Home range and multiscale habitat selection of threatened thin-spined porcupine in the Brazilian Atlantic Forest

Abstract

The threatened and poorly known thin-spined porcupine (Chaetomys subspinosus) is endemic to the highly deforested central portion of the Atlantic Forest of eastern Brazil. In southern Bahia, anecdotal observations suggested that native forest and shade cacao (Theobroma cacao) plantations are important habitats for this species. However, no studies have examined habitat preferences. We estimated the home-range size and determined the factors influencing habitat selection at landscape, home range, and tree scales in the cacao-growing region of southern Bahia. Radiotelemetry data from 21 individuals followed for 3-25 months from April 2005 to November 2013 showed a relatively small home range (0.5-9.5 ha using minimum convex polygon methods), with males showing larger home ranges than females. Habitat selection was congruent across spatial scales, with preference for structurally complex environments at all scales. The tagged porcupines preferred trees that were large, harboring many lianas, and closer to forest limits. Tree selection was specific for each animal activity. On landscape and home-range scales, they preferred secondary forest and avoided structurally simplified, highly disturbed vegetation types such as shade cacao and rubber plantations, early secondary forest, and open areas. All these man-modified habitats were rarely used, if at all, which considerably reduces the suitable habitat within the core distribution area and profoundly impacts conservation. O ouriço-preto Chaetomys subspinosus é uma espécie endêmica e pouco conhecida da porção central da Mata Atlântica, leste do Brasil, hoje altamente desmatada. No sul da Bahia, observações anedóticas sugerem que florestas nativas e plantações sombreadas de cacau (Theobroma cacao) são importantes habitats para esta espécie. Não existe estudo, entretanto, sobre as preferências de habitat desta espécie. Nós estimamos o tamanho da área de vida e determinamos os fatores que influenciam a seleção de habitat pelo ouriço-preto em nível de paisagem, área de vida e árvore na região cacaueira do sul da Bahia. Nós analisamos dados obtidos por radiotelemetria de 21 indivíduos seguidos durante três a 25 meses de Abril 2005 a Novembro 2013. Os animais apresentaram relativamente pequena área de vida (0,5 a 9,5 ha, usando o método mínimo polígono convexo) com machos apresentando maior tamanho de área de vida do que fêmea. A seleção do habitat foi congruente através das escalas espaciais, com preferência para ambientes estruturalmente complexos em todas as escalas. Em nível de árvore, os ouriços marcados preferiram grandes árvores, árvores com muitas lianas e árvores mais próximas aos limites do fragmento florestal. A seleção de árvores foi específica para cada atividade animal e nós oferecemos detalhes. Para ambas as escalas, paisagem e área de vida, eles preferiram florestas secundárias avançadas, enquanto evitaram ou não preferiram tipos de vegetação simplificados e altamente alterados tais como plantações sombreados de cacau e seringas, florestas secundárias iniciais ...

Population and distribution of Sunda porcupine (Hystrix javanica F. Cuvier, 1823) in designated area of Cisokan Hydropower, West Java, Indonesia

“…This type of shrub/huma/talun has similar plant composition, namely kaso (Saccharum spontaneum), kirinyuh (Chromolaena odorata), kaliandra (Calliandra calothyrsus), and kiseureuh (Piper aduncum). Porcupine in eastern Brazil also prefers secondary forest and avoids structurally simplified and highly disturbed vegetation types, early secondary forest, and open areas (Giné et al 2015) Locations with natural forest land cover types are only found in half part of the Curug Japarana location. Natural forest in the location of Curug Japarana has less varied vegetation composition such as kiara karet (Ficus sp.…”

Combining species distribution modeling and field surveys to reappraise the geographic distribution and conservation status of the threatened thin-spined porcupine (Chaetomys subspinosus)

“…Comparatively, the sympatric Bahia porcupine, Coendou insidiosus , was detected in 89.5% of the sampling locations during our field effort and 87% of the locations investigated in the 1980s [ 16 ], suggesting that Chaetomys subspinosus is rarer or absent in localities where Coendou insidiosus persists. It is possible that the thin-spined porcupine to remain unnoticed and more secretive because they are less adaptable to human habitat [ 21 , 26 , 50 ]. However, we conducted the interviews preferentially with residents integrated with local wildlife and forest remnants, which were locally identified as being the most knowledgeable regarding the wildlife in each area, in order to minimize omission errors, i.e., the chances of the species being present and not being reported.…”

“…These results reinforce the idea that Chaetomys subspinosus is most eurytopic and forest-dependent than Coendou insidiosus . Even with biological features that indicate a high capacity of persistence in small fragments, such as small home ranges [ 33 , 50 ] and diet based on leaves of the abundant pioneer trees [ 20 ], the landscape scale habitat loss has apparently affected the populations of the thin-spined porcupine. Due to its dependence on native forests [ 50 ], deforestation and threats associated must result in a demographic decline.…”

“…We estimated that 8.5% of all existing forest in the current species range is included within 20 federal and state protected areas and we confirmed the species presence in seven of these reserves, which include 3.8% of all remaining forest. Thus, the conservation scenario of the thin-spined porcupine is not altogether pessimistic, considering the low spatial requirement of each individual (mean home range size of ~ 2 ha) [ 33 , 50 , 66 ]. However, to date, there is no knowledge about population data such as occupancy pattern, population density, growth rates, spatial organization, and dispersal ability.…”

“…Based on the current map available for the forest cover remnants of the Atlantic forest from Fundação SOS Mata Atlântica [ 49 ], we estimated the total area of the suitable forest included in the species range. We assumed that native forest and arboreal restinga (Brazilian sandbank forest vegetation) included in its distribution are the unique suitable habitats for the focal species, as suggested in the current literature [ 25 , 50 ]. Also, we classified and quantified the forested habitats according to three vegetation types defined by digital Brazilian Vegetation Map [ 51 ]: dense rainforest or evergreen ombrophilous forest; restinga ; and seasonal forest (deciduous and semi-deciduous forest).…”