Faecal DNA typing to determine the abundance and spatial organisation of otters (Lutra lutra) along two stream systems in Kinmen

Abstract

In this study, non-invasive molecular methods were used to investigate the abundance and spatial organisation of otters (Lutra lutra) in Kinmen. DNA samples were extracted from fresh spraints collected seasonally along two streams from February to November 2001 and genotyped using a panel of 7 microsatellites and the SRY gene. Out of 343 spraints, 222 were successfully genotyped and 38 different genotypes (19 females and 19 males) were identified. Thirteen of these were residents that were identified in more than one season and 25 were floaters that were only identified in a single season. The average number of otters per km found along the two streams (1.5-1.8 for all otters, or 0.8-1.1 for residents only) was higher than that estimated in other studies. Female residents lived in exclusive group ranges and the ranges of male residents overlapped with no more than one group range of female residents. Otters appearing in the same range tended to be more closely related to each other. This study demonstrates that non-invasive molecular methods can be used to reveal a more comprehensive estimation of size and structure in an otter population.

Estima de la población de nutria en las Tablas de Daimiel mediante captura-recaptura espacial y muestreo de distancias

“…La medición de densidades por unidad de superficie en el agua es una tarea que por su dificultad raramente se ha acometido (Kruuk 1995, Sulkava 2007, RuizOlmo et al 2011. Recientemente se han utilizado técnicas genéticas (Hung et al 2004, Prigioni 2006, Prigioni & Remonti 2006, Arrendal et al 2007, Hájková et al 2008, Koelewijn & Pérez-Haro 2010, Lanszki et al 2010) y métodos de captura-recaptura basada en identificación de genotipos (Lampa et al 2013) pero también muestran ciertas limitaciones relacionadas con la técnica y el coste del análisis que limita el número de muestras y con ello la precisión. Asimismo se ha descrito la metodología del fototrampeo para la detección de la especie (Jones & Raphael 1993).…”

An evaluation of field and noninvasive genetic methods for estimating Eurasian otter population size

“…Reported success rates, though highly variable, are generally low, ranging from 14% to 73% (Jansman et al 2001;Dallas et al 2003;Hung et al 2004;Hájková et al 2005;Janssens et al 2008;Kalz et al 2006;Prigioni et al 2006a, b;Arrendal et al 2007;Ferrando et al 2008;Lanszki et al 2008). High levels of genotyping errors are typical for NGS, especially when polymerase chain reaction (PCR) success rates are not very high, a first indication of low quality and/or quantity of extracted DNA.…”

Research Activity and the Role of the Korean Otter Research Center

“…It was declared in August 2012 that the Japanese otter (Lutra lutra nippon) has already become extinct [4,8,5,9] in Japan. Furthermore, the number of Eurasian otters in China and Taiwan has recently been reported to be declining [2,[10][11][12].…”