Life sciences Leaflets 21:966 – 973, 2011. FREE DOWNLOAD ISSN 0976 - 1098

st Published on: 1 Nov 2011 POPULATION ESTIMATION OF IN GANDHINAGAR, GUJARAT S.N. DHANDHUKIA, K.B. PATEL AND P.K.PATEL* GUJARAT ARTS AND SCIENCE COLLEGE, AHMEDABAD-380006. *SPT ARTS AND SCIENCE COLLEGE, GODHRA. [email protected] ABSTRACT: Population study of three myna species (A. tristis), Bank Myna (A. ginginianus) and Brahminy Myna (S. pagodarum) was done in Gandhinagar, Gujarat during 2007 to 2009. Monthly populations of were a similar trend during the study peried. The Common Myna’s was the highest in the month of September, July and Octomber. Bank Myna numbers were highest in October. Brahminy Myna’s number was the highest in August, June and December at the feeding sites. Common Myna was dominant in number followed by Bank Myna and Brahminy Myna. Total population was Common Myna 1735, 2023 and 2139 (in 2007 to 2009), Bank Myna 1144, 1223 and 1361 (in 2007 to 2009) and Brahminy 148, 266 and 260 (in 2007 to 2009). Mynas are uniformly distributed in Gandhinagar. However, major resident population is near gardens and urban areas. KEY WORDS: Population estimation of Myna in Gandhinagar. INTRODUCTION: The myna belongs to the Domain (Carl woese 1990): Eukariota, Kingdom: Animalia, Phylum: Chordata, Class: Aves (), Order: Passeriformes and Family Sturnidae. The name of these attractive comes from the Hindi word maina, Mynas are classified in order Passeriformes and Family Sturnidae. Which is an emonstrative term usually applied to young girls. The genus literally means grasshopper-hunter, while the specific soubriquet, tristis, means sad, dreary or depressing. The rigin and distribution of myna is believed to be evolved from Asian Continent mainly from , Iran, Pakistan, Afghanistan and Kazakhstan. The Indian Subcontinent (Ali et al. 1983) is believed to be the origin. Mynas are one of the common birds through out India, observed in large populations in all climatic zones where it can survive (Ali et al. 1983).

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Life sciences Leaflets 21:966 – 973, 2011. FREE DOWNLOAD ISSN 0976 - 1098

Mynas are omnivores (Sengupta et al. 1976) and could potentially compete with a large range of indigenous species for food and also can cause severe damage to the agricultural crops (Narang et al. 1984) in the local community. In most parts of India, mynas are resident species. Mynas exhibit regional movement with seasonal changes in food availability that allows utilizing productive habitats available in other location / areas. However, it is difficult to understand seasonal pattern of habitat selection and its relation to food availability with short term of field observation. Common Myna often feeds on different food items depending on the time of year. This is due to the change in the availability of certain foods. Bank Myna visits its feeding grounds for the grains as well as insects. Brahminy Myna is habituated in feeding on both fruits and insects. Mynas extensively use cultivable fields particularly fields of cereal crops and fruit orchards. There are several methods to count the vertebrate populations (Davis 1982). However, census techniques show some methodological problems (Bull 1981, Dawson 1981) that many factors can influence the results and applicability of faunal census results. Wiens (1977) provides abundant illustrations of the extent to which methodology is critical to the valid interpretation of the results of bird counts. Appropriate methods for a particular study become more obvious if there is a clear purpose. A recurrent theme of good study design is that method must be tailored to aim. According to Pyke and Recher (1985), each census method has its advantages and disadvantages. It is important to employ a reliable census technique in which the user has confidence for the study of any avifaunal community. Besides the census method, which is being employed, for one species may not be applicable for another species. Therefore before employing any method for a particular species, it is important to assess the reliability of the method. Several expository papers deal generally with the census methods. Kendeigh (1944) reviewed estimates of bird population. Davis (1982) compiled and illustrated a number of census methods. Based on this information, in the present study on the general aspects of population census of three species, Common Myna (Acridotheres tristis), Bank Myna (Acridotheres ginginianus) and Brahminy Myna (Sturnus pagodarum) at Gandhinagar, Gujarat, India, are discussed. STUDY AREA: The study was confined to Gandhinagar city a District head-quarter and a picturesque town, which was the capital of the State of Junagadh. The Gandhinagar city is located between latitudes 23° 13' 0" N and 72° 41' 0" E. The weather is hot through the months of March to June when the maximum temperature stays in the range of 36 °C and 42 °C, and the minimum in the range of 19 °C and 27 °C. From November to February, the average maximum temperature is around 29 °C, http://lifesciencesleaflets.ning.com/ PEER-REVIEWED Page | 967

