First sighting record of the elusive Nilgiri Marten Martes gwatkinsii in Wayanad, Southern Western Ghats, India

This note reports the first sighting of the elusive and threatened Nilgiri marten in Wayanad district of Southern Western Ghats. All the previously known occurrences of Nilgiri marten in the Western Ghats, along with the addition of this new record, were marked on a map. This record highlights the need for further studies on this population’s status and behavior, as well as to understand whether any coexistence or conflicts occur with local people, thereby examining underlying threats to the population in the Wayanad region.

Small mammals in the human-dominated landscape in the northern Western Ghats of India

The Western Ghats biodiversity hotspot is under huge anthropogenic pressure, with unique flora and fauna facing severe threats from habitat fragmentation, loss, and degradation.  The northern Western Ghats has been poorly studied for its small mammal fauna, hence we examined small mammals near Pune from 2014 to 2017.  Live trapping was carried out in irrigated and rainfed agriculture fields, forests, and grasslands at low, mid, and high elevations.  A total of 538 individuals were trapped, representing 17 species of rodents and one shrew.  Most abundantly captured species were Millardia kondana (23%), Mus saxicola (19%), Suncus murinus (17%), and Mus booduga (13%).  Species richness and abundance of small mammals varied across the habitats.  High elevation grasslands were species-rich relative to low elevation grasslands and forests.  Our observations indicate that human disturbances play a role in determining the richness and abundance of small mammals in the area, where populations are under threat from urbanization, tourism, agriculture, grazing, and fire.  Habitat and species specific conservation measures need to be taken, coupled with in-depth species–habitat relationship studies, for the conservation of small mammal diversity of the northern Western Ghats.

A comparison of the pitfall trap, Winkler extractor and Berlese funnel for sampling ground-dwelling arthropods in tropical montane cloud forests

Little is known about the ground-dwelling arthropod diversity in tropical montane cloud forests (TMCF). Due to unique habitat conditions in TMCFs with continuously wet substrates and a waterlogged forest floor along with the innate biases of the pitfall trap, Berlese funnel and Winkler extractor are certain to make it difficult to choose the most appropriate method to sample the ground-dwelling arthropods in TMCFs. Among the three methods, the Winkler extractor was the most efficient method for quantitative data and pitfall trapping for qualitative data for most groups. Inclusion of floatation method as a complementary method along with the Winkler extractor would enable a comprehensive quantitative survey of ground-dwelling arthropods. Pitfall trapping is essential for both quantitative and qualitative sampling of Diplopoda, Opiliones, Orthoptera, and Diptera. The Winkler extractor was the best quantitative method for Psocoptera, Araneae, Isopoda, and Formicidae; and the Berlese funnel was best for Collembola and Chilopoda. For larval forms of different insect orders and the Acari, all the three methods were equally effective.

Spatial synchrony of a highly endemic fish Assemblage (Segredo Reservoir, Iguaçu River, Paraná State, Brazil)

In this study, patterns of spatial synchrony in population fluctuations (cross-correlation) of an endemic fish assemblage of a Neotropical reservoir (Segredo Reservoir, Iguaçu River, Paraná State, Brazil) were reported. First, the level of population synchrony for 20 species was estimated. Second, population synchrony was correlated, using the Mantel test, with geographical distances among sites (n = 11) and also environmental synchrony (temperature). Nine species presented significant correlations between spatial synchrony and geographic distances (Astyanax sp. b, Astyanax sp. c, Pimelodus sp., Hoplias malabaricus, Crenicichla iguassuensis, Hypostomus derbyi, Hypostomus myersi, Rhamdia branneri, and R. voulezi). Considering the ecology of the species and the significant relationship between population and environmental synchronies, it seems that environmental stochasticity is the most plausible hypothesis in explaining the observed synchrony patterns.

Small mammal trapping in tropical montane forests of the upper Nilgiris, southern India: an evaluation of capture-recapture models in estimating abundance

Capture-mark-recapture was used to study small mammal populations in tropical montane forests in southern India. Eleven plots in six montane forest patches were sampled from February-October, 1994. Six species were captured, including four rodents and two shrews. PROGRAM CAPTURE was used to derive estimates of density of the most abundant species in the study area, Rattus rattus Linnaeus. The coefficient of variation of the density estimate was used as an index of precision. The coefficient of variation decreased exponentially with increasing capture probability and with an increase in trapping duration. The coefficient of variation and the capture probability were not correlated with estimates of density. The density estimate increased with trapping duration, as did trap mortality. The latter may have been due to the trend of increased mortality with recaptures of the same individual, which in turn may have been due to weight loss over consecutive captures. Estimates of density derived using four estimators were different for 2, 3, 4 and 5 days of trapping. The coefficient of variation was highest for the generalized removal estimate and lowest for Darroch's estimate. The models and estimators could not be applied to more than one species, and for this species, only in select habitats in a few seasons. Therefore, models of density estimation developed for temperate areas may not be suitable for tropical habitats due to low densities of small mammals in these habitats.