Distribution and conservation of the bamboo rat Kannabateomys amblyonyx ( Rodentia , Echimyidae ) in Minas Gerais State , Brazil

This note reports data on occurrence of the echimyid Kannabateomys amblyonyx in Minas Gerais State, southeastern Brazil. Data were obtained from consult to 26 museums, bibliography search and field sampling. We found nine municipalities with species records, eight within the Atlantic Forest biome and one in the transitional area between the Atlantic Forest and Cerrado. Habitats occupied comprised bamboo groves in Montane Stational Semidecidual Forest, Submontane Stational Semidecidual Forest and bamboo patches located in middle of open area, originally covered by Submontane Stational Semidecidual Forest. Potential impacts detected were deforestation, fires, hunting and the presence of livestock and domestic dogs.


Introduction
Kannabateomys amblyonyx is a large echimyid rodent, distributed from southeastern Brazil to southeastern Paraguay and northern Argentina.It inhabits coastal Atlantic Forest, inland rainforests and wet gallery forests, mainly in waterside bamboo groves (Emmons and Feer, 1997).It has nocturnal and arboreal habits, lives in small family groups and defends a territory through vocalization.Kannabateomys amblyonyx is a species closely associated with bamboos, feeds mainly on young shoots and nests in the middle of bamboo groves (Kierulff et al., 1991;Silva, 1993Silva, , 2005;;Stallings et al., 1994;Oliveira and Bonvicino, 2006;Silva and Vieira, 2006;Silva et al., 2008).In Brazil, records of K. amblyonyx are restricted to the southeast and southern States (from Espírito Santo to Rio Grande do Sul) of the Atlantic Forest (Oliveira and Bonvicino, 2006;Bonvicino et al., 2008).In relation to Minas Gerais, the previous authors mentioned a "probable occurrence" of the species in the eastern part of this state.The Livro Vermelho das Espécies da Fauna Ameaçada de Extinção de Minas Gerais (Red Book of Threatened Fauna of Minas Gerais), where K. amblyonyx is listed as vulnerable (Rylands, 1998), points out three localities with species occurrence in the state, based on unpublished technical reports.In all, consistent information is lacking on the localities and habitats of occurrence of this species, which distribution in Minas Gerais State is poorly known.Aiming to contribute to the knowledge on the distribution and conservation of K. amblyonyx, we present new occurrence sites and summarize the available data on the species distribution, potential threats and habitat occupancy in Minas Gerais.

Results
We identified nine municipalities with K. amblyonyx records in Minas Gerais State, eight of them in Atlantic Forest domains and one in a transitional area between Atlantic Forest and Cerrado biomes, according to IBGE (2009) (Figure 1).Types of records and available data on geographic coordinates, altitude and habitat on each locality are shown in Table 1.On 7 April 2009 at around 4 p.m., an individual was photographed by RAS (Figure 2) in a locality known as Fazenda Santa Clara (21º53'17"S, 43º10'32"W; 473m a.s.l.), municipality of Santana do Deserto, Atlantic Forest (IBGE, 2009).The individual was photographed on the ground, crossing a short paving stone (ca.20m long) between two bamboo groves located in the middle of grassland.In this same area, individuals were often sighted with nocturnal activity.This locality was originally covered by Submontane Semidecidual Stational Forest (Veloso et al., 1991), which was partially cleared over the past century for coffee cultivation and livestock.The current physiognomy is characterized by remaining fragments in a field matrix, where bamboo groves are found in the middle of open formations and in the inner and border of forest fragments.On 23 March 2007 an individual was photographed by CLA (Figure 2) in a locality known as Sapecado (21º14'12"S, 42º44'00"W; 771m a.s.l.), municipality of Cataguases, Atlantic Forest (IBGE, 2009).The individual was found around 10 p.m. in a bamboo grove in the inner of a Montane Semidecidual Stational Forest fragment (Veloso et al., 1991).This area was impacted by wood removal for timber and coal production and prescribed fires for agriculture and livestock expansion, which ended about 45 years ago.The current principal impacts include the presence of livestock and domestic dogs in the inner and outer border of fragments and predatory hunting.On 13 January 2010 an individual was donated to FAS in a locality known as Sinimbu (21º20'20"S, 42º45'45"W; 301m a.s.l.), municipality of Cataguases, Atlantic Forest (IBGE, 2009).According to the donors, the individual was active in a bamboo grove on the border of a forest fragment around 21h that same night.The specimen, a juvenile male, is deposited in the mammalian collection of Museu de Zoologia João Moojen of Universidade Federal de Viçosa, Viçosa municipality, Minas Gerais (MZUFV-CM 3328) (Figure 3).The area is characterized as a Submontane Stational Semidecidual Forest fragment (Veloso et al., 1991), which had been deforested over the past 70 years for hardwood exploitation and charcoal production.(IBGE, 2009).The two first references are based on unpublished technical reports while the third corresponds to author's personal observations.No specimen from these localities was found in the consulted collections.

Discussion
Kannabateomys amblyonyx specimens from Minas Gerais had a little representation in the consulted collections, which may be a consequence of at least two main factors.First, this may represent a sub-sampled species, with few captures and efforts applied in bamboo patches (the main habitat occupied by K. amblyonyx) as compared to other sampled vegetal formations during mammalian surveys.Added to this, once the species feeds exclusively on bamboo stems, twigs   (Veloso et al., 1991).Potential impacts observed in the area included cattle grazing and trampling and the exploitation of bamboo groves by a stick factory.Museum consults allowed the lo-and leaves (Silva, 2005), it is not captured in baited traps commonly used in small mammal sampling such as sherman and tomahawk live traps (Kierulff et al., 1991).Appropriated methods for the species record such as double entry traps installed on artificial bamboo bridges (Kierulff et al., 1991), active search and listening efforts (Olmos et al., 1993) are generally not applied in mammalian inventories.Second, this may represent a less abundant species, with isolated populations or meta-populations restricted to the forest fragments which host bamboo areas with the capacity to provide spatial and feeding resources needed for maintaining such populations.In this context, Rylands (1998) points to a possible genetic constraint due to insularization of populations, which can be even more aggravated due to the species low reproductive fitness (Silva 1993;Oliveira and Bonvicino, 2006).(Paglia et al., 2005).Gallery forests represent forest formations in the middle of Cerrado savanna (Ribeiro and Walter, 1998), and it is possible that inward from these transitional areas, the species may occur in gallery forest stretches of Cerrado biome.According to Emmons and Feer (1997), K. amblyonyx occurs in wet gallery forests and bamboo patches between fields.The possible occur-rence of K. amblyonyx in Cerrado physiognomies, however, needs to be elucidated.
It is worth noting that most of the localities with known records comprise unprotected private areas.In some of these localities (Santana do Deserto, Laranjal and Cataguases municipalities) potential impacts such as deforestation, fires, hunting and the presence of livestock and domestic dogs were detected.In order to preserve the K. amblyonyx populations and key habitat features, the establishment of private reserves in these areas is strongly recommended.In this context, it is also worth mentioning that a mammalian survey performed in the protected area of Reserva Peti (Paglia et al., 2005) did not detected the species, which was previously reported for this locality by Rylands (1998).
We have presented a first approach on the distribution of the bamboo rat Kannabateomys amblyonyx in Minas Gerais State.However, more sampling and observation effort is needed for a better understanding on biogeography and ecology of the species in the region, mainly in the limits of Atlantic Forest and adjacent Cerrado areas.

Table 1 .
Summary of records of Kannabateomys amblyonyx in Minas Gerais, southeastern Brazil (?=data not available).
Figure 1.Municipalities with records of Kannabateomys amblyonyx in Minas Gerais State.Full circles indicate the municipalities with records confirmed by collected specimen or photography of living animal while empty circles indicate the localities cited by Rylands (1998).Volume 7 number 1  january -april 2012