Life sciences Leaflets 21:966 – 973, 2011. FREE DOWNLOAD ISSN 0976 - 1098 the average minimum is 14 °C, and the climate is extremely dry. The southwest monsoon brings a humid climate from mid-June to mid-September. Gandhinagar, Gujarat's new capital city, rises on the west bank of the Sabarmati river, about 32 kms. north east of Ahmedabad, the commercial and cultural heart of Gujarat. Gandhinagar presents the spacious, well-organized look of an architecturally integrated city. MATERIALS & METHODS: For intensive study for population censes of mynas, four sites (Sector-19, Sector-25, Sector-28, and Sector-30) were selected in and around Gandhinagar city. Sites were selected on the bases of primary reconnaissance survey for the presence of the three myna species and their populations. All the sites were monitored in the first week each month for recording the number of birds. The foraging habitats of mynas were identified by following them in different directions during the early mornings, just after sunrise. The movement of birds was also observed by climbing up on high buildings located in different areas of the city to locate the foraging sites. The information was also gathered by interviewing the local people. Based on the pilot study of consecutive 10 days and the number of mynas at the feeding sites were recorded. It was assumed that the average number of the myna at the feeding sites remains constant for a period of at least a fortnight. Censuses were carried out in the first week of every month for 36 months at all the foraging sites in the study area. The observations were taken with the help of a pair of binoculars (8x 40) at a safe distance from the feeding flocks to avoid the disturbance to the birds. The numbers of myna at the foraging sites were counted either during mornings or during late evenings. The morning counts were started with the arrival of the first flock of mynas on the foraging ground. RESULTS: Monthly population of mynas at feeding sites during the three year revealed a similar trend. The Common Myna’s monthly population was found the highest in the month of September in 2007, July in 2008 and Octomber in 2009. Bank Myna numbers were found highest in October during the three years. Brahminy Myna’s number, during 2007 was the highest in August at the feeding sites. In 2008, maximum number of Brahminy Myna was observed in June followed by December in 2009 (Table 1, 2, 3). Common Myna was dominant in number followed by Bank Myna and Brahminy Myna during the study period at feeding sites (Figs. 1, 2, 3). Percentage distribution of Common Myna at feeding site was the highest at Sector-30 and few at Sector-28 and Sector-19. Its population at Gandhinagar Sector-19, Sector-25 and Sector-30 was http://lifesciencesleaflets.ning.com/ PEER-REVIEWED Page | 968

Life sciences Leaflets 21:966 – 973, 2011. FREE DOWNLOAD ISSN 0976 - 1098 more, but gradual increase was observed from Sector-25 to Sector-30 in 2007; 2008 and 2009. Whereas in 2007 maximum number was recorded from Sector-30 which gradually decreased in the order at Sector-25, Sector-19 and lowest number at Sector-28 (Fig. 4). In case of Bank Myna it was recorded feeding at all four sites i.e., Sector-19, Sector-25, Sector-28 and Sector-30. Its number was less in Sector-30 as compared to that at Sector-28 during both the years. Whereas maximum number was recorded in Sector-25 during the three year (Fig. 5). Brahminy Myna showed similar trend during the three years as it was found feeding at two sites only, their number gradually increased from Sector-19 to Sector-30 and achieved its maximum at Sector-30. In 2007 it was observed that the population was slightly higher than that in 2008 at Sector-30 but in 2009 slightly similar in Sector-19 and Sector-30. Whereas their number at Sector-30 was slightly low in 2008 than that in 2007 (Fig. 6). Table 1 Monthly population of mynas in 2007 at feeding sites. Month Common Myna Bank Myna Brahminy Myna January 115 95 5 February 136 94 11 March 115 69 14 April 80 56 20 May 88 51 4 June 141 40 8 July 178 69 22 August 195 95 24 September 206 145 10 Octomber 163 152 7 November 185 151 17 December 133 127 6 Table 2 Monthly populations of mynas in 2008 at feeding sites. Month Common Myna Bank Myna Brahminy Myna January 146 76 8 February 141 111 20 March 117 46 26 April 106 45 17 May 128 47 21 June 188 69 34 July 233 107 31 August 230 130 21 September 195 140 22 http://lifesciencesleaflets.ning.com/ PEER-REVIEWED Page | 969

Life sciences Leaflets 21:966 – 973, 2011. FREE DOWNLOAD ISSN 0976 - 1098

Octomber 181 180 25 November 192 165 21 December 166 107 20 Table 3 Monthly populations of mynas in 2009 at feeding sites. Month Common Myna Bank Myna Brahminy Myna January 153 67 7 February 222 91 16 March 114 43 10 April 88 67 14 May 112 60 8 June 138 80 26 July 228 118 26 August 219 160 34 September 194 171 23 Octomber 245 171 28 November 225 163 30 December 201 170 38 Fig. 1 Total population of mynas at feeding sites 2007.

Total population in 2007

148

1144 Common Myna Bank Myna

1735 Brahminy Myna

Fig. 2 Total population of mynas at feeding sites 2008

Total population in 2008

266

Common Myna Bank Myna 1223 2023 Brahminy Myna

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Life sciences Leaflets 21:966 – 973, 2011. FREE DOWNLOAD ISSN 0976 - 1098

Fig. 3 Total population of mynas at feeding sites 2009.

Total population in 2009

260

Common Myna Bank Myna 1361 2139 Brahminy Myna

40.00

35.00

30.00

25.00 2007 2008 20.00

Myna 2009 15.00

10.00

5.00 Percentage number of Common 0.00 ST-19 ST-25 ST-28 ST-30 Feeding site Fig. 4 Percentage number of Common Myna recorded in different feeding sites (Year – 2007 to 2009).

45.00 40.00 35.00 30.00 2007 25.00 2008 20.00 2009 15.00 10.00 5.00

Pecentage numberof Bank Myna 0.00 ST-19 ST-25 ST-28 ST-30 Feeding site Fig. 5 Percentage number of Bank Myna recorded in different feeding sites (Year – 2007 to 2009).

90.00 80.00 70.00 60.00 2007 50.00 2008 Myna 40.00 2009 30.00 20.00 10.00

Percentage number of Brahminy 0.00 ST-19 ST-25 ST-28 ST-30 Feeding site Fig. 6 Percentage number of Brahminy Myna recorded in different feeding sites (Year - 2007 to 2009). http://lifesciencesleaflets.ning.com/ PEER-REVIEWED Page | 971

Life sciences Leaflets 21:966 – 973, 2011. FREE DOWNLOAD ISSN 0976 - 1098

Abbreviations: ST = Sector DISCUSSIONS: Darwin (1859) pointed out the initial fact of population trend towards the stability over a time. It is understandable that a population of wild is subjected to continuous periodic fluctuations in a given time frame. Thus census techniques of any type like direct count, sampling or indices must not require excessive period of time to be completed successfully. In the present study, direct count method at the feeding sites seems to be quite reliable and accurate to estimate the population of the mynas at some selected feeding sites at Gandhinagar. It was also employed by Gadhvi (2001) for White Ibis and Dhandhukia (2010) for Myna. Usually the most common source of error encountered in the census is the difficulty to count accurately when the species in large flocks. However, during the study the arriving or departing flocks at the sites were small sized and easily countable accurately for most of the time. Mynas leave from the foraging site to the nearby tree branch shades during the hot hours of the day. Thus direct count method which seems most suitable and precise for the accurate estimation of the population. Population fluctuation due to dispersion and aggregation is a common feature among many wild animals. Seasonal movements are also known to occur in most of the mynas during the breeding season. Whole population of the three species of mynas in the study area was found to fluctuate seasonally and annually. The fluctuation in the population size was quite obvious, probably due to small census area with regular recording of data. It implies that the change in population size was the result primarily due to dispersion and aggregation of the mynas at the study area from the surrounding areas. The population in the study area reached to a peak usually at end of the breeding season (July- October depending on the species) when the juveniles leave the nesting and join the adults for foraging. The population of all the three mynas was found distributed throughout the study area. Local movement of population of mynas did occur. It was observed that all the mynas (especially banded chicks) that remained in the same territory which accounted for the variation in maximum number of mynas during peak in annual population fluctuation. Survey shows that the mynas are uniformly distributed. However, major resident population is found near gardens and urban areas. Aridity of land has restricted the growth of large trees and on the other hand, over-grazing of land, clearing pasture land for agriculture and domestic purpose

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Life sciences Leaflets 21:966 – 973, 2011. FREE DOWNLOAD ISSN 0976 - 1098 lead to the scarcity of large trees in Saurashtra. However, due to the religious feelings of people protect several trees like Peepal (Ficus religiosa) and Elephant fig (Ficus tsiela). REFERENCE: Ali, S., and Ripley, D. (1983). Handbook of the Birds of India and Pakistan. Oxford Univ. Press, Bombay.

Bull, E. L. (1981). Indirect estimate at abundance of birds, (Ralrh, C. J., and J. M. Scott, eds.). Estimating numbers of terrestrial birds. Studies in Avian Biology 6: 76-80.

Carl woese (1990). A new proposal: the three domains of life.

Darwin, C. (1859). The origin of species. London: Dent.

Davis, D. E. (1982). Hand book of census methods for terrestrial vertebrates. CRC Press,

Inc. Boca Raton, Florida, pp. 93-103.

Dawson, D. G. (1981). Counting birds for a relative measure (index) of density. In:

Estimating numbers of terrestrial birds (Ralph, C.J. and J.M. Scott eds.). Studies in avian biology 6: 12-16.

Dhandhukia, S.N. and Gadhvi, I.R. (2010). Population census of three myna species at feeding sites in Junagadh, Gujarat

Gadhvi, I. R. ( 2001). Ecological and behavioural studies on the White Ibis in Bhavnagar.

Ph. D. Thesis submitted to Saurashtra University, Rajkot

Kendeigh, S. C. (1944). Measurements of bird populations. Ecol. Monogr 14: 67-106.

Narang, M. L., Lamba, B. S. (1984). A contribution to the food habits of same Indian Mynas (Aves). Rec. Zool. Surv. India, Calcutta. Occasional paper 44:1-76.

Pyke, G. H., and Recher, H. F. (1985). Estimated forest bird densities by variable distance point counts. Aust. Wildl.Res 120: 307-319.

Sengupta, S. (1976). Food and feeding ecology of the Common Myna, Acridotheres tristis (L.). Proc. Indian Natn. Sci. Acad 42(6): 338-345.

Wiens. J. A. (1977). On competition and variable environment. Amer. J. Sci 65: 590-597.

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