Seasonal Occurrence, Distribution and Group Size of Irrawaddy Dolphins (Orcaella brevirostris) in the Bay of Brunei, Brunei Darussalam

The uniqueness of the Bay of Brunei makes it an ideal place to be inhabited by Irrawaddy dolphins. However, the increasing potential impacts of anthropogenic factors and environmental changes on the dolphins are alarming. The objectives of this study were to determine the seasonal occurrence and distribution, and to estimate the group size of Irrawaddy dolphins in the Bay of Brunei. Surveys were conducted between January 2016 and April 2018. The total distance surveyed was 2,439.2 km in 189.13 h (survey effort = 13,081.93 km.h). Forty-nine groups of Irrawaddy dolphins were recorded with a sighting rate of 0.37 per 100 km.h. Thirteen of the groups were observed with calves. Overall, the group size ranged between 1 and 15 individuals with a mean of 4.5 individuals (SD = 3.3). There was no statistical significance in the number of dolphin sightings between four different monsoon seasons (Northeast, Southwest, April Inter-monsoon, and October Inter-monsoon) (χ2 = 5.66, df = 3, p > 0.05). The number of sightings and number of individuals suggest that Irrawaddy dolphins are residents of the Bay of Brunei and are in need of a conservation management plan.

Optimizing the power of human performed audio surveys for monitoring the endangered Houston toad using automated recording devices

Knowledge regarding the locations of populations of endangered species is a critical part of recovery and facilitates land use planning that avoids unnecessary impacts. Regulatory agencies often support the development of survey guidelines designed to standardize the methods and maximize the probability of detection, thereby avoiding incorrectly concluding a species is absent from a site. Here, using simulations with data collected using automated recording devices (ARDs) we evaluated the efficacy of the existing U.S. Fish and Wildlife Service’s survey requirements for the endangered Houston Toad (Anaxyrus houstonensis). We explored the effect of (1) increasing survey duration, (2) increasing the number of surveys, and (3) combinations of environmental conditions (e.g., temperature, humidity, rainfall) on the detection probability and the number of surveys needed to be 95% confident of absence. We found that increases in both the duration of the survey and the number of surveys conducted decreased the likelihood of incorrectly concluding the species was absent from the site, and that the number of surveys required to be 95% confident greatly exceeded the existing survey requirements. Targeting specific environmental conditions was also an effective way to decrease the number of surveys required but the infrequency in which these conditions occurred might make application difficult in some years. Overall, we suggest that the survey effort necessary to achieve confidence in the absence of Houston Toads at a site is more practically achievable with the use of ARDs, but this may not be suitable in all monitoring scenarios.

A Survey on Currency Identification System for Blind and Visually Impaired

-At present the currency recognition for visually impaired and blind people has becomes a vital topic for the researchers in the different applications. The money exchange is an important part of our daily life activities. But it becomes very difficult for visually impaired and blind people to recognize the currency values in the financial exchanges and they easily betrayed by the other people. Accordingly, there seems an urgent requirement to scheme a framework that is useful in recognizing paper money notes accurately. There is a huge area for currency differential detection and it has evolved over many years. The paper explores currency identification and provides a comprehensive overview of the current literature on techniques for identifying currency notes, encouraging the survey effort to provide an effective system for blind and visually impaired people

A Survey on Currency Identification System for Blind and Visually Impaired

At present the currency recognition for visually impaired and blind people has become a vital topic for the researchers in the different applications. The money exchange is an important part of our daily life activities. But it becomes very difficult for visually impaired and blind people to recognize the currency values in the financial exchanges and they easily betrayed by the other people. Accordingly, there seems an urgent requirement to scheme a framework that is useful in recognizing paper money notes accurately. There is a huge area for currency differential detection and it has evolved over many years. The paper explores currency identification and provides a comprehensive overview of the current literature on techniques for identifying currency notes, encouraging the survey effort to provide an effective system for blind and visually impaired people

A new small-bodied, polymorphic Cnemaspis Strauch, 1887 (Squamata: Gekkonidae) allied to C. monticola Manamendra-Arachchi, Batuwita & Pethiyagoda, 2007 from the Central Western Ghats of Karnataka, India

We describe a new small-bodied, polymorphic Cnemaspis from near Hongadahalla village, Sakleshpur in the Central Western Ghats of Karnataka, India. Cnemaspis schalleri sp. nov. is allied to C. monticola and can be diagnosed from all other Indian Cnemaspis by its small body size; presence of spine-like tubercles on flank; heterogeneous dorsal pholidosis; presence of both precloacal and femoral pores in males; dorsal pholidosis of tail heterogeneous, composed of small, weakly keeled, flattened, sub-imbricate scales intermixed with enlarged, strongly keeled, distinctly pointed, conical tubercles forming whorls; slightly enlarged median row of sub-caudal scales, smooth at anterior half and strongly keeled posteriorly. The new species differs from C. monticola based on the number of dorsal tubercle rows at mid-body, the number of paravertebral tubercles, the number of precloacal pores and poreless scales between precloacal and femoral pores; besides 8.9–10.7 % uncorrected ND2 sequence divergence. We also provide the first description of topotypic males of C. monticola along with the first data on live colouration and natural history. Cnemaspis schalleri sp. nov. is the second new Cnemaspis described from around Sakleshpur within a span of less than a year with minimal field survey effort. It is almost certain than the dedicated systematic sampling across the Central Western Ghats will result in the discovery of many undescribed Cnemaspis lineages.

Survival Rates and Capture Heterogeneity of Bottlenose Dolphins (Tursiops truncatus) in the Shannon Estuary, Ireland

Adult survival is arguably the most important demographic parameter for long-lived species as it has a large impact on population growth, and it can be estimated for cetacean populations using natural markings and mark-recapture (MR) modelling. Here we describe a 26-year study of a genetically discrete, resident population of bottlenose dolphins in the Shannon Estuary, Ireland, conducted by an NGO using multiple platforms. We estimated survival rates (SRs) using Cormack-Jolly-Seber models and explored the effects of variable survey effort, multiple researchers, and changes in camera equipment as well as capture heterogeneity induced by changes in marks and site fidelity variation, all common issues affecting longitudinal dolphin studies. The mean adult SR was 0.94 (±0.001 SD) and thus comparable to the estimates reported for other bottlenose dolphin populations. Capture heterogeneity through variation in mark severity was confirmed, with higher capture probabilities for well-marked individuals than for poorly marked individuals and a “transience” effect being detected for less well-marked individuals with 43% only recorded once. Likewise, both SR and capture probabilities were comparatively low for individuals with low site fidelity to the Shannon Estuary, and SR of these individuals additionally decreased even further toward the end of the study, reflecting a terminal bias. This bias was attributed to non-random temporal migration, and, together with high encounter rates in Brandon Bay, supported the hypothesis of range expansion. Our results highlight the importance of consistent and geographically homogenous survey effort and support the differentiation of individuals according to their distinctiveness to avoid biased survival estimates.

Advanced survey effort required to obtain bat assemblage data in temperate woodlands (Chiroptera)

There is a lack of precise guidelines concerning the survey effort required for advanced bat surveys in temperate European woodlands, resulting in a lack of standardisation in survey methods. In this study we assess catch data from 56 bat trapping surveys at 11 UK woodland sites in order to provide recommendations for mist net survey effort required to gain meaningful bat assemblage data in temperate woodlands. Species accumulation curves were produced and were used to develop two novel values for survey effort: the minimum survey threshold (MST), whereby surveyors are more likely than not to encounter less dominant species; and the known species threshold (KST), the point where a given percentage (in our case, 75%) of the known species assemblage for a site is likely to be reached and beyond which there are diminishing returns for survey effort. For our data, the mean of MST was 17.4 net hours, and for KST, the mean was 29.8 net hours. The MST and KST values were reached during the second and third surveys, respectively. These proposed values are adaptable based on location and known species assemblage and may be used for planning advanced bat surveys in temperate woodlands not only to maximise survey efficacy and use of limited resources but to ensure ethical viability of undertaking advanced surveys in the first place.