Ecological Indicators 24 (2013) 284–286 Contents lists available at SciVerse ScienceDirect Ecological Indicators journal homepage: www.elsevier.com/locate/ecolind Avian guano: A non-destructive biomonitoring tool for organic pollutants in environment M. Joshi a,∗ , P.P. Bakre b , P. Bhatnagar c a Environmental Biology Laboratory, Department of Zoology, University of Rajasthan, Jaipur 302015, India b Mahatma Gandhi Institute of Applied Sciences, Jaipur, India c International College for Girls, Autonomous, Jaipur, India article info Article history: Received 6 October 2011 Received in revised form 3 July 2012 Accepted 3 July 2012 Keywords: Guano Biomonitoring Organochlorine pesticides abstract Persistent organochlorine residues such as hexachlorohexane isomers (HCHs), chlorocyclodienes and DDT group (DDTs) were determined in fecal matter/guano of common wild pigeon (Columba livia) col- lected from rural, urban and suburban areas in Jaipur. Chlorinated contamination pattern varied largely among the three areas. Samples collected from rural areas of Jaipur contained greater concentrations of endosulfan (1.17 g/g dry wt) than those of urban and suburban areas. In contrast, fecal samples col- lected in suburban areas exhibited elevated levels of ∑ HCH (0.95 g/g dry wt) as compared with urban (0.46 g/g dry wt) and rural areas (0.82 g/g dry wt). Our study suggests that levels of organochlorine pesticide residues detected in avian guano are perhaps a reflection of the environmental status of the habitat. Thus avian guano may serve as a non-destructive biomonitoring tool for organic pollutants in environment. © 2012 Elsevier Ltd. All rights reserved. 1. Introduction The pesticide related issues have been increasingly and exten- sively highlighted in the media as well as research journals and have attracted sharp focus among policy makers in India and elsewhere too. Indiscriminate and excessive application of toxic synthetic pesticides damaged not only the environment and agriculture but also has entered into the food chain thereby affecting health and development. Organochlorine compounds such as PCBs, DDTs and cyclodiene groups are among the most widely known class of con- taminants because of their ubiquity, potential for magnification in the food chain, and harmful biological effects. Scientists have applied a variety of methods to monitor the pres- ence of these chemicals in the environment since not only the indication of presence of these chemicals in environment is of any consequence but also the response of biological system to it. Birds have extensively been used in the past as biomonitors of environmental contamination with persistent organic pol- lutants (Ramesh et al., 1992; Tanabe et al., 1998; Sethuraman and Subramanian, 2003). Certain species of birds, because of their worldwide distribution are considered good indicators of environmental pollution by pesticides (Moore, 1966). Many papers report data on predatory birds, which are considered particularly ∗ Corresponding author. E-mail address: meetjoshi23@yahoo.com (M. Joshi). useful for this purpose due to their trophic position in food chain (Law et al., 2003; Linderberg et al., 2004; Jaspers et al., 2006; Voorspoels et al., 2006). However, the natural scarcity of large predators restricts the availability of samples for analysis. Also, migratory birds might not be useful to determine the specific location in which pollutants are accumulated as they may have acquired contaminants from a wide range of geographical areas. Resident birds give the best reflection of the contamination in the local diet, as the movements of biomonitoring species must be limited if an accurate indication of site specific contamination level is to be obtained (Weseloh et al., 1994). In this sense, research was initiated to examine the potential value of a widespread bird, wild pigeon (Columba livia), as an indicator of contamination by organochlorine pesticides in Jaipur. The wild pigeon is common enough to permit the collection of large samples annually. It feeds mainly on grains and moreover, they are strict year-round resident birds. As a result, they may contain pollutants concentrations that may reflect significant differences between locations. Bird tissues are often used to assess the contamination of ecosys- tem by persistent pollutants. A colony of pigeon may contain life threatening levels of organochlorine pesticides, but sampling indi- vidual pigeon for chemical analysis is difficult for two reasons. First, the method of sacrificing or killing of animals is ethically unsound. Second, a sample of perhaps 10 pigeons would have to be analyzed to determine average contamination levels in an area. If these anal- yses were done individually, they would be costly but if a single analysis were done, it would be based on only 10 pigeons. Given 1470-160X/$ – see front matter © 2012 Elsevier Ltd. All rights reserved. http://dx.doi.org/10.1016/j.ecolind.2012.07.007