v C Se h a y a a n nay B n pad e Za n hta a 1 l Buk v a 8 G a Mayskii rural y a Lososin settlement k ts e rural settlement v o S 2 hta ya uk dna B apa 3 oZ Yug Sovetskaya ta kh e Gavan u gg B E 4 Capture B sites 7 6 olsha Oko ya Bolshaya cha R Egge River iver 2 km Malaya Egge River 5 Fig. 1. The range of Microtus rossiaemeridionalis Ognev, 1924 (according to Shenbrot and Krasnov, 2005) and capture sites in the Russian Far East: (1) Lososin rural settlement; (2) outskirts of Lososin rural settlement; (3) Sovetskaya Gavan city, Bunker port territory; (4) Bolshaya Okocha River; (5) Malaya Egge River; (6) left bank of lower reaches of the Bolshaya Egge River; (7) bank of Bukhta Egge; (8) northeast outskirts of Mayskii rural settlement. 20 m away and farther, there are other frequently vis be a garden. There are torndown military barracks ited buildings. Edificators are sedge grasses, worm close by, which currently serve as dumping sites. About wood, and reeds, n = 3. 200–300 m away from the biotope, there are wood res 4. A forb meadow close to the Bolshaya Okocha idential buildings and grazing areas. The vegetation is River (48°57′15.40″N, 140°18′9.50″E) is located dominated by gramineous plants, nosebleed, clover, opposite to abandoned summer cottages and garages wormwood, and thistle, n = 3. and close to wood residential buildings of the Okocha 8. A forb meadow in the vicinity of the Mayskii rural settlement. The biotope replaced a forest logged rural settlement is a hay field (49°0′6.90″N, for construction. This forest is currently borders on the 140°13′41.20″E). Opposite to it, there is a fallow land biotope. The meadow and adjacent areas are grazed. and abandoned gardens across the road. The biotope is The vegetation is dominated by sedge grasses, gramin surrounded by a coniferous smallleaved forest and eous plants, and clover, n = 3. dissected by three large furrows. Residential buildings 5. 48°56′36.20″N, 140°17′5.20″E. A fallow land are located 100–200 away from this site. The vegeta near the Malaya Egge River, which used to be a garden tion is dominated by gramineous plants, thistle, clover, and is close to the railroad tracks and a forest road. It and sedge grasses, n = 1. is surrounded by channels, willow stands, and mixed forest. The vegetation is represented by sedge grasses, METHODS reed, clover, nosebleed, and wormwood, n = 9. Standard morphological characteristics were stud 6. A forb meadow in the lower reach of the left bank ᭺᭺ of the Bolshaya Egge River (48°56′50.60″N, ied in 25 adult and immature individuals (12+ + , ′ ″ 140°15 31.50 E) formed as a consequence of incom 13᭺ ᭺ ): L = body length, C = tail length, Au = ear plete construction. On one side opposite to it, there length, Pl = foot length. The morphology of the first are halfconstructed garages, a wood residential build 3 ing, and forest; on the other side, there are railroad (M1) lower and third upper (M ) cheek teeth were and road bridges and fishing and recreation sites. The studied in 22 individuals. ᭺᭺ meadow is crossed by footpaths and overgrown Five voles (3+ + and 2᭺ ᭺ ) were karyotyped by unpaved back roads. The edificators are gramineous light microscopy using bone marrow cells of the plants, sedge grasses, nosebleed, and clover. Some astragalus as described in Ford and Hamerton (Ford places have dog rose, n = 1. and Hamerton, 1956). Subcutaneous administration 7. A fallow land within the littoral area of the of baker’s yeast solution was employed to stimulate Bukhta Egge (48°57′5.50″N, 140°14′34.40″E) used to mitotic division 24 h before sacrifice (0.5 mL per 25 g RUSSIAN JOURNAL OF BIOLOGICAL INVASIONS Vol. 3 No. 1 2012 INVASION OF Microtus rossiaemeridionalis INTO THE TERRITORY 13 of animal weight) (Lee and Elder, 1980). Thirty min utes before sacrifice, the animals received a colchicine solution intraperitoneally (Merck, 1 mL of 0.04% solution per 100 g of animal weight). The bone marrow from the astragalus was washed into a centrifuge tube using a syringe with a hypotonic solution (0.56% potassium chloride) and incubated at room tempera ture for 20–25 min. After hypotony, the cells were fixed by a solution of 96% ethanol and glacial acetic acid (3 : 1). Preparations were pipetted onto cooled pre moisterized slides. Dried preparations were stained with acetoorseine or 2% azure eosin (Giemsa stain, Merck, Germany). Cband staining of chromosome prepara tions was done as described in Sumner (Sumner, 1972). µ For two individuals, chromosome suspensions were 5 m prepared using a shortterm culture of bone marrow cells (Grafodatskii and Radzhabili, 1988). Fig. 2. Micrograph of a sperm of the East Asian vole in the vicinity of Sovetskaya Gavan. Stained chromosome preparations were examined using an Axioplan2 imaging microscope (Zeiss, Ger (a) (b) many). Micrographs were captured and processed by a Metasystems digital camera and software (Carl Zeiss MicroImaging GmbH, Germany